Light source device, imaging device, and display device
By decomposing the source image signal into multiple subframes and controlling the spot shift, the problems of low energy utilization efficiency and insufficient dynamic contrast in the existing imaging solutions are solved, and efficient and uniform image display is achieved.
Patent Information
- Application Number
- CN202010705924.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2020-07-21
- Publication Date
- 2025-06-20
- Estimated Expiration
- 2040-07-21
AI Technical Summary
The existing imaging schemes based on spatial light modulators have problems such as low energy utilization efficiency, large volume, low energy efficiency, and difficulty in obtaining high brightness and high dynamic contrast.
By decomposing the source image signal into sparsely sampled multiple subframes, and controlling the spot shifting device according to timing, the spot position emitted by the light source array module corresponds to each subframe in sequence.
The modulation bandwidth of the light source device and the control bandwidth of the spot shifting device are reduced, the image uniformity is improved, and the speckle of the image is weakened in the case of a laser light source, achieving high contrast and high dynamic range.
Smart Images

Figure CN113960865B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of optical information processing technologies, and particularly to a light source device, an imaging device, and a display device. Background Art
[0002] In technologies such as object 3D imaging and projection display, it is usually necessary to form image light according to a source image by using an imaging system including a light source, a spatial light modulator, a projection lens, etc. to reproduce the source image, which is herein referred to as an imaging technology. Common imaging technology solutions include an imaging solution based on a spatial light modulator, an imaging solution based on beam scanning, etc.
[0003] Existing imaging solutions based on a spatial light modulator generally include a solution based on DMD (Digital Micromirror device), a solution based on LCD (Liquid Crystal Display), and a solution based on LCOS (Liquid Crystal on Silicon).
[0004] Solution based on DMD: In digital light processing (DLP) display technology, an image is generated by a DMD. The DMD is a spatial light modulator, which is a matrix composed of micromirrors (precision, miniature mirrors) arranged on a semiconductor chip. Each micromirror controls a pixel in the projection screen, and the number of micromirrors matches the resolution of the projection screen. The light source projects onto the DMD, and the micromirrors can quickly flip under the drive of a digital signal, existing in on (on) and off (off) states. The lens only receives the light in the on state, and different grayscales are obtained by controlling the switch state, thereby obtaining a color image.
[0005] Solution based on LCD: In an LCD liquid crystal display, a liquid crystal cell is placed between two parallel glass substrates. A TFT (thin film transistor) is provided on the lower substrate glass, and a color filter is provided on the upper substrate glass. The rotation direction of the liquid crystal molecules is controlled by changing the signal and voltage on the TFT, so as to control the polarization light emission state of each pixel point to obtain a gray scale and achieve color imaging. Its principle is to utilize the birefringence of liquid crystal molecules. Through a certain arrangement of liquid crystal molecules (commonly nematic), under the action of different current electric fields, the liquid crystal molecules will regularly rotate by 90 degrees, resulting in a difference in light transmittance for the incident polarized light, realizing the conversion between on and off states and achieving the imaging purpose.
[0006] LCOS-based solution: LCOS belongs to a new type of reflective Micro LCD (micro LCD) projection technology. Its structure is to fabricate a driving panel (also known as CMOS-LCD) on a silicon wafer using semiconductor processes, then deposit aluminum on the transistors as a mirror to form a CMOS substrate. Then, the CMOS substrate is bonded to an upper glass substrate containing transparent electrodes, and liquid crystal is injected. Its basic principle is similar to that of LCD, both using the birefringence principle of liquid crystal molecules. When the voltage of the aluminum electrodes on the silicon substrate changes, the liquid crystal voltage changes, and the liquid crystal molecules deflect, realizing the modulation of the on and off states of the incident polarized light and generating an image.
[0007] Existing imaging solutions based on spatial light modulators (such as DMD, LCD, or LCOS) modulate the light intensity of the image light through the spatial light modulator to achieve the display of different gray levels and colors. The energy utilization efficiency of the spatial light modulator is very low. For example, the off-light of DMD cannot be utilized, and LCD or LCOS modulates the polarization state distribution of the transmitted light through the deflection of liquid crystal molecules, and the excess light is absorbed by the polarization devices. These spatial light modulators all have large energy losses, so a relatively strong heat dissipation system is also required. The overall volume of the light source device, imaging device, or display device based on the spatial light modulator is large and the energy efficiency is low. In addition, due to the limitation of the heat dissipation of the spatial light modulator device itself, it cannot carry a high energy density, so it is difficult to obtain a very high-brightness display. Due to the limitation of the spatial light modulator itself, such as the leakage of off-light of DMD, the conversion of the polarization state of the light beam by liquid crystal molecules, and the polarization film all have a certain conversion efficiency, resulting in the difficulty of obtaining a high dynamic contrast for the resulting image.
[0008] The imaging solution based on beam scanning generally mainly uses a laser as the light source, modulates the light source through a light modulator, and realizes display imaging through a two-dimensional scanner, an optical color combining system, and a projection objective lens. The source image signal is loaded onto the light modulator to control the intensity of the light beam; at the same time, the signals of the row and field are synchronized to the light deflector, so that the light beam is projected onto the screen or other targets at a modulated intensity according to a certain rule to form a color image.
[0009] Existing beam scanning imaging solutions mainly use a laser as the main light source and use a light modulator to modulate the light intensity of the light beam. Common light modulators include electro-optic modulation and acousto-optic modulation. After the three-color laser passes through the modulator loaded with the video signal, it becomes laser beams with different light intensities carrying the video signal, and then passes through the color combining system of the optical thin film to synthesize a beam of light. Then it enters the X-Y scanning system. This scanning system generally uses a combination of a rotating mirror and a small-angle galvanometer mirror, or a double rotating mirror system or a double galvanometer mirror to achieve.
[0010] The beam scanning imaging scheme uses an optical modulator, resulting in a relatively large power consumption and volume of the system; due to the small number of laser light sources used, it has high requirements for the control bandwidth of the modulator and the scanning device, with a relatively low image resolution, a small field of view obtained, and a strong speckle effect. Summary of the Invention
[0011] Embodiments of the present application provide a light source device, which includes a light source array module, a control module, and a spot shifting device, where:
[0012] The light source array module includes a plurality of light sources arranged in an array. Among them, the light beam emitted by each light source in the plurality of light sources forms a spot corresponding to one pixel of a frame of target image. The target image includes a plurality of pixels and is composed of a plurality of sub - frames. Among them, each sub - frame contains a part of the plurality of pixels, and the pixels contained in the plurality of sub - frames together form the plurality of pixels;
[0013] The spot shifting device is used to move the positions of the spots of the plurality of light sources under the control of the control module;
[0014] The control module is configured to control the spot shifting device in sequence so that the positions of the spots of the plurality of light sources correspond to each sub - frame in turn. Among them, the control module is configured to: control the spot shifting device according to the pixel positions of each sub - frame, so that at the moment corresponding to the sub - frame, the positions of the spots of the plurality of light sources correspond one - to - one with the positions of the pixels contained in the sub - frame. Among them, at least one pixel of other sub - frames is interposed between at least two adjacent pixels of each sub - frame.
[0015] Embodiments of the present application further provide an imaging device, including the light source device as described above.
[0016] Embodiments of the present application further provide a display device, including the light source device as described above.
[0017] Embodiments of the present application further provide an imaging method, including:
[0018] Decompose a frame of target image to obtain a plurality of sub - frames, where at least one pixel of other sub - frames is interposed between at least two adjacent pixels of each sub - frame;
[0019] According to the pixel positions of each sub - frame, move the positions of the spots emitted by the light source array module in sequence through the spot shifting device, so that the positions of the spots correspond to each sub - frame in turn;
[0020] Image the spots corresponding to the plurality of sub - frames emitted by the light source array module to obtain image light,
[0021] Among them, the light source array module includes a plurality of light sources. The light beam emitted by each light source in the plurality of light sources forms a light spot corresponding to one pixel of the target image. At the moment corresponding to the sub-frame, the positions of the plurality of light spots formed by the plurality of light sources correspond one-to-one to the positions of the plurality of pixels included in the sub-frame.
[0022] Through the above embodiments of the light source device, imaging device, display device, and imaging method, the beneficial effects of the present application are as follows:
[0023] By decomposing the target image in the source image signal into a plurality of sub-frames with sparse sampling, and sequentially forming light spots corresponding to each sub-frame according to the time sequence. Among them, when switching from one sub-frame to the next sub-frame, the position of the light spot is moved by the light spot shifting device to correspond to the pixel position of the corresponding sub-frame, so that within the time of displaying one frame of image, the light spot corresponding to each light source is moved to correspond to a plurality of image pixel points. Since the overall resolution is achieved by a light source array including a plurality of light sources, and each light source can be modulated separately to contribute to the overall resolution. Therefore, compared with a single light source contributing to the overall resolution, the modulation bandwidth of the light source device in the embodiments of the present application is reduced. In addition, since the light spot corresponding to a single light source only needs to cover a certain area in the overall image, the control bandwidth of the light spot shifting device can be effectively reduced in the embodiments of the present application. In addition, since a certain area in the overall image is formed by moving a single light source, the image uniformity can be effectively improved in the embodiments of the present application. In addition, the embodiments of the present application use a light source array as the light source. When the light source is a laser, the moving light spot scheme can also effectively reduce the speckle of the formed image.
[0024] In addition, in some embodiments of the present application, the two-dimensional gray scale distribution of each sub-frame is realized by adjusting the brightness of each light source during its corresponding time period, avoiding the use of a currently less efficient spatial light modulator. Therefore, the efficiency of the light source device, imaging device, display device, or imaging method can be greatly improved. In addition, since the brightness of a single pixel can be fully turned on / fully turned off by adjusting the brightness of the light source, these embodiments can achieve high contrast and high dynamic range.
[0025] In addition, in some embodiments, each light source of the light source array module is independently addressable, that is, independently controllable. Therefore, variable optical coding can be realized, thereby improving the imaging accuracy. In addition, in the case where each light source is independently controllable, the gray scale of a single pixel can be realized by modulating the light intensity of the corresponding single light source. The adjustment method is simple and easy. In addition, since the brightness of a single pixel can be fully turned on / fully turned off by adjusting the brightness of the light source, these embodiments can achieve high contrast and high dynamic range. The dot matrix or structured light generated by using this scheme can be quickly transformed to generate customized patterns at an extremely high speed. Description of the Drawings
[0026] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings. Among them:
[0027] Figure 1 is a schematic structural diagram of a light source device according to an embodiment of the present application;
[0028] Figure 2 is a schematic diagram of how to decompose a target image frame into multiple sub - frames according to an embodiment of the present application;
[0029] Figure 3 is a schematic diagram of the array light sources of a light source array module and the closely - packed pixel array formed by using the array light sources according to an embodiment of the present application;
[0030] Figure 4 is a schematic structural diagram of a light source device according to another embodiment of the present application;
[0031] Figure 5 is a schematic structural diagram of a light source device according to yet another embodiment of the present application;
[0032] Figure 6 is a schematic flowchart of an imaging method according to an embodiment of the present application;
[0033] Figure 7 is a schematic diagram of a 3D imaging scheme based on a light source array according to an embodiment;
[0034] Figure 8 is a schematic diagram of a MEMS - based VCSEL light source array system according to an embodiment;
[0035] Figure 9 is a schematic structural block diagram of an imaging device according to an embodiment of the present application;
[0036] Figure 10 is a schematic structural diagram of an imaging device according to another embodiment of the present application;
[0037] Figure 11 is Figure 10 a schematic diagram of the pulse signal and displacement curve in the shown embodiment;
[0038] Figure 12 is a schematic structural diagram of an imaging device according to another embodiment of the present application;
[0039] Figure 13 is a schematic structural diagram of a display device according to an embodiment of the present application;
[0040] Figure 14 is a schematic structural diagram of a display device according to another embodiment of the present application;
[0041] Figure 15 is a schematic structural diagram of a display device according to still another embodiment of the present application;
[0042] Figure 16 is a schematic diagram of a Micro LED combined light source according to an embodiment of the present application;
[0043] Figure 17 is related to Figure 2 a frame splitting schematic diagram for an example image corresponding to the frame splitting method shown. Detailed implementation manners
[0044] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts belong to the scope of protection of the present application.
[0045] In the present application, terms such as "imaging technology", "imaging method", or "imaging" in the above and below refer to a process, method, or technology of using a light source and optoelectronic devices to form image light corresponding to a source image to reproduce the source image.
[0046] In the present application, terms such as "image", "source image", "image signal", etc. in the above and below include images and / or videos in any form or format.
[0047] In the present application, terms such as "sub-frame time", "time corresponding to a sub-frame", etc. in the above and below refer to the time to display the sub-frame and the time to form a light spot corresponding to the pixels of the sub-frame.
[0048] Figure 1 shows a schematic structural diagram of a light source device 100 according to an embodiment of the present application. As Figure 1 shown, in this embodiment, the light source device 100 includes a light source array module 110, a control module 120, and a light spot shifting device 130. The light source array module 110 includes a plurality of light sources 111 arranged in an array form. Among them, the light beam emitted by each light source 111 forms a light spot 112 corresponding to a pixel of a frame of target image (see Figure 3) That is, one pixel in the target image corresponds to one light spot of the light source beam. If the number of light sources is large enough, for example, the number of light sources is equal to or greater than the number of pixels in the target image, it is not necessary to decompose the target image into multiple sub-frames, and the target image can be completely displayed at once by forming light spots equal in number to the number of pixels in the target image. However, in the case where the number of light sources is less than the number of pixels included in the target image, it is necessary to decompose the target image into multiple sub-frames and sequentially display the multiple sub-frames in a time-sharing manner within an extremely short time. The number of pixels included in each sub-frame displayed each time is equal to or less than the number of light sources, that is, the resolution of the sub-frame is equal to or less than the light source resolution of the light source array module 110. Each of the multiple sub-frames that make up a frame of the target image includes a part of the pixels included in the target image, and the set of pixels included in all sub-frames is equal to all the pixels included in the target image. Since the time for displaying multiple sub-frames is short enough, the human eye cannot perceive the switching between different sub-frames due to the persistence of vision phenomenon, and the human eye will automatically splice multiple sub-frames into a complete image within one frame.
[0049] In the embodiments of the present application, the number of pixels included in the target image is greater than the number of light sources included in the light source array module 110. The target image in the embodiments of the present application includes multiple pixels and is composed of multiple sub-frames. Among them, each sub-frame included in the multiple sub-frames includes a part of the multiple pixels included in the target image, and the pixels included in the multiple sub-frames together constitute the pixels included in the target image. In the embodiments of the present application, these sub-frames are sparsely sampled, at least one pixel of other sub-frames is interposed between at least two adjacent pixels of each sub-frame, the number of pixels included in each sub-frame is equal to or less than the number of light sources included in the light source array module, and the pixel positions of each sub-frame are different. In one example, one or more pixels of one or more other sub-frames are interposed between every two adjacent pixels included in each sub-frame.
[0050] The light spot shifting device 130 is configured to move the position of the light spot 112 emitted by the light source 111 of the light source array module 110 under the control of the control module 120. The control module 120 is configured to control the light spot shifting device 130 according to a time sequence, so that the position of the overall light spot emitted by the light source array module 110 corresponds to each sub-frame in sequence. To achieve the position of the light spot corresponding to each sub-frame in sequence, in one example, the control module 120 may be configured to: control the light spot shifting device 130 according to the pixel position of each sub-frame, so that at the moment corresponding to the sub-frame, the positions of the multiple light spots 112 of the light source array module 110 correspond one by one to the positions of the multiple pixels included in the sub-frame.
[0051] For example, assume that the target image includes four sub-frames S1 - S4, and the time T for displaying the target image is divided into four equal sub-frame periods T1 - T4. Among them, sub-frame S1 is displayed at time t1, sub-frame S2 is displayed at time t2, sub-frame S3 is displayed at time t3, and sub-frame S4 is displayed at time t4. As described above, sub-frames S1 - S4 are sparsely sampled, the number of pixels included in each sub-frame is equal to the number of light sources 111 included in the light source array module 110, and each of the sub-frames S1 - S4 has different pixel positions. In an embodiment of the present application, at time t1, the control module 120 controls the spot shifting device 130 to shift the position of the spot 112 emitted by the light source array module 110 to the position corresponding to the pixels of sub-frame S1, that is, to make the pixel position of the image light formed by the spot 112 consistent with the position of the pixels included in sub-frame S1. In this embodiment, when the spot shifting device 130 shifts the spot 112 emitted by the light source array module 110 to the position corresponding to sub-frame S1, the position of each spot 112 corresponds to the position of the pixel in sub-frame S1 corresponding to it. At time t2, the spot shifting device 130 controlled by the control module 120 shifts the spot 112 emitted by the light source array module 110 to the position corresponding to the pixels of sub-frame S2. From displaying one sub-frame to displaying the next sub-frame, the spot shifting device 130 moves the spot 112 by a distance corresponding to the pixel pitch between two sub-frames. For example, assume that each pixel of sub-frame S2 is translated one pixel to the right relative to each pixel of sub-frame S1, then the control module 120 controls the spot shifting device 130 to translate the spot 112 emitted by the light source array module 110 as a whole to the right by a distance corresponding to one pixel of the image light. At times t3 and t4, the spot shifting device 130 continues to move the spot 112 so that it corresponds to the positions of sub-frames S3 and S4 respectively. Thus, within time T, the light source device 100 sequentially emits spots corresponding to sub-frames S1 - S4 in sequence. Due to the visual persistence phenomenon of the human eye, these four sub-frames constitute the reproduction of a complete target image in the human eye.
[0052] In the examples described above and below in this text, the distance between the corresponding pixels of two adjacent sub-frames is the same. For example, in the example described above, the distance between each pixel in S2 and the corresponding pixel in S1 is one pixel. In this way, all spots can be moved as a whole when moving the spots. It can be understood that the distance between the corresponding pixels of two adjacent sub-frames can also be different. When transitioning from one sub-frame to the next sub-frame, the distance to be moved can be determined for each spot, and the spot shifting device 130 can be controlled to shift each spot or each part of the spots with the same moving distance respectively.
[0053] In the examples described above and below in this article, the intervals between every two adjacent light sources 111 of the light source array module 110 are equal. Therefore, the intervals between the adjacent light spots emitted by them are also equal. It can be understood that the intervals between adjacent light sources can be different, and the distances between adjacent light spots can also be different.
[0054] Figure 2 FIG. shows a schematic diagram of how to decompose a frame of target image into multiple sub-frames according to an embodiment of the present application. In the embodiment of the present application, how to decompose the target image into multiple sub-frames can be determined according to factors such as the number of pixels of the target image, the number of light sources included in the light source array module, and the intervals between the light sources. In one example, assume that multiple light sources of the light source array module 110 form an M×N array (both M and N are greater than 1), and the light spots emitted are also an M×N array (as Figure 3 shown), the target image S includes X×Y pixels (X is greater than M, Y is greater than N), then the target image S can be decomposed into a×b sub-frames, where, a = X / M, b = Y / N. In Figure 2 the example, the light source array module 110 is a 3×3 light source array, and the number of pixels included in the target image is 6×6, then the target image S can be decomposed into 2×2 sub-frames S1 - S4.
[0055] In the embodiment of the present application, the density of the array formed by arranging multiple light sources 111 of the light source array module 110 is less than the density of the pixel distribution of the target image. The array formed by arranging multiple light sources 111 is a sparse dot matrix relative to the pixel distribution of the target image. That is, the multiple light spots emitted by the light source 111 are imaged corresponding to non-adjacent pixels with one or more other pixels in between, rather than multiple adjacent pixels of the image. In Figure 2 the example, assume that the interval between every two adjacent light sources 111 is such that the pixels formed after imaging the light spots emitted by two adjacent light sources 111 are separated by 1 pixel. Then the positions of the four sub-frames S1 - S4 decomposed from the target image S in the target image S are as Figure 2 shown. In Figure 2 each square represents a pixel, and the number in the square represents the sub-frame number to which the pixel belongs. For example, the number "1" represents the sub-frame S1, the number "2" represents the sub-frame S2, the number "3" represents the sub-frame S3, and the number "4" represents the sub-frame S4. In Figure 2In the example, the target image S is decomposed into four sub-frames S1 - S4 shown in chronological order, where each sub-frame is spaced one pixel distance from the next sub-frame. After displaying sub-frame S1 at time t1, at time t2, the control module 120 controls the spot shifting device 130 to shift the spot 112 emitted by the light source array module 110 as a whole to the right by a distance corresponding to one pixel of the image light to form sub-frame S2; at time t3, the control module 120 controls the spot shifting device 130 to shift the spot 112 emitted by the light source array module 110 as a whole downward by a distance corresponding to one pixel of the image light and then continue to shift it to the right by a distance corresponding to one pixel of the image light to form sub-frame S3; at time t4, the control module 120 controls the spot shifting device 130 to shift the spot 112 emitted by the light source array module 110 as a whole to the right by a distance corresponding to one pixel of the image light to form sub-frame S4. In Figure 2 In the example, the four sub-frames are displayed in the order of S1 → S2 → S3 → S4. It can be understood that the four sub-frames can also be displayed in other orders, and finally the reproduction of the complete target image can be obtained. In Figure 2 In the example, the pixels of sub-frames S1 - S4 are arranged together as closely packed pixels. Through the embodiments of the present application, a sparse array light source can be effectively projected into a high-resolution implementation scheme, and a sparse light source array arranged in M*N can be scanned into aM*bN closely packed equidistant spots, as Figure 3 shown in.
[0056] In the embodiments of the present application, when the control module 120 controls the spot shifting device 130 to shift the spot 112 emitted by the light source array module 110 to correspond to the position of each sub-frame, it also controls the brightness of each light source 111 of the light source array module 110 according to the gray-scale distribution of each sub-frame, so that at the moment corresponding to the sub-frame, each spot of the light source 111 forms the gray-scale display of the corresponding pixel of the sub-frame. For example, the control module 120 can adjust the brightness of the light source 111 by adjusting or modulating the drive current or drive voltage of the light source 111. In the embodiments of the present application, each pixel of the image light corresponds one-to-one to each spot 112 emitted by the light source array module 110, and each spot 112 is emitted by only one light source. Therefore, each pixel of the image light is only related to the corresponding one light source and has nothing to do with other light sources. In one example, each light source 111 can be independently controlled or driven, and the gray level of each pixel of the formed image light is only related to the corresponding unique light source. The control module 120 can independently control the brightness of each light source 111 of the light source array module 110, thereby controlling the pixel gray level of the formed image.
[0057] According to the light source device of the embodiments of the present application, a target image in a source image signal is decomposed into a plurality of sub-frames with sparse sampling (that is, at least one pixel of other sub-frames is interposed between at least two adjacent pixels of each sub-frame). The pixels of each sub-frame correspond one by one to the light sources of the light source array module, and light spots corresponding to each sub-frame are sequentially formed according to a time sequence. Among them, when switching from one sub-frame to the next sub-frame, the position of the light spot is moved by a light spot shifting device so that it corresponds to the pixel position of the corresponding sub-frame. During the time of displaying one frame of image, the light spots corresponding to each light source are moved to correspond to a plurality of image pixel points. Since the overall resolution is achieved by a light source array including a plurality of light sources, and each light source can be modulated separately to contribute to the overall resolution, compared with a single light source contributing to the overall resolution, the embodiments of the present application reduce the modulation bandwidth of the light source device. In addition, since the light spot corresponding to a single light source only needs to cover a certain area in the overall image, the embodiments of the present application can effectively reduce the control bandwidth of the light spot shifting device. In addition, since a certain area in the overall image is formed by moving a single light source, the embodiments of the present application can effectively improve the image uniformity. In addition, the embodiments of the present application use a light source array as the light source. When the light source is a laser, the moving light spot scheme can also effectively weaken the speckle of the formed image.
[0058] As described above, in some embodiments of the present application, the two-dimensional gray-scale distribution of each sub-frame is realized by adjusting the brightness of each light source during its corresponding time period, avoiding the use of a currently less efficient spatial light modulator. Therefore, the efficiency of the light source device can be greatly improved. In addition, since the brightness of a single pixel can be fully turned on / fully turned off by adjusting the brightness of the light source, these embodiments can achieve high contrast and high dynamic range.
[0059] In addition, in some embodiments, each light source of the light source array module is independently addressable, that is, independently controllable. Therefore, variable optical coding can be realized, thereby improving the imaging accuracy. In addition, when each light source is independently controllable, the gray level of a single pixel can be realized by modulating the light intensity of the corresponding single light source. The adjustment method is simple and easy to implement. In addition, since the brightness of a single pixel can be fully turned on / fully turned off by adjusting the brightness of the light source, these embodiments can achieve high contrast and high dynamic range. The dot matrix or structured light generated by this scheme can be quickly transformed to generate a customized pattern at an extremely high speed.
[0060] Figure 4 Fig. shows a schematic structural diagram of a light source device 100 according to another embodiment of the present application. In Figure 4 the embodiment of, different from the embodiment of Figure 1 is that the control module 120 may include the following three parts: a processor 121, a light source driver 122, and a light spot shift control unit 123, where:
[0061] The processor 121 is configured to perform image processing on the received source image signal to obtain a target image including a plurality of sub - frames. The image processing performed by the processor 121 may include one or more of format conversion, decoding, filtering, amplification, etc. on the received source image signal, and may also include obtaining the target image from the source image signal and decomposing the target image into a plurality of sub - frames that match the light source device 100 according to the number of pixels of the target image and the configuration parameters of the light source device 100. The configuration parameters of the light source device 100 may include the number of light sources and the interval of the light source array module 110, etc. The processor 121 sends the decomposed sub - frame signals and the corresponding timing of each sub - frame to the light source driver 122 and the spot shift control unit 123.
[0062] The light source driver 122 is configured to generate a signal for driving the light source array module 110 to emit light according to the signals of a plurality of sub - frames. In one example, the light source driver 122 generates a corresponding drive signal for the light source 111 corresponding to each pixel according to the gray level of each pixel of each sub - frame, and the drive signal makes the brightness of the light emitted by the light source 111 consistent with the gray level of the pixel. In this way, the light source driver 122 can drive the light source 111 to generate spots with corresponding brightness for each sub - frame at the moment of each sub - frame. In some examples, when the number of spots required for a sub - frame is less than the number of light sources, some light sources may not emit light, that is, the light source driver 122 does not generate a drive signal for them.
[0063] The spot shift control unit 123 is configured to generate a signal for controlling the spot shift device 130 to move the spot 112 according to the signals of a plurality of sub - frames. For example, the spot shift control unit 123 controls the spot shift device 130 to move each spot formed by the light source array module 110 to correspond one - to - one with the positions of the pixels of the sub - frame at the moment of each sub - frame.
[0064] The spot shift device 130 moves the positions of the spots formed by the light source array module 110 according to the instructions from the control module 120 or the spot shift control unit 123, so that at the moment of each sub - frame, the positions of the spots formed by the light source array module 110 correspond one - to - one with the positions of the pixels of the sub - frame. In the above and below of this application, "the moment of each sub - frame" refers to the moment when each sub - frame is reproduced according to the timing, that is, the moment when the spot corresponding to the sub - frame is formed. At this moment, the corresponding spot is moved to the position corresponding to the sub - frame, and the brightness of each spot is consistent with the gray level of the pixels of the sub - frame.
[0065] In one example, the spot shifting device 130 can change the position of the spot 112 by moving the position of the light source 111 of the light source array module 110. For example, the spot shifting device 130 is a two-dimensional micro actuator capable of moving in a first direction and a second direction perpendicular to each other. Alternatively, the spot shifting device 130 is a combination of two one-dimensional micro actuators, the first one-dimensional micro actuator being capable of moving in the first direction and the second one-dimensional micro actuator being capable of moving in the second direction. The light source 111 of the light source array module 110 can be attached to the above-mentioned micro actuator, and the micro actuator moves under the instruction of the control module 120 or the spot shifting control unit 123, thereby driving the movement of the light source 111 and thus changing the position of the light source 111. The light source 111 of the light source array module 110 can be fixed as a whole to a two-dimensional micro actuator or two one-dimensional micro actuators, and the movement of the micro actuator can drive the overall movement of the light source array module 110. Alternatively, the light source array module 110 can be divided into multiple parts, each part including one or more light sources 111, and each part is respectively fixed to a two-dimensional micro actuator or two one-dimensional micro actuators. The two-dimensional micro actuator can be a two-dimensional deflection stage, and the one-dimensional micro actuator can be a high-frequency piezoelectric ceramic actuator, a piezoelectric moving platform, a piezoelectric stepping motor or a one-dimensional deflection stage. The micro actuator can be in a linear motion, a deflection motion or other motion forms. The movement speeds of the two-dimensional micro actuator in the two directions can be the same or different. For example, the movement in the first direction is faster than the movement in the second direction. Alternatively, the movement speeds of the two one-dimensional micro actuators can be the same or different. For example, the one-dimensional micro actuator moving in the first direction is faster than the one-dimensional micro actuator moving in the second direction.
[0066] In another example, the spot shifting device 130 can change the position of the spot 112 by deflecting the propagation direction of the light beam emitted by the light source array module 110. For example, the light beam deflecting device is a MEMS scanning mirror or a phase deflecting device.
[0067] In one embodiment of the present application, to ensure the consistency between the movement of the light spot position and the adjustment of the light spot brightness, the control module 120 may further include a synchronization unit 124. The synchronization unit 124 is configured to synchronize the light source driver 122 and the light spot shifting device 130 according to multiple sub-frames, so that while the light spot shifting device 130 moves the light spots 112 of the multiple light sources 111 to positions corresponding to each sub-frame among the multiple sub-frames, the light source driver 122 drives the light source array module 110 to emit light corresponding to the gray-scale distribution of the sub-frame. The synchronization unit 124 is connected to the processor 121, the light source driver 122, and the light spot shifting control unit 123. The control module 120 may send each sub-frame and the corresponding timing to the synchronization unit 124. In one example, the synchronization unit 124 may ensure, according to the timing of each sub-frame, that the light spot shifting control unit 123 drives the light spot shifting device 130 to be synchronized with the light source driver 122 driving the light source 111 to emit light, so that while the light spot shifting device 130 drives the light spot to shift to a position corresponding to each sub-frame, each light source 111 emits light under the drive of the light source driver 122, and the brightness of the emitted light spot 112 is consistent with the gray scale of each pixel of the sub-frame. The synchronization unit 124 can ensure that the light source 111 does not emit light in advance or delay, but emits light with the corresponding brightness while the light spot shifts to the target position.
[0068] In one example, the light source 111 is a laser light source, and the light source driver 122 emits a pulse drive signal to drive the light source 111 to emit light. In one example, the synchronization unit 124 is configured to control the timing of the pulse driving the laser light source 111 and the movement of the light spot shifting device 130, so that the laser light source 111 emits equally spaced light spots along with the movement of the light spot shifting device 130.
[0069] In Figure 4 the embodiment, the control module 120 is divided into four functional modules: a processor 121, a light source driver 122, a light spot shifting control unit 123, and a synchronization unit 124. It can be understood that this division is a logical division according to functions, and the control module 120 can also be divided into other different logical functional modules, and the number of functional modules divided can be more or less.
[0070] The light source 111 can be various light source devices capable of emitting light. For example, each light source 111 can be a vertical cavity surface emitting laser, an edge emitting laser, an LED, or a Micro LED, etc.
[0071] In the above embodiment, the light spot emitted by each light source 111 of the light source array module 110 can be a monochromatic light spot or a white light spot.
[0072] Figure 5FIG. 0 shows a schematic structural diagram of a light source device 100 according to another embodiment of the present application. As Figure 5 shown, the difference between this embodiment and the embodiment shown in Figure 1 is that the light source array module 110 may include a first light source array module 110A, a second light source array module 110B, and a third light source array module 110C. Among them, the first light source array module 110A includes a plurality of first light sources 111A that emit light of a first color, the second light source array module 110B includes a plurality of second light sources 111B that emit light of a second color, and the third light source array module 110C includes a plurality of third light sources 111C that emit light of a third color. For example, the first color, the second color, and the third color may be blue, green, and red, respectively. In one example (as shown in Figure 4 ), the light source device 100 may further include a light combining module 140. The three light source array modules have an equal number of light sources. Three light spots of three colors emitted by each first light source 111A and a corresponding second light source 111B and a corresponding third light source 111C can be combined into a white light spot by the light combining module 140 as the imaging light. In this way, three monochromatic light spot arrays emitted by the three light source array modules are finally combined into a mixed-color light spot array by the light combining module 140, such as a white light spot array. In another example, the light source device 100 may not have a light combining module 140. Each first light source 111A and a corresponding second light source 111B and a corresponding third light source 111C may be arranged as three sub-pixels closely adjacent to each other at the same position, so that the light spots emitted by the three light sources appear to be emitted from the same position and correspond to the same pixel of the imaging light. In this case, the light combining module 140 may not be used.
[0073] In Figure 5 the embodiment shown, the light spot shifting device 130 may correspondingly include a first light spot shifting device 130A for shifting the light spots of the first light source array module 110A, a second light spot shifting device 130B for shifting the light spots of the second light source array module 110B, and a third light spot shifting device 130C for shifting the light spots of the third light source array module 110C. The control module 120 may be configured to: sequentially or simultaneously control the first light spot shifting device 130A, the second light spot shifting device 130B, and the third light spot shifting device 130C according to the pixel positions of each sub-frame, so that at the moment corresponding to the sub-frame, the positions of the light spots of the plurality of first light sources 111A, second light sources 111B, and third light sources 111C correspond one-to-one to the positions of the pixels included in the sub-frame.
[0074] Each sub-frame of the target image can be decomposed into a first sub-frame component with a first color component, a second sub-frame component with a second color component, and a third sub-frame component with a third color component. The control module 120 can also be configured to:
[0075] Independently control the brightness of each of the multiple first light sources 111A according to the gray-scale distribution of the first sub-frame component, so that at the moment corresponding to this sub-frame, each light spot of the multiple first light sources 111A forms a gray-scale display of the first sub-frame component; that is, at the moment corresponding to this sub-frame, the brightness of each light spot of the first light sources 111A corresponds one-to-one with the gray-scale value of the first color component of each pixel of this sub-frame.
[0076] Independently control the brightness of each of the multiple second light sources 111B according to the gray-scale distribution of the second sub-frame component, so that at the moment corresponding to this sub-frame, each light spot of the multiple second light sources 111B forms a gray-scale display of the second sub-frame component; that is, at the moment corresponding to this sub-frame, the brightness of each light spot of the second light sources 111B corresponds one-to-one with the gray-scale value of the second color component of each pixel of this sub-frame.
[0077] Independently control the brightness of each of the multiple third light sources 111C according to the gray-scale distribution of the third sub-frame component, so that at the moment corresponding to this sub-frame, each light spot of the multiple third light sources 111C forms a gray-scale display of the third sub-frame component. That is, at the moment corresponding to this sub-frame, the brightness of each light spot of the third light sources 111C corresponds one-to-one with the gray-scale value of the third color component of each pixel of this sub-frame.
[0078] Regarding how to adjust the brightness of the light source corresponding to the color to correspond to the gray-scale value of the color component of the sub-frame pixel, the method is the same as that described above for adjusting the brightness of the light source to correspond to the gray-scale value of the sub-frame pixel, and will not be elaborated here.
[0079] It can be understood that Figure 5 The control module 120 in the embodiment may further include a processor 121, a light source driver 122, and a light spot shift control unit 123 as shown in Figure 4 and may also include a synchronization unit 124, which will not be elaborated here.
[0080] According to the above light source device of each embodiment of the present application, the modulation bandwidth of the light source device can be reduced, the control bandwidth of the light spot shift device can be effectively reduced, the image uniformity can be effectively improved, and when the light source is a laser, the moving light spot scheme can also effectively weaken the speckle of the formed image. In addition, in some embodiments, for a single pixel in the image, the gray-scale display of the pixel can be achieved by adjusting the brightness of the light source corresponding to the pixel, so that the two-dimensional gray-scale distribution of each sub-frame can be achieved by adjusting the brightness of each light source at the corresponding time of each sub-frame.
[0081] According to another aspect of the embodiments of the present application, an imaging method is further provided. The imaging method can be implemented by a light source device. The light source device can decompose a target image into a plurality of sub-frames with sparse sampling and includes a plurality of light sources. Each light spot emitted by the plurality of light sources corresponds one-to-one to each pixel of a sub-frame. The light source device generates a corresponding light spot array for each sub-frame in sequence within one frame time by moving the light spots, so as to obtain the image light of the target image. The light source device can be, for example, any embodiment of the light source device 100 described above. Figure 6 The flowchart of an imaging method according to an embodiment of the present application is shown. As Figure 6 shown, the exemplary imaging method includes the steps:
[0082] S610: Decompose a frame of target image to obtain a plurality of sub-frames.
[0083] At least one pixel of other sub-frames is interposed between at least two adjacent pixels of each sub-frame.
[0084] For example, after receiving the target image, the control module of the light source device (such as Figure 1 , Figure 4 , Figure 5 the control module 120 therein) decomposes the target image frame. For example, the control module can decompose the target image according to the number of pixels of the target image, the configuration parameters of the light source device, etc. For example, if the plurality of light sources included in the light source array module of the light source device is an M×N array and the target image includes X×Y pixels, the target image can be decomposed into a×b sub-frames, where X = M*a and Y = N*b, so that the number of pixels of the sub-frame is equal to the number of light sources of the light source array module, and each pixel of the sub-frame corresponds to a light source.
[0085] The specific decomposition method and details can refer to those in the respective embodiments of the light source device described above, and will not be elaborated here.
[0086] The target image including a plurality of pixels is decomposed into a plurality of sub-frames with sparse sampling. At least one pixel of other sub-frames is interposed between at least two adjacent pixels of each sub-frame. The light source device generates corresponding light spots in step S620 according to the information of these plurality of sub-frames.
[0087] S620: According to the pixel positions of each sub-frame, move the positions of the light spots emitted by the light source array module in sequence through the light spot shifting device, so that the positions of the light spots correspond to each sub-frame in sequence.
[0088] In step S620, the light source device sequentially generates corresponding light spots for each sub-frame according to the pixel positions of the multiple decomposed sub-frames. Generating corresponding light spots for a sub-frame may mean that at the moment of this sub-frame, by moving the positions of the light spots, the positions of the light spots correspond one by one to the positions of the pixels of this sub-frame.
[0089] Among them, the light source array module includes multiple light sources. The light beam emitted by each light source among the multiple light sources forms a light spot corresponding to one pixel of the target image. At the moment corresponding to the sub-frame, the positions of the multiple light spots formed by the multiple light sources correspond one by one to the positions of the multiple pixels included in this sub-frame. Each sub-frame is generated by sparsely sampling the target image. Correspondingly, the light sources included in the light source array module are also a sparse dot matrix relative to the pixel distribution of the target image.
[0090] In one example, step S620 can be implemented by the light source device through the following processing:
[0091] S621: According to the pixel positions of each sub-frame, generate a shift control signal for each sub-frame to control the light spot shifting device to move the light spot to reach the position corresponding to this sub-frame;
[0092] S622: The light spot shifting device moves the position of the light spot according to the shift control signal of each sub-frame.
[0093] Step S621 can be implemented, for example, by the control module of the light source device or the light spot shift control unit of the control module in the foregoing embodiments of the light source device. For example, the target position to which the light spot is to be moved can be determined according to the positions of the pixels of each sub-frame. Further, the moving distance, moving direction, and moving route of the light spot can be determined according to the target position and the current position of the light spot, etc. Then, the corresponding shift control signal is generated for each sub-frame according to the determined information. Further, the moving distance, moving direction, or moving route, moving speed, etc. of the light source or the light source array module of the light source device can be determined according to the distance and moving direction that the light spot needs to move, or the angle and direction by which the light beam emitted by the light source needs to be deflected, etc., and this information is included in the shift control signal.
[0094] In step S622, the light spot shifting device of the light source device moves the light spot according to the shift control signal so that the positions of the light spots correspond one by one to the positions of the pixels of the corresponding sub-frame. The light spot shifting device can move the position of the light spot by moving the positions of the multiple light sources, or can move the position of the light spot formed by the light beam by deflecting the direction of the light beam emitted by the multiple light sources.
[0095] Regarding how to sequentially generate corresponding light spots for each sub-frame according to the pixel positions of each sub-frame through light spot shifting, reference can be made to the descriptions in the foregoing embodiments of the light source device.
[0096] In one example, generating corresponding light spots for a sub-frame may further include: at the time of the sub-frame, when the light spots are shifted to positions corresponding to the sub-frame, adjusting the brightness of each light spot to be consistent with the gray levels of the pixels of the sub-frame. That is, the exemplary imaging method may further include the steps of: controlling the brightness of each of the multiple light sources according to the gray-scale distribution of each sub-frame, so that at the time corresponding to the sub-frame, each light spot of the multiple light sources forms a gray-scale display of the corresponding pixel of the sub-frame. This step may be implemented through the following processing:
[0097] Determining the brightness of each light source in the light source array module at the time of the sub-frame according to the gray-scale distribution of each sub-frame;
[0098] Generating a drive signal for each light source to drive the light source to emit light of the determined brightness according to the determined brightness of each light source;
[0099] At the time of each sub-frame, the multiple light sources emit light under the drive of the corresponding drive signals to form light spots corresponding to the sub-frame.
[0100] The above light source can be any light-emitting device, such as a vertical-cavity surface-emitting laser, an edge-emitting laser, an LED, or a Micro LED, etc. In one example, each of the multiple light sources is a pulse-driven laser light source, and the laser light source is configured to emit light when the light spot shifting device shifts the light spot to the target position. For example, the timing of the pulse driving the laser light source and the movement of the light spot shifting device can be controlled so that the laser light source emits equally spaced light spots as the light spot shifting device moves.
[0101] In one embodiment, in order to obtain an accurate consistency between the light spot position and the light spot brightness, the light spot shifting and the light source light emission can be synchronized. For example, the above exemplary imaging method may further include the steps of: controlling the light source driver and the light spot shifting device to be synchronized according to multiple sub-frames, so that when the light spot shifting device moves the light spots of the multiple light sources to positions corresponding to each of the multiple sub-frames, the light source driver drives the light source array module to emit light corresponding to the gray-scale distribution of the sub-frame. Through the synchronization step, the position movement and the brightness change of the light spots are kept consistent, so that light spots with accurate brightness can be provided at accurate pixel positions.
[0102] After forming the light spots corresponding to each sub-frame, the exemplary imaging method enters step S630.
[0103] S630: Imaging the light spots corresponding to multiple sub-frames emitted by the light source array module to obtain image light.
[0104] In step S630, the imaging module may image the light spot to obtain image light. The imaging module may be a module in the light source device or a module located outside the light source device.
[0105] In the above embodiment, the light emitted by each light source may be monochromatic light or white light. In the following embodiments, the light source emits monochromatic light of different colors. In this embodiment, the light source array module of the light source device includes a first light source array module, a second light source array module, and a third light source array module. The first light source array module includes a plurality of first light sources that emit light having a first color, the second light source array module includes a plurality of second light sources that emit light having a second color, and the third light source array module includes a plurality of third light sources that emit light having a third color.
[0106] The light spot shifting device includes a first light spot shifting device for shifting the light spot of the first light source array module, a second light spot shifting device for shifting the light spot of the second light source array module, and a third light spot shifting device for shifting the light spot of the third light source array module.
[0107] In this case, step S620 may include: sequentially or simultaneously controlling the first light spot shifting device, the second light spot shifting device, and the third light spot shifting device according to the pixel positions of each sub-frame, so that at the moment corresponding to the sub-frame, the positions of the light spots of the plurality of first light sources, second light sources, and third light sources correspond one-to-one to the positions of the pixels included in the sub-frame.
[0108] In this embodiment, each sub-frame of the target image can be decomposed into a first sub-frame component having a first color component, a second sub-frame component having a second color component, and a third sub-frame component having a third color component. Controlling the brightness of each light source among the plurality of light sources according to the gray scale distribution of each sub-frame includes:
[0109] Controlling the brightness of each of the plurality of first light sources according to the gray scale distribution of the first sub-frame component, so that at the moment corresponding to the sub-frame, each light spot of the plurality of first light sources forms a gray scale display of the first sub-frame component; that is, at the moment corresponding to the sub-frame, the brightness of each light spot corresponds one-to-one to the gray scale value of the first color component of each pixel of the sub-frame.
[0110] Controlling the brightness of each of the plurality of second light sources according to the gray scale distribution of the second sub-frame component, so that at the moment corresponding to the sub-frame, each light spot of the plurality of second light sources forms a gray scale display of the second sub-frame component; that is, at the moment corresponding to the sub-frame, the brightness of each light spot corresponds one-to-one to the gray scale value of the second color component of each pixel of the sub-frame.
[0111] Control the brightness of each of the multiple third light sources according to the gray-scale distribution of the third sub-frame component, so that at the moment corresponding to this sub-frame, each light spot of the multiple third light sources forms a gray-scale display of the third sub-frame component. That is, at the moment corresponding to this sub-frame, the brightness of each light spot corresponds one-to-one with the gray-scale value of the third color component of each pixel of this sub-frame.
[0112] Regarding how to adjust the brightness of the light source corresponding to the color to correspond to the gray-scale value of the color component of the sub-frame pixel, the method is the same as that described above for adjusting the brightness of the light source to be consistent with the gray-scale value of the sub-frame pixel, and will not be elaborated here.
[0113] In the case where the light source array module emits multiple monochromatic lights as described above, before the imaging step S630, the exemplary imaging method further includes the step of combining the light spots of the multiple first light sources, second light sources, and third light sources. In this step, for a light source group composed of a first light source, a second light source, and a third light source with corresponding positions, a light combining module can be used to combine the three light spots emitted by this group of light sources into one light spot. In this way, the three monochromatic light spot arrays emitted by the three light source array modules are finally combined by the light combining module into a mixed-color light spot array, such as a white light spot array. Then in step S630, the combined light spots are imaged to obtain image light.
[0114] For the specific details of the above steps or processes, reference can be made to the respective embodiments of the light source device described above, and will not be elaborated here. Conversely, the descriptions in the respective embodiments of the imaging method can also be used as a reference for the respective embodiments of the aforementioned light source device.
[0115] According to the imaging method of the embodiments of the present application, the target image in the source image signal can be decomposed into multiple sub-frames with sparse sampling (that is, at least one pixel of other sub-frames is interposed between at least two adjacent pixels of each sub-frame). The pixels of each sub-frame correspond one by one to the light sources of the light source array module, and light spots corresponding to each sub-frame are sequentially formed according to the time sequence. Among them, when switching from one sub-frame to the next sub-frame, the position of the light spot is moved by the light spot shifting device so that it corresponds to the pixel position of the corresponding sub-frame. During the time of displaying one frame of image, the light spots corresponding to each light source are moved to correspond to multiple image pixel points. Since the overall resolution is achieved by the light source array including multiple light sources, and each light source can be modulated separately to contribute to the overall resolution, compared with a single light source contributing to the overall resolution, the embodiments of the present application reduce the modulation bandwidth of the light source device. In addition, since the light spot corresponding to a single light source only needs to cover a certain area in the overall image, the embodiments of the present application can effectively reduce the control bandwidth of the light spot shifting device. In addition, since a certain area in the overall image is formed by moving a single light source, the embodiments of the present application can effectively improve the image uniformity. In addition, the embodiments of the present application use a light source array as the light source. When the light source is a laser, the moving light spot scheme can also effectively reduce the speckle of the formed image.
[0116] As described above, in some embodiments of the imaging method of the present application, the two-dimensional gray-scale distribution of each sub-frame is realized by adjusting the brightness of each light source during its corresponding time period, avoiding the use of the currently less efficient spatial light modulator. Therefore, the efficiency of the imaging method can be greatly improved. In addition, since the brightness of a single pixel can be fully turned on / fully turned off by adjusting the brightness of the light source, these embodiments can achieve high contrast and high dynamic range.
[0117] In addition, in some embodiments of the imaging method, each light source of the light source array module is independently addressable, that is, independently controllable. Therefore, variable optical coding can be realized, thereby improving the imaging accuracy. In addition, when each light source is independently controllable, the gray level of a single pixel can be realized by modulating the light intensity of the corresponding single light source, and the adjustment method is simple and easy. In addition, since the brightness of a single pixel can be fully turned on / fully turned off by adjusting the brightness of the light source, these embodiments can achieve high contrast and high dynamic range. The dot matrix or structured light generated by this scheme can be quickly transformed to generate customized patterns at an extremely high speed.
[0118] The above embodiments of the exemplary light source device and the exemplary imaging method can be applied to many occasions. For example, they can be used for projection image display or 3D imaging of objects.
[0119] In a projection image display application, the image light obtained in step S630 can be projected onto a screen so that the target image is reproduced on the screen. In such an application scenario, the embodiments of the above light source device can be integrated into a display device, and the display device may further include an imaging module for imaging the light spot emitted by the light source device to obtain image light and projecting the image light onto the screen.
[0120] In an object 3D imaging application, the image light obtained in S630 can be used as structured light, and the exemplary imaging method may then include the steps of:
[0121] Irradiating the image light onto the object to be measured; collecting the image light modulated by the object to be measured; processing the collected modulated image light to obtain the three-dimensional information of the object to be measured.
[0122] In such an application scenario, the embodiments of the above light source device can be integrated into an imaging device for 3D imaging of the object to be measured, and the imaging device may further include:
[0123] An imaging module for forming image light based on the light spot output by the light source device and irradiating it onto the object to be measured.
[0124] A collection module for collecting the image light modulated by the object to be measured.
[0125] An image processing module for processing the modulated image light collected by the collection module to obtain the three-dimensional information of the object to be measured.
[0126] Hereinafter, exemplary embodiments of the imaging device and the display device will be described in detail respectively.
[0127] In addition to being able to achieve 2D imaging of a target object, 3D imaging technology can also obtain information about the target in the depth dimension, so 3D stereoscopic scanning or modeling can be achieved. Common 3D imaging schemes may include those based on diffractive optical elements (DOEs), 3D structured light scanning schemes, vertical cavity surface emitting laser (VCSEL) light source array systems based on micro-electromechanical systems (MEMS), and 3D structured light based on digital light processing (DLP), etc.
[0128] However, the regulation of the projected structured light is mainly achieved through multiple closely arranged light source arrays, DOE, and some spatial processing. The light sources do not achieve independent addressing control, the number of images that can be regulated is limited, dynamic modulation of images cannot be performed, and the achievable accuracy and resolution are limited. When implementing a DLP-based 3D structured light solution using a digital micromirror device (DMD), the efficiency of the DMD spatial light modulator is low, and the required heat dissipation module is large. Therefore, the entire system is complex, large in volume, and low in efficiency.
[0129] Currently, more commonly used are regular and irregular light source arrays, or multiple light source arrays are used to project spots with different sparsity degrees and different arrangements. The light beams are received and collimated by a lens unit (such as a microlens array or a lens group), then projected into space, and then one or more DOE are used to copy and magnify the light beams emitted by the light source array by different multiples, as Figure 7 shown in the 3D imaging scheme based on the light source array to achieve structured light for different application scenarios; or one or more combinations of translation, rotation, mirroring, or scaling can be performed on multiple light source arrays to obtain a laser speckle image with a uniform overall particle distribution but a high degree of local irrelevance, so as to obtain higher accuracy.
[0130] The VCSEL light source array system based on MEMS reflects the array light beams emitted by regular or irregular VCSELs through the vibration of the MEMS micromirror and projects them onto the object in the form of a dot matrix. The aim is to copy the VCSEL dot matrix through the fast scanning of MEMS to achieve a denser spot distribution and improve accuracy, as Figure 8 shown; the regulation of the projected structured light is mainly achieved through multiple closely arranged light source arrays, DOE, and some spatial processing. The light sources do not achieve independent addressing control, the number of images that can be regulated is limited, dynamic modulation of images cannot be performed, and the achievable accuracy and resolution are limited.
[0131] For a DLP-based 3D structured light solution, when designers need to perform fast high-precision scanning with a resolution from millimeters to micrometers, a DLP-based structured light system is often selected to utilize the DMD to achieve high-speed real-time 3D scanning. However, the efficiency of the DMD spatial light modulator is low, and the required heat dissipation module is large. Therefore, the entire system is complex, large in volume, and low in efficiency.
[0132] Figure 9 The schematic structural block diagram of an imaging device according to an embodiment of the present application is shown. As Figure 9As shown, the imaging device 900 includes a light source device 100, an imaging module 920, a collection module 930, and an image processing module 940. Among them, the light source device 100 and the imaging module 920 form a test pattern generation module 910 for generating structured light. The light source device 100 can be the various light source device embodiments described above. In Figure 9 the embodiment, the control module of the light source device is divided into a decoder 911 and a light source array driving module 912, and the beam scanning / deflection actuator 913 is equivalent to the spot shifting device 130 in the above-described light source device embodiments.
[0133] The light source array module 110 in the test pattern generation module 910 uses electrodes with independent control of each light source to achieve fast single-point control of each laser light source through a driver. Since the array light sources of the light source array module 110 need to be independently addressed and regulated, the array adopts a sparse dot matrix form, arranged in an M*N dot matrix, as Figure 4 shown. Through the optical imaging lens of the imaging module 920, M*N sparse pixel points can be achieved on the screen. To display an image with densely arranged pixels in one frame, an image in one frame needs to be split into a*b sub-frames displayed in a time-division multiplexing manner, that is, the spot corresponding to each independently addressed and controlled light source is expanded into a*b densely arranged spots through time-division multiplexing, corresponding to a*b densely arranged pixels in one frame of the image, which exactly fills the gaps between several adjacent independently addressable and controllable light sources. Within the time of one frame, the switching between sub-frames can be achieved through a micro actuator. Finally, aM*bN pixel points are achieved on the screen. Since the time for switching between sub-frames is much greater than the minimum time that the human eye's visual persistence phenomenon can respond to, the integration effect of the human eye stitches multiple sub-frames into a complete image. The above description divides an image in one frame into a*b non-overlapping sub-frames, and a*b sub-frames are only repeated once in one frame. The principle of repeating a*b sub-frames multiple times is similar, and only the regulation rate of the micro actuator needs to be increased, which will not be elaborated here.
[0134] A detailed frame-splitting schematic diagram is as Figure 3 shown, corresponding to the case of a = 2 and b = 2. At time t1, the sparse dot matrix light source is at position 1, and at time t2, it is at position 2, and so on. Within the time of one frame, the light source is successively at positions 1, 2, 3, 4, and each light source forms non-overlapping 2*2 densely arranged pixels, and as a whole, 2M*2N pixels are formed.
[0135] After being converted by the decoder 911, the video signal source is transmitted to the light source array driving module 912. Different gray levels are achieved by controlling the brightness and darkness of the light source at each spot position, completing the regulation of a sub-frame image. At this time, the image acquisition module 930 acquires the image and transmits it to the image processing module 940 for analysis. In another sub-frame, the beam scanning / deflection actuator 913 moves the spot corresponding to the array light source to its corresponding position, and at the same time, the light source array driving module 912 drives the array light source according to the gray level corresponding to this sub-frame, so that the gray level distribution of the corresponding sub-frame is displayed on the image. The image acquisition module 930 acquires the image and transmits it to the image processing module 940 for analysis again. Finally, the image processing module 940 analyzes and compares all the displayed images to achieve high-precision 3D imaging.
[0136] Figure 10 FIG. shows a schematic structural diagram of an imaging device 1000 according to another embodiment of the present application, in which a VCSEL that can be independently addressed and regulated is used as the array light source of the light source array module, and a micro actuator 1010 is used as a spot shifting device to vibrate the light source array module 110 to achieve spot shifting. Among them, the decoder 1021, the VCSEL driver 1022, the micro actuator driver 1023, and the synchronization device 1024 respectively correspond to the processor 121, the light source driver 122, the spot shifting controller 123, and the synchronization unit 124 that make up the control module 120 as described above.
[0137] After being decoded and processed by the decoder 1021, the video source is transmitted to the VCSEL driver 1022 and the micro actuator driver 1023, and the synchronization device 1024 ensures their synchronization. The VCSEL light source of the light source array module 110 is installed on the micro actuator 1010. The micro actuator 1010 can be a two-dimensional micro actuator, or it can be two one-dimensional micro actuators. The two one-dimensional micro actuators respectively control two mutually perpendicular directions, so that the VCSEL has vibrations in two directions. These two vibration directions can be one with a fast frequency and one with a slow frequency. Among them, the slow frequency direction vibrates in a step-by-step manner. The micro actuator 1010 can be a linear motion actuator or a rotary actuator. The laser light source VCSEL is driven by a pulse so that it emits light when the micro actuator 1010 moves to the required spot position. For example, the diameter of a single VCSEL light source is 15 microns, the spacing between each light source in the x and y directions is 150 microns, there are 200 light sources in the x direction, and 100 light sources in the y direction. The entire VCSEL light source array is about 30 mm long and about 15 mm wide. Then when the vibration frequency in the x direction is 600 Hz and the vibration frequency in the y direction is 60 Hz, a resolution of 2k and a refresh rate of 60 Hz can be achieved. Among them, in the case of two one-dimensional micro actuators, the one-dimensional micro actuator in the x direction can be a high-frequency piezoelectric ceramic actuator, and the one-dimensional micro actuator in the y direction can be, but is not limited to, a piezoelectric moving platform, a piezoelectric stepping motor, or a one-dimensional deflection stage. In the case of a two-dimensional micro actuator, the two-dimensional micro actuator can use a high-frequency two-dimensional deflection stage to achieve deflection in two directions at the same time. The pulse timing of the laser light source can be controlled to match the displacement curve of the micro actuator 1010, so that the VCSEL projects equally spaced spots. For example, when the movement curve is a sine wave, by modulating the pulse timing, an equal-spacing output can be achieved, as Figure 11 shown. When reaching a sub-frame, the micro actuator 1010 moves the spots corresponding to the array light sources to their corresponding positions, and at the same time, the VCSEL driver 1022 drives the array light sources according to the gray level corresponding to this sub-frame, so that the gray level distribution of the corresponding sub-frame is displayed on the image. The obtained closely packed pixel points are optically magnified by the imaging module 920 and finally projected onto the object to be measured. The acquisition module 930 acquires the light modulated by the object and transmits the signal to the image processing module 940. The image processing module 940 calculates the signal and then obtains the three-dimensional information of the object to be measured.
[0138] In this implementation scheme, the vibration bandwidth of the micro actuators in two dimensions is reduced by the sparse dot matrix light source. The system is simple, small in size, high in resolution, and can modulate the image without an additional spatial light modulator, achieving high-precision 3D imaging.
[0139] Figure 12FIG. 0 shows a schematic structural diagram of an imaging device 1200 according to another embodiment of the present application. Here, Micro LEDs are used as the sparse array light source of the light source array module, and a MEMS scanning mirror or a phase deflection device is used to achieve beam scanning / spot shifting. Among them, the decoder 1221, the LED driver 1222, the scanning device driver 1223, and the synchronization device 1224 respectively correspond to the processor 121, the light source driver 122, the spot shifting controller 123, and the synchronization unit 124 of the composition control module 120 as described above.
[0140] As Figure 12 shown, after the video source passes through the decoder 1221, the signal is transmitted to the LED driver 1222 and the scanning device driver 1223, and the synchronization device 1224 ensures the synchronization of the two. The function of the phase deflector / MEMS mirror 1230 as the spot shifting device is to achieve beam deflection. The phase deflector uses the principle of light diffraction and realizes the deflection of the main optical level by modulating the phase of light. Typical devices are such as acousto-optic deflectors and liquid crystals. The MEMS uses piezoelectric ceramics as the driving source, can achieve two-dimensional rapid flipping, and realizes beam deflection by using the principle of light reflection.
[0141] For example, the diameter of a single Micro LED light source in the LED light source array 1210 is 15 microns, the pitch of each light source in the x and y directions is 150 microns, there are 200 light sources in the x direction, and 100 light sources in the y direction. The entire Micro LED light source array is about 30 mm long and about 15 mm wide. Then when the scanning frequency in the x direction is 600 Hz and the scanning frequency in the y direction is 60 Hz, a resolution of 2k and a refresh rate of 60 Hz can be achieved. When using an acousto-optic deflector as the beam deflection device, since the response time of the acousto-optic deflector is in the ns level, it is not necessary to pulse drive the light source to achieve a densely arranged pixel point layout. When reaching a sub-frame, the phase deflector / MEMS mirror 1230 moves the spot of the LED light source array 1210 to the position corresponding to this sub-frame under the drive of the scanning device driver 1223. At the same time, the LED driver 1222 drives the LED light source array 1210 according to the gray level corresponding to this sub-frame, so that the gray level distribution of the corresponding sub-frame is displayed on the image. The obtained densely arranged pixel points are optically magnified by the imaging module 920 and finally projected onto the object to be measured. The acquisition module 930 acquires the light modulated by the object and transmits the signal to the image processing module 940. The image processing module 940 calculates the signal and then obtains the three-dimensional information of the object.
[0142] This implementation uses a sparse dot matrix light source, with a simple system, small volume, high resolution, and can achieve image modulation without an additional spatial light modulator, realizing high-precision 3D imaging.
[0143] Figure 13 shows a schematic structural diagram of a display device according to an embodiment of the present application. As Figure 13 shown, the exemplary display device 1300 includes a light source array module 1310, a decoder 1321, a beam scanning / deflection actuator 1330, a light source array driver 1322, a light combining module 1340, and an imaging module 1350. Among them, the decoder 1321 and the light source array driver 1322 constitute the control module 120 in the embodiments of the light source device as described above. The beam scanning / deflection actuator 1330 is equivalent to the spot shifting device 130 in the embodiments of the light source device as described above. The light source array module 1310, the decoder 1321, the beam scanning / deflection actuator 1330, and the light source array driver 1322 constitute a light source device module equivalent to the light source device modules in the embodiments of the light source device as described above.
[0144] As Figure 13 shown, the array light sources of the light source array module 1310 use electrodes with independent control for each light source, and fast single-point control of each laser light source is achieved through the light source array driver 1322. Since the array light sources need to be independently addressed and regulated, the array light sources of the light source array module 1310 are in the form of a sparse dot matrix, arranged in a dot matrix of M*N, as Figure 4 shown. Through the optical imaging lens of the imaging module 1350, M*N sparse pixel points can be realized on the screen. To display an image with densely arranged pixels in one frame, one frame of the image needs to be split into a*b sub-frames displayed by time-division multiplexing, that is, the spot corresponding to each independently addressable and controllable light source is expanded into a*b densely arranged spots by time-division multiplexing, corresponding to a*b densely arranged pixels in one frame of the image, which exactly fills the gaps between several adjacent independently addressable and controllable light sources. Within the time of one frame, the switching between sub-frames can be realized through the beam scanning / deflection actuator 1330, and finally aM*bN pixel points are realized on the screen. Since the time for switching between sub-frames is much greater than the minimum time that the human eye's visual persistence phenomenon can respond to, the integration effect of the human eye stitches multiple sub-frames into a complete image. The above description divides one frame of the image into a*b non-overlapping sub-frames, and one frame only repeats a*b sub-frames once. The principle of repeating a*b sub-frames multiple times is similar, and only the regulation rate of the micro actuator needs to be increased, which will not be elaborated here. It should be noted that the a*b spots corresponding to the same independently controllable light source may not be densely arranged, but may have overlap or gaps in the middle, and the specific scheme can be determined according to the actual imaging requirements.
[0145] A detailed frame-splitting schematic diagram is as Figure 3As shown, it corresponds to the case where a = 2 and b = 2. At time t1, the sparse dot-matrix light source is at position 1, at time t2 it is at position 2, and so on. Within the time of one frame, the light source is successively at positions 1, 2, 3, 4. Each light source forms a non-overlapping 2*2 closely-packed pixel, and overall forms 2M*2N pixels. Figure 17 shows the Figure 2 schematic diagram of frame splitting for an example image corresponding to the frame splitting method shown.
[0146] After the video signal source is converted by the decoder 1321, it is passed to the light source array driver 1322. Different gray levels are achieved by controlling the brightness and darkness of the light source at each spot position, completing the regulation of a sub-frame image. When it comes to another sub-frame, the beam scanning / deflection actuator 1330 moves the spots corresponding to the array light source to the positions corresponding to this sub-frame. At the same time, the light source array driver 1322 drives the array light source according to the gray scale corresponding to this sub-frame, so that the gray scale distribution of the corresponding sub-frame is displayed on the image. In this embodiment, the light source array module 1310 includes three light sources that respectively emit three different colors of light (such as light of three colors G, R, and B). By using the light combining module 1340 to combine the light of three colors such as G, R, and B, and passing through the imaging module 1350, a color image is realized on the screen.
[0147] Figure 14 shows a schematic structural diagram of a display device 1400 according to another embodiment of the present application. Among them, a VCSEL that can be independently addressed and regulated is used as the array light source of the light source array module, and a micro actuator is used as the spot shifting device to vibrate the light source. Among them, the decoder 1421, the VCSEL driver 1422, the micro actuator driver 1423, and the synchronization device 1424 respectively correspond to the processor 121, the light source driver 122, the spot shifting controller 123, and the synchronization unit 124 that make up the control module 120 as described above.
[0148] In Figure 14 the embodiment, the light source array module includes a first light source array module 1410A that emits B (blue) light, a second light source array module 1410B that emits R (red) light, and a third light source array module 1410C that emits G (green) light, and they are respectively located at different positions. The three light source array modules have an equal number of light sources. Three spots with three colors emitted by each light source of the first light source array module 1410A, a corresponding light source in the second light source array module 1410B, and a corresponding light source in the third light source array module 1410C can be combined into a white light spot by the light combining module 1440. In this way, three monochromatic spot arrays emitted by the three light source array modules are finally combined by the light combining module 1440 into a mixed-color spot array, such as a white light spot array.
[0149] In Figure 14 the illustrated embodiment, the micro actuators serving as the spot shift devices may correspondingly include a first micro actuator 1430A for moving the spot of the first light source array module 1410A, a second micro actuator 1430B for moving the spot of the second light source array module 1410B, and a third micro actuator 1430C for moving the spot of the third light source array module 1410C.
[0150] After being decoded by the decoder 1421, the video source is transmitted to the VCSEL driver 1422 and the micro actuator driver 1423, and the synchronization device 1424 is used to ensure the synchronization between the two. The VCSELs of each light source array module 1410A, light source array module 1410B or light source array module 1410C are mounted on a two-dimensional micro actuator or two one-dimensional micro actuators. The two one-dimensional micro actuators respectively control two mutually perpendicular directions, so that the VCSEL has vibrations in two directions. The overall scheme is as Figure 14 shown. The vibrations in these two dimensions can be one with a fast frequency and the other with a slow frequency. The slow frequency direction vibrates in a step-by-step manner. The micro actuator can be a linear motion actuator or a deflection actuator. The laser light source can be driven by pulses to emit light when the micro actuator moves to the required spot position. For example, the diameter of a single VCSEL light source is 15 microns, the pitch of each light source in the x and y directions is 150 microns, there are 200 light sources in the x direction, and 100 light sources in the y direction. The entire VCSEL light source array is about 30 mm long and about 15 mm wide. Then, when the vibration frequency in the x direction is 600 Hz and the vibration frequency in the y direction is 60 Hz, a resolution of 2k and a refresh rate of 60 Hz can be achieved. Among them, the micro actuator in the x direction can be a high-frequency piezoelectric ceramic actuator, and the micro actuator in the y direction can be a piezoelectric moving platform, a piezoelectric stepping motor or a one-dimensional deflection stage. In the case of a two-dimensional micro actuator, a high-frequency two-dimensional deflection stage can be selected to achieve deflections in both directions simultaneously. The pulse timing of the laser light source can be controlled to match the displacement curve of the micro actuator, so as to project equally spaced spots. For example, when the movement curve is a sine wave, by modulating the pulse timing, an equally spaced output can be achieved, as Figure 11As shown. At each next sub-frame, the micro actuator moves the light spot corresponding to the array light source to the position corresponding to the sub-frame. At the same time, the VCSEL driver 1422 drives the array light sources of each light source array module according to the gray scale corresponding to the sub-frame. Its response time is at the ns level, which can make the gray scale distribution of the corresponding sub-frame displayed on the image. In one example, the VCSEL driver 1422 drives the light source array modules emitting corresponding color light respectively according to the gray scales corresponding to different color components of the sub-frame. The light spots of different colors emitted by the three light source array modules correspond to the gray scales of different color components of the sub-frame. For each color component, the sparse array light spots of multiple sub-frames obtain densely arranged pixel points through time division multiplexing within one frame time.
[0151] The obtained densely arranged pixel points are subjected to RGB three-color light combination by the light combination module 1440, and then optically amplified by the imaging module 1450, and finally projected onto the screen to achieve color imaging. The RGB three-color light sources need to achieve pixel-level alignment and require synchronization in time movement.
[0152] This implementation scheme reduces the vibration bandwidth of the micro actuators in two dimensions through the sparse dot matrix light source, realizes gray scale through direct driving of the light source, does not require an additional spatial light modulator, has a simple system, small volume, high efficiency, high resolution, and can simultaneously achieve high dynamic contrast. Due to the large number of light sources used, the speckle effect of the laser can be effectively reduced.
[0153] Figure 15 The schematic structural diagram of a display device according to another embodiment of the present application is shown. Among them, three-color Micro LEDs are used as the sparse array light source of the light source array module, and a MEMS scanning mirror or a phase deflection device is used as the light spot shifting device to realize beam scanning / light spot shifting. Among them, the decoder 1521, the LED driver 1522, the scanning device driver 1523, and the synchronization device 1524 respectively correspond to the processor 121, the light source driver 122, the light spot shifting controller 123, and the synchronization unit 124 that make up the control module 120 as before.
[0154] After being decoded by the decoder 1521, the video source is transmitted to the LED driver 1522 and the scanning device driver 1523, and the synchronization device 1524 ensures the synchronization of the two. The overall scheme is as Figure 15 shown. The function of the phase deflector / MEMS mirror 1530 as the light spot shifting device is to realize beam deflection, so as to realize light spot shifting. The phase deflector uses the diffraction principle of light and realizes the deflection of the main light level by modulating the phase of light. Typical devices are such as acousto-optic deflectors and liquid crystals. The MEMS uses piezoelectric ceramics as the driving source, can realize two-dimensional rapid flipping, and realizes beam deflection using the reflection principle of light.
[0155] The diameter of a single Micro LED light source is approximately 15 micrometers. In this embodiment, each light source of the LED light source array 1510 is a combined light source formed by placing three Micro LED light sources that respectively emit R, G, and B lights together. Figure 16 A schematic diagram of a Micro LED combined light source according to an embodiment of the present application is shown. Three Micro LED light sources that respectively emit R, G, and B lights are placed close together and arranged in a triangular pattern. The diameter of this combined light source is approximately 40 micrometers.
[0156] Assume that the pitch of each combined light source in the x and y directions is 400 micrometers, there are 200 light sources in the x direction, and 100 light sources in the y direction. The entire Micro LED light source array is approximately 80 mm long and 40 mm wide. Then when the scanning frequency in the x direction is 600 Hz and the scanning frequency in the y direction is 60 Hz, a resolution of 2k and a refresh rate of 60 Hz can be achieved. When using an acousto-optic deflector as the beam deflector device, since the response time of the acousto-optic deflector is at the ns level, it is not necessary to pulse-drive the light source to achieve a densely arranged pixel point layout. The response time of the LED driver 1522 is at the ns level. By driving the array light sources according to the gray levels corresponding to the sub-frames, the gray level distribution of the corresponding sub-frames is displayed on the image. The obtained densely arranged pixel points are optically magnified by the imaging module 1540 and finally projected onto the screen to obtain a color image.
[0157] This implementation scheme reduces the control bandwidth of the light source and the vibration frequency of the micro actuator through a sparse dot matrix light source, realizes gray levels through direct driving of the light source, and does not require an additional spatial light modulator. Since three light sources of GRB are combined into a combined light source, there is no need for a light combining device, nor is it necessary to consider the synchronization accuracy of the three-color light sources. The system is simple, small in size, high in efficiency, high in resolution, and can simultaneously achieve a high dynamic contrast ratio.
[0158] The above are only embodiments of the present application, and do not limit the patent scope of the present application accordingly. Any equivalent structural or equivalent process transformation made by using the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall be similarly included in the patent protection scope of the present application.
Claims
1. A light source device, characterized in that, It includes a light source array module, a control module, and a spot shifting device, where: The light source array module includes a plurality of light sources arranged in an array. Each light source among the plurality of light sources emits a light beam to form a spot corresponding to a pixel of a frame of target image. The target image includes a plurality of pixels and is composed of a plurality of sub - frames. Each sub - frame among the plurality of sub - frames contains a part of the plurality of pixels, and the pixels contained in the plurality of sub - frames together form the plurality of pixels; The spot shifting device is configured to move the positions of the spots of the plurality of light sources under the control of the control module; The control module is configured to control the spot shifting device in sequence according to the timing so that the positions of the spots of the plurality of light sources correspond to each sub - frame in turn. The control module is configured to: control the spot shifting device according to the pixel positions of each sub - frame so that at the moment corresponding to this sub - frame, the positions of the spots of the plurality of light sources correspond one - to - one with the positions of the pixels contained in this sub - frame. At least one pixel of other sub - frames is interposed between at least two adjacent pixels of each sub - frame.
2. The light source device according to claim 1, characterized in that, The density of the array formed by the plurality of light sources is less than the density of the pixel distribution of the target image.
3. The light source device according to claim 1 or 2, characterized in that, The control module is further configured to control the brightness of each light source among the plurality of light sources according to the gray - scale distribution of each sub - frame so that at the moment corresponding to this sub - frame, each spot of the plurality of light sources forms the gray - scale display of the corresponding pixel of this sub - frame.
4. The light source device according to claim 3, characterized in that, Each light source among the plurality of light sources is independently controlled, and the control module is configured to independently control the brightness of each light source among the plurality of light sources according to the gray - scale distribution of each sub - frame.
5. The light source device according to claim 1, characterized in that, The plurality of light sources of the light source array module is an M×N array, the target image contains X×Y pixels, and the number of sub - frames contained in the target image is a×b, where X = M*a and Y = N*b.
6. The light source device according to claim 1, characterized in that, The plurality of sub - frames includes a first sub - frame. Between every two adjacent pixels of the first sub - frame, one or more pixels of one or more other sub - frames are interposed.
7. The light source device according to claim 1, characterized in that, The control module includes: a processor, a light source driver, and a spot shifting control unit, where: The processor is configured to perform image processing on the received source image signal to obtain the target image including the plurality of sub - frames; The light source driver is configured to generate a signal for driving the light source array module to emit light according to the plurality of sub - frames; and The spot shifting control unit is configured to generate a signal for controlling the spot shifting device to move the spots according to the plurality of sub - frames.
8. The light source device according to claim 7, characterized in that, The control module further includes a synchronization unit. The synchronization unit is configured to synchronize the light source driver and the spot shifting device according to the plurality of sub - frames so that when the spot shifting device moves the spots of the plurality of light sources to positions corresponding to each sub - frame among the plurality of sub - frames, the light source driver drives the light source array module to emit light corresponding to the gray - scale distribution of this sub - frame.
9. The light source device according to claim 8, characterized in that, Each of the multiple light sources is a pulse-driven laser light source, and the laser light source is configured to emit light when the spot shifting device shifts the spot to the target position. Among them, the synchronization unit is configured to control the timing of the pulses driving the laser light source and the movement of the spot shifting device, so that the laser light source emits equidistant spots as the spot shifting device moves.
10. The light source device according to claim 9, characterized in that, The spot shifting device is a beam deflection device, and the beam deflection device is a MEMS scanning mirror or a phase deflection device.
11. The light source device according to claim 1, characterized in that, The spot shifting device is a light source shifting device, and the light source shifting device is used to move the positions of the multiple light sources.
12. The light source device according to claim 11, characterized in that, The light source shifting device is a two-dimensional micro actuator moving in the first direction and the second direction perpendicular to each other, or a first one-dimensional micro actuator moving in the first direction and a second one-dimensional micro actuator moving in the second direction.
13. The light source device according to claim 12, characterized in that, The movement of the two-dimensional micro actuator in the first direction is faster than the movement in the second direction, or the movement of the first one-dimensional micro actuator is faster than the movement of the second one-dimensional micro actuator.
14. The light source device according to claim 12, characterized in that, The two-dimensional micro actuator is a two-dimensional deflection stage; the first one-dimensional micro actuator is a high-frequency piezoelectric ceramic actuator, and the second one-dimensional micro actuator is a piezoelectric moving platform, a piezoelectric stepping motor or a one-dimensional deflection stage.
15. The light source device according to claim 1, characterized in that, The spot shifting device is a beam deflection device, and the beam deflection device is used to deflect the direction of the light beams emitted by the multiple light sources to move the position of the spot formed by the light beams.
16. The light source device according to claim 1, characterized in that, Each of the multiple light sources is a pulse-driven laser light source, and the laser light source is configured to emit light when the spot shifting device shifts the spot to the target position.
17. The light source device according to claim 1, characterized in that, Each of the multiple light sources is a vertical cavity surface emitting laser, an edge emitting laser, an LED or a Micro LED.
18. The light source device according to claim 1, characterized in that, The light source array module includes a first light source array module, a second light source array module and a third light source array module. The first light source array module includes multiple first light sources emitting light with a first color, the second light source array module includes multiple second light sources emitting light with a second color, and the third light source array module includes multiple third light sources emitting light with a third color; The spot shifting device includes a first spot shifting device for moving the spot of the first light source array module, a second spot shifting device for moving the spot of the second light source array module, and a third spot shifting device for moving the spot of the third light source array module; The control module is configured to: sequentially or simultaneously control the first spot shifting device, the second spot shifting device and the third spot shifting device according to the pixel positions of each sub-frame, so that at the moment corresponding to the sub-frame, the positions of the spots of the multiple first light sources, second light sources and third light sources correspond one-to-one with the positions of the pixels included in the sub-frame.
19. The light source device according to claim 18, characterized in that, Each sub-frame of the target image is decomposed into a first sub-frame component with a first color component, a second sub-frame component with a second color component and a third sub-frame component with a third color component. The control module is further configured to: Independently control the brightness of each of the multiple first light sources according to the gray-scale distribution of the first sub-frame component, so that at the moment corresponding to this sub-frame, each light spot of the multiple first light sources forms the gray-scale display of the first sub-frame component; Independently control the brightness of each of the multiple second light sources according to the gray-scale distribution of the second sub-frame component, so that at the moment corresponding to this sub-frame, each light spot of the multiple second light sources forms the gray-scale display of the second sub-frame component; Independently control the brightness of each of the multiple third light sources according to the gray-scale distribution of the third sub-frame component, so that at the moment corresponding to this sub-frame, each light spot of the multiple third light sources forms the gray-scale display of the third sub-frame component.
20. The light source device according to claim 19, characterized in that, The light source device further includes: A light combining module for combining the light spots of the multiple first light sources, the multiple second light sources, and the multiple third light sources.
21. An imaging device, characterized in that, Including the light source device according to any one of claims 1-20.
22. The imaging device according to claim 21, characterized in that, The imaging device further includes an imaging module, a collection module, and an image processing module, wherein: The imaging module is used to form image light based on the light spots output by the light source device and irradiate the object to be measured; The collection module is used to collect the image light modulated by the object to be measured; The image processing module is used to process the modulated image light collected by the collection module to obtain the three-dimensional information of the object to be measured.
23. A display device, characterized in that, Including the light source device according to any one of claims 1-20.
24. The display device according to claim 23, characterized in that, It further includes an imaging module for imaging the light spots emitted by the light source device to obtain image light and projecting the image light onto the screen.
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