Polarized light source module and imaging device

Abstract

The embodiment of the application discloses a polarized light source module and an imaging device. The polarized light source module comprises a shell, at least one light emitting device and at least one detector arranged in a containing space in the shell. The at least one light emitting device is used for emitting polarized light with at least two different polarization angles in time. The at least one detector is used for acquiring detection signals corresponding to the polarized light with different polarization angles. The detection signals are used for characterizing the light emitting intensity of the polarized light. The arrangement can provide accurate data basis for subsequent implementation of consistency control of the light emitting intensity, thereby improving the accuracy of three-dimensional recognition depending on polarized light analysis.

Description

Technical Field

[0001] This application relates to the field of computer technology, specifically to polarization light source modules and imaging devices. Background Technology

[0002] In recent years, 3D recognition technology based on polarized light has gradually emerged. Its principle is to obtain depth information by analyzing the differences in the reflection response of a target object to light of different polarization states. This requires that the luminous intensities of different polarized light illuminating the object must be consistent. If the luminous intensities are inconsistent, the subsequent calculations of polarization differences will include errors caused by these intensity differences, leading to incorrect recognition. However, due to minor differences in manufacturing processes, component aging, temperature variations, and other factors, even two identically designed light-emitting devices may have different electro-optical conversion efficiencies, and these differences can change over time and with the environment, resulting in differences in luminous intensity.

[0003] In existing technologies, there is a lack of a real-time detection mechanism for polarized light, which makes it impossible to optimize the luminous intensity of the light source in real time. Utility Model Content

[0004] This application proposes a polarized light source module and an imaging device, which provides an accurate data basis for subsequent consistent control of light intensity, thereby improving the accuracy of 3D recognition that relies on polarized light analysis.

[0005] In a first aspect, embodiments of this application provide a polarization light source module, including a housing and at least one light-emitting device and at least one detection device disposed within the housing's internal space; the at least one light-emitting device is used to emit polarized light with at least two different polarization angles in a time-division manner; the at least one detection device is used to acquire detection signals corresponding to the polarized light with the different polarization angles, the detection signals being used to characterize the luminous intensity of the polarized light.

[0006] In some embodiments, the polarization light source module includes a light-emitting device, which includes multiple light-emitting units. Different light-emitting units are used to emit polarized light with different polarization angles. Each of the multiple light-emitting units is provided with a first electrode, and the multiple light-emitting units share the same second electrode.

[0007] In some embodiments, the polarization light source module includes multiple light-emitting devices, and different light-emitting devices among the multiple light-emitting devices are used to emit polarized light with different polarization angles.

[0008] In some embodiments, the polarization light source module includes a plurality of detection devices, each of which corresponds one-to-one with a plurality of light-emitting devices or light-emitting units. Each of the plurality of detection devices is used to acquire a detection signal when the light-emitting device or light-emitting unit corresponding to the detection device emits polarized light.

[0009] In some embodiments, the polarization light source module includes a detection device, and the plurality of light-emitting devices or light-emitting units share the detection device.

[0010] In some embodiments, the polarization light source module further includes an optical diffusion element disposed on the light emission path of the at least one light-emitting device; the at least one detection device is used to receive the light emitted by the at least one light-emitting device and reflected by the optical diffusion element.

[0011] In some embodiments, the at least one light-emitting device and the at least one detection device are respectively independently disposed at the bottom end of the housing and facing the light-emitting end of the housing, and the optical diffusion element is disposed at the light-emitting end of the housing.

[0012] In some embodiments, the at least one light-emitting device and the at least one detection device are packaged as a package body disposed at the bottom end of the housing and facing the light-emitting end of the housing, the light-emitting end of the housing is provided with a light-transmitting cover plate, and the optical diffusion element is disposed at one end of the package body facing the light-emitting end of the housing.

[0013] In some embodiments, the bottom layer of the optical diffusion element is provided with a light reflecting component, which does not coincide with the main light emission path of each of the at least one light-emitting device, and the light reflecting component is used to reflect part of the light emitted by the at least one light-emitting device to the detection device.

[0014] In some embodiments, when the polarization light source module includes a light-emitting device and a detection device, the center of the light reflection window is located at the midpoint of the line connecting the two intersection points of the first center line and the second center line on the bottom layer of the optical diffusion element. The first center line is a straight line passing through the center of the light-emitting device and perpendicular to the plane where the optical diffusion element is located, and the second center line is a straight line passing through the center of the detection device and perpendicular to the plane where the optical diffusion element is located.

[0015] In some embodiments, when the polarization light source module includes two light-emitting devices and one detection device, the detection device is located between the two light-emitting devices and at an equidistant distance from the two light-emitting devices.

[0016] Secondly, embodiments of this application provide an imaging device, including a camera module and a polarization light source module as described in any embodiment of the first aspect.

[0017] The polarization light source module provided in this application provides a crucial data foundation for subsequent consistent control of light intensity by setting at least one light-emitting device for time-division emitting at least two different polarization angles of polarized light, and setting at least one detection device to acquire detection signals of polarized light with different polarization angles in real time, thereby improving the accuracy of three-dimensional recognition that relies on polarization light analysis. Attached Figure Description

[0018] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0019] Figure 1 This is a schematic diagram of the structure of one embodiment of the polarization light source module of this application;

[0020] Figure 2 This is a schematic diagram of another embodiment of the polarization light source module of this application;

[0021] Figure 3 This is a schematic diagram of another embodiment of the polarization light source module of this application;

[0022] Figure 4 This is a schematic diagram of the structure of one embodiment of the imaging device of this application. Detailed Implementation

[0023] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the relevant utility model and not intended to limit the scope of the utility model. Furthermore, it should be noted that, for ease of description, only the parts relevant to the utility model are shown in the accompanying drawings.

[0024] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0025] Please see Figure 1 The diagram shows a structural schematic of one embodiment of the polarization light source module according to this application.

[0026] like Figure 1 As shown, the polarization light source module in this embodiment includes a housing 10 and at least one light-emitting device 101 and at least one detection device 102 disposed in the internal storage space of the housing 10.

[0027] The aforementioned at least one light-emitting device 101 is used for time-division multiplexing of polarized light with at least two different polarization angles. The light-emitting device 101 is an optical element used to generate and emit polarized light. The aforementioned at least one light-emitting device 101 can be used to time-division multiplex the emission of polarized light with at least two different polarization angles, each polarized light typically being linearly polarized. In practice, the light-emitting device 101 may include, but is not limited to, a VCSEL (Vertical Cavity Surface Emitting Laser).

[0028] As an example, the aforementioned light-emitting device 101 can emit two types of polarized light with different polarization angles in a time-division manner. The angle between the polarization angles of the two types of polarized light can be between 60 degrees and 120 degrees. This allows for a larger difference between two images acquired under polarized light with different polarization angles. When the object under test is a real three-dimensional object such as a human face, the greater the difference between the two images, the more significant the three-dimensional biological features in the difference image, thus enabling a more accurate distinction between living organisms and attacking materials.

[0029] At least one detection device 102 is used to acquire detection signals of polarized light corresponding to different polarization angles. This detection signal characterizes the luminous intensity of the polarized light and can be an electrical signal, specifically a current value, voltage value, etc.; or it can be a light intensity signal, specifically a light intensity value. In practice, the detection device 102 may include, but is not limited to, a photodiode. A photodiode is a semiconductor device that converts light signals into electrical signals, and the magnitude of its output electrical signal is proportional to the intensity of the received light signal.

[0030] Optionally, the polarization light source module includes only one light-emitting device 101. This light-emitting device 101 includes multiple light-emitting units. Different light-emitting units in the light-emitting device 101 are used to emit polarized light with different polarization angles. For example, the light-emitting device 101 may include a first light-emitting unit and a second light-emitting unit, totaling two light-emitting units. The first light-emitting unit can emit 0-degree polarized light, and the second light-emitting unit can emit 90-degree polarized light. Each light-emitting unit is provided with a first electrode, such as a negative electrode. Multiple light-emitting units share the same second electrode, such as a positive electrode. By integrating multiple light-emitting units onto a single light-emitting device, a high degree of miniaturization and compactness of the light source is achieved, making it suitable for consumer electronic devices with stringent space and power consumption requirements, such as smartphones.

[0031] Optionally, the polarization light source module may include multiple light-emitting devices 101, with different devices 101 emitting polarized light at different polarization angles. For example, the polarization light source module includes two light-emitting devices: a first light-emitting device and a second light-emitting device. The first light-emitting device emits light polarized at 0 degrees, and the second light-emitting device emits light polarized at 90 degrees. By employing multiple independent light-emitting devices, extremely high design flexibility and layout freedom are achieved. Furthermore, each light-emitting device can be procured, tested, assembled, and replaced as a standard part, reducing the cost and complexity of later maintenance.

[0032] Optionally, the polarization light source module may include multiple detection devices 102, each of which corresponds one-to-one with one of the multiple light-emitting devices 101 or multiple light-emitting units in one of the light-emitting devices 101. Each detection device 102 can be used to acquire a detection signal when the light-emitting device or light-emitting unit corresponding to it emits polarized light.

[0033] Optionally, the polarization light source module includes only one detection device 102, which is shared by the multiple light-emitting devices 101 or light-emitting units. The detection device 102 can detect the luminous intensity of each light-emitting device 101 when it emits polarized light to obtain a detection signal. By setting only one detection device in the polarization light source module, the cost of the polarization light source module is reduced, and physical space is saved.

[0034] Optionally, see Figure 1 The polarization light source module also includes an optical diffusion element 103 disposed on the light emission path of at least one of the light-emitting devices. The at least one detection device 102 can be used to receive light emitted by the at least one light-emitting device 101 and reflected by the optical diffusion element 103. Each light-emitting device 101 and the detection device 102 can be placed below the optical diffusion element 103.

[0035] The optical diffuser element 103 refers to an optical component capable of scattering incident light, thereby altering its light distribution. In practice, the optical diffuser element 103 can be a diffuser plate or a light homogenizer. Its working principle involves using internal or surface microstructures, such as microlens arrays, surface micro-roughness structures, or doped scattering particles, to cause light refraction, reflection, and diffraction, thereby converting a collimated or concentrated beam of light into a uniformly distributed light field over a larger solid angle. The optical diffuser element 103 can completely cover the light emission ports of all light-emitting devices. As the light beam emitted from the light-emitting device 101 passes through the optical diffuser element 103, a portion of the light energy changes direction on the inner surface or within the diffuser element; this portion of the light can constitute the light received by the detection device.

[0036] The optical diffuser element 103 is crucial for eye safety. If the optical diffuser element 103 detaches, the reflected light signal received by the detection device 102 will be drastically weakened. The calibration module can instantly detect the anomaly and immediately cut off the drive signal to prevent high-power-density polarized light from directly irradiating the human eye and causing eye damage.

[0037] Optionally, see Figure 1 At least one light-emitting device 101 and at least one detection device 102 are independently disposed at the bottom end of the housing 10 and facing the light-emitting end of the housing 10. An optical diffusion element 103 is disposed at the light-emitting end of the housing 10. In practice, the bottom end of the housing 10 refers to the inner surface of the internal space of the housing 10 opposite to the light-emitting end. Typically, this is also the location where the polarization light source module is mechanically and electrically connected to the motherboard of the electronic device it is located in. The fact that the light-emitting device 101 and the detection device 102 are mounted here means that they can be soldered onto a circuit board located at the bottom of the housing. Through the above arrangement, it is ensured that the light from the light-emitting device 101 reaches the optical diffusion element 103 with almost no loss and is diffused before being emitted at a designed angle, and that the detection device 102 can most effectively collect the scattered light returning from the optical diffusion element 103. This layout minimizes unnecessary and difficult-to-control optical path reflections and stray light interference.

[0038] Optionally, see Figure 2 At least one light-emitting device 101 and at least one detection device 102 are packaged into a package and disposed at the bottom of the housing 10, facing the light-emitting end of the housing 10. A light-transmitting cover plate 20 is disposed at the light-emitting end of the housing 10, and an optical diffusion element 103 is disposed at one end of the package facing the light-emitting end of the housing 10. Thus, standardized packaged components can be directly purchased or manufactured to reduce assembly difficulty and cost.

[0039] Optionally, the bottom layer of the optical diffusion element 103 may include a light-reflecting component. The light-reflecting component does not coincide with the main light-emitting path of each light-emitting device 101, and is used to reflect a portion of the light emitted by each light-emitting device 101 to the detection device 102. The main light-emitting path is the beam path with the most concentrated light energy, typically a direction perpendicular to the light-emitting plane of the light-emitting device, or within a preset angle range from the direction perpendicular to the light-emitting plane. The aforementioned portion of the light includes lower-energy residual light outside the main light-emitting path.

[0040] The bottom layer of the optical diffusion element 103 can refer to the lower surface of the optical diffusion element 103. The light reflecting component can refer to a structure with high reflectivity, such as a mirror formed by coating, or an attached metal foil, whose function is specular reflection or high-efficiency diffuse reflection.

[0041] By setting a light-reflecting component at the bottom of the optical diffusion element, the active utilization and guidance of light energy is realized, directly and effectively enhancing the intensity of the light signal received by the detection device 102. By placing the reflective component at a position that does not coincide with the main light-emitting path of the light-emitting device 101, obstruction or interference with the main light-emitting path is avoided, thus achieving light signal enhancement without affecting the main light-emitting path.

[0042] Optionally, when the polarization light source module includes a light-emitting device 101 and a detection device 102, the center of the light reflection window is located at the midpoint of the line connecting the two intersection points of the first center line and the second center line at the bottom layer of the optical diffusion element. The first center line is a straight line passing through the center of the light-emitting device 101 and perpendicular to the plane containing the optical diffusion element 103, and the second center line is a straight line passing through the center of the detection device 102 and perpendicular to the plane containing the optical diffusion element 103. Through precise design of the light reflection window's position, it can be ensured that the detection device can receive sufficiently intense reflected light, improving the accuracy and reliability of luminous intensity detection.

[0043] Optionally, see Figure 3 In the case where the polarization light source module includes two light-emitting devices 101 and one detection device 102, the detection device 102 is located between the two light-emitting devices 101 and at a distance equidistant from the two light-emitting devices 101.

[0044] It is understandable that when using a single detection device 102 to monitor two light-emitting devices 101, if the detection device 102 is close to one light-emitting device A and far from the other light-emitting device B, then even if A and B emit polarized light of the same intensity, the detection signal obtained by the detection device 102 for A will be stronger than that for B, resulting in inconsistent detection signals. Therefore, it cannot accurately reflect the difference in luminous efficacy between the two light sources. By placing the detection device 102 between the two light-emitting devices 101 at an equidistant distance, the systematic measurement error introduced by the spatial position deviation of the detection device can be minimized. This allows a single detection device to accurately detect the difference in luminous intensity between the two light-emitting devices 101, providing a highly reliable data foundation for subsequent calibration.

[0045] The calibration device provided in the above embodiments of this application, through time-division emission of the polarization light source module and real-time monitoring by the detection device, enables the calibration module to accurately calculate the differences in luminous intensity of light with different polarizations and generate calibration coefficients. During the calibration phase, the calibration module adjusts the driving signal according to the calibration coefficients, ensuring that the intensity of subsequently emitted polarized light is consistent. Through the above settings, the calibration device can dynamically eliminate or reduce the differences in luminous intensity of light with different angles of polarization caused by factors such as individual differences in light-emitting devices, aging, temperature effects, and ambient light interference, thereby improving the consistency of luminous intensity of light with different angles of polarization and thus helping to improve the accuracy of three-dimensional recognition based on polarization light.

[0046] See also Figure 4 The diagram illustrates a structural schematic of one embodiment of the imaging device of this application. The imaging device can be located in an electronic device, which may include, but is not limited to, smartphones, tablets, laptops, smart locks, facial recognition access control terminals, augmented reality / virtual reality headsets, service robots, and various IoT devices with 3D vision capabilities.

[0047] like Figure 4 As shown, the imaging device in this embodiment includes a camera module 401 and a polarization light source module 402 as described in any of the above embodiments. The camera module 401 refers to the functional module in the imaging device used for image capture. Its core components include at least a lens, an image sensor, and related driving and signal processing circuits. It should be noted that the imaging device may also include, but is not limited to, other components such as a processor, memory, display screen, and battery; these are not limited here.

[0048] In this embodiment, the camera module 401 can be used for three-dimensional imaging or polarization imaging. A polarization device, such as a polarizer, may be provided within the camera module. The camera module can receive polarized light reflected back after any of the polarized light with different polarization directions has illuminated the object under test.

[0049] The imaging device provided in this application integrates the aforementioned high-precision, monitorable polarization light source module and camera module into the same imaging device, providing a terminal product capable of achieving high-security, high-precision three-dimensional recognition, effectively solving the technical defects of existing imaging devices in terms of anti-counterfeiting capabilities and adaptability to complex environments.

[0050] This application also provides an electronic device that may include the imaging device described above. The electronic device may include, but is not limited to, smartphones, tablets, laptops, smart locks, facial recognition access control terminals, augmented reality / virtual reality headsets, service robots, and various IoT devices with 3D vision capabilities.

[0051] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the utility model involved in this application is not limited to the technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described utility model concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A polarizing light source module, characterized in that, It includes a housing and at least one light-emitting device and at least one detection device disposed within the housing's internal storage space; The at least one light-emitting device is used to emit polarized light with at least two different polarization angles in a time-division manner; The at least one detection device is used to acquire detection signals of polarized light corresponding to the different polarization angles, and the detection signals are used to characterize the luminous intensity of the polarized light.

2. The polarization light source module according to claim 1, characterized in that, The polarization light source module includes a light-emitting device, which includes multiple light-emitting units. Different light-emitting units are used to emit polarized light with different polarization angles. Each of the multiple light-emitting units is provided with a first electrode, and the multiple light-emitting units share the same second electrode.

3. The polarization light source module according to claim 1, characterized in that, The polarization light source module includes multiple light-emitting devices, and different light-emitting devices are used to emit polarized light with different polarization angles.

4. The polarization light source module according to claim 2 or 3, characterized in that, The polarization light source module includes multiple detection devices, each of which corresponds to one of the multiple light-emitting devices or light-emitting units. Each of the multiple detection devices is used to acquire a detection signal when the light-emitting device or light-emitting unit corresponding to the detection device emits polarized light.

5. The polarization light source module according to claim 2 or 3, characterized in that, The polarization light source module includes a detection device, and the multiple light-emitting devices or light-emitting units share the detection device.

6. The polarization light source module according to claim 1, characterized in that, The polarization light source module further includes an optical diffusion element disposed on the light emission path of the at least one light-emitting device; the at least one detection device is used to receive the light emitted by the at least one light-emitting device and reflected by the optical diffusion element.

7. The polarization light source module according to claim 6, characterized in that, The at least one light-emitting device and the at least one detection device are respectively independently disposed at the bottom end of the housing and facing the light-emitting end of the housing, and the optical diffusion element is disposed at the light-emitting end of the housing.

8. The polarization light source module according to claim 6, characterized in that, The at least one light-emitting device and the at least one detection device are encapsulated in a package body disposed at the bottom end of the housing and facing the light-emitting end of the housing. A light-transmitting cover plate is disposed at the light-emitting end of the housing, and the optical diffusion element is disposed at one end of the package body facing the light-emitting end of the housing.

9. The polarization light source module according to any one of claims 6-8, characterized in that, The bottom layer of the optical diffusion element is provided with a light reflecting component. The light reflecting component does not coincide with the main light emission path of each of the at least one light-emitting device. The light reflecting component is used to reflect part of the light emitted by the at least one light-emitting device to the detection device.

10. The polarization light source module according to claim 9, characterized in that, In the case where the polarization light source module includes a light-emitting device and a detection device, the center of the light reflection window is located at the midpoint of the line connecting the two intersection points of the first center line and the second center line on the bottom layer of the optical diffusion element. The first center line is a straight line passing through the center of the light-emitting device and perpendicular to the plane where the optical diffusion element is located, and the second center line is a straight line passing through the center of the detection device and perpendicular to the plane where the optical diffusion element is located.

11. The polarization light source module according to any one of claims 1, 3, 6-8, characterized in that, In the case where the polarization light source module includes two light-emitting devices and one detection device, the detection device is located between the two light-emitting devices and at an equidistant position from the two light-emitting devices.

12. An imaging device, characterized in that, It includes a camera module and a polarizing light source module as described in any one of claims 1 to 11.

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