CN113965736A

CN113965736A - Image forming method

Info

Publication number: CN113965736A
Application number: CN202010707036.9A
Authority: CN
Inventors: 胡飞; 陈晨; 陈彦哲; 李屹
Original assignee: Appotronics Corp Ltd
Current assignee: Shenzhen Appotronics Corp Ltd
Priority date: 2020-07-21
Filing date: 2020-07-21
Publication date: 2022-01-21
Also published as: WO2022017273A1

Abstract

The application discloses an imaging method, comprising: decomposing a frame of target image to obtain a plurality of subframes, wherein at least one pixel of other subframes is inserted between at least two adjacent pixels of each subframe; moving the position of the light spot emitted by the light source array module through the light spot shifting device according to the pixel position of each sub-frame and the time sequence, so that the position of the light spot sequentially corresponds to each sub-frame; the light source array module comprises a plurality of light sources, light beams emitted by each light source in the plurality of light sources form light spots corresponding to one pixel of a target image, and the positions of the light spots formed by the plurality of light sources and the positions of the pixels contained in the subframe correspond to each other one by one at the moment corresponding to the subframe.

Description

Image forming method

Technical Field

The application relates to the technical field of optical information processing, in particular to an imaging method.

Background

In technologies such as 3D imaging of objects, projection display, etc., it is generally necessary to form image light from a source image using an imaging system including a light source, a spatial light modulator, a projection lens, etc., to reproduce the source image, which is referred to herein as an imaging technology. Common imaging solutions include spatial light modulator-based imaging solutions, beam scanning-based imaging solutions, and the like.

Existing imaging schemes based on spatial light modulators generally include a scheme based on a DMD (Digital micromirror device), a scheme based on an LCD (Liquid Crystal Display), and a scheme based on an LCOS (Liquid Crystal on Silicon).

DMD-based schemes: digital Light Processing (DLP) display technology images are generated by the DMD. The DMD is a spatial light modulator in which a matrix of micromirrors (precision, micro mirrors) each controlling a pixel in a projected picture is arranged on a semiconductor chip, the number of micromirrors corresponding to the resolution of the projected picture. The light source is projected on the DMD, the micro lens can be rapidly turned over under the driving of a digital signal, on (on) and off (off) states exist, the lens only receives light in the on state, different gray levels are obtained through the control of the on and off states, and then a color image is obtained.

LCD-based solutions: the LCD liquid crystal display places the liquid crystal box in two parallel glass substrates, set up TFT (thin film transistor) on the lower base plate glass, set up the colored filter on the upper substrate glass, change and come the rotation direction of the liquid crystal molecule through signal and voltage on the TFT, thus reach the polarized light emergence state of controlling every pixel point and obtain the gray scale, realize the colored imaging. The principle is that the birefringence of liquid crystal molecules is utilized, the liquid crystal molecules can regularly rotate by 90 degrees under the action of different current electric fields through certain liquid crystal molecule arrangement (usually nematic), the difference of transmittance can be generated for incident polarized light, the on-state and off-state conversion is realized, and the imaging purpose is achieved.

LCOS based schemes: LCOS belongs to the new reflective Micro LCD (Micro LCD) projection technology, its structure is on the silicon chip, using the semiconductor process to make the driving panel (also called CMOS-LCD), then plating the aluminum on the transistor as the reflector, forming the CMOS substrate, then attaching the CMOS substrate and the upper glass substrate containing the transparent electrode, and injecting the liquid crystal. The basic principle is similar to that of the LCD, and the principle of birefringence of liquid crystal molecules is adopted. When the voltage of the aluminum electrode on the silicon substrate changes, the liquid crystal voltage changes, liquid crystal molecules deflect, the on state and the off state of incident polarized light are modulated, and images are generated.

Existing imaging schemes based on spatial light modulators such as DMD, LCD or LCOS all modulate the light intensity of image light through the spatial light modulator, thereby realizing the display of different gray scales and colors. The spatial light modulator is very inefficient in its energy use, for example, off light of DMD is not available, LCD or LCOS modulates the polarization state distribution of transmitted light by the deflection of liquid crystal molecules, and the excessive light is absorbed by the polarizing device. These spatial light modulators all have large energy loss, so a strong heat dissipation system needs to be matched, and the light source device, the imaging device or the display device based on the spatial light modulators are large in overall size and low in energy efficiency. In addition, it is difficult to obtain a display with high brightness because high energy density cannot be carried due to the limitation of heat dissipation of the spatial light modulator device itself. Due to the limitations of the spatial light modulator itself, such as leakage of off light of the DMD, and a certain conversion efficiency of the liquid crystal molecules for the polarization state conversion of the light beam and the polarizer, it is difficult to obtain a high dynamic contrast of the obtained image.

The imaging scheme based on beam scanning generally mainly uses laser as a light source, modulates the light source through an optical modulator, and realizes display imaging through a two-dimensional scanner, an optical color combination system and a projection objective. Loading a source image signal to an optical modulator, and controlling the intensity of a light beam; and simultaneously, signals of lines and fields are synchronized to the optical deflector, so that the light beams are projected to a screen or other targets at modulated intensity according to a certain rule to form a color image.

The existing light beam scanning imaging scheme mainly uses laser as a main light source, and uses a light modulator to modulate the light intensity of the light beam. Common optical modulators are electro-optic modulation and acousto-optic modulation. The three-color laser beam is changed into laser beams with different light intensities with video signals after passing through a modulator loaded with the video signals, and then the laser beams are combined into a beam through a color combination system of an optical film. And then into the X-Y scanning system. The scanning system is generally realized by combining a rotating mirror and a small-angle vibrating mirror, or by a double-rotating-mirror system and a double-vibrating mirror.

The light beam scanning imaging scheme uses a light modulator, so that the power consumption and the volume of the system are large; because the number of the adopted laser light sources is small, the requirements on the control bandwidth of a modulator and scanning equipment are high, the resolution ratio of an image is low, the obtained field angle is small, and a strong speckle effect exists.

Disclosure of Invention

An embodiment of the present application provides an imaging method, including:

decomposing a frame of target image to obtain a plurality of subframes, wherein at least one pixel of other subframes is inserted between at least two adjacent pixels of each subframe;

moving the position of a light spot emitted by a light source array module through a light spot shifting device according to the pixel position of each sub-frame and the time sequence, so that the position of the light spot sequentially corresponds to each sub-frame;

imaging light spots emitted by the light source array module corresponding to the plurality of sub-frames to obtain image light,

the light source array module comprises a plurality of light sources, light beams emitted by each light source of the plurality of light sources form light spots corresponding to one pixel of the target image, and the positions of the light spots formed by the plurality of light sources at the moment corresponding to the sub-frame correspond to the positions of the plurality of pixels contained in the sub-frame one by one.

Through the embodiments of the imaging method as described above, the beneficial effects of the present application are:

the method comprises the steps of decomposing a target image in a source image signal into a plurality of sub-frames which are sparsely sampled, and sequentially forming light spots corresponding to each sub-frame according to time sequence, wherein when one sub-frame is switched to the next sub-frame, the positions of the light spots are moved by a light spot shifting device to enable the light spots to correspond to the pixel positions of the corresponding sub-frames, so that the light spots corresponding to each light source are moved to correspond to a plurality of image pixel points in the time of displaying one frame of image. Since the overall resolution is achieved by the light source array comprising a plurality of light sources, each light source can be modulated separately to contribute to the overall resolution, and therefore, compared with the case that a single light source contributes to the overall resolution, the modulation bandwidth of the light source device is reduced. In addition, because the light spot corresponding to the single light source only needs to cover a certain area in the whole image, the control bandwidth of the light spot shifting device can be effectively reduced. In addition, since a certain region in the whole image is moved by a single light source, the embodiment of the application can effectively improve the uniformity of the image. In addition, this application embodiment uses the light source array as the light source, and when this light source is the laser, this scheme of moving the facula also can effectively weaken the speckle of the image that forms.

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 in the corresponding time period, which avoids using a spatial light modulator with low efficiency at present, and therefore, the efficiency of the imaging method can be greatly improved. In addition, since the brightness of a single pixel can be fully on/off by brightness adjustment of the light source, the embodiments can achieve high contrast and high dynamic range.

In addition, in some embodiments, each light source of the light source array module is independently addressable, i.e., independently controllable, and thus, variable light encoding can be achieved, thereby improving the accuracy of imaging. In addition, under the condition that each light source is independently controllable, the gray scale of each pixel can be realized by modulating the light intensity of the corresponding single light source, the adjusting method is simple and easy to implement, and in addition, the brightness of each pixel can be fully turned on/off by adjusting the brightness of the light source, so the embodiments can realize high contrast and high dynamic range. The lattice or structured light produced by the scheme can realize transformation rapidly, and generates a customized pattern at extremely high speed.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts. Wherein:

fig. 1 is a schematic structural view of a light source device according to an embodiment of the present application;

FIG. 2 is a diagram illustrating how a frame of a target image is decomposed into a plurality of sub-frames according to an embodiment of the present application;

FIG. 3 is a schematic diagram of an array light source of a light source array module and a close-packed pixel array formed by the array light source according to an embodiment of the present disclosure;

fig. 4 is a schematic configuration diagram of a light source device according to another embodiment of the present application;

fig. 5 is a schematic configuration diagram of a light source device according to still another embodiment of the present application;

FIG. 6 is a schematic flow diagram of an imaging method according to an embodiment of the present application;

FIG. 7 is a schematic diagram of a 3D imaging scheme based on an array of light sources according to an embodiment;

FIG. 8 is a schematic diagram of a MEMS based VCSEL light source array system according to an embodiment;

fig. 9 is a schematic structural block diagram of an imaging apparatus according to an embodiment of the present application;

fig. 10 is a schematic configuration diagram of an image forming apparatus according to another embodiment of the present application;

FIG. 11 is a graph of pulse signal versus displacement for the embodiment shown in FIG. 10;

fig. 12 is a schematic configuration diagram of an image forming apparatus according to another embodiment of the present application;

fig. 13 is a schematic configuration diagram of a display device according to an embodiment of the present application;

fig. 14 is a schematic configuration diagram of a display device according to another embodiment of the present application;

fig. 15 is a schematic configuration diagram of a display device according to still another embodiment of the present application;

FIG. 16 is a schematic diagram of a Micro LED combined light source according to an embodiment of the present application;

fig. 17 is a de-framing schematic diagram for an example image corresponding to the de-framing method shown in fig. 2.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terms "imaging technique", "imaging method", or "imaging" and the like in the present application above and below refer to a process, method, or technique of forming image light corresponding to a source image using a light source and an optical/electrical device to reproduce the source image.

The terms "image", "source image", "image signal" and the like in the context of and above this application include any form or format of image and/or video.

The terms "time of a sub-frame", "time corresponding to a sub-frame" and the like in the above and in the following in the present application refer to a time at which the sub-frame is to be displayed, a time at which a light spot corresponding to a pixel of the sub-frame is to be formed.

Fig. 1 shows a schematic structural diagram of a light source apparatus 100 according to an embodiment of the present application. As shown in fig. 1, in this embodiment, the light source apparatus 100 includes a light source array module 110, a control module 120, and a spot shifting apparatus 130. The light source array module 110 includes a plurality of light sources 111 arranged in an array form. Wherein the light beam emitted from each light source 111 forms a light spot 112 (see fig. 3) corresponding to one pixel of one frame of the target image. I.e. one pixel in the target image corresponds to one spot of the source light beam. If the number of light sources is sufficiently large, for example, the number of light sources is equal to or greater than the number of pixels of the target image, the target image can be displayed completely by forming light spots equal to the number of pixels of the target image at one time without decomposing the target image into a plurality of subframes. However, when the number of light sources is smaller than the number of pixels included in the target image, the target image needs to be divided into a plurality of subframes, and the plurality of subframes must be sequentially displayed in a time-division manner within a very short period of time. The sub-frames displayed each time contain the number of pixels equal to or less than the number of light sources, i.e. the resolution of the sub-frames is equal to or less than the light source resolution of the light source array module 110. Each of the plurality of sub-frames constituting a frame of the target image includes a portion 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. Due to the fact that the time for displaying the sub-frames is short enough, the human eyes cannot feel the switching among different sub-frames due to the phenomenon of visual persistence, and the human eyes can automatically splice the sub-frames into a complete image in one frame.

In the embodiment 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 comprises a plurality of pixels and is composed of a plurality of sub-frames, wherein the pixels contained in each sub-frame in the plurality of sub-frames are a part of the plurality of pixels contained in the target image, and the pixels contained in the plurality of sub-frames jointly form the pixels contained in the target image. In the embodiment of the present application, the sub-frames are sparsely sampled, at least one pixel of another sub-frame is inserted 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 the sub-frames are different. In one example, each sub-frame includes one or more pixels of one or more other sub-frames interposed between every two adjacent pixels.

The spot shifting device 130 is used to shift the position of the 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 spot shifting device 130 in a timing sequence such that the position of the entire spot emitted by the light source array module 110 corresponds to each sub-frame in turn. To achieve that the position of the spot corresponds to each sub-frame in turn, in one example, the control module 120 may be configured to: the light spot shifting device 130 is controlled according to the pixel position of each sub-frame, so that the positions of the light spots 112 of the light source array module 110 at the time corresponding to the sub-frame correspond to the positions of the pixels included in the sub-frame one by one.

For example, assuming that the target image includes 4 subframes S1-S4, the time T for displaying the frame of the target image is divided into four equal subframe periods T1-T4, where subframe S1 is displayed at time T1, subframe S2 is displayed at time T2, subframe S3 is displayed at time T3, and subframe S4 is displayed at time T4. As described above, the sub-frames S1-S4 are sparsely sampled, each sub-frame includes a number of pixels equal to the number of light sources 111 included in the light source array module 110, and each sub-frame S1-S4 has a different pixel location. In one embodiment of the present application, at time t1, the control module 120 controls the light spot shifting device 130 to shift the position of the light spot 112 emitted by the light source array module 110 to a position corresponding to the pixel of the sub-frame S1, i.e., such that the pixel position of the image light formed by the light spot 112 coincides with the position of the pixel contained in the sub-frame S1. In the present embodiment, when the light spot shifting device 130 shifts the light spots 112 emitted from the light source array module 110 to the positions corresponding to the sub-frame S1, the position of each light spot 112 corresponds to the position of the pixel corresponding to it in the sub-frame S1. At time t2, spot shifting apparatus 130 controls control module 120 to control spot shifting apparatus 130 to shift spot 112 emitted from light source array module 110 to a position corresponding to a pixel of sub-frame S2. From displaying one sub-frame to displaying the next sub-frame, the spot shifting device 130 shifts the spot 112 by a distance corresponding to the pixel pitch of the two sub-frames. For example, assuming that each pixel of sub-frame S2 is shifted one pixel to the right with respect to each pixel of sub-frame S1, control module 120 controls spot shifting device 130 to shift the entirety of spots 112 emitted by light source array module 110 to the right by a distance corresponding to one pixel of image light. At times t3 and t4, spot-shifting device 130 continues to move spot 112 to correspond to the positions of sub-frames S3 and S4, respectively. Thus, during the time T, the light source device 100 sequentially emits the light spots corresponding to the sub-frames S1 to S4 in time series, and the four sub-frames are viewed by the human eye as a reproduction of a complete target image of one frame due to the persistence of vision of the human eye.

In the examples described above and below herein, the distances between the corresponding pixels of the adjacent two sub-frames are the same, for example, in the example described above, each pixel in S2 is one pixel apart from the corresponding pixel in S1, so that all the spots can be moved as a whole when the spots are moved. It will be appreciated that the distance between corresponding pixels of two adjacent sub-frames may also be different, and when transitioning from one sub-frame to the next, the distance to be moved may be determined for each spot, and the spot shifting means 130 may be controlled to shift each spot or each part of spots that are moved by the same distance, respectively.

In the examples described above and below herein, the spacing between each two adjacent light sources 111 of the light source array module 110 is equal, and thus the spacing between adjacent light spots emitted by them is also equal. It will be appreciated that the spacing between adjacent light sources may be different, as may the distance between adjacent spots.

Fig. 2 shows a schematic diagram of how a frame of a target image is decomposed into a plurality of sub-frames according to an embodiment of the present application. In the embodiment of the present application, how to decompose the target image into a plurality of sub-frames may be determined according to the number of pixels of the target image, the number of light sources included in the light source array module, the interval between the light sources, and other factors. In one example, assuming that the plurality of light sources of the light source array module 110 form an M × N array (M and N are both greater than 1), the emitted light spots are also an M × N array (as shown in fig. 3), and the target image S includes X × Y pixels (X is greater than M and Y is greater than N), then the target image S may be decomposed into a × b subframes, where a is X/M and b is Y/N. In the example of FIG. 2, where the light source array module 110 is a 3 × 3 light source array and the target image contains 6 × 6 pixels, the target image S may be decomposed into 2 × 2 sub-frames S1-S4.

In the embodiment of the present application, the density of the array formed by arranging the plurality of light sources 111 of the light source array module 110 is less than the density of the pixel distribution of the target image, and the array formed by arranging the plurality of light sources 111 is a sparse lattice with respect to the pixel distribution of the target image, that is, the plurality of light spots emitted by the light sources 111 are imaged and correspond to non-adjacent pixels, which are not adjacent pixels of the image, but are spaced by one or more other pixels. In the example of fig. 2, assuming that the interval between every two adjacent light sources 111 is such that the light spots emitted by the two adjacent light sources 111 are formed by imaging 1 pixel apart, the positions of the four sub-frames S1-S4 into which the target image S is decomposed in the target image S are as shown in fig. 2. In fig. 2, each square represents a pixel, and the number in the square represents the subframe number to which the pixel belongs, for example, the number "1" represents the subframe S1, the number "2" represents the subframe S2, the number "3" represents the subframe S3, and the number "4" represents the subframe S4. In the example of FIG. 2, the target image S is decomposed into four sub-frames S1-S4 that are displayed in chronological order, with each sub-frame separated from the next by a distance of one pixel. After displaying the sub-frame S1 at time t1, at time t2, the control module 120 controls the light spot shifting device 130 to shift the light spot 112 emitted from the light source array module 110 to the right as a whole by a distance corresponding to one pixel of the image light to form a sub-frame S2; at time t3, control module 120 controls spot shifting device 130 to shift the entire spot 112 emitted by light source array module 110 downward by a distance corresponding to one pixel of image light and to continue to shift rightward by a distance corresponding to one pixel of image light to form sub-frame S3; at time t4, control module 120 controls spot shifting device 130 to shift spot 112 emitted by light source array module 110 entirely rightward by a distance corresponding to one pixel of image light to form sub-frame S4. In the example of FIG. 2, the four sub-frames are displayed in the order S1 → S2 → S3 → S4, it being understood that the four sub-frames may be displayed in other orders, resulting in a reproduction of the complete target image. In the example of FIG. 2, the pixels of sub-frames S1-S4 are arranged together as closely-spaced pixels. By the embodiment of the application, the sparse array light source can be effectively projected into a high-resolution implementation scheme, and the M × N arranged sparse light source array can be scanned into aM × bN closely-arranged light spots with equal intervals, as shown in FIG. 3.

In the embodiment of the present application, when controlling the light spot shifting device 130 to shift the light spots 112 emitted by the light source array module 110 to correspond to the position of each sub-frame, the control module 120 further 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 each light spot of the light source 111 forms a gray scale display of a corresponding pixel of the sub-frame at the time corresponding to the sub-frame. For example, the control module 120 may adjust the brightness of the light source 111 by adjusting or modulating a driving current or a driving voltage of the light source 111. In the embodiment of the present application, each pixel of the image light corresponds to each light spot 112 emitted by the light source array module 110, and each light spot 112 is emitted by only one light source, so that each pixel of the image light is associated with only one corresponding light source and is independent of other light sources. In one example, each light source 111 can be independently controlled or driven, the gray scale of each pixel of the formed image light is only related to a corresponding unique light source, and 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 scale of the formed image.

According to the light source device, a target image in a source image signal is decomposed into a plurality of sub-frames which are sparsely sampled (namely at least one pixel of other sub-frames is inserted between at least two adjacent pixels of each sub-frame), the pixels of each sub-frame correspond to the light sources of the light source array module one by one, and light spots corresponding to each sub-frame are sequentially formed according to time sequence, wherein when one sub-frame is switched to the next sub-frame, the positions of the light spots are shifted through the light spot shifting device so as to correspond to the pixel positions of the corresponding sub-frames. In 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 the light source array comprising a plurality of light sources, each light source can be modulated separately to contribute to the overall resolution, and therefore, compared with the case that a single light source contributes to the overall resolution, the modulation bandwidth of the light source device is reduced. In addition, because the light spot corresponding to the single light source only needs to cover a certain area in the whole image, the control bandwidth of the light spot shifting device can be effectively reduced. In addition, since a certain region in the whole image is moved by a single light source, the embodiment of the application can effectively improve the uniformity of the image. In addition, this application embodiment uses the light source array as the light source, and when this light source is the laser, this scheme of moving the facula also can effectively weaken the speckle of the image that forms.

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 in the corresponding time period, so that the currently inefficient spatial light modulator is avoided, and thus the efficiency of the light source device can be greatly improved. In addition, since the brightness of a single pixel can be fully on/off by brightness adjustment of the light source, the embodiments can achieve high contrast and high dynamic range.

Fig. 4 shows a schematic configuration diagram of a light source device 100 according to another embodiment of the present application. In the embodiment of fig. 4, unlike the embodiment of fig. 1, the control module 120 may include three parts: processor 121, light source driver 122, and spot shift control unit 123, wherein:

the processor 121 is configured to perform image processing on the received source image signal, resulting in a target image comprising a plurality of subframes. The image processing performed by the processor 121 may include one or more of format conversion, decoding, filtering, amplifying, etc. of the received source image signal, and may further include obtaining a target image from the source image signal and decomposing the target image into a plurality of subframes matched with the light source device 100 according to the number of pixels of the target image and configuration parameters of the light source device 100. The configuration parameters of the light source device 100 may include the number and the interval of the light sources of the light source array module 110. The processor 121 sends the decomposed sub-frame signals and the corresponding timings of the sub-frames to the light source driver 122 and the light spot shift control unit 123.

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 the plurality of subframes. In one example, the light source driver 122 generates a corresponding driving signal for the light source 111 corresponding to each pixel according to the gray scale of the pixel of each sub-frame, and the driving signal enables the brightness of the light emitted by the light source 111 to be consistent with the gray scale of the pixel. In this way, the light source driver 122 can drive the light source 111 to generate a light spot with corresponding brightness for each sub-frame at the time of the sub-frame. In some examples, where the number of light spots required for a sub-frame is less than the number of light sources, some light sources may not emit light, i.e., the light source driver 122 does not generate a drive signal for them.

The spot shift control unit 123 is configured to generate a signal for controlling the spot shifting device 130 to move the spot 112 according to the signals of the plurality of subframes. For example, the light spot shift control unit 123 controls the light spot shifting device 130 to shift the light spots formed by the light source array module 110 to correspond to the pixel positions of the sub-frame one by one at the time of each sub-frame.

The light spot shifting means 130 shifts the positions of the light spots formed by the light source array module 110 in accordance with an instruction from the control module 120 or the light spot shift control unit 123 so that the positions of the light spots formed by shifting the light source array module 110 at the time of each sub-frame correspond one-to-one to the positions of the pixels of the sub-frame. The "time of each sub-frame" in the above and in the following of the present application refers to a time at which each sub-frame is reproduced in time series, that is, a time at which a light spot corresponding to the sub-frame is formed, at which the corresponding light spot is moved to a position corresponding to the sub-frame, and the luminance of each light spot coincides with the gray scale of each pixel of the sub-frame.

In one example, the spot-shifting device 130 may 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, a first one-dimensional micro-actuator being capable of moving in a first direction, and a second one-dimensional micro-actuator being capable of moving in a second direction. The light sources 111 of the light source array module 110 may be attached to the micro-actuator, and the micro-actuator moves under the instruction of the control module 120 or the light spot displacement control unit 123, so as to drive the light sources 111 to move, thereby changing the positions of the light sources 111. The light sources 111 of the light source array module 110 may be fixed to a two-dimensional micro-actuator or two one-dimensional micro-actuators as a whole, and the movement of the micro-actuators may drive the light source array module 110 to move as a whole. Alternatively, the light source array module 110 may be divided into a plurality of sections, each section including one or more light sources 111, each section being fixed to one two-dimensional micro-actuator or two one-dimensional micro-actuators, respectively. The two-dimensional micro actuator can be a two-dimensional deflection table, 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 table. The micro-actuator may be linear, deflectable, or other type of motion. The two-dimensional microactuator may be moved at the same or different speeds in the two directions, e.g., with a faster movement in a first direction than in a second direction. Alternatively, the two one-dimensional micro-actuators may be moved at the same or different speeds, e.g., one-dimensional micro-actuators moving in a first direction faster than one-dimensional micro-actuators moving in a second direction.

In another example, the spot-shifting device 130 may change the position of the spot 112 by deflecting the propagation direction of the light beam emitted by the light source array module 110. The beam deflecting means is, for example, a MEMS scanning mirror or a phase deflecting device.

In one embodiment of the present application, to ensure consistency of the movement of the spot position and the adjustment of the spot brightness, the control module 120 may further include a synchronization unit 124. The synchronization unit 124 is configured to control the light source driver 122 to synchronize with the light spot shifting device 130 according to the plurality of sub-frames, such that the light source driver 122 drives the light source array module 110 to emit light corresponding to the gray scale distribution of each of the plurality of sub-frames while the light spot shifting device 130 moves the light spots 112 of the plurality of light sources 111 to a position corresponding to the sub-frame. The synchronization unit 124 is connected to the processor 121, the light source driver 122 and the spot shift control unit 123. The control module 120 may send each subframe and corresponding timing to the synchronization unit 124. In one example, the synchronization unit 124 may ensure 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 according to the timing of each sub-frame, so that each light source 111 emits light under the driving of the light source driver 122 while the light spot shifting device 130 drives the light spot to shift to the position corresponding to each sub-frame, and the brightness of the emitted light spot 112 is consistent with each pixel gray scale of the sub-frame. The synchronization unit 124 can ensure that the light source 111 neither emits light in advance nor in delay, but emits light of a corresponding brightness while the spot is shifted to the target position.

In one example, the light source 111 is a laser light source, and the light source driver 122 emits a pulse driving 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 pulses driving the laser light source 111 and the movement of the spot shifting device 130 such that the laser light source 111 emits equally spaced spots with the movement of the spot shifting device 130.

In the embodiment of fig. 4, the control module 120 is divided into four functional modules: a processor 121, a light source driver 122, a spot shift control unit 123, and a synchronization unit 124. It is understood that the division is based on logical division of functions, the control module 120 can be divided into other different logical functional modules, and the number of the divided functional modules can be more or less.

The light source 111 may be various light source devices capable of emitting light. For example, each light source 111 may be a vertical cavity surface emitting laser, an edge emitting laser, an LED, a Micro LED, or the like.

In the above embodiment, each light source 111 of the light source array module 110 may emit a monochromatic light spot or a white light spot.

Fig. 5 shows a schematic configuration diagram of a light source device 100 according to still another embodiment of the present application. As shown in fig. 5, the embodiment is different from the embodiment shown in fig. 1 in 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, wherein the first light source array module 110A includes a plurality of first light sources 111A emitting light having a first color, the second light source array module 110B includes a plurality of second light sources 111B emitting light having a second color, and the third light source array module 110C includes a plurality of third light sources 111C emitting light having a third color. For example, the first, second, and third colors may be blue, green, and red, respectively. In an example (as shown in fig. 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, and three light spots with three colors respectively emitted by each first light source 111A and one second light source 111B and one third light source 111C corresponding to the position may be combined into one white light spot by the light combining module 140 to serve as imaging light. Thus, the three monochromatic light spot arrays emitted by the three light source array modules are finally combined into a mixed color light spot array, such as a white light spot array, by the light combining module 140. In another example, the light source device 100 may not have the light combining module 140, and each of the first light sources 111A and the corresponding one of the second light sources 111B and one of the third light sources 111C may be arranged in the same position as three sub-pixels in close proximity, so that 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.

In the embodiment shown in fig. 5, the spot shifting means 130 may accordingly include a first spot shifting means 130A for moving the spot of the first light source array module 110A, a second spot shifting means 130B for moving the spot of the second light source array module 110B, and a third spot shifting means 130C for moving the spot of the third light source array module 110C. The control module 120 may be configured to: the first light spot shifting device 130A, the second light spot shifting device 130B, and the third light spot shifting device 130C are sequentially or simultaneously controlled according to the pixel position of each sub-frame, so that the positions of the light spots of the plurality of first light sources 111A, the second light sources 111B, and the third light sources 111C at the time corresponding to the sub-frame correspond to the positions of the pixels included in the sub-frame one to one.

Each subframe of the target image may be decomposed into a first subframe component having a first color component, a second subframe component having a second color component, and a third subframe component having a third color component, and the control module 120 may be further configured to:

controlling the luminance of each of the plurality of first light sources 111A independently according to the gradation distribution of the first subframe component so that each spot of the plurality of first light sources 111A forms a gradation display of the first subframe component at a timing corresponding to the subframe; that is, at the time corresponding to the sub-frame, the brightness of each light spot of the first light source 111A corresponds to the gray-scale value of the first color component of each pixel of the sub-frame.

Independently controlling the luminance of each of the plurality of second light sources 111B according to the gradation distribution of the second subframe component so that each spot of the plurality of second light sources 111B forms a gradation display of the second subframe component at a timing corresponding to the subframe; that is, at the time corresponding to the sub-frame, the brightness of each light spot of the second light source 111B corresponds to the gray-scale value of the second color component of each pixel of the sub-frame.

The luminance of each of the plurality of third light sources 111C is independently controlled according to the gradation distribution of the third sub-frame component so that each spot of the plurality of third light sources 111C forms a gradation display of the third sub-frame component at a timing corresponding to the sub-frame. That is, at the time corresponding to the sub-frame, the brightness of each light spot of the third light source 111C corresponds to the gray-scale value of the third color component of each pixel of the sub-frame.

How to adjust the brightness of the light source with the corresponding color to correspond to the gray scale value of the color component of the sub-frame pixel is the same as the method for adjusting the brightness of the light source to be consistent with the gray scale value of the sub-frame pixel, and the details are not repeated herein.

It is understood that the control module 120 in the embodiment of fig. 5 may also further include the processor 121, the light source driver 122, and the light spot shift control unit 123 shown in fig. 4, and may also include the synchronization unit 124, which is not described herein again.

According to the light source device of the embodiment of the application, the modulation bandwidth of the light source device can be reduced, the control bandwidth of the light spot shifting device is effectively reduced, the uniformity of the image is effectively improved, and when the light source is laser, the speckle of the formed image can be effectively weakened through the light spot shifting scheme. In addition, in some embodiments, for a single pixel in the image, the gray scale display of the pixel may be achieved by adjusting the brightness of the light source corresponding to the pixel, such that a two-dimensional gray scale distribution for each sub-frame may be achieved by adjusting the brightness of the light sources at the respective time of each sub-frame.

According to another aspect of the embodiments of the present application, there is also provided an imaging method, which may be implemented by a light source device, where the light source device is capable of decomposing a target image into a plurality of sparsely sampled subframes, and includes a plurality of light sources, each light spot emitted by the plurality of light sources corresponds to each pixel of one subframe in a one-to-one manner, and the light source device sequentially generates a corresponding light spot array for each subframe within one frame time by moving the light spots, so as to obtain image light of the target image. The light source device may be, for example, any of the embodiments of the light source device 100 described above. FIG. 6 shows a schematic flow diagram of an imaging method according to an embodiment of the present application. As shown in fig. 6, the exemplary imaging method includes the steps of:

s610: and decomposing a frame of target image to obtain a plurality of subframes.

At least one pixel of the other sub-frame is inserted between at least two adjacent pixels of each sub-frame.

For example, after receiving the target image, a control module (e.g., the control module 120 in fig. 1, 4, and 5) of the light source apparatus decomposes the target image frame. For example, the control module may decompose the target image according to the number of pixels of the target image, configuration parameters of the light source device, and the like. 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 may be decomposed into a × b subframes, where X ═ M × a and Y ═ N × b make the number of pixels of the subframes equal to the number of light sources of the light source array module, and each pixel of the subframes corresponds to one light source.

The specific decomposition method and details can refer to those in the foregoing embodiments of the light source device, and are not described herein again.

A target image comprising a plurality of pixels is decomposed into a plurality of sparsely sampled sub-frames with at least one pixel of the other sub-frames interleaved between at least two adjacent pixels of each sub-frame. The light source device generates a corresponding light spot in step S620 according to the information of the plurality of sub-frames.

S620: and moving the position of the light spot emitted by the light source array module through the light spot shifting device according to the pixel position of each sub-frame and the time sequence, so that the position of the light spot sequentially corresponds to each sub-frame.

In step S620, the light source device sequentially generates corresponding light spots for each sub-frame according to the pixel positions of the sub-frames into which the light source device is decomposed. Generating the corresponding light spots for the sub-frame may refer to moving the positions of the light spots to correspond the positions of the pixels of the sub-frame one to one by shifting the positions of the light spots at the time of the sub-frame.

The light source array module comprises a plurality of light sources, light beams emitted by each light source of the plurality of light sources form light spots corresponding to one pixel of the target image, and the positions of the light spots formed by the plurality of light sources at the moment corresponding to the sub-frame correspond to the positions of the plurality of pixels contained in the sub-frame one by one. Each sub-frame is generated by sparse sampling of the target image, and accordingly, the light sources included in the light source array module are also sparse lattice with respect to the pixel distribution of the target image.

In one example, step S620 may be implemented by the light source device by:

s621: generating a shift control signal for controlling the light spot shifting device to shift the light spot to reach a position corresponding to each sub-frame according to the pixel position of each sub-frame;

s622: and shifting the position of the light spot by the light spot shifting device according to the shifting control signal of each sub-frame.

Step S621 may be implemented by, for example, the control module of the light source apparatus or the spot shift control unit of the control module in the previous embodiment of the light source apparatus. For example, the target position to which the light spot is to be moved may be determined according to the position of each pixel of each sub-frame, the moving distance, moving direction, moving route, and the like of the light spot may be further determined according to the target position and the current position of the light spot, and then the corresponding shift control signal may be 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 that the light beam emitted by the light source needs to deflect, etc. can be determined, and the information can be included in the displacement control signal.

In step S622, the light spot shifting device of the light source device shifts the light spots according to the shift control signal, so that the positions of the light spots correspond to the positions of the pixels of the corresponding sub-frame one by one. The spot shifting device can shift the position of the spot by shifting the positions of the plurality of light sources, and can also shift the position of the spot formed by the light beams by deflecting the directions of the light beams emitted by the plurality of light sources.

As to how to generate the corresponding light spots for each sub-frame in turn by the light spot shifting according to the pixel position of each sub-frame, reference may be made to the description in the foregoing embodiments of the light source apparatus.

In one example, generating the corresponding spot for the subframe may further include: and at the moment of the sub-frame, when the light spots are shifted to the positions corresponding to the sub-frame, adjusting the brightness of each light spot to be consistent with the gray scale of each pixel of the sub-frame. That is, the example imaging method may further include the steps of: and controlling the brightness of each light source in the plurality of light sources according to the gray scale distribution of each sub-frame, so that each light spot of the plurality of light sources forms the gray scale display of the corresponding pixel of the sub-frame at the moment corresponding to the sub-frame. This step can be realized by:

determining the brightness of each light source in the light source array module at the moment of each subframe according to the gray scale distribution of each subframe;

generating a driving signal for each light source according to the determined brightness of each light source to drive the light source to emit light with the determined brightness;

at the moment of each sub-frame, a plurality of light sources emit light under the drive of corresponding drive signals to form light spots corresponding to the sub-frame.

The light source may be any light emitting device, such as a vertical cavity surface emitting laser, an edge emitting laser, an LED, or a Micro LED. In one example, each of the plurality of light sources is a pulse-driven laser light source configured to emit light when the spot shifting device shifts the spot to the target position. For example, the timing of the pulses driving the laser light source and the movement of the spot shifting device may be controlled such that the laser light source emits equally spaced spots as the spot shifting device moves.

In one embodiment, the spot shift and the light source illumination may be synchronized in order to obtain an accurate correspondence between spot position and spot brightness. For example, the above-described example imaging method may further include the steps of: and controlling the light source driver to be synchronous with the light spot shifting device according to the plurality of sub-frames, so that when the light spot shifting device moves the light spots of the plurality of light sources to the position corresponding to each sub-frame in 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 the sub-frame. By the synchronization step, the position shift of the light spot is kept consistent with the brightness variation, so that the light spot with accurate brightness can be provided at an accurate pixel position.

After forming the light spot corresponding to each sub-frame, the example imaging method proceeds to step S630.

S630: and imaging light spots corresponding to the plurality of sub-frames and emitted by the light source array module to obtain image light.

In step S630, the light spot may be imaged by the imaging module to obtain image light. The imaging module may be a module in the light source device, or may be a module located outside the light source device.

In the above embodiments, 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 including a plurality of first light sources emitting light having a first color, a second light source array module including a plurality of second light sources emitting light having a second color, and a third light source array module including a plurality of third light sources emitting light having a third color.

The light spot shifting device comprises a first light spot shifting device used for shifting the light spot of the first light source array module, a second light spot shifting device used for shifting the light spot of the second light source array module and a third light spot shifting device used for shifting the light spot of the third light source array module.

In this case, step S620 may include: and 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 position of each subframe, so that the positions of the light spots of the plurality of first light sources, the plurality of second light sources and the plurality of third light sources are in one-to-one correspondence with the positions of the pixels contained in the subframe at the moment corresponding to the subframe.

In this embodiment, each sub-frame of the target image may 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, and controlling the luminance of each of the plurality of light sources according to the gray scale distribution of each sub-frame includes:

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 each light spot of the plurality of first light sources forms a gray scale display of the first sub-frame component at a time corresponding to the sub-frame; that is, at the time corresponding to the sub-frame, the luminance of each spot corresponds one-to-one to the gray-scale value of the first color component of each pixel of the sub-frame.

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 each light spot of the plurality of second light sources forms a gray scale display of the second sub-frame component at a time corresponding to the sub-frame; that is, at the time corresponding to the sub-frame, the luminance of each spot corresponds one-to-one to the gray-scale value of the second color component of each pixel of the sub-frame.

And controlling the brightness of each light source in the plurality of third light sources according to the gray scale distribution of the third sub-frame component, so that each light spot of the plurality of third light sources forms gray scale display of the third sub-frame component at the moment corresponding to the sub-frame. That is, at the time corresponding to the sub-frame, the luminance of each spot corresponds one-to-one to the gray-scale value of the third color component of each pixel of the sub-frame.

In the case where the light source array module as described above emits a plurality of monochromatic lights, before the imaging step S630, the example imaging method further includes the steps of: and combining the light spots of the plurality of first light sources, the plurality of second light sources and the plurality of third light sources. In this step, for a light source group consisting of a first light source, a second light source and a third light source with corresponding positions, the light combining module may be used to combine three light spots emitted by the group of light sources into one light spot. In this way, the three single-color light spot arrays emitted by the three light source array modules are finally combined into a mixed color light spot array by the light combination module, such as a white light spot array. Then, in step S630, the combined light spot is imaged to obtain image light.

For the details of the above steps or processes, reference may be made to the foregoing embodiments of the light source device, which are not described herein again. Conversely, the descriptions in the embodiments of the imaging method are also made as references to the embodiments of the light source device described above.

By the imaging method according to the embodiment of the application, a target image in a source image signal can be decomposed into a plurality of sparsely sampled sub-frames (namely, at least one pixel of other sub-frames is inserted between at least two adjacent pixels of each sub-frame), the pixels of each sub-frame correspond to the light sources of the light source array module one by one, and light spots corresponding to each sub-frame are sequentially formed according to a time sequence, wherein when switching from one sub-frame to the next sub-frame, the positions of the light spots are moved by the light spot shifting device to correspond to the pixel positions of the corresponding sub-frames. In 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 the light source array comprising a plurality of light sources, each light source can be modulated separately to contribute to the overall resolution, and therefore, compared with the case that a single light source contributes to the overall resolution, the modulation bandwidth of the light source device is reduced. In addition, because the light spot corresponding to the single light source only needs to cover a certain area in the whole image, the control bandwidth of the light spot shifting device can be effectively reduced. In addition, since a certain region in the whole image is moved by a single light source, the embodiment of the application can effectively improve the uniformity of the image. In addition, this application embodiment uses the light source array as the light source, and when this light source is the laser, this scheme of moving the facula also can effectively weaken the speckle of the image that forms.

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 in the corresponding time period, so that the currently inefficient spatial light modulator is avoided, and therefore, the efficiency of the imaging method can be greatly improved. In addition, since the brightness of a single pixel can be fully on/off by brightness adjustment of the light source, the embodiments can achieve high contrast and high dynamic range.

In addition, in some imaging method embodiments, each light source of the light source array module is independently addressable, i.e., independently controllable, and thus, variable light encoding can be achieved, thereby improving the accuracy of imaging. In addition, under the condition that 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, and the adjusting method is simple and easy to implement. In addition, since the brightness of a single pixel can be fully on/off by brightness adjustment of the light source, the embodiments can achieve high contrast and high dynamic range. The lattice or structured light produced by the scheme can realize transformation rapidly, and generates a customized pattern at extremely high speed.

The embodiments of the above-described example light source apparatus and example imaging methods may be applied in many contexts, for example, for projection image display, or for 3D imaging of objects.

In the projection image display application, the image light obtained in step S630 may be projected onto a screen so that the target image is reproduced on the screen. In such an application, the embodiments of the light source device may be integrated into a display device, and the display device may further include an imaging module for imaging the light spot emitted from the light source device to obtain image light and projecting the image light onto a screen.

In the object 3D imaging application, the image light obtained in S630 may be used as the structured light, and the exemplary imaging method may next include the steps of:

irradiating image light onto an object to be measured; collecting image light modulated by an object to be detected; and processing the acquired modulated image light to obtain the three-dimensional information of the object to be detected.

In such an application, the embodiments of the light source apparatus described above may be integrated in an imaging apparatus for 3D imaging of an object to be measured, and the imaging apparatus may further include:

and the imaging module is used for forming image light based on the light spots output by the light source device and irradiating the image light onto the object to be measured.

And the acquisition module is used for acquiring the image light modulated by the object to be detected.

And the image processing module is used for processing the modulated image light acquired by the acquisition module to obtain the three-dimensional information of the object to be detected.

Hereinafter, example embodiments of an imaging device and a display device will be described in detail, respectively.

The 3D imaging technique can achieve 2D imaging of a target object and also obtain information of the target in a depth dimension, and thus can achieve 3D stereoscopic scanning or modeling. Common 3D imaging schemes may include Diffraction Optical Element (DOE), scanning schemes for 3D structured Light, 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), among others.

However, the regulation and control of the projected structured light are mainly realized by a plurality of closely arranged light source arrays, DOEs and some spatial processing, the light sources do not realize independent addressing control, the number of images which can be regulated and controlled is limited, the images cannot be dynamically modulated, and the accuracy and the resolution which can be achieved are limited; when a Digital Micromirror Device (DMD) is used for realizing a 3D structured light scheme based on DLP, the efficiency of the DMD spatial light modulator is low, and a required heat dissipation module is large, so that the whole system is complex, large in size and low in efficiency.

At present, regular and irregular light source arrays are used more often, or a plurality of light source arrays are applied to project light spots with different sparseness and different arrangements, a light beam is received and collimated by a lens unit (such as a micro lens array or a lens group) and then projected to a space, and then the light beam emitted by the light source array is copied and amplified by different multiples by one or more DOEs, such as a 3D imaging scheme based on the light source array shown in fig. 7, so as to realize structured light for different application scenes; the multiple light source arrays can also be processed by one or more combinations of translation, rotation, mirror image or scaling, and the like, aiming at obtaining laser speckle images with uniform particle overall distribution and high local uncorrelated degree so as to obtain higher precision.

The VCSEL light source array system based on MEMS reflects array beams emitted from regular or irregular VCSELs by the MEMS micro-mirror vibration and projects them onto an object in the form of a lattice, aiming to copy the VCSEL lattice by the MEMS fast scanning, to realize denser light spot distribution and improve accuracy, as shown in fig. 8; the regulation and control of the projected structured light are mainly realized by a plurality of closely arranged light source arrays, DOEs and some spatial processing, the independent addressing control of the light sources is not realized, the number of images which can be regulated and controlled is limited, the images cannot be dynamically modulated, and the accuracy and the resolution which can be achieved are limited.

For a 3D structured light scheme based on DLP, when a designer needs to perform rapid high-precision scanning with millimeter to micron resolution, the DLP-based structured light system is often selected, and high-speed real-time 3D scanning is realized by using a DMD (digital micromirror device), but the efficiency of the DMD spatial light modulator is low, and a required heat dissipation module is large, so that the whole system is complex, large in size and low in efficiency.

Fig. 9 shows a schematic structural block diagram of an imaging apparatus according to an embodiment of the present application. As shown in fig. 9, the imaging apparatus 900 includes a light source apparatus 100, an imaging module 920, an acquisition module 930, and an image processing module 940. 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 may be each of the light source device embodiments as previously described. In the embodiment of fig. 9, the control module of the light source apparatus is divided into a decoder 911 and a light source array driving module 912, and the beam scanning/deflecting actuator 913 corresponds to the spot shifting apparatus 130 in the foregoing light source apparatus embodiment.

The light source array module 110 in the test pattern generation module 910 uses a driver having electrodes for independently controlling each light source to realize fast single-point control of each laser light source. Since the array light sources of the light source array module 110 need to be independently addressed and controlled, the array is arranged in a sparse lattice form as an M × N lattice, as shown in fig. 4. Through the optical imaging lens of the imaging module 920, M × N sparse pixel points can be implemented on the screen. In order to display a frame of image with densely arranged pixels, one frame of image needs to be split into a sub-frames displayed in a time division multiplexing mode, namely, light spots corresponding to each independently addressing controlled light source are expanded into the densely arranged a-b light spots through time division multiplexing, and the closely arranged pixels corresponding to the a-b pixels in one frame of image just fill the gaps between the adjacent independently addressing controlled light sources. In the time of one frame, the switching between the display sub-frames is realized by a micro-actuator, and finally aM bN pixel points are realized on the screen. Because the switching time between the sub-frames is far longer than the minimum time that the persistence of vision of human eyes can respond, the integral effect of human eyes splices a plurality of sub-frames into a complete image. The above description divides a frame of image into a × b non-overlapping subframes, where a × b subframes are repeated only once in a frame, and the principle of repeating a × b subframes multiple times is similar, and only the micro-actuator control rate needs to be increased, which is not described here again.

The detailed frame splitting diagram corresponds to the case where a is 2 and b is 2 as shown in fig. 3. the sparse lattice light source is located at position 1 at time t1, at position 2 at time t2, and so on. The light sources are located at

positions

1, 2, 3, 4 in sequence during a frame time, and each light source constitutes 2 x 2 closely-spaced pixels that do not overlap, forming 2M x 2N pixels as a whole.

The video signal source is converted by the decoder 911 and then transmitted to the light source array driving module 912, and different gray scales are realized by controlling the brightness of the light source at each light spot position, so that the regulation and control of a subframe image are completed. At this time, the image capturing module 930 captures the image and transmits the image to the image processing module 940 for analysis. When the sub-frame is the other sub-frame, the light beam scanning/deflecting actuator 913 moves the light spot corresponding to the array light source to the corresponding position, and the light source array driving module 912 drives the array light source according to the gray scale corresponding to the sub-frame, so that the gray scale distribution of the corresponding sub-frame is displayed on the image. The image acquisition module 930 acquires the image and then passes the image to the image processing module 940 for analysis. Finally, the image processing module 940 analyzes and compares all the displayed images to realize high-precision 3D imaging.

Fig. 10 is a schematic block diagram of an imaging apparatus 1000 according to another embodiment of the present application, in which individually addressable VCSELs are used as array light sources of a light source array module, and a micro actuator 1010 is used as a spot shifting apparatus to vibrate the light source array module 110 to realize spot shifting. The decoder 1021, VCSEL driver 1022, microactuator driver 1023, and synchronization device 1024 correspond to the processor 121, light source driver 122, spot shift controller 123, and synchronization unit 124, respectively, which constitute the control module 120.

After being decoded by the decoder 1021, the video source is transmitted to the VCSEL driver 1022 and the microactuator driver 1023, and synchronization is ensured by the synchronization device 1024. The VCSEL light sources of the light source array module 110 are mounted on the micro-actuator 1010. The micro-actuator 1010 may be a two-dimensional micro-actuator, or may be two one-dimensional micro-actuators, and the two one-dimensional micro-actuators respectively control two directions perpendicular to each other, so that the VCSEL has two-directional vibrations. The two-dimensional vibration directions may be one of a fast frequency and a slow frequency. Wherein, the slow frequency direction adopts the step mode vibration. The micro-actuator 1010 may be a linear actuator or a rotary actuator. The laser source VCSEL is pulsed to emit light when the microactuator 1010 is moved to the desired spot position. For example, the diameter of a single light source of a VCSEL 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, and the whole VCSEL light source array is about 30mm long and about 15mm wide. A resolution of 2k and a refresh rate of 60Hz can be achieved when the vibration frequency in the x-direction is 600Hz and the vibration frequency in the y-direction is 60 Hz. In the case of two one-dimensional micro-actuators, the one-dimensional micro-actuator in the x direction may be a high-frequency piezoceramic actuator, and the one-dimensional micro-actuator in the y direction may be, but is not limited to, a piezoelectric moving platform, a piezoelectric stepper motor, or a one-dimensional deflection stage. In the case of a two-dimensional microactuator, the two-dimensional microactuator can use a high-frequency two-dimensional deflection stage to simultaneously effect deflection in two directions. The pulse timing of the laser source can be controlled to match the displacement curve of the micro-actuator 1010, so that the VCSEL projects light spots with equal spacing. For example, when the shift curve is a sine wave, by modulating the pulse timing, an equally spaced output can be achieved, as shown in fig. 11. When a subframe arrives, the micro-actuator 1010 moves the light spot corresponding to the array light source to the corresponding position, and the VCSEL driver 1022 drives the array light source according to the gray scale corresponding to the subframe, so that the gray scale distribution of the corresponding subframe is displayed on the image. The obtained densely arranged pixel points are optically amplified by the imaging module 920 and finally projected onto an object to be measured. The collecting module 930 collects the light modulated by the object, transmits the signal to the image processing module 940, and the image processing module 940 calculates the signal to obtain the three-dimensional information of the object to be measured.

According to the embodiment, the vibration bandwidth of the two-dimensional micro actuator is reduced through the sparse dot matrix light source, the system is simple, the size is small, the resolution ratio is high, the modulation of the image can be realized without an additional spatial light modulator, and high-precision 3D imaging is realized.

Fig. 12 shows a schematic block diagram of an imaging device 1200 according to another embodiment of the present application, in which Micro LEDs are used as sparse array light sources of a light source array module, and a MEMS scanning mirror or a phase deflection device is used to realize beam scanning/spot shifting. The decoder 1221, the LED driver 1222, the scanning device driver 1223, and the synchronizing device 1224 correspond to the processor 121, the light source driver 122, the spot displacement controller 123, and the synchronizing unit 124, respectively, which constitute the control module 120.

As shown in fig. 12, 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 between the two is ensured by the synchronization device 1224. The phase deflector/MEMS mirror 1230 as spot-shifting means functions to effect beam deflection. The phase deflector uses the principle of diffraction of light to deflect the main light level by modulating the phase of the light, typical devices such as acousto-optic deflectors and liquid crystals. The MEMS adopts piezoelectric ceramics as a driving source, can realize two-dimensional rapid turnover, and realizes beam deflection by using the reflection principle of light.

For example, the diameter of the Micro LED single light source of the LED light source array 1210 is 15 micrometers, the pitch of each light source in the x and y directions is 150 micrometers, there are 200 light sources in the x direction and 100 light sources in the y direction, and the whole Micro LED light source array is about 30mm long and about 15mm wide. A resolution of 2k and a refresh rate of 60Hz can be achieved when the scanning frequency in the x-direction is 600Hz and the scanning frequency in the y-direction is 60 Hz. When the acousto-optic deflector is used as a light beam deflection device, because the response time of the acousto-optic deflector is in ns level, the densely arranged pixel point arrangement can be realized without pulse driving of a light source. When a sub-frame is reached, the phase deflector/MEMS mirror 1230, under the driving of the scanning device driver 1223, moves the light spot of the LED light source array 1210 to the position corresponding to the sub-frame, and the LED driver 1222 drives the LED light source array 1210 according to the gray scale corresponding to the sub-frame, so that the gray scale distribution of the corresponding sub-frame is displayed on the image. The obtained densely arranged pixel points are optically amplified by the imaging module 920 and finally projected onto an object to be measured. The collecting module 930 collects the light modulated by the object, transmits the signal to the image processing module 940, and the image processing module 940 calculates the signal to obtain the three-dimensional information of the object.

The embodiment utilizes a sparse lattice light source, has simple system, small volume and high resolution, can realize the modulation of the image without an additional spatial light modulator, and realizes high-precision 3D imaging.

Fig. 13 shows a schematic configuration diagram of a display device according to an embodiment of the present application. As shown in fig. 13, the exemplary display device 1300 is composed of 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. The decoder 1321 and the light source array driver 1322 constitute the control module 120 in each embodiment of the light source apparatus as described above, the beam scanning/deflecting actuator 1330 is equivalent to the spot shifting apparatus 130 in each embodiment of the light source apparatus as described above, and the light source array module 1310, the decoder 1321, the beam scanning/deflecting actuator 1330 and the light source array driver 1322 constitute the light source apparatus module in each embodiment of the light source apparatus as described above.

As shown in fig. 13, the array light sources of the light source array module 1310 use electrodes with independent control of each light source, and fast single point control of each laser light source is achieved by the light source array driver 1322. Since the array light sources need to be independently addressed and controlled, the array light sources of the light source array module 1310 are arranged in a sparse lattice form as an M × N lattice, as shown in fig. 4. Through the optical imaging lens of the imaging module 1350, M × N sparse pixel points can be implemented on the screen. In order to display a frame of image with densely arranged pixels, one frame of image needs to be split into a sub-frames displayed in a time division multiplexing mode, namely, light spots corresponding to each independently addressing controlled light source are expanded into the densely arranged a-b light spots through time division multiplexing, and the closely arranged pixels corresponding to the a-b pixels in one frame of image just fill the gaps between the adjacent independently addressable regulated light sources. The switching between sub-frames that can be displayed within a frame time is achieved by the beam scanning/deflection actuator 1330, and finally aM × bN pixels are achieved on the screen. Because the switching time between the sub-frames is far longer than the minimum time that the persistence of vision of human eyes can respond, the integral effect of human eyes splices a plurality of sub-frames into a complete image. The above description divides a frame of image into a × b non-overlapping subframes, where a × b subframes are repeated only once in a frame, and the principle of repeating a × b subframes multiple times is similar, and only the micro-actuator control rate needs to be increased, which is not described here again. It should be noted that, a × b spots corresponding to the same independently controllable light source may also be overlapped or separated in the middle instead of being closely arranged, and the specific scheme may be determined according to the actual imaging requirement.

positions

1, 2, 3, 4 in sequence during a frame time, and each light source constitutes 2 x 2 closely-spaced pixels that do not overlap, forming 2M x 2N pixels as a whole. Fig. 17 shows a de-framing schematic diagram for an example image corresponding to the de-framing method shown in fig. 2.

The video signal source is converted by the decoder 1321 and then transmitted to the light source array driver 1322, and different gray scales are realized by controlling the brightness of the light source at each light spot position, so that the regulation and control of one sub-frame image are completed. When the sub-frame is reached, the light beam scanning/deflecting actuator 1330 moves the light spot corresponding to the array light source to the position corresponding to the sub-frame, and the light source array driver 1322 drives the array light source according to the gray scale corresponding to the sub-frame, so that the gray scale distribution of the corresponding sub-frame is displayed on the image. In the present embodiment, the light source array module 1310 includes three light sources emitting three different colors of light (e.g., G, R, B three colors of light). A color image is realized on the screen by combining the three colors of light, such as G, R, B, through the imaging module 1350 using the light combining module 1340.

Fig. 14 is a schematic block diagram of a display device 1400 according to another embodiment of the present application, in which individually addressable VCSELs are used as array light sources of a light source array module, and a micro-actuator is used as a spot-shifting device to vibrate the light sources. The decoder 1421, VCSEL driver 1422, microactuator driver 1423, and synchronization device 1424 are equivalent to the processor 121, light source driver 122, spot-shift controller 123, and synchronization unit 124, respectively, which constitute the control module 120, as described above.

In the embodiment of fig. 14, the light source array module includes a first light source array module 1410A emitting B (blue) light, a second light source array module 1410B emitting R (red) light, and a third light source array module 1410C emitting G (green) light, which are respectively located at different positions. The three light source array modules have an equal number of light sources. Each light source of the first light source array module 1410A and one light source at a corresponding position in the second light source array module 1410B and three light spots with three colors emitted by one light source at a corresponding position in the third light source array module 1410C can be synthesized into one white light spot by the light combining module 1440. Thus, the three monochromatic light spot arrays emitted by the three light source array modules are finally combined into a mixed color light spot array, such as a white light spot array, by the light combining module 1440.

In this embodiment shown in fig. 14, the micro-actuators as the spot shifting means may also 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, respectively.

The video source is decoded by decoder 1421 and then transmitted to VCSEL driver 1422 and microactuator driver 1423, which are synchronized by synchronization device 1424. The VCSEL of each light

source array module

1410A, 1410B or 1410C is mounted on a two-dimensional micro-actuator or two one-dimensional micro-actuators, and the two one-dimensional micro-actuators control two directions perpendicular to each other, respectively, so that the VCSEL has two-directional vibrations, and the overall scheme is shown in fig. 14. The two dimensions of vibration may be one fast frequency and one slow frequency. The slow frequency direction vibrates in a stepping mode. The micro-actuator may be a linear moving actuator or a deflecting actuator. The laser source may be pulsed to emit light when the microactuator is moved to the desired spot location. For example, the diameter of a single light source of a VCSEL 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, and the whole VCSEL light source array is about 30mm long and about 15mm wide. A resolution of 2k and a refresh rate of 60Hz can be achieved when the vibration frequency in the x-direction is 600Hz and the vibration frequency in the y-direction is 60 Hz. 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 table. In the case of a two-dimensional microactuator, it is optional to use a high-frequency two-dimensional deflection stage to effect deflection in both directions simultaneously. The pulse time sequence of the laser light source can be controlled to match the displacement curve of the micro actuator, so that light spots with equal intervals are projected. For example, when the shift curve is a sine wave, by modulating the pulse timing, an equally spaced output can be achieved, as shown in fig. 11. When the next subframe comes, the micro-actuator moves the light spot corresponding to the array light source to the position corresponding to the subframe, and simultaneously the VCSEL driver 1422 drives the array light source of each light source array module according to the gray scale corresponding to the subframe, and the response time is in ns level, so that the gray scale distribution of the corresponding subframe can be displayed on the image. In one example, the VCSEL driver 1422 drives the light source array modules emitting light of corresponding colors according to the gray scales corresponding to different color components of the sub-frame. The light spots with 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 the multiple subframes obtain densely arranged pixel points through time division multiplexing within one frame time.

The obtained densely arranged pixel points are subjected to RGB three-color light combination by the light combination module 1440, then subjected to optical amplification by the imaging module 1450, and finally projected onto a screen to realize color imaging. RGB three-color light sources need to achieve pixel-level alignment and require temporal shift up-synchronization.

According to the embodiment, the vibration bandwidth of the micro actuator with two dimensions is reduced through the sparse dot matrix light source, the gray scale is realized through the direct drive of the light source, an additional spatial light modulator is not needed, the system is simple, the size is small, the efficiency is high, the resolution ratio is high, and meanwhile, the high dynamic contrast ratio can be realized. Due to the fact that the number of the adopted light sources is large, the speckle effect of the laser can be effectively reduced.

Fig. 15 is a schematic structural diagram of a display device according to still another embodiment of the present application, in which a three-color Micro LED is used as a sparse array light source of a light source array module, and a MEMS scanning mirror or a phase deflection device is used as a spot shifting device to realize beam scanning/spot shifting. The decoder 1521, the LED driver 1522, the scanning device driver 1523 and the synchronization device 1524 are equivalent to the processor 121, the light source driver 122, the spot shift controller 123 and the synchronization unit 124, respectively, which form the control module 120.

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 between them is ensured by the synchronization device 1524. The overall scheme is shown in figure 15. The phase deflector/MEMS mirror 1530, which is a spot shifting device, functions to achieve beam deflection and thus spot shifting. The phase deflector uses the principle of diffraction of light to deflect the main light level by modulating the phase of the light, typical devices such as acousto-optic deflectors and liquid crystals. The MEMS adopts piezoelectric ceramics as a driving source, can realize two-dimensional rapid turnover, and realizes beam deflection by using the reflection principle of light.

The diameter of a single light source of a Micro LED is about 15 microns. In this embodiment, each light source of the LED light source array 1510 is a combined light source composed of three Micro LED light sources emitting R, G, B lights respectively placed together. Fig. 16 shows a schematic diagram of a Micro LED combined light source according to an embodiment of the present application, and three Micro LED light sources emitting R, G, B light respectively are placed close together in a triangular arrangement. The diameter of the combined light source is about 40 microns.

Assuming that each combined light source has a pitch of 400 microns in both the x and y directions, there are 200 light sources in the x direction and 100 light sources in the y direction, the entire array of Micro LED light sources is about 80mm long and about 40mm wide. A resolution of 2k and a refresh rate of 60Hz can be achieved when the scanning frequency in the x-direction is 600Hz and the scanning frequency in the y-direction is 60 Hz. When the acousto-optic deflector is used as a light beam deflection device, because the response time of the acousto-optic deflector is in ns level, the densely arranged pixel point arrangement can be realized without pulse driving of a light source. The response time of the LED driver 1522 is on the order of ns. And driving the array light source according to the gray scale corresponding to the sub-frame, so that the gray scale distribution corresponding to the sub-frame is displayed on the image. The obtained densely arranged pixel points are optically amplified by the imaging module 1540, and finally projected onto a screen to obtain a color image.

According to the embodiment, the sparse dot matrix light source is adopted, the control bandwidth of the light source and the vibration frequency of the micro actuator are reduced, the gray scale is realized by directly driving the light source, and an additional spatial light modulator is not needed. Because the three GRB light sources are combined into a combined light source, a light combination device is not needed, and the synchronous precision of the three-color light sources is not needed to be considered. The system is simple, small in size, high in efficiency and resolution ratio, and high dynamic contrast can be achieved.

The above embodiments are merely examples, and not intended to limit the scope of the present application, and all modifications, equivalents, and flow charts using the contents of the specification and drawings of the present application, or those directly or indirectly applied to other related arts, are included in the scope of the present application.

Claims

1. An imaging method, comprising:

2. The imaging method according to claim 1, wherein the plurality of light sources are arranged in an array having a density less than a density of a pixel distribution of the target image.

3. The imaging method according to claim 1 or 2, characterized in that the method further comprises:

and controlling the brightness of each light source in the plurality of light sources according to the gray scale distribution of each subframe, so that each light spot of the plurality of light sources forms the gray scale display of the corresponding pixel of the subframe at the moment corresponding to the subframe.

4. The imaging method of claim 3, wherein controlling the brightness of each of the plurality of light sources according to the gray scale distribution of each sub-frame comprises:

and at the moment of each sub-frame, the plurality of light sources emit light under the drive of the corresponding drive signals to form light spots corresponding to the sub-frame.

5. The imaging method according to claim 4, further comprising:

and controlling the light source driver to be synchronous with the light spot shifting device according to the plurality of sub-frames, so that when the light spot shifting device moves the light spots of the plurality of light sources to the position corresponding to each sub-frame in 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 the sub-frame.

6. The imaging method according to claim 1, wherein the plurality of light sources of the light source array module is an mxn array, the target image includes X × Y pixels, and the target image includes a number of subframes of a × b, where X ═ M × a and Y ═ N × b.

7. The imaging method of claim 1, wherein the plurality of sub-frames comprises a first sub-frame, wherein one or more pixels of one or more other sub-frames are interleaved between every two adjacent pixels of the first sub-frame.

8. The imaging method according to claim 1, wherein moving the position of the light spot emitted from the light source array module by the light spot shifting means in time series based on the pixel position of each sub-frame comprises:

generating a shift control signal for each sub-frame according to the pixel position of each sub-frame, wherein the shift control signal is used for controlling the light spot shifting device to shift the light spot to reach the position corresponding to the sub-frame;

and shifting the position of the light spot by a light spot shifting device according to the shifting control signal of each sub-frame.

9. The imaging method according to claim 1, wherein the spot shifting means shifts the position of the spot by shifting the positions of the plurality of light sources.

10. The imaging method according to claim 1, wherein the spot shifting means shifts the position of the spot formed by the light beams by deflecting the directions of the light beams emitted from the plurality of light sources.

11. The imaging method according to claim 1, wherein each of the plurality of light sources is a pulse-driven laser light source configured to emit light when the spot shifting device shifts the spot to the target position.

12. The imaging method according to claim 1, wherein each of the plurality of light sources is a pulse-driven laser light source configured to emit light when the spot shifting device shifts the spot to the target position, the imaging method further comprising:

and controlling the time sequence of the pulse for driving the laser light source and the movement of the light spot shifting device so that the laser light source emits light spots with equal intervals along with the movement of the light spot shifting device.

13. The imaging method of claim 1, further comprising:

irradiating the image light onto an object to be measured;

collecting the image light modulated by the object to be detected by a collecting module;

and processing the modulated image light acquired by the acquisition module by an image processing module to obtain the three-dimensional information of the object to be detected.

14. The imaging method according to claim 1,

the light source array module includes a first light source array module including a plurality of first light sources emitting light having a first color, a second light source array module including a plurality of second light sources emitting light having a second color, and a third light source array module including a plurality of third light sources emitting light having a third color;

the light spot shifting device comprises 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;

the step of moving the position of the light spot emitted by the light source array module by the light spot shifting device according to the pixel position of each sub-frame by a time sequence comprises the following steps: and 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 position of each subframe, so that the positions of the light spots of the plurality of first light sources, the plurality of second light sources and the plurality of light source third light sources are in one-to-one correspondence with the positions of the pixels contained in the subframe at the moment corresponding to the subframe.

15. The imaging method of claim 14, wherein each sub-frame of the target image is 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, the independently controlling the brightness of each of the plurality of light sources according to the gray scale distribution of each sub-frame comprising:

independently controlling the brightness of each light source in the plurality of first light sources according to the gray scale distribution of the first subframe component, so that each light spot of the plurality of first light sources forms gray scale display of the first subframe component at the moment corresponding to the subframe;

independently controlling the brightness of each light source in the plurality of second light sources according to the gray scale distribution of the second subframe component, so that each light spot of the plurality of second light sources forms gray scale display of the second subframe component at the moment corresponding to the subframe;

the brightness of each of the plurality of third light sources is independently controlled according to the gray scale distribution of the third sub-frame component so that each light spot of the plurality of third light sources forms a gray scale display of the third sub-frame component at a time corresponding to the sub-frame.

16. The imaging method of claim 15, further comprising:

combining the light spots of the plurality of first light sources, the plurality of second light sources and the plurality of third light sources;

the imaging the light spots emitted by the light source array module and corresponding to the plurality of sub-frames to obtain image light comprises: and imaging the light spots after light combination to obtain image light.

17. The imaging method of claim 1, further comprising:

projecting the image light onto a screen.