阅读说明：本技术 一种中波双色切换的红外热成像系统 (Infrared thermal imaging system with medium-wave double-color switching ) 是由 李玉萍 苏盈 乔磊 于 2020-10-16 设计创作，主要内容包括：一种中波双色切换的红外热成像系统,包括：步进电机、转盘、滤光片、光电开关、探测器；本发明公开的一种中波双色切换的红外热成像系统,通过第一滤光片和第二滤光片将传统的中波段3.7～4.8μm的单色波段先后分成3.7～4.1μm和4.2～4.8μm的窄双色波段,在时域上依次得到两个窄波段的辐射能量,再对两个波段的图像信息进行融合,实现了窄双色波段的图像采集,抗干扰能力强,提高图像识别能力。本发明仅使用步进电机和光电开关进行运动控制,成本比较低。本发明不仅可以用于双色切换,还可以用于快门补偿以及快速定位,功能更加齐全。(A medium wave dual color switched infrared thermal imaging system comprising: a stepping motor, a turntable, an optical filter, a photoelectric switch and a detector; according to the infrared thermal imaging system with medium-wave two-color switching, the single-color waveband of 3.7-4.8 mu m of the traditional medium-wave band is divided into the narrow two-color waveband of 3.7-4.1 mu m and 4.2-4.8 mu m by the first optical filter and the second optical filter, the radiation energy of the two narrow wavebands is obtained in sequence in the time domain, and then the image information of the two wavebands is fused, so that the image acquisition of the narrow two-color waveband is realized, the anti-interference capability is high, and the image identification capability is improved. The invention only uses the stepping motor and the photoelectric switch to control the movement, and has lower cost. The invention can be used for double-color switching, shutter compensation and quick positioning, and has more complete functions.)

1. An infrared thermal imaging system with medium wave dual color switching, comprising: a stepping motor, a turntable, an optical filter, a photoelectric switch and a detector; wherein:

the stepping motor is connected with the turntable, works at a preset rotating speed, is used for driving the turntable to rotate at the preset speed, and is also used for receiving a turntable periodic signal sent by the photoelectric switch and counting the rotating steps of the stepping motor;

the turntable is preset with a first optical filter and a second optical filter and is used for driving the optical filters to rotate at a preset speed; an infrared light acquisition area is also preset and is used for acquiring image information of the two-color wave band of the first filter and the second filter;

the optical filter is divided into a first optical filter and a second optical filter and is arranged on the rotary table according to a preset position, wherein the first optical filter and the second optical filter divide a middle-band monochromatic band into a middle-band narrow dual-color band, and when the first optical filter and the second optical filter pass through the rotary table acquisition region, the infrared light information of the dual-color band of the first optical filter and the infrared light information of the dual-color band of the second optical filter are acquired respectively;

the photoelectric switch is arranged outside the turntable, and when the turntable rotates for a period, the period information of the turntable is obtained and sent to the stepping motor, and the stepping motor is controlled to count the rotating steps;

and the detector is used for receiving the double-color waveband infrared light information of the filter plate and converting the double-color waveband infrared light information into infrared image information.

2. The medium wave dual color switched infrared thermal imaging system of claim 1, wherein the turntable is further pre-configured with a shutter compensation zone for shutter compensation of the infrared thermal imaging system.

3. The infrared thermal imaging system of claim 1, wherein the first filter is a 3.7-4.1 μm filter, and the second filter is a 4.2-4.8 μm filter.

4. The medium-wave dual-color switched infrared thermal imaging system of claim 1, wherein the first optical filter and the second optical filter are mounted on the turntable in a manner that: the first filter and the second filter respectively occupy a quarter circle of the turntable, and the first filter and the second filter are symmetrical with respect to the center of the turntable.

5. A medium wave dual color switched infrared thermography system as in claim 1, in which the stepper motor speed is 1500r/min, the pulse frequency is 5000Hz, and each step of the stepper motor is 1.8 °.

6. A medium wave dual color switched infrared thermography system as claimed in claim 5, which, when the infrared thermography system is in the dual color switched mode, operates by: when the infrared light acquisition area is in the first optical filter or the second optical filter, and the stepping motor receives a photoelectric switch signal, counting the number of steps of the motor by N clear 0, adding 1 to N when the stepping motor moves by one step, if N is not less than 5 and not more than 15, not changing the stepping frequency, maintaining the stepping frequency, if N is more than 15, reducing the stepping frequency of the motor, and if N is less than 5, increasing the stepping frequency of the motor.

7. A medium wave dual color switched infrared thermal imaging system according to claim 1, characterized in that when the infrared thermal imaging system is in shutter compensation mode, the method of operation is: and the step motor enters a preset position of the shutter compensation area, and the step number of the step motor is determined according to the horizontal angle of the step motor and the rotating angle of each step number of the step motor.

8. A medium wave dual color switched infrared thermal imaging system as set forth in claim 1 wherein the stepper motor is centered in the shutter compensation zone and the number of steps of the stepper motor is 75.

9. A medium wave dual color switched infrared thermography system as claimed in claim 5, which, when the infrared thermography system is in locate mode, operates by: and acquiring an angle theta from a position to be positioned to the photoelectric switch, clockwise rotating until the photoelectric switch is met, clearing the pedometer N of the step switch at the moment, and determining the step count of the step switch to be theta/1.8 degrees according to the angle theta and each step degree of the step switch.

Technical Field

The invention relates to the technical field of infrared thermal imaging, in particular to an infrared thermal imaging system with medium-wave two-color switching.

Background

Infrared thermal imaging uses a photoelectric technology to detect infrared specific waveband signals of object thermal radiation, converts the signals into images and graphs which can be distinguished by human vision, and can further calculate temperature values. The part with the wavelength of 0.78-2.0 microns is called near infrared, and the part with the wavelength of 2.0-1000 microns is called thermal infrared. When the infrared is transmitted on the ground surface, the infrared is absorbed by the substances forming the atmosphere, the intensity is obviously reduced, the infrared thermal imager has better penetration rate only in two wave bands of 3-5 μm of medium wave and 8-12 μm of long wave, most of the infrared thermal imagers detect the two wave bands,

in the prior art, the mid-band infrared thermal imaging technology is developed rapidly, the application scene exceeds the long-band infrared thermal imaging technology with the same specification, however, for the mid-band infrared thermal imaging technology, the mid-band monochromatic band infrared thermal imaging system is mainly used at present. The target identification accuracy is high for objects with the same temperature and material, however, for objects with different temperatures and materials, the infrared radiation characteristics in different wave bands are different, and if the background is complex, the target identification is likely to be inaccurate.

Disclosure of Invention

In view of the above, the present invention has been developed to provide a medium-wave two-color switched infrared thermal imaging system that overcomes or at least partially solves the above-mentioned problems.

In order to solve the technical problem, the embodiment of the application discloses the following technical scheme:

an infrared thermal imaging system with medium wave dual color switching, comprising: a stepping motor, a turntable, an optical filter, a photoelectric switch and a detector; wherein:

the stepping motor is connected with the turntable, works at a preset rotating speed, is used for driving the turntable to rotate at the preset speed, and is also used for receiving a turntable periodic signal sent by the photoelectric switch and counting the rotating steps of the stepping motor;

the turntable is preset with a first optical filter and a second optical filter and is used for driving the optical filters to rotate at a preset speed; an infrared light acquisition area is also preset and is used for acquiring image information of the two-color wave band of the first filter and the second filter;

the optical filter is divided into a first optical filter and a second optical filter and is arranged on the rotary table according to a preset position, wherein the first optical filter and the second optical filter divide a middle-band monochromatic band into a middle-band narrow dual-color band, and when the first optical filter and the second optical filter pass through the rotary table acquisition region, the infrared light information of the dual-color band of the first optical filter and the infrared light information of the dual-color band of the second optical filter are acquired respectively;

the photoelectric switch is arranged outside the turntable, and when the turntable rotates for a period, the period information of the turntable is obtained and sent to the stepping motor, and the stepping motor is controlled to count the rotating steps;

and the detector is used for receiving the double-color waveband infrared light information of the filter plate and converting the double-color waveband infrared light information into infrared image information.

Furthermore, a shutter compensation area is also preset in the turntable and used for carrying out shutter compensation on the infrared thermal imaging system.

Furthermore, the first filter is a filter with a diameter of 3.7-4.1 μm, and the second filter is a filter with a diameter of 4.2-4.8 μm.

Further, the specific manner of mounting the first optical filter and the second optical filter on the turntable is as follows: the first filter and the second filter respectively occupy a quarter circle of the turntable, and the first filter and the second filter are symmetrical with respect to the center of the turntable.

Further, the rotating speed of the stepping motor is 1500r/min, the pulse frequency is 5000Hz, and each step of the stepping motor is 1.8 degrees.

Further, when the infrared thermal imaging system is in a two-color switching mode, the working method comprises the following steps: when the infrared light acquisition area is in the first optical filter or the second optical filter, and the stepping motor receives a photoelectric switch signal, counting the number of steps of the motor by N clear 0, adding 1 to N when the stepping motor moves by one step, if N is not less than 5 and not more than 15, not changing the stepping frequency, maintaining the stepping frequency, if N is more than 15, reducing the stepping frequency of the motor, and if N is less than 5, increasing the stepping frequency of the motor.

Further, when the infrared thermal imaging system is in the shutter compensation mode, the working method comprises the following steps: and the step motor enters a preset position of the shutter compensation area, and the step number of the step motor is determined according to the horizontal angle of the step motor and the rotating angle of each step number of the step motor.

Further, the stepping motor enters the center position of the shutter compensation area, and the number of steps of the stepping motor is 75.

Further, when the infrared thermal imaging system is in the positioning mode, the working method comprises the following steps: and acquiring an angle theta from a position to be positioned to the photoelectric switch, clockwise rotating until the photoelectric switch is met, clearing the pedometer N of the step switch at the moment, and determining the step count of the step switch to be theta/1.8 degrees according to the angle theta and each step degree of the step switch.

The technical scheme provided by the embodiment of the invention has the beneficial effects that at least:

according to the infrared thermal imaging system with medium-wave two-color switching, the single-color waveband of 3.7-4.8 mu m of the traditional medium-wave band is divided into the narrow two-color waveband of 3.7-4.1 mu m and 4.2-4.8 mu m by the first optical filter and the second optical filter, the radiation energy of the two narrow wavebands is obtained in sequence in the time domain, and then the image information of the two wavebands is fused, so that the image acquisition of the narrow two-color waveband is realized, the anti-interference capability is high, and the image identification capability is improved. The invention only uses the stepping motor and the photoelectric switch to control the movement, and has lower cost. The invention can be used for double-color switching, shutter compensation and quick positioning, and has more complete functions.

The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic view of an infrared thermal imaging system with medium-wave two-color switching according to embodiment 1 of the present invention;

fig. 2 is a flowchart of an infrared thermal imaging system with medium-wave two-color switching in a two-color switching mode according to embodiment 1 of the present invention;

fig. 3 is a schematic diagram of a shutter compensation mode of an infrared thermal imaging system with medium-wave two-color switching according to embodiment 2 of the present invention;

fig. 4 is a schematic view of an infrared thermal imaging system with medium-wave two-color switching as a positioning mode in embodiment 2 of the present invention.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

In order to solve the problems that the background of an infrared thermal imaging system of a medium-wave monochromatic waveband is complex and target identification is inaccurate in the prior art, the embodiment of the invention provides an infrared thermal imaging system for medium-wave bicolor switching.

Example 1

Referring to fig. 1, a medium-wave two-color switched infrared thermal imaging system includes: a stepping motor, a turntable, an optical filter, a photoelectric switch and a detector; wherein:

the stepping motor is connected with the rotary disc and works at a preset rotating speed, is used for driving the rotary disc to rotate at a preset speed and is also used for receiving a rotary disc periodic signal sent by the photoelectric switch and counting the rotating steps of the stepping motor.

Specifically, in some preferred embodiments, after the servo board is powered on, the stepping motor is started to rotate at a uniform speed of 1500r/min, and assuming that each step of the stepping motor is 1.8 °, one turn corresponds to 200 pulse signals, and the calculation formula of the rotation speed v (rpm) is as follows:

speed of rotation V (rpm) ═ pulse frequency (f) × 60/number of steps per revolution (n)

F is calculated to be 5000Hz by a formula. Because the angles of the motors in each step are not completely equal, a lot of errors always exist, and the frequency needs to be adjusted according to actual conditions.

The turntable is preset with a first optical filter and a second optical filter and is used for driving the optical filters to rotate at a preset speed; an infrared light acquisition area is also preset and used for acquiring the image information of the two-color wave band of the first filter and the second filter. In some preferred embodiments, the turntable is also preset with a shutter compensation area for performing shutter compensation on the infrared thermal imaging system.

The optical filter is divided into a first optical filter and a second optical filter and is arranged on the rotary table according to a preset position, wherein the first optical filter and the second optical filter divide the middle-band monochromatic band into middle-band narrow dual-color bands, and when the first optical filter and the second optical filter pass through the rotary table collecting area, the infrared light information of the dual-color bands of the first optical filter and the second optical filter are collected respectively.

In this embodiment, the first filter is a 3.7-4.1 μm filter, and the second filter is a 4.2-4.8 μm filter. The monochromatic bands of 3.7-4.8 mu m are divided into narrow bicolor bands of 3.7-4.1 mu m and 4.2-4.8 mu m by the filter plate, and then the image information of the two bands is fused to obtain more real target information.

In this embodiment, the specific manner in which the first optical filter and the second optical filter are mounted on the turntable is as follows: the first filter and the second filter respectively occupy a quarter circle of the turntable, and the first filter and the second filter are symmetrical with respect to the center of the turntable.

Specifically, as shown in fig. 1, since the frequency of the detector is 50Hz, that is, each frame of image is 20ms, the system needs to rotate the filter disc to output 2 frames of images each time the system rotates one cycle, the detector adopts an integration while integration read (IWR) integration mode, and experiments show that the integration time required for storing charges into the input stage capacitor is 6ms at low temperature, 3ms at normal temperature, and 2ms at high temperature. Therefore, the filter size is calculated at the highest precision low temperature of 6 ms: the filter size is at least 54 °. To secure sufficient margins, the filter size is designed to 90 °, with 18 ° margins left on both sides.

And the photoelectric switch is arranged outside the turntable, acquires the period information of the turntable when the turntable rotates for a period, sends the period information of the turntable to the stepping motor, and controls the stepping motor to count the rotating steps.

And the detector is used for receiving the double-color waveband infrared light information of the filter plate and converting the double-color waveband infrared light information into infrared image information.

In this embodiment, as shown in fig. 1, when the infrared thermal imaging system is in the two-color switching mode, the working method is as follows: in order to ensure that the whole integration time is within a certain filter, the window is further narrowed to 9-81 degrees. When the infrared light acquisition area is in the first optical filter or the second optical filter, and the stepping motor receives a photoelectric switch signal, counting the number of steps of the motor by N clear 0, adding 1 to N when the stepping motor moves by one step, if N is not less than 5 and not more than 15, not changing the stepping frequency, maintaining the stepping frequency, if N is more than 15, reducing the stepping frequency of the motor, and if N is less than 5, increasing the stepping frequency of the motor.

In this embodiment, as shown in fig. 2, when the infrared thermal imaging system is in the shutter compensation mode, the operation method is as follows: and the step motor enters a preset position of the shutter compensation area, and the step number of the step motor is determined according to the horizontal angle of the step motor and the rotating angle of each step number of the step motor. Specifically, it is preferable that the stepping motor enters the center position of the shutter compensation zone, and this time, the horizontal angle of the stepping motor is 135 °, that is, the number of steps of the stepping motor is 135 °/1.8 ° -75 steps.

In this embodiment, as shown in fig. 3, when the infrared thermal imaging system is in the positioning mode, the working method is as follows: and acquiring an angle theta from a position to be positioned to the photoelectric switch, clockwise rotating until the photoelectric switch is met, clearing the pedometer N of the step switch at the moment, and determining the step count of the step switch to be theta/1.8 degrees according to the angle theta and each step degree of the step switch.

According to the infrared thermal imaging system with medium-wave two-color switching, the single-color waveband of 3.7-4.8 microns of the traditional medium-wave band is divided into the narrow two-color waveband of 3.7-4.1 microns and 4.2-4.8 microns successively through the first optical filter and the second optical filter, the radiation energy of the two narrow wavebands is obtained in sequence in the time domain, and then the image information of the two wavebands is fused, so that the image acquisition of the narrow two-color waveband is realized, the anti-interference capability is high, and the image identification capability is improved. The invention only uses the stepping motor and the photoelectric switch to control the movement, and has lower cost. The invention can be used for double-color switching, shutter compensation and quick positioning, and has more complete functions.

It should be understood that the specific order or hierarchy of steps in the processes disclosed is an example of exemplary approaches. Based upon design preferences, it is understood that the specific order or hierarchy of steps in the processes may be rearranged without departing from the scope of the present disclosure. The accompanying method claims present elements of the various steps in a sample order, and are not intended to be limited to the specific order or hierarchy presented.

In the foregoing detailed description, various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments of the subject matter require more features than are expressly recited in each claim. Rather, as the following claims reflect, invention lies in less than all features of a single disclosed embodiment. Thus, the following claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

Those of skill would further appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. Of course, the storage medium may also be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. Of course, the processor and the storage medium may reside as discrete components in a user terminal.

For a software implementation, the techniques described herein may be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. The software codes may be stored in memory units and executed by processors. The memory unit may be implemented within the processor or external to the processor, in which case it can be communicatively coupled to the processor via various means as is known in the art.

What has been described above includes examples of one or more embodiments. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the aforementioned embodiments, but one of ordinary skill in the art may recognize that many further combinations and permutations of various embodiments are possible. Accordingly, the embodiments described herein are intended to embrace all such alterations, modifications and variations that fall within the scope of the appended claims. Furthermore, to the extent that the term "includes" is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term "comprising" as "comprising" is interpreted when employed as a transitional word in a claim. Furthermore, any use of the term "or" in the specification of the claims is intended to mean a "non-exclusive or".