阅读说明：本技术 用于液晶显示组件的亮度增强膜和漫射器膜 (Brightness enhancement film and diffuser film for liquid crystal display assembly ) 是由 何毅 皮波 于 2020-03-27 设计创作，主要内容包括：为在电子设备中集成的液晶模块(1720)提供了光学增强漫射器面板(2600,2700)。增强漫射器面板(2600,2700)可以用于在具有集成式光学指纹传感器(1760)的电子设备中进行背光增强和漫射。增强漫射器面板(2600,2700)包括膜层(2620,2660,2720,2760),该膜层对在一个方向上,例如,朝向显示面板,穿过的光进行折射和漫射,同时为在相反方向上,例如,朝向屏下光学传感器(1760),穿过的光提供透明的观察窗(2655)。膜层(2620,2660)可以提供背光增强和漫射,而不会模糊用于光学感测的反射探测光。(An optically enhanced diffuser panel (2600,2700) is provided for a liquid crystal module (1720) integrated in an electronic device. The enhanced diffuser panel (2600,2700) may be used for backlight enhancement and diffusion in an electronic device with an integrated optical fingerprint sensor (1760). The enhanced diffuser panel (2600,2700) includes a film layer (2620,2660,2720,2760) that refracts and diffuses light passing in one direction, e.g., toward the display panel, while providing a transparent viewing window (2655) for light passing in the opposite direction, e.g., toward the underscreen optical sensor (1760). The film layer (2620,2660) may provide backlight enhancement and diffusion without obscuring the reflected probe light for optical sensing.)

1. An integrated enhanced diffuser panel for a liquid crystal module, the panel comprising:

at least one film layer having a film surface formed thereon;

a plurality of microprismatic structures, each microprismatic structure of the plurality having a trapezoidal profile comprising a viewing surface and an enhancement surface, the viewing surface having an orientation substantially parallel relative to the film surface and the enhancement surface having an angled orientation relative to the film surface; and

a plurality of diffuser structures, each diffuser structure integrated with the enhancing surface of a respective one of the plurality of microprism structures and not integrated with the viewing surface of a respective one of the plurality of microprism structures.

2. The integrated enhanced diffuser panel according to claim 1, wherein:

at least one diffuser structure of the plurality of diffuser structures is a textured surface treatment applied to the enhancement surface of a respective one of the plurality of microprism structures for diffusing light transmitted therethrough.

3. The integrated enhanced diffuser panel according to claim 1, wherein:

at least one diffuser structure of the plurality of diffuser structures is a diffusing material applied to the enhanced surface of a respective one of the plurality of microprismatic structures for diffusing light transmitted therethrough.

4. The integrated enhanced diffuser panel according to claim 1, wherein:

the plurality of microprismatic structures defining a plurality of prismatic valley regions; and is

Each diffuser structure of at least some of the plurality of diffuser structures includes a diffusing material that fills at least a portion of a respective one of the plurality of prism valley regions.

5. The integrated enhanced diffuser panel according to claim 4, wherein for each diffuser structure of at least some diffuser structures of the plurality of diffuser structures:

the diffusing material substantially completely fills a respective one of the plurality of prism valley regions such that a top surface of the diffusing material is substantially coplanar with a viewing surface of an adjacent one of the plurality of microprismatic structures.

6. The integrated enhanced diffuser panel according to claim 4, wherein:

each of at least a portion of the plurality of prism valley regions includes a flat prism valley.

7. The integrated enhanced diffuser panel according to claim 1, wherein for each trapezoidal profile of at least some of the plurality of microprismatic structures:

the reinforcing surface is a first reinforcing surface; and is

The trapezoidal profile further includes a second enhancing surface having an angled orientation relative to the top surface, the first and second enhancing surfaces being disposed on opposite sides of the viewing surface.

8. The integrated enhanced diffuser panel according to claim 1, wherein for each trapezoidal profile of at least some of the plurality of microprismatic structures:

the reinforcing surface is a first reinforcing surface; and is

The trapezoidal profile further includes a second enhancing surface oriented substantially perpendicular with respect to the top surface, the first and second enhancing surfaces being disposed on opposite sides of the viewing surface.

9. The integrated enhanced diffuser panel according to claim 1, wherein:

each microprism structure defines a respective prismatic ridge that is flat to form a viewing surface of the microprism structure.

10. The integrated enhanced diffuser panel according to claim 1, wherein:

the at least one film layer comprises a first film layer and a second film layer;

the plurality of microprismatic structures of the first film layer form a first plurality of parallel prismatic ridges extending in a first direction; and is

The plurality of microprismatic structures of the second film layer form a second plurality of parallel prismatic ridges extending in a second direction different from the first direction.

11. The integrated reinforcing diffuser panel according to claim 10, wherein the second direction is substantially orthogonal to the first direction.

12. The integrated enhanced diffuser panel according to claim 10, wherein:

each viewing surface of the first film layer defines a respective one of the first plurality of parallel prismatic ridges; and is

Each viewing surface of the second film layer defines a respective one of the second plurality of parallel prismatic ridges,

such that a transparent viewing window is formed through each location where one of the first plurality of parallel prism ridges intersects one of the second plurality of parallel prism ridges.

13. An LCM comprising a plurality of liquid crystal module LCM layers, the plurality of LCM layers comprising:

a liquid crystal display panel having a plurality of liquid crystal structures for outputting an image for display and a plurality of touch sensing structures for detecting a touch event; and

the integrated enhanced diffuser panel of claim 1,

wherein the integrated enhanced diffuser panel is oriented with the film surface facing the liquid crystal display panel such that the plurality of microprismatic structures formed on the at least one film layer extend in the direction of the liquid crystal display panel.

14. An electronic device with an integrated underscreen optical sensor, the electronic device comprising:

a liquid crystal module LCM, the LCM comprising:

a liquid crystal display panel having a plurality of liquid crystal structures for outputting an image for display; and

an integrated reinforcing diffuser panel comprising at least one film layer having a film surface formed thereon;

a plurality of microprismatic structures, each microprismatic structure of the plurality having a trapezoidal profile comprising a viewing surface and an enhancement surface, the viewing surface having an orientation substantially parallel relative to the film surface and the enhancement surface having an angled orientation relative to the film surface; and

a plurality of diffuser structures, each diffuser structure being integrated with the enhancing surface of a respective one of the plurality of microprism structures and not integrated with the viewing surface of a respective one of the plurality of microprism structures; and

an optical sensor module disposed below the LCM for receiving probe light through the liquid crystal display panel and the integrated enhanced diffuser panel to detect optical biological features, the optical sensor module comprising an optical sensor array for receiving the probe light.

15. The electronic device of claim 14, wherein:

at least one diffuser structure of the plurality of diffuser structures is a textured surface treatment applied to the enhancement surface of a respective one of the plurality of microprism structures for diffusing light transmitted therethrough.

16. The electronic device of claim 14, wherein:

at least one diffuser structure of the plurality of diffuser structures is a diffusing material applied to the enhanced surface of a respective one of the plurality of microprismatic structures for diffusing light transmitted therethrough.

17. The electronic device of claim 14, wherein:

the plurality of microprismatic structures defining a plurality of prismatic valley regions; and is

Each diffuser structure of at least some of the plurality of diffuser structures includes a diffusing material that fills at least a portion of a respective one of the plurality of prism valley regions.

18. The electronic device of claim 14, wherein:

the at least one film layer comprises a first film layer and a second film layer;

the plurality of microprismatic structures of the first film layer form a first plurality of parallel prismatic ridges extending in a first direction; and is

The plurality of microprismatic structures of the second film layer form a second plurality of parallel prismatic ridges extending in a second direction different from the first direction.

19. The electronic device of claim 14, further comprising:

a top transparent layer disposed over the LCM for providing an output interface for displaying the image, an input interface for receiving a touch event, and an input interface for providing an optical path between the optical biometric and the liquid crystal display panel.

20. The electronic device of claim 19, further comprising:

one or more light sources below the integrated enhanced diffuser panel to project the probe light through the integrated enhanced diffuser panel and the liquid crystal display panel toward the sensor area of the top transparent layer such that a reflected portion of the probe light is received by the optical sensor module from the sensor area of the top transparent layer.

Technical Field

The present disclosure relates to liquid crystal displays, and more particularly, to brightness enhancement films and diffuser films for liquid crystal displays having an off-screen optical fingerprint sensor, for example, integrated within display panel arrangements of mobile devices, wearable devices, and other computing devices.

Background

Various sensors may be implemented in an electronic device or system to provide certain desired functionality. Sensors that enable user authentication are one example of various sensors for protecting personal data and preventing unauthorized access in various devices or systems, including portable or mobile computing devices (e.g., laptops, tablets, smartphones), gaming systems, various databases, information systems, or larger computer control systems.

User authentication on an electronic device or system may be performed through one or more forms of biometric identifiers that may be used alone or in conjunction with conventional password authentication methods. One common form of biometric identifier is a human fingerprint pattern. A fingerprint sensor may be built into an electronic device to read a fingerprint pattern of a user such that the device can only be unlocked by an authorized user of the device by authenticating the authorized user's fingerprint pattern. Another example of a sensor for an electronic device or system is a biomedical sensor in a wearable device like a wrist band device or watch, etc., which detects a biological feature of the user, e.g. blood characteristics, heartbeat of the user. In general, different sensors may be provided in an electronic device to achieve different sensing operations and functions.

Fingerprints may be used to authenticate a user for access to an electronic device, computer controlled system, electronic database or information system, as a separate authentication method or in combination with one or more other authentication methods, such as a password authentication method. For example, electronic devices and gaming systems, including portable or mobile computing devices such as laptops, tablets, smartphones, and the like, may utilize user authentication mechanisms to protect personal data and prevent unauthorized access. As another example, a computer or computer controlled device or system for an organization or enterprise should be protected to allow only authorized personnel access to protect information or use of the device or system of the organization or enterprise. The information stored in the portable devices and computer controlled databases, devices or systems may be essentially personal information such as personal contacts or phone books, personal photographs, personal health information or other personal information, or confidential information specific to an organization or business such as business financial information, employee data, business secrets and other proprietary information. If the security of accessing the electronic device or system is compromised, such data may be accessed by others, resulting in a loss of privacy or loss of valuable confidential information. In addition to the security of information, secure access to computers and computer-controlled devices or systems also allows for securing the use of devices or systems controlled by a computer or computer processor, such as computer-controlled automobiles and other systems such as ATMs.

Secure access to a device (e.g., a mobile device) or system (e.g., an electronic database and a computer controlled system) may be achieved in different ways, such as using a user password. However, passwords can be easily propagated or obtained, and this property of passwords can reduce the security level of the password. Moreover, because a user needs to remember a password when accessing a password-protected electronic device or system, if the user forgets the password, the user needs to perform some password recovery procedure to obtain authentication or otherwise regain access to the device or system. These processes can be cumbersome for the user and have various practical limitations and inconveniences. User authentication may be accomplished using personal fingerprinting to enhance data security while mitigating certain undesirable effects associated with passwords.

Electronic devices or systems, including portable or mobile computing devices, may utilize user authentication through one or more forms of biometric identifiers to protect individuals or other confidential data and prevent unauthorized access. The biometric identifier may be used alone or in combination with a cryptographic authentication method to provide user authentication. One form of biometric identifier is a fingerprint pattern of a person. Fingerprint sensors may be built into electronic devices or information systems to read a user's fingerprint pattern so that the device can only be unlocked by an authorized user of the device by authenticating the authorized user's fingerprint pattern.

Disclosure of Invention

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure. Together with the description, the drawings serve to explain the principles of the invention.

Fig. 1 is a block diagram of an example of a system having a fingerprint sensing module that may be implemented to include an optical fingerprint sensor in accordance with some embodiments.

Fig. 2A and 2B illustrate an exemplary implementation of an electronic device having a touch-sensing display screen assembly and an optical fingerprint sensor module located beneath the touch-sensing display screen assembly, according to some embodiments.

Fig. 3A and 3B illustrate examples of devices implementing the optical fingerprint sensor module illustrated in fig. 2A and 2B, according to some embodiments.

Fig. 4A and 4B illustrate an exemplary implementation of an optical fingerprint sensor module located below a display screen assembly for implementing the design shown in fig. 2A and 2B, according to some embodiments.

5A-5C illustrate signal generation of return light from a sensing region on a top sensing surface under two different optical conditions in order to understand operation of an underscreen optical fingerprint sensor module, in accordance with some embodiments.

6A-6C, 7, 8A-8B, 9, and 10A-10B illustrate example designs of an off-screen optical fingerprint sensor module according to some embodiments.

11A-11C illustrate imaging of a fingerprint sensing area on a top transparent layer by an imaging module under different tilt conditions, where the imaging device images the fingerprint sensing area onto an optical sensor array, and where the imaging device may be optically transmissive or optically reflective, according to some embodiments.

Fig. 12 is a flowchart illustrating exemplary operations of a fingerprint sensor for reducing or eliminating undesired effects from background light in fingerprint sensing, according to some embodiments.

FIG. 13 is a flow chart illustrating an exemplary process for operating an off-screen optical fingerprint sensor module to capture a fingerprint pattern in accordance with some embodiments.

14-16 illustrate exemplary operational procedures for determining whether an object in contact with an LCD display screen is part of a live human finger by illuminating the finger with light of two different light colors, in accordance with some embodiments.

Fig. 17A and 17B show cross-sections of an exemplary portable electronic device, and an exemplary display module for such a portable electronic device, respectively, in accordance with various embodiments.

Fig. 18A-18D show views of schematic portions of a conventional enhancement layer.

Fig. 19A-19C show views of schematic portions of a novel trapezoidal ridge reinforcement layer according to various embodiments.

Fig. 20A-20C show views of schematic portions of a novel trapezoidal valley enhancement layer according to various embodiments.

Fig. 21A-21C show views of schematic portions of a novel trapezoidal valley enhancement layer according to various embodiments.

Figures 22A-22E show views of schematic portions of a novel zigzag ridge enhancement layer according to various embodiments.

Fig. 23A-23C show views of schematic portions of a zigzag ridge enhancement layer of a novel trapezoidal ridge-trapezoidal valley (TRTV), in accordance with various embodiments.

FIG. 24 illustrates another embodiment of a portion of an enhancement layer representing another technique for creating flat ridges in accordance with some embodiments.

Fig. 25A and 25B show a conventional implementation of a diffuser plate.

Fig. 26A-26D show views of schematic portions of an enhancement/diffuser layer of a novel Trapezoidal Ridge Trapezoidal Valley (TRTV) in accordance with various embodiments.

Fig. 27A-27C show views of schematic portions of a zigzag ridge enhancement/diffuser layer of novel Trapezoidal Ridge Trapezoidal Valleys (TRTV), in accordance with various embodiments.

In the accompanying drawings, similar components and/or features may have the same reference numerals. In addition, various components of the same type may be distinguished by following the reference label by a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description may be applied to any one of the similar components having the same first reference label irrespective of the second reference label.

Embodiments provide an improved optically enhanced diffuser panel for liquid crystal modules integrated in electronic devices. For example, the enhanced diffuser panel may be used for backlight enhancement and diffusion in an electronic device with an integrated optical fingerprint sensor. The enhanced diffuser panel includes a film layer that refracts and diffuses light passing in one direction (e.g., toward the display panel) while providing a transparent viewing window for light passing in the opposite direction (e.g., toward the underscreen optical sensor). For example, the film layer may provide backlight enhancement and diffusion without obscuring the reflected probe light for optical sensing.