阅读说明：本技术 使用磁感应的口腔内扫描系统 (Intraoral scanning system using magnetic induction ) 是由 M·V·福格德 C·瓦娜梅 M·佩德森 S·G·詹森 D·C·俄勒高奇 E·R·汉森 A 于 2020-02-27 设计创作，主要内容包括：公开了一种口腔内扫描系统,包括：-扫描设备,包括至少第一磁感应线圈；-可更换的扫描尖端,包括至少第二磁感应线圈；-扫描尖端可移除地连接到扫描设备；其中,至少第一磁感应线圈和第二磁感应线圈被配置为在扫描系统的操作期间在扫描设备和扫描尖端之间提供电力传输和/或通信信号。(An intraoral scanning system is disclosed, comprising: -a scanning device comprising at least a first magnetic induction coil; -a replaceable scanning tip comprising at least a second magnetic induction coil; -the scanning tip is removably connected to the scanning device; wherein at least the first and second magnetic induction coils are configured to provide power transfer and/or communication signals between the scanning device and the scanning tip during operation of the scanning system.)

1. An intraoral scanning system, comprising:

-a scanning device comprising at least a first magnetic induction coil;

-a replaceable scanning tip comprising at least a second magnetic induction coil;

-the scanning tip is removably connected to the scanning device;

wherein the at least first and second magnetic induction coils are configured to provide power transfer and/or communication signals between the scanning device and the scanning tip during operation of the scanning system.

2. A scanning system according to claim 1 wherein power transfer from the scanning device to the scanning tip comprises supplying an alternating voltage or current in the first magnetic induction coil, thereby inducing a current in the second magnetic induction coil.

3. A scanning system according to any preceding claim wherein providing a communication signal between the scanning device and the scanning tip comprises providing a frequency, phase or amplitude modulated alternating voltage or current to the first or second coil so as to induce a modulated signal in the other of the first or second coil, wherein the modulated signal comprises a communication transmission from the scanning device to the scanning tip or from the scanner tip to the scanning device.

4. Scanning system according to the preceding claim, wherein the scanning system is configured to demodulate the modulated signal.

5. A scanning system according to any preceding claim wherein the communication signal is placed in a different frequency band to the power transfer signal.

6. The scanning system of any one of the preceding claims, wherein:

-the scanning device further comprises a third magnetic induction coil;

-the scanning tip further comprises a fourth magnetic induction coil;

wherein the first and second magnetic induction coils are configured to provide power transmission and the third and fourth magnetic induction coils are configured to provide communications transmission.

7. Scanning system according to the previous claim, wherein the third and/or fourth communication transmission induction coil is twisted 180 degrees around a centre of symmetry, the third and fourth induction coil thus comprising two halves in a figure 8.

8. The scanning system of any one of the preceding claims wherein the scanning tip further comprises:

-an optical element at a distal end of the scanning tip having a reflective surface on an inner side of the scanning tip such that the scanning tip provides white light to the tooth when the optical element receives light from a white light source located in the scanning device, wherein the optical element is configured to receive white light reflected back from the tooth such that the scanning tip provides white light to a first image sensor in the scanning device when the optical element receives white light from the tooth; and

-an infrared light source configured to emit infrared light, the infrared light source residing in or on the replaceable scanning tip, whereby the scanning tip provides infrared light to the tooth.

9. An intraoral scanning system, comprising:

-a scanning device;

-a semi-replaceable scanning tip comprising at least a first magnetic induction coil;

-an infrared adapter configured to be replaceably attached to the scanning tip, the infrared adapter comprising at least a second magnetic induction coil and at least one infrared light source;

-a disposable or reusable sanitary sheath arranged between the scanning tip and the infrared adapter;

wherein the at least first and second magnetic induction coils are configured to provide power transfer and/or communication signals between the scanning device and the scanning tip during operation of the scanning system.

10. The intraoral scanning system according to the preceding claim, wherein the infrared adapter is configured to attach to the scanning tip by snapping and/or sliding onto the scanning tip.

11. A replaceable scanning tip for a scanning device, the scanning tip configured for intraoral scanning of a tooth, the scanning tip comprising:

-an optical element at a distal end of the scanning tip having a reflective surface on an inner side of the scanning tip such that the scanning tip provides white light to the tooth when the optical element receives light from a white light source located in the scanning device, wherein the optical element is configured to receive white light reflected back from the tooth such that the scanning tip provides white light to a first image sensor in the scanning device when the optical element receives white light from the tooth; and

-an infrared light source configured to emit infrared light, the infrared light source residing in or on the replaceable scanning tip, whereby the scanning tip provides infrared light to the tooth.

12. The replaceable scanning tip of claim 11 further comprising a replaceable infrared adapter comprising one or more light guides for directing infrared light from the scanning tip to teeth and/or gums.

13. The replaceable scanning tip of the preceding claim, wherein the light guide of the infrared adapter comprises a core and a cladding material, wherein the reflectivity of the core is higher than the reflectivity of the cladding such that the infrared light undergoes total internal reflection when passing through the one or more light guides.

14. The replaceable scanning tip of claim 12 wherein the light guide of the infrared adapter comprises one or more mirrors such that infrared light undergoes total internal reflection as it passes through the one or more light guides.

15. The replaceable scanning tip of any of claims 12-14, wherein the scanning tip and/or the infrared adapter further comprises one or more windows between the infrared light source and the one or more light guides.

16. A replaceable scanning tip according to the preceding claim, wherein the one or more windows are made of polymer and/or glass.

17. The replaceable scanning tip of any of claims 15-16, wherein the scanning tip comprises a first window placed beside the infrared light source and the infrared adapter comprises a second window, the first and second windows configured to couple infrared light from the infrared light source to the one or more light guides.

18. Replaceable scanning tip according to the previous claim, wherein the air gap between the infrared adapter and the first window is filled with a transparent cladding material.

19. The replaceable scanning tip of any of claims 11-18, wherein the infrared adapter is configured to attach to the scanning tip by snapping and/or sliding onto the scanning tip.

20. The replaceable scanning tip of any of claims 11-19, wherein the optical element is further configured to receive infrared light reflected back from the tooth such that when the optical element receives infrared light from the tooth, the scanning tip provides infrared light to the second image sensor.

21. The replaceable scanning tip of claim 20, wherein the second image sensor is the same as the first image sensor.

22. The replaceable scanning tip of claim 21, wherein the optical element is configured to reflect white light such that the white light passes to a first set of pixels on the first image sensor, and wherein the optical element is configured to reflect infrared light such that the infrared light passes to a second set of pixels on the first image sensor.

23. The replaceable scanning tip of any of claims 11-22, wherein the optical element is a mirror comprising a dielectric coating.

24. The replaceable scanning tip of any of claims 11-23, the tip further comprising one or more shutters at a distal end of the scanning tip, the shutters configured to block direct and/or indirect stray light.

25. The replaceable scanning tip of claim 24 wherein the infrared light source comprises a plurality of infrared light sources at the shutter.

26. The replaceable scanning tip of any of claims 24-25, wherein the shutter is formed as a protrusion integrated into one or more arms of the scanning device, the protrusion being placed over the infrared light source.

27. The replaceable scanning tip of any of claims 11-26, wherein the scanning tip further comprises an identification interface linked with an integrated memory located in the scanning tip, the identification interface configured to be read by an identification component located on the scanning device when the scanning tip is mounted on the scanning device.

28. The replaceable scanning tip of any of claims 11-27, wherein the scanning tip further comprises a printed circuit board integrated into the scanning tip, the printed circuit board configured to provide power from the scanning device to the infrared light source.

29. The replaceable scanning tip of any of claims 11-28, wherein the replaceable scanning tip comprises a tubular member comprising:

-a distal end comprising a first optical opening configured to transmit at least white light to a tooth, and

-a proximal end comprising a second optical opening configured to transmit at least white light from the scanning device to the first optical opening, and further comprising a mounting interface configured to mount the scanning tip to the scanning device.

30. The replaceable scanning tip of any of claims 11-29, wherein the replaceable scanning tip comprises a housing of at least two separate parts.

31. A scanning system, comprising:

-a replaceable scanning tip according to any of claims 11-30; and

-a scanner device configured to replaceably mount the replaceable scanning tip.

Technical Field

The present invention generally relates to a scanning system for intraoral scanning of teeth. More particularly, the present disclosure relates to the construction and function of a scanner tip of an intraoral scanner device using infrared transillumination and white light, and to a scanning system using magnetic induction for power transmission and/or communication.

Background

Scanner devices for intraoral scanning of teeth are well known in the scanning field.

In intraoral scanning of teeth and gums, data is typically acquired from within the oral cavity using a scanner device that provides white light or a combination of one or more different wavelengths of light to illuminate the oral cavity. Scanner devices typically have one or more image sensors for acquiring images or data from the scanning process.

WO2018/022940 describes an intra-oral scanner using infrared light in the range of 700 to 1090 nm. It describes how non-ionizing methods of imaging and/or detecting internal structures can be used, such as by illuminating structures within a tooth using one or more penetrating spectral ranges (wavelengths), acquiring images using penetrating wavelengths to view structures within a tooth, including using transmission-illumination (e.g., illuminating from one side and capturing light from the opposite side after passing through an object), and/or small angle penetration imaging (e.g., reflectance imaging, capturing light that has been reflected/scattered from internal structures while illuminating with penetrating wavelengths).

However, the design of scanner devices capable of capturing information about the scanned object using visible and infrared light wavelengths can be very complex.

Accordingly, there remains a desire in the intraoral scanning field to provide a scanner device having a simpler and less expensive design that is capable of utilizing light in both the visible and infrared wavelengths.

Disclosure of Invention

In one aspect, an intraoral scanning system is disclosed, comprising:

-a scanning device comprising at least a first magnetic induction coil;

-a replaceable scanning tip comprising at least a second magnetic induction coil;

-the scanning tip is removably connected to the scanning device;

wherein at least the first and second magnetic induction coils are configured to provide power transfer and/or communication signals between the scanning device and the scanning tip during operation of the scanning system.

By using magnetic induction coils for power transfer and/or communication between the scanner device and the scanning tip, no electrical contacts are required. This makes it possible to hermetically seal the scanner and scanning tip and to more easily clean surfaces that can now be leveled, reducing cleaning and sterilization challenges.

In some embodiments, the power transfer from the scanning device to the scanning tip comprises supplying an alternating voltage or current in the first magnetic induction coil, thereby inducing a current in the second magnetic induction coil.

In some embodiments, providing a communication signal between the scanning device and the scanning tip comprises providing a frequency, phase or amplitude modulated alternating voltage or current to the first or second coil to induce a modulated signal in the other of the first or second coil, wherein the modulated signal comprises a communication transmission from the scanning device to the scanning tip or from the scanner tip to the scanning device.

In this way, communications can be sent back and forth between the scanning device and the scanning tip.

In some embodiments, the scanning system is configured to demodulate the modulated signal.

In some embodiments, the communication signal is placed in a different frequency band than the power transfer signal.

This reduces possible interference between power transmission and communication signals.

In some embodiments, the scanning device further comprises a third magnetic induction coil; the scanning tip further comprises a fourth magnetic induction coil; and the first and second magnetic induction coils are configured to provide power transfer and the third and fourth magnetic induction coils are configured to provide communications transfer.

Thus, there will be a dedicated induction coil for power transfer and a dedicated induction coil for communication.

In some embodiments, the third and/or fourth communication transmission induction coil is twisted 180 degrees around the center of symmetry, such that the third and fourth induction coils comprise two halves of a figure-8.

This configuration of the coil has the following effects: placing the communication coil in a uniform alternating field, such as the power transfer field described above, causes the inductive input signals in the communication coil to cancel due to the opposite polarity of the induced current local to each twisted coil.

In some embodiments, the scanning tip further comprises:

an optical element located at a distal end of the scanning tip, having a reflective surface inside the scanning tip, such that the scanning tip provides white light to the tooth when the optical element receives light from a white light source located in the scanning device, wherein the optical element is configured to receive white light reflected back from the tooth, such that the scanning tip provides white light to a first image sensor in the scanning device when the optical element receives white light from the tooth; and

an infrared light source configured to emit infrared light, the infrared light source residing in or on the replaceable scanning tip, whereby the scanning tip provides infrared light to the tooth.

In this configuration, the same scanning device can be used for optical and infrared imaging.

In another aspect, disclosed herein is an intraoral scanning system comprising:

-a scanning device;

-a semi-replaceable scanning tip comprising at least a first magnetic induction coil;

-an infrared adapter configured to be replaceably attached to the scanning tip, the infrared adapter comprising at least a second magnetic induction coil and at least one infrared light source;

-a disposable or reusable sanitary sheath arranged between the scanning tip and the infrared adapter;

wherein at least the first and second magnetic induction coils are configured to provide power transfer and/or communication signals between the scanning device and the scanning tip during operation of the scanning system.

By using magnetic induction coils for power transfer and/or communication between the scanner device and the scanning tip, no electrical contacts are required. This makes it possible to hermetically seal the scanner and scanning tip and to more easily clean surfaces that can now be leveled, reducing cleaning and sterilization challenges. In addition, disposable or reusable sanitary sheaths may be replaced between each patient, thereby reducing the risk of infection between patients. The infrared adapter may also be disposable so that the portion that enters the patient's mouth may be discarded after use.

The infrared adapter may also be autoclavable so as to be reusable. Since the infrared adapter in this embodiment does not include any electronics, it can withstand more rigorous cleaning between uses.

In some embodiments, the infrared adapter is configured to attach to the scanning tip by snapping and/or sliding onto the scanning tip.

This allows easy attachment and removal of the infrared adapter before and after use.

In another aspect, a replaceable scanning tip for a scanning device is disclosed, the scanning tip configured for intraoral scanning of a tooth, the scanning tip comprising:

an optical element located at a distal end of the scanning tip, having a reflective surface inside the scanning tip, such that the scanning tip provides white light to the tooth when the optical element receives light from a white light source located in the scanning device, wherein the optical element is configured to receive white light reflected back from the tooth, such that the scanning tip provides white light to a first image sensor in the scanning device when the optical element receives white light from the tooth; and

an infrared light source configured to emit infrared light, the infrared light source residing in or on the replaceable scanning tip, whereby the scanning tip provides infrared light to the tooth.

Thus, since the scanner tip is replaceable, the design of the scanner device can be more flexible, have a simpler design and a cheaper manufacturing process.

In some embodiments, the replaceable scanning tip further comprises a replaceable infrared adapter comprising one or more light guides for directing infrared light from the scanning tip to the teeth and/or gums.

The infrared adapter in these embodiments can be made without any electronics and is therefore cheaper and easier to manufacture.

In some embodiments, the light guides of the infrared adapter include a core and a cladding material, wherein the reflectivity of the core is higher than the reflectivity of the cladding such that the infrared light undergoes total internal reflection when passing through the one or more light guides.

By having a core with a higher reflectivity than the cladding, the loss of infrared light is reduced.

In some embodiments, the light guide of the infrared adapter includes one or more mirrors such that infrared light undergoes total internal reflection when passing through the one or more light guides.

By having a mirror that reflects light, light losses due to bending in the light guide can be reduced.

In some embodiments, the scanning tip and/or the infrared adapter further comprise one or more windows between the infrared light source and the one or more light guides.

Having a window between the infrared light source and the light guide increases the coupling of light from the light source to the light guide.

In some embodiments, one or more windows are made of a polymer and/or glass.

In some embodiments, the scanning tip comprises a first window placed beside the infrared light source, and the infrared adapter comprises a second window, the first and second windows being configured to couple infrared light from the infrared light source to the one or more light guides.

This allows for partial separation between the infrared light source and the light guide.

In some embodiments, the air gap between the infrared adapter and the first window is filled with a transparent cladding material.

This allows reducing the effective refractive index difference between the infrared light source and the light guide.

In some embodiments, the infrared adapter is configured to attach to the scanning tip by snapping and/or sliding onto the scanning tip.

This allows easy attachment and removal of the infrared adapter before and after use.

In some embodiments, the optical element is further configured to receive infrared light reflected back from the tooth such that when the optical element receives infrared light from the tooth, the scanning tip provides infrared light to the second image sensor.

In these embodiments, the two image sensors of the optical system may be selected to have different sensitivities at different wavelengths of light. For example, the first sensor may be more sensitive to light having a wavelength in the visible spectrum, e.g., between 400 and 700nm, while the second sensor may be more sensitive to infrared light having a wavelength between 750nm and 1000 nm.

In some embodiments including two image sensors, the second image sensor is the same as the first image sensor. This allows for a simpler and cheaper scanning tip structure.

In some embodiments, the optical element is configured to reflect white light to pass to a first set of pixels on the first image sensor, and wherein the optical element is configured to reflect infrared light to pass to a second set of pixels on the first image sensor. In this way, a single sensor can be divided into pixel groups for detecting white light and infrared light, respectively.

In one embodiment, the optical element is a mirror.

In another embodiment, the optical element comprises a glass plate. In some embodiments, the optical element comprises an optical coating. An optical coating is one or more layers of material deposited on an optical element (e.g., a glass plate), for example to form a mirror. The optical coating changes the way in which the wavelength of light is reflected and/or transmitted on or in the optical element.

In a preferred embodiment, the optical coating is a dielectric coating. The dielectric coating comprises materials with different refractive indices made of multiple layers, wherein the thickness of the multiple layers may be selected according to the reflection and/or transmission of a specific wavelength. More specifically, by selecting the exact composition, thickness, and/or number of the plurality of layers, the reflectivity and/or transmittance of the coating can be adjusted to produce the desired characteristics. In one embodiment, the dielectric coatings are selected such that each layer is less than 300nm, such as less than 200nm, preferably about 100 nm.

An advantage of having the optical element comprise a dielectric coating, especially in case the optical element resides in the scanning tip, is that the desired characteristic (in an embodiment where the scanning tip is replaceable) can be replaced by another scanning tip having other desired characteristics. A dielectric coating placed on or incorporated in the optical element is an alternative solution to placing the dielectric coating on the optical element inside the scanning device, e.g. on the beam splitter or on top of the imaging sensor. This alternative solution therefore provides a more flexible scanning device, wherein the desired characteristics can be changed according to a specific scanning pattern. Another advantage of having the optical element comprise a dielectric coating is that scanning devices without a scanning tip (replaceable or non-replaceable) can be manufactured in an efficient manner without the need to apply a dielectric coating to surfaces inside the scanning device. This may therefore allow the scanning device to be produced in a more cost-effective manner.

In the most preferred embodiment, the dielectric coating is selected such that the refractive indices and thicknesses of the various layers provide a relative phase shift of about 0 degrees or 180 degrees between the S-polarized light and the P-polarized light. In some embodiments, the tolerance for the phase shift (about 0 or 180 degrees) may be less than plus or minus 15 degrees, such as plus or minus 10 degrees or such as plus or minus 5 degrees. In some embodiments, the phase shift is selected for light in the range between 400-600nm (e.g., between 500-575 nm). In some embodiments, the phase shift is selected for light in the range between 400-600nm (e.g., between 490-585 nm). For example, two different ranges may be selected for two different layers. An advantage of a polarization change of about 0 degrees between S-polarized light and P-polarized light is that the polarization does not change for the selected wavelength range. In this way, specular reflection from the tooth, for example, may be enhanced.

In another preferred embodiment, the dielectric coating is selected such that the refractive indices and thicknesses of the layers provide more than 90%, such as more than 95%, reflection for S-polarized light and P-polarized light. In a further preferred embodiment, the dielectric coating is selected such that the refractive indices and thicknesses of the layers provide a reflection of more than 80% for unpolarized light. In some embodiments, the reflection is selected for light having a wavelength in the visible domain, i.e., between 400-600nm, such as between 500-575nm, such as between 490-585 nm. For example, two different ranges may be selected for two different layers. In other and/or further embodiments, the reflection is selected for light in the infrared region, i.e. with a wavelength in the range between 700-1000nm, such as between 800-900nm, such as between 820-880 nm.

In the most preferred embodiment, the polarization and/or reflection is selected for an angle of incidence of between 30-60 degrees, such as between 40-50 degrees, such as about 45 degrees. This may enable light to be directed from the scanning device and into the oral cavity, e.g. without changing the polarization between S-polarized light and P-polarized light, and/or with high reflection (over 80%) for light in the visible and infrared domain, for example.

In some embodiments, the replaceable scanning tip includes one or more shutters at the distal end of the scanning tip that are configured to block direct and or indirect stray light. By minimizing the amount of stray light using shutters, excellent image quality can be ensured because stray light can generally reduce the available information in a captured image by blurring, overexposure, and/or causing glare in certain portions of the captured image.

In some embodiments, the replaceable scanning tip includes a plurality of infrared light sources located at or near the shutter. In a preferred embodiment, three IR LEDs are placed on each side of the scanning tip. The three IR LEDs may be electrically connected in series. In some cases, a dedicated connection from the scanning device provides power to all six IR LEDs. To distribute the current evenly between the two IR LED chains, a current mirror may be used. This helps to ensure uniform illumination of the infrared light. The scanning apparatus may also include circuitry that can measure the voltage and current supplied to the IR LEDs to determine and control the desired amount of infrared. As a safety measure, a temperature sensor may be placed near each infrared LED chain. If the temperature rises above the normal operating range, the temperature sensor will disconnect one or more, preferably all six, IR LEDs from the power supply by turning off the transistor connected in series with the IR LEDs. This may prevent the surface of the scanning tip from becoming too hot, which may cause discomfort or injury to the patient. It may also prevent excessive infrared light, since if too much power is supplied to the IR LEDs, they will become too hot, which is detrimental to the comfort and/or safety of the patient.

In some embodiments, the shutter comprises an integral shape on the inside of the distal end of the scanning tip, wherein the integral shape is configured to assist the user in correctly positioning the device relative to the teeth and gums. The shape of the integral portion may for example be in the form of a long protrusion located above the IR LED. This shape allows the user to position the device at will in any position with the teeth in range and/or with the tips properly positioned relative to the gums. The integral portion may alternatively be in the form of a pyramid, which allows the user to position the scanning tip in such a way that the pyramid-shaped protrusion is placed in the gap between the teeth. This ensures that the tip is properly positioned relative to the teeth and gums.

In one embodiment, the scanning tip further comprises an identification interface linked with an integrated memory located in the scanning tip, the identification interface configured to be read by an identification component located on the scanning device when the scanning tip is mounted on the scanning device.

In a second embodiment, the scanning tip comprises a plurality of connectors, e.g. pins (pins). For example, the identification interface may be part of a plurality of connectors. In one embodiment, the integrated memory may store the serial number and/or additional data. The integrated memory may be an EEPROM.

In some embodiments, the identification interface is at least in the form of an I2C interface. The I2C interface provides an SCL signal (I2C serial interface clock signal) and an SDA signal (I2C serial interface data signal). For example, two connectors may provide an I2C signal.

In another embodiment, the plurality of connectors is in the form of a first plurality of connectors and a second plurality of connectors, wherein the plurality of connectors are located at the proximal end of the scanning tip. The first plurality of connectors may be located at an upper position of the proximal end and the second plurality of connectors may be located at a lower position end of the proximal end. The first plurality of pins and the second plurality of pins may be identical. This may allow mounting the scanning tip to the scanning device in two positions.

In a preferred embodiment, the plurality of connectors form six pins. For example, in addition to two I2C connectors in the form of pins, there may be a common ground pin, and three voltage pins, such as a constant voltage pin, a first variable voltage supply, and a second variable voltage supply. The constant voltage pin may provide a voltage to digital logic circuitry in the scan tip. The first variable voltage pin may provide a voltage that heats an optical element in the scanning tip. The second variable voltage pin may provide a voltage to an infrared light source located on or in the scan tip.

In another preferred embodiment, the plurality of connectors form twelve pins. For example, six pins as described above may be located at an upper position of the proximal end, while six additional but identical pins may be located at a lower position of the proximal end.

In the most preferred embodiment, the plurality of connectors in the form of the first plurality of connectors and the second plurality of connectors are of the same type, but are positioned such that the first plurality of connectors are positioned along one arch and the second plurality of connectors are positioned along another arch. This may allow the scanning tip to be rotated from one position to another.

In another preferred embodiment, the plurality of connectors of the first plurality of connector forms and the second plurality of connector forms are of the same type, but are positioned such that the first plurality of connector forms is different from the second plurality of connector forms when the scanning tip is rotated from one position to another, e.g., 180 degrees. This may also allow the scanning tip to be rotated from one position to another, but may also allow the scanning device to identify differences, and thus whether the scanning tip is pointing up or down.

In some embodiments, the replaceable scanning tip includes a Printed Circuit Board (PCB) integrated in the scanning tip, the Printed Circuit Board (PCB) configured to provide power from the scanning device to the infrared light source. The PCB may comprise two L-shaped arms made of flexible PCB.

In some embodiments, white light is defined by light comprising one or more wavelengths in the range between 400nm and 700 nm. One advantage of using wavelengths in this range is that it allows capturing color information that actually corresponds to color information in real life.

In some embodiments, the replaceable scanning tip uses infrared light, which is defined by light comprising one or more wavelengths in the range between 750nm and 1000 nm. The use of infrared light in this wavelength range allows light to be transmitted through the gums and tooth material to illuminate the teeth from within.

In some embodiments, the replaceable scanning tip comprises a tubular member comprising-a distal end comprising a first optical opening configured to transmit at least white light to the tooth, and

a proximal end comprising a second optical opening configured to transmit at least white light from the scanning device to the first optical opening, and a mounting interface configured to mount the scanning tip to the scanning device.

In some embodiments, the replaceable scanning tip comprises a housing made of at least two different parts. The first portion may be referred to as a hard portion and is made of a plastic, such as polysulfone, PSU 1700, or similar plastics. The second portion, which may be referred to as a soft portion, is made of a biocompatible material, such as medical grade silicone rubber shore 60a or 70 a. Other similar materials may be used for the hard and soft portions of the scanning tip.

In some embodiments, the LEDs are placed in a retracted position in the soft portion. In these embodiments, the raised portion above the LED acts as an additional shutter. The remaining three sides around the LED may be tilted to allow maximum light output into the gums.

The front of the scanning tip serves both as a mechanical locking feature and as a bumper that minimizes the patient's perception in the event the device hits the back of the mouth and/or gums.

The long flat concave area extending below the tip can be used both as an area for applying glue and as a protective device to ensure that the device does not feel uncomfortable due to impact between the teeth and the aggregate. Furthermore, there may be several channels extending along the bottom section, which allows for easy alignment between the soft and hard parts when they are glued together during assembly.

The soft portion of the tip is made of a silicone material, which feels good and smooth, especially when it is wetted by saliva. This has the following effect: when the tip is manipulated into position, the user feels less friction of the material in the mouth, such as on the teeth, gums, tongue, or other soft tissue.

According to an aspect, a scanning system is disclosed, comprising:

-a replaceable scanning tip as described in any of the embodiments disclosed herein, and

a scanner device configured to replaceably mount a replaceable scanning tip.

By having a scanner device with an exchangeably mounted scanning tip, the scanner device will be more versatile. Other types of scanning tips may be used, and replaceable scanning tips may be replaced for each new patient, and/or may be autoclaved. This allows for a more hygienic scanning system.

Drawings

The above and/or further objects, features and advantages of the present invention will be further described by the following illustrative and non-limiting detailed description of embodiments of the present invention, with reference to the accompanying drawings, in which:

FIG. 1 shows a scanning system according to an embodiment of the present disclosure

FIG. 2 shows a side view of a scanning tip according to an embodiment of the present disclosure

FIG. 3 shows a side view of a first hard portion of a housing of a scanning tip in accordance with an embodiment of the present disclosure

FIG. 4 shows a view of a second soft portion of the housing of a scanning tip according to an embodiment of the present disclosure

FIG. 5 illustrates a side view of a scanning tip according to an embodiment of the present disclosure, showing first and second portions connected according to an embodiment of the present disclosure

FIG. 6A illustrates a frame for holding a mirror according to an embodiment of the present disclosure

FIG. 6B shows a PCB portion including a frame and a scanning tip of an arm for holding an infrared LED according to an embodiment of the present disclosure

FIG. 7A illustrates a first elastic mode of a scanning tip according to an embodiment of the present disclosure

FIG. 7B illustrates a second elastic mode of the scanning tip according to an embodiment of the present disclosure

FIGS. 8A-D illustrate a pyramidal shutter according to embodiments of the present disclosure

FIG. 9 illustrates an exemplary view of a scanning tip according to an embodiment of the present disclosure

FIG. 10 illustrates an assembly method according to an embodiment of the present disclosure

FIG. 11 shows a connector between a scanning tip and a scanner device according to an embodiment of the disclosure

FIG. 12A shows a scanning device and a replaceable scanning tip according to an embodiment of the present disclosure

FIG. 12B shows a configuration of a magnetic induction coil according to an embodiment of the present disclosure

13A-C illustrate various induction coil designs according to embodiments of the present disclosure

14A-B illustrate block diagrams of coil circuits according to embodiments of the disclosure

FIG. 15 shows a scanning system according to an embodiment of the present disclosure

16A-C illustrate light guide designs according to embodiments of the present disclosure

17A-D illustrate optical coupling designs according to embodiments of the present disclosure

FIG. 18A shows a scanning system in accordance with embodiments of the present disclosure

FIG. 18B shows details of an optical coupling design according to an embodiment of the present disclosure

FIG. 19 shows a scanning system according to an embodiment of the present disclosure

Detailed Description

In the following description, reference is made to the accompanying drawings that show, by way of illustration, how the invention may be practiced.

Fig. 1 illustrates a scanning system according to an embodiment of the present disclosure. In this example, the scanning system 1 is configured to perform an intra-oral scan of at least a portion of a tooth using at least infrared light.

Furthermore, in this example, the scanning system 1, more specifically the processor 7, is configured to operate in a second processing mode corresponding to intraoral scanning with at least infrared light using its scanning tip 5.

This second processing mode is initiated by having the intra-oral tip 5 distally mounted with a mirror that covers the entire optical field of view and directs the light from the scanner device 2 towards the object to be scanned. The intraoral tip 5 is shown installed. The tip is configured to be inserted into a mouth of a patient. Further, in one configuration of the scanning device 2, the light is selected to transilluminate the object to be scanned.

When the scanning tip 5 is mounted to the scanner device 2, the scanner device 2 reads identification data 17 in the form of an identification number 17 of the tip 5, which is stored on an internal memory of the scanning tip 5. The identification number is forwarded to the controller 8 located on an externally connected computer 11. Based on the scanner tip identification number 17, the controller 8 instructs the processor 7 on the scanner device 2 to process a continuous sequence of 2D images 15 recorded with infrared light illumination of the object. To this end, the scanner device 2 is configured to irradiate the subject with infrared light irradiated into the subject, for example, into teeth, and into the surrounding gums. The scanning tip 5 is configured such that red light is transmitted through the gum and tooth material to illuminate the tooth from inside. The infrared light irradiation is controlled by the controller 8 and is based on the scanner tip identification number 17. In other words, when the controller 8 receives the scanner tip identification number 17, the controller 8 additionally instructs the scanner device 2 to emit infrared light. Furthermore, the controller 8 additionally instructs the scanner device 2 to emit white light.

In this way, a regular sequence of images 15 is recorded with white light illumination. However, at a particular point in time, the white light recording is temporarily interrupted to record a single image 20 of infrared illumination. The interrupt is based on scan data feedback 21 between the controller 8 and the scanner device 2, the feedback 21 also being based on data 22 from the processor 7. The data 22 from the processor 7 may for example be a 2D image index number of the infrared image 19. The index number can be determined dynamically for each image in the sequence of images 15.

Further, when in the second processing mode, the processor 7 processes the white light image to derive data for 3D geometry and data for surface texture. Further, the processor 7 processes the single infrared light image to derive texture data of the internal structure of the object. Finally, the processor correlates texture data of the internal structure of the object with data of the 3D geometry.

In this example, the scanning application correlates the infrared image 15 with a corresponding location on the 3D model 13.

Fig. 2 shows a side view of a scanner tip 5 according to an embodiment of the present disclosure. The scanning tip 5 may be integrated in the scanning device or preferably be a replaceable scanning tip for a scanning device. The scanning tip 5 comprises a housing consisting of at least two different parts, hereinafter referred to as hard part 25 and soft part 26. The lower slope 27 of the soft portion 26 ensures that the aggregate does not collide with the front teeth when the aggregate is located over the largest tooth in range. The angling of this portion of the tip allows the tip to be moved into the mouth at an angle for optimal maneuverability and functionality. The shutter protrusions (not visible in this view) may also follow the same inclination.

The forward inclination 28 of the soft portion ensures that the device can be moved all the way into the mouth and the interproximal area between the two rear molars examined.

Fig. 3 shows a side view of a hard portion 25 of the housing of the scanning tip 5 according to an embodiment of the present disclosure.

Fig. 4 shows a view of a soft portion 26 of the housing of the scanning tip 5 according to an embodiment of the present disclosure. The soft portion of the housing includes a protrusion, here shown in the shape of the mushroom head 30, but other shapes may be equivalently used.

Fig. 5 shows a side view of the housing of scanning tip 5 after hard portion 25 and soft portion 26 have been attached together, according to an embodiment of the present disclosure. The interaction between the two parts comprises a number of features in order to lock them together mechanically, and have surfaces that allow sufficient adhesion to hold them together. The mechanical locking connection is the overlap of the front 51 of the soft part 26 and the hard part 25. The hard portion has a window opening 29 in which is provided a feature or protrusion to which the soft portion 26 mechanically snaps and secures in place. The tabs or features overlap the corners of the window opening to locate and mechanically hold the soft portion in place. The rear end of the soft portion 26 may include one or more features, shown here as mushroom heads 30 shaped to be placed on each side about a vertical central plane. Although shown here as symmetrically placed mushroom heads 30, other shapes and orientations may be equivalently used. The mushroom head 30 mechanically snaps into a complementary hole or window 29 included in the hard portion 25. All of the above features or protrusions also serve as surfaces for bonding the two parts together.

FIG. 6A shows a frame 33 for holding a mirror in a tip according to an embodiment of the present disclosure. The frame of the reflector may include a groove incorporated in the side wall to allow the PCB wings to extend from the PCB heater element portion and bend downward at the edge of the frame.

Fig. 6B shows a flexible Printed Circuit Board (PCB)34 of a scanning tip according to an embodiment of the present disclosure. The flexible PCB 34 includes two L-shaped arms 35 made of flexible PCB. Each of these arms is symmetrical and terminates in a rigid portion 36. Rigid portion 36 may be made of, for example, a glass reinforced epoxy laminate such as FR 4. Each arm of the PCB 34 includes one or more IR LEDs 37, here 3 LEDs 37 for example. The LEDs 37 are directed horizontally inward toward the central plane. In addition, the PCB 34 may have additional leads extending along the ridge connecting the LED37 to pin 6 in the baronet/pogo pin connection between the scanning tip and the scanner device.

Fig. 7A and 7B show how the soft segment 26 can be designed to take into account two different modes of elasticity. These two elastic modes are active simultaneously when the scanning tip is mounted on the scanner device.

The first spring pattern shown in fig. 7A rotates around the center portion of the respective wings descending on each side of the window opening. Essentially, the upper central part of the wings retains more material than the sides to allow this elastic mode to dominate, but also to allow the flexible PCB to be fixed and extend inside the silicone gel.

Having this elastic pattern can keep the center LED in place so it is most likely to be on the gums. When the center LED is optimally placed, the peripheral LEDs are unlikely to determine the location of the center LED, and therefore they will all be positioned in the most feasible manner.

The second mode of elasticity shown in fig. 7B is where the entire wing is bent from the soft portion end point at the edge of the window opening. It can be considered a cantilever where the entire arm bends when the shutter protrusion is positioned. The flexibility dominates over the shutter to allow the most feasible positioning of the LED on the gum within the tooth size of interest.

Fig. 7A and B further illustrate a shutter 31 according to an embodiment of the present disclosure. In this embodiment, there is one shutter 31 in the form of a long protrusion placed above the IR LEDs on each side of the scanning tip. This shape of the shutter allows the user to randomly position the device within the portion of the mouth of interest. To ensure that the device always rests on the bottom part of the tooth or the top of the gum, when the device is positioned, it is designed so that the distance between the two shutters on either side of the scanning tip is less than the narrowest tooth in the part of the mouth of interest. In addition to the shutter concept described above, the IR LED may also be retracted into the soft portion of the tip housing, as shown by the recess 32. The protrusion/overhang of the tip arm over the LED also serves an additional function to increase light blockage. The three remaining sides around the LED may be tilted to allow maximum light output into the gums.

Figures 8A-D illustrate another shape that may be used for the shutter. In this embodiment, the shutter is pyramidal in shape, which intuitively guides the user to position the device so that the interproximal areas between the teeth are located just below the center of the window opening. Various exact shapes of the pyramid structure can be envisaged, as shown in figures a-D. In addition to the shutter concept described above, the IR LED can also be retracted into the soft portion of the tip housing. The protrusion/overhang of the tip arm above the LED also serves to increase light blockage. The three remaining sides around the LED may be tilted to allow maximum light output into the gums.

Fig. 9 shows a view of the scanning tip 5 according to an embodiment of the present disclosure. The recessed IR LED37 and shutter protrusion 31 are shown. Also shown are the soft part 26 and the hard part 25 of the housing of the scanning tip.

Fig. 10 shows a stylized view of a method of assembly of a scanning tip in accordance with an embodiment of the present disclosure.

Fig. 11 illustrates a plurality of connectors, here shown as pins, between a scanning tip and a scanner device according to an embodiment of the present disclosure. A plurality of connectors are located at the proximal end of the scanning tip.

In another aspect shown in fig. 12A, an intraoral scanner system includes an intraoral scanner 2 and a replaceable scanning tip 5 adapted to fit over the distal end of the scanner and direct probe light from the scanner toward a subject to be scanned. The tip may be replaced for hygienic purposes, as it is common practice to remove the tip between treatments and clean and sterilize it before the next treatment. Scanner systems typically provide 2 or more tips to the end user so the user can use a clean tip on the patient while the other tips are being cleaned. This may enable uninterrupted workflow throughout a typical work day.

The scanning tip 5 may be designed as an active unit requiring power and data exchange. The physical contacts need to extend through the scanner body housing conductors to transmit power. The cavities introduced around the protrusions are susceptible to the ingress of biological matter and bacteria, which makes it challenging to ensure proper cleaning and disinfection of the cavities.

In these embodiments, the scanner system is designed such that it provides the possibility of exchanging electrical contacts with a magnetic induction interface 38, which magnetic induction interface 38 is capable of providing power and/or data exchange between the scanner and the active tip. It does so by magnetically coupling the coils in an arrangement that can reduce interference between data transmission and power transmission.

The scheme has at least the following three advantages;

1) no electrical contacts are required so that the scanner and tip can be hermetically sealed. This greatly reduces cleaning and sterilization challenges.

2) Improved reliability-eliminating the need for electrical contacts will reduce the risk of mechanical wear. The electrical contacts are the points in the product where failure is most likely to occur. The contact performance eventually degrades to the point where the product is unable to function properly due to mechanical wear. In prior art systems, careful mechanical design takes this into account by attempting to ensure that the failure of a function to operate in production is postponed to a point after the end of the product's useful life. Nevertheless, design tolerances and incorrect testing methods during development, coupled with unexpected user actions or unpredictable operating environment conditions, pose a risk of premature failure.

3) Complexity and size are reduced because the mechanical contacts require moving parts and require higher mechanical complexity. Reducing mechanical complexity allows for a more compact design.

The solution includes a power coupling mechanism and/or a communicative coupling mechanism.

This solution may be based on near-field magnetic induction and may be implemented in different ways.

The power transfer and communication may be performed simultaneously or separately during an exclusive period of time by one or the other mechanism.

Figure 12B shows a configuration showing the front part of the scanner system with the tip 5 mounted at the distal end of the scanner 2.

Power transfer is based on the physical characteristics of magnetic inductive coupling between adjacent conductor coils. The alternating current supplied in one coil (hereinafter referred to as TX coil 39) induces a current in the second coil (hereinafter referred to as RX coil 40) due to the magnetic coupling between the coils. The coupling k depends on the relative positioning of the coils and the geometry of the coils. A non-exhaustive list of various coil configurations is as follows:

a set of circular, elliptical or rounded-sided rectangular planar or non-planar coils, parallel to each other or placed at an angle with respect to each other, with their geometric centers aligned or close (as shown in fig. 12B).

A set of circular, elliptical or rounded-sided rectangular planar or non-planar coils, formed to conform to a circular shape, such as a tube, with its geometric center aligned or close.

A set of concentric spiral coils of different diameter, placed with their geometric centers aligned or close to each other.

All configurations may or may not have ferrite sheet backings for guiding magnetic fields.

The coil pairs are operated by applying an alternating voltage or current to the TX coil, generating an alternating magnetic field, which induces a current in the RX coil. The induced current can be further regulated in the accessory to provide a stable dc voltage supply.

System efficiency in terms of power transfer depends in part on the losses of the voltage regulation circuit in the accessory. The difference between the voltage level received by the accessory and the voltage output of the regulating circuit generates losses proportional to the load current of the electronic devices contained in the accessory. It is therefore feasible to be able to adjust the magnitude of the current induced in the RX coil to match the instantaneous load conditions. The accessory may be able to feed back information to the device regarding the instantaneous voltage amplitude, and the device may adjust the power accordingly by adjusting the amplitude or frequency of the AC signal applied to the TX coil.

The communication is additionally based on the physical characteristics of the magnetic inductive coupling between adjacent conductor coils. The alternating current supplied in one coil induces a current in the second coil due to the magnetic coupling between the coils.

The communication coil on the scanner device side will be referred to as MST coil 41, and the coil on the tip side will be referred to as SLV coil 42. The operating mode of the coil pair is to apply a frequency, phase or amplitude modulated alternating voltage or current to the MST coil 39 or to the SLV coil 40 by the tip through the device. The applied signal generates an alternating magnetic field that induces an electrical signal current in the receive coil, which may be a MST or SLV coil, depending on the direction of communication (scanning device to scanning tip or scanning tip to scanning device). The induced signal is demodulated according to the modulation scheme employed by the receiver.

The communication mechanism may be one of the above methods or a combination of both.

The inductive communication mechanism may be based on a dedicated communication coil or on the same coil set employed for the power transfer mechanism. Thus, the solution may comprise:

4 coils, with TX and RX for power, and MST and SLV for communication or

2 coils, where TX is the same as MST and RX is the same as SLV, or vice versa.

The 4 coil design is shown in fig. 13a for the scanner side interface. In this case, the magnetic fields from the TX and RX coils can cause significant noise signals on the MST and SLV coils. One way to eliminate interference from adjacent alternating magnetic transmission fields may be to use a special communication coil geometry, as shown in fig. 14b (only one side of the inductive interface is shown). This geometry causes the communication coils 41 and 42 (not shown) to twist 180 degrees around the center of symmetry, forming two halves, resulting in a shape of 8. In such a configuration, placing the communication coil 39 in a uniform alternating field, such as the power transmission field 41, causes the inductive signal in the communication coil to cancel due to the opposite polarity of the induced current local to each half of the two twisted coils.

By using the same twisted geometry on the MST and SLV coils, the applied communication signals do not cancel out due to the same local polarity of each half of the two coils. This communication arrangement is shown in fig. 13 c.

In the case of only 2 coils, the communication channel may be realized by frequency, phase or amplitude modulated signals, which are placed in another frequency band than the power transfer AC signal.

Communication may also be achieved by modulating the frequency of the supplied power transfer AC signal (by the device) and load modulation from the receiving side.

The coils may be placed at different locations of the scanning system. In the image of fig. 12B, a possible placement of a set of circular planar coils placed parallel to each other is shown. The illustration is based on a 4-coil solution.

Another embodiment includes a concentric helical coil, wherein the coil is two solenoids. One solenoid is part of the tip and the other solenoid extends inside the first solenoid and is part of the front tube assembly.

For any chosen solution, the power transmission coil may be connected to one or more capacitors in series or in parallel or in a combination thereof, constituting what will be referred to as a coil assembly hereinafter. The capacitance and the inductance of the coil determine the resonant frequency of the coil assembly.

The power transfer coil may be driven by a half-bridge or a full-bridge at a frequency above or below the resonant frequency of the coil assembly. As the frequency of the applied ac signal approaches the resonant frequency of the coil pair, the power transfer between the coil assemblies increases. Thus, the power transmission can be adjusted to match the requirements of the receiving device by modifying the operating frequency.

Another way to adjust the power transfer is by changing the amplitude of the AC signal supplied to the TX coil.

On the receive side of the power transfer, the induced current can be passively rectified by a diode bridge or actively rectified by a transistor full bridge. Voltage regulation may be accomplished by a switch mode power converter or LDO.

LDO solutions are preferred for their smaller solution size, and we will handle the ex I losses through power transfer management using a communication mechanism. To reduce the voltage overhead, the key difference between Qi and 3S differentiation (derivative) is therefore the addition of a dedicated communication physical layer for power arbitration. A block diagram of the transmitter coil excitation circuit is shown in fig. 14 a.

The communication may be based on UART. Standard UART implementations include dedicated RX and TX lines, but can be implemented in a loopback mode, requiring only a single shared physical medium. Restricting the protocol to loopback requires the transmitter to ignore the echo of the immediate loopback and the implementation will have a dedicated master to initiate all communications to avoid collisions.

The pulse duration (t _ os) is set to 1.25 times the carrier period, so the carrier will continuously re-trigger a single shot (oneshot) before its pulse duration expires. When triggered, the one-shot output indicates a logic 1. The one-shot output will settle to indicate a logic 0 only if the carrier does not re-trigger the one-shot within the pulse duration period. The logical output state may also be opposite to the presence of a carrier wave.

Fig. 14b shows an embodiment on the device side, where the processor on the scanner motherboard generates logical signaling. On the receive side, a separate u-controller provides this functionality. Otherwise, the solutions share the same features.

The communication may be based on an on-off keying carrier. Demodulation requires envelope tracking circuitry to decode the logic levels from the on-off keying carrier. For this purpose, a single shot retriggerable monostable multivibrator, for example, SN74LVC1G123, may be used. The pulse duration means a delay (t delay) from the disappearance of the carrier until the data line goes low. The worst case delay at the output of a single shot is 1.25 mus using a 1MHz carrier corresponding to a period of 1 mus. The UART accuracy requirement is 1.5%, imposing a minimum carrier burst length duration of 1,25e-6/0.015 ═ 83 μ s, corresponding to a baud rate of 12 kHz.

In this embodiment, the use of a u-controller on the receive side may be used.

Another option is to use an NFC tag (RFID) and reader solution to act as a transparent I2C bridge for communication between the scanner and the tip. In this case, the communication would be, for example, 13.56MHz amplitude shift keying, which is the standard for NFC. The device will host the reader and the accessory will host the tag. For this solution, the NXP NTAG5 series of labels is being considered. The area consumption of the additional side is not large, but is large on the equipment side. This would mean that the data transmission rate p is in the range of 10-100 kbit/s.

This option is based on the 1-wire protocol, where the device acts as a host and the MSP430 is placed on the receiving side. MSP430 can act as a book (TIDUAL 9A-2016 6-2016 7-2016 revise submission document for feedback copyright ownership2016, Texas instruments storage simulation use 1-Communication protocol) application description.The MSP430 will handle further communication with any other hardware in the tip through the downstream I2C slave device and also provide GPIOs for multiplexing potential LEDs, so a dedicated chip would not be needed for this purpose. This solution is somewhat laborious in the development process, but once implemented, is small. Alternatively, the receiving side may host a 1-Wire-to-I2C host bridge, such as Maxim DS28E 17. This solution is less adaptable on the accessory side and may have difficulty maintaining 1-Wire timing. DS2482X-100+ T is a substitute.

Alternatively, communication may also be achieved by modulating IR, UV or visible light from device to tip, tip to device, or both. The physical realization is by LEDs on the transmitting side and optical sensors on the receiving side. Depending on the communication mode implemented, the device and accessory may then include an LED, an optical sensor, or both for communication. A bluetooth system on chip, such as the DA14531 of Dialog semiconductors, may also be used. The antenna can then be implemented as shown in fig. 13 c. The advantage of this solution is high data rate, which would enable the use of external cameras and other high data rate features in the tip.

In another example shown in fig. 15, a scanning system 1 is shown having a scanning device 2, the scanning device 2 being configured with a manufacturer removable scanning tip 43, mounted to the scanner body in such a way that during normal operation of the scanner, the manufacturer removable scanning tip is actually stationary, located on a distal portion of the scanner, thus extending the scanner body into a front assembly containing the primary optical elements. The term manufacturer removable is used synonymously with the term semi-replaceable in this disclosure. This results in a semi-integrated scanning head that provides specific functionality to the scanning device. The scanning head can be detached from the body 2 by a technician and replaced with another according to a specific operating procedure. However, during routine operation, the scanner head 43 is considered to be permanently fixed and sealed during operation of the scanner. The scanning head is configured to couple with a sanitary sheath 44 that fits tightly around at least the scanning head to form a microbial barrier, such that only the sanitary sheath 44 needs to be sterilized or replaced between different patients. Such an arrangement allows the scan to require only moderate cleaning with a suitable wipe.

The reusable mechanical seal 45 between the scanner head and the scanner body 2 ensures that the microbial barrier can be successfully re-established after the scanner head is replaced by eliminating the need for any sterilization of the scanner front tube.

The tip interface of the scanning device is configured with a service connector interface 46 and a proximity sensor (e.g., hall sensor) 47 to enable detection of which sheath type is used on the scanner when the scanning tip is installed. The service connector interface is configured to couple with a connector on a Printed Circuit Board (PCB)48 located inside the scan head.

The scanning head includes an optical element 49 to direct the probe light from the scanner body toward the object to be scanned, and an optically transparent window 50 or prism element for sealing the interior of the scanning head from contact with the external environment while not affecting the probe light of the scanner. This can prevent any contamination of the interior of the scanner head and the front portion of the main scanner body.

In one arrangement shown in fig. 15, the scan head 43 is configured with a mirror 49; a transparent window (e.g., sapphire glass and quarter wave plate) 50 configured to transmit probe light from and to the scanner; and a flexible PCB 48 with dedicated heating elements for heating the window in the (ITO, resistive heater or induction heater) scanning head. In addition, the IR light source 37 may be attached to the PCB. The PCB may also contain multiplexers for individual IR led control. These IR LEDs 37 may be located in two arrays of 3 IR LEDs, one on each side of the scanning head 43.

The scanning head 43 is configured to couple with the multipurpose sanitary sheath 44 for standard scanning, however, upon identifying the additional IR adapter 51 (which is configured to fit outside the sanitary sheath on the scanning head), the scanner identifies the presence of the IR adapter and instructs the processor to enable the dedicated IR scanning mode. Such identification may be by identifying a portion of the IR adapter in the scanner FOW, instructing the processor to initiate a dedicated scanning mode.

In some embodiments, the IR adapter 51 shown in fig. 15 is configured to passively direct IR light from the scanning head 43 into the teeth and/or gums to provide IR transillumination of the patient's teeth. The IR adapter is configured to direct light from the LED through the structure. This means that there will be an optical coupling from the scanning head 43 to the passive IR adapter 51 part. This coupling may occur through the sanitary sheath 44. Some design considerations for such a solution include, but are not limited to:

the loss of light should be as small as possible, since the loss means that the LED has to emit more optical power and thus use more electrical power. In some embodiments, the scanning device may be wireless and therefore powered by one or more batteries. In this case, it is particularly important to conserve power usage before the battery must be recharged or replaced to extend the available scan time.

The total power available to the scanner is limited. The LED also dissipates heat and the outer surface of the tip should not reach temperatures above 41 c for safety regulations and patient comfort.

Light is emitted from the IR adapter device so as to well illuminate the entire field of view of the scanner. The IR adapter should be manufactured such that it can withstand frequent sterilization cycles, such as autoclaving or high level sterilization between uses.

The outer surface of the IR adapter is preferably smooth and free of cavities on the outside. The IR adapter should be made of a biocompatible material.

The housing of the IR adapter 51 may be comprised of one machined or molded part. Alternatively, the IR adapter may be assembled or manufactured from two or more injection molds or machined parts having different degrees of softness. The softer material used may have a durometer shore hardness value of a40-a 80. This makes the material smooth and comfortable for the patient when the IR adapter is placed in the patient's mouth during scanning. The IR adapter 51 may also include one or more additional rigid portions, such as a frame for stabilizing the structure, directing light, and configured to snap to the housing for attachment.

As for the selection of the LED37, the following criteria should be considered: the efficiency of the electrical to optical power conversion, the geometric emission distribution, and the extent, size, and thermal formation it allows coupling to the light guide.

The IR adapter 51 may include two flexible wings, allowing the device to fit various oral cavities and tooth sizes.

The portion of the housing where the IR adapter 51 is coupled to the scanhead may contain grooves and interacting surfaces on the sides of the housing to mechanically guide and ensure proper connection between the IR adapter 51 and the rest of the tip assembly (i.e., scanhead 43 and sanitary cover 44).

In some embodiments, the IR adapter 51 is made to direct light from the LED through the structure.

As shown in fig. 16a, in some embodiments, a light guide, or light pipe, or optical fiber, or waveguide 52 may be based on the principle of total internal reflection and have a core 53 and a cladding material 54, wherein the refractive index of the core is higher than the refractive index of the cladding. Both materials should be at least optically transparent to the respective wavelengths emitted by the LED37, typically IR light of 850nm, but wavelengths of 750nm to 950nm are also possible, and even longer wavelengths may be used if desired.

In other embodiments as shown in fig. 16b, the light guide may be based on a mirror 55 reflecting light from a reflective surface, such as a metal mirror (e.g. gold), a mirror based on total internal reflection or a dielectric mirror made of a thin layer of dielectric material. The main performance criterion in this respect is high reflection.

A solution with only one bend may be beneficial due to losses at the bend/mirror. For curved light guides, the light guide losses can be high, especially if the refractive index contrast between the cladding and the core is small and the bending radius is large. Thus, mirrors are instead often used to reflect light. Such mirrors may be based on the above principle, wherein mirrors based on total internal reflection are not very efficient if the angle is large and the refractive index contrast is low.

In the scanner configuration shown in fig. 15, light must be coupled from the LED to the light guide. If the flexible portion is not separated from the scanning tip, only one coupling is required. However, if the parts are separated, for example by a sanitary barrier, a second coupling is required. In this case, the portion between the LED and the light guide may be divided. In this case a window 56 may be introduced between the light guide and the LED, as shown in fig. 16 c. In this case, the coupling is generally more efficient if the distance and thickness are small, and if the refractive index difference is small, in order to minimize losses due to reflection from the window surface. The latter can be achieved by filling the air gap with a transparent material 57.

The window 56 may also be formed as a lens to make the coupling more efficient. Such a window/lens may be made of polymer or glass. The tip portion and the portion contacting the patient may also be separated such that light is coupled from the LED37 to the first light guide and then from the first light guide to the second light guide in the outer portion. In such a second coupling, the gap between the two conductors is critical: the smaller the gap, the higher the coupling efficiency. The alignment of the two light guides in the vertical direction is also critical for the coupling loss. Furthermore, the coupling efficiency may be improved by a second light guide having a different shape than the first light guide.

FIGS. 17A-D illustrate different improved optical coupling designs. If the second core is larger, better coupling efficiency can be obtained, fig. 17A. Furthermore, the shape of the second light guide may be tapered, as shown in fig. 17 b. This shape may be beneficial because the light will spread within the light guide to enable a larger volume of illumination in one direction (i.e. if multiple LEDs are used).

The coupling efficiency between the two light guides can be improved by introducing a focusing element, such as a lens. Such a lens may be formed separately beside the window, or as a window between two light guides, fig. 17c, or as an outline of a light guide, fig. 17 d. Coupling from the LED37 to the light guide 52 is generally more efficient the closer the LED is placed to the light guide. Lateral alignment is important and can be improved by a larger light guiding core compared to the size of the LED. In addition, tapered light guides can be used to improve coupling efficiency and to change the shape and size of the light guide.

The waveguides may be constructed as a single structure that projects light from a single LED, but they may also be constructed together, transmitting light from one or more LEDs carrying the light to a single exit point.

Another embodiment of a scanning system is shown in FIG. 18A, in which the scanning head 43 includes an IR light source 37 at the distal end and is connected to the scanner 2. The IR light source is protected by a window 56. The system is configured to couple with a multi-purpose sanitary barrier sheath 44. The sanitary sheath 44 additionally includes a coupling window area 56 that allows IR light to be transmitted through the sheath. Further, the IR adapter 51 is configured to be mounted on a sanitary cover when mounted on a scanner, so as to couple IR light from the scanning head into the light guide 52, transmitting illumination to the wing area of the IR light exit structure.

Details of possible coupling arrangements can be seen in fig. 18B.

A solution in which the light source is placed at the rear of the scanner head 43 may be beneficial because it allows keeping the mechanical dimensions of the distal end smaller, which is advantageous when scanning inside the oral cavity. Furthermore, the rear of the scanning head 43 may allow more space to be used for the light source and, for example, larger and/or higher power LEDs or lasers.

Light from the light source may be coupled into the tapered light guide. In these embodiments, sheath window 57 is placed as part of sanitary barrier sheath 44 or as a separate unit, then allowing a disposable transparent sheath to be placed on top. The light guide 52 is curved to direct light down to the bottom end of the tip where it exits the tip. The losses at the window can be high due to coupling losses and reflections. Coupling losses can be minimized by precisely controlling the position of the two light guides relative to each other. The window may be formed as a lens and the end of the light guide may be formed as a lens. It may be beneficial to have two lens elements: one for collimating light and the other for focusing light.

In another configuration shown in fig. 19, the scanning head 43 is provided with a mirror 49; a transparent window (sapphire glass and quarter wave plate) 50 configured to transmit probe light from and to the scanner; and a flexible PCB 48 with dedicated heating elements for heating the window in the (ITO, resistive heater or induction heater) scanning head. In addition, the inductive interface 38 is placed behind the optical element 49 on the scan head and also inside the IR adapter 51. The IR adapter 51 may contain one or more infrared light sources, such as two arrays of three IR LEDs 37 on each side. The scan head 43 may also include a multiplexer for individual IR LED control. These IR LEDs 37 may be located in two arrays of three IR LEDs 37 in each wing. The inductive interface 38 is configured to transmit power for powering the IR LED37 and data transmission for controlling lighting. The IR adapter 51 is configured to fit over the distal end of the scanhead when the sanitary sheath 44 is placed. In fig. 19, the sanitary sheath is shown as a single use sheath, but a multiple use sheath or sleeve may be used.

The manufacturer removable scan head 43 may provide several advantages over the easy instant removable scan tip 5. It is designed for simple hygienic barrier sheaths. This reduces the complexity of the part of the scanner (i.e. the barrier sheath) that needs to be sterilized between patients. All optical elements as well as the PCB heating elements and electrical connectors are integrated behind the microbial barrier, which ensures that they do not have to be designed for manual cleaning/high-grade disinfection solutions or for disinfection in an autoclave.

The fact that the optical elements for directing the probe light towards the object are protected inside the scanning head 43 results in a longer lifetime and less attenuation of the optical elements, so that frequent recalibration adjustments need not be performed when relying on operation of the mirrors attached in the tip 5 or color correction. A scanning system suitable for use with a scanner head 43 solution system can be easily upgraded to accommodate new functions and requirements by simply replacing the scanner head. In the event that the scanner accidentally falls during operation, the front portion of the scanner is often susceptible to damage, resulting in the scanner device not working properly. This type of damage usually requires extensive repair at specialized technical facilities. The disclosed scan head solution provides a way to absorb this impact energy and then easily replace it. This makes the maintenance of the scanner faster and less inconvenient for the user, as it can be performed by a technician at the user's location.

Since the optical elements for directing the probe light towards the object to be scanned are confined in the scanning head 43 instead of in the tip sheath 5, no frequent color calibration is required compared to an open tip containing optical elements.

In the device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims or described in different embodiments does not indicate that a combination of these measures cannot be used to advantage.

Although some embodiments have been described and shown in detail, the invention is not limited to them, but may also be implemented in other ways within the scope of the subject-matter defined in the following claims. In particular, it is to be understood that other embodiments may be utilized and structural and functional modifications may be made without departing from the scope of the present invention.

The claims may refer to any of the preceding claims and "any" is understood to mean "any one or more of the preceding claims.

The term "obtaining" as used in this specification may refer to physically acquiring, for example, a medical image using a medical imaging device, but it may also refer to, for example, loading a previously acquired image or digital representation into a computer.

It should be emphasized that the term "comprises/comprising" when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

The features of the methods described above and below may be implemented in software and executed on a data processing system or other processing device resulting from the execution of computer-executable instructions. The instructions may be program code means loaded in a memory, such as a RAM, from a storage medium or from another computer via a computer network. Alternatively, the described features may be implemented by hardwired circuitry instead of software or in combination with software.