Laser projection imaging method and device based on MEMS scanning micromirror

Abstract

The invention relates to a laser projection imaging method and device based on an MEMS scanning micromirror, and the method comprises the steps: determining a first sine drive signal waveform according to a first resonant frequency and a first phase, and determining a second sine drive signal waveform in the same way, a first sine driving signal waveform and a second sine driving signal waveform are sent to an MEMS scanning micromirror, a Lissajous scanning track is generated based on the MEMS scanning micromirror, the first sine driving signal waveform and the second sine driving signal waveform, and a laser modulation time sequence is generated according to a to-be-projected image. Therefore, the laser is controlled to emit a laser source according to the laser modulation time sequence, so that the laser source is reflected to the observation screen through the MEMS scanning micromirror to obtain a projection image. Therefore, the problems that the resolution of the projection technology is limited by physical pixels and a huge optical lens group is needed in the prior art are solved, the projection quality, the real-time performance and the high resolution can be continuously ensured, and the system has the advantages of small size and low power consumption.

Description

Technical Field

[0001] This application relates to the field of micro-electro-mechanical systems (MEMS) device application technology, and in particular to a laser projection imaging method and device based on MEMS scanning micromirrors. Background Technology

[0002] Currently, laser projection imaging mainly consists of digital light processing (DLP) projection chip imaging based on digital micromirror devices (DMD) and pixel panel imaging for liquid crystal displays (LCDs).

[0003] In related technologies, the resolution of DLP projection chips based on digital micromirror arrays (DMDs) is directly determined by the number of pixels in the DMD. For example, 1080P corresponds to 2.07 million pixel units, and the size of the DMD increases as the projection field of view expands.

[0004] However, there are obvious limitations in the relevant technologies: once a DMD has a dead pixel, it will permanently affect the projection quality, and the projection system needs to be equipped with a large optical lens group, which limits the convenience and stability of use. Summary of the Invention

[0005] This application provides a laser projection imaging method and device based on MEMS scanning micromirrors to solve the problems in related technologies where the resolution of projection technology is limited by physical pixels and requires a large optical lens group. It can continuously ensure projection quality, real-time performance and high resolution, and has the advantages of small size and low power consumption.

[0006] The first aspect of this application provides a laser projection imaging method based on a MEMS scanning micromirror, comprising the following steps: Determine the image to be projected, the first resonant frequency, the first phase, the second resonant frequency, and the second phase; The first sinusoidal drive signal waveform is determined based on the first resonant frequency and the first phase, and the second sinusoidal drive signal waveform is determined based on the second resonant frequency and the second phase. The first sinusoidal drive signal waveform and the second sinusoidal drive signal waveform are sent to the MEMS scanning micromirror, so that the MEMS scanning micromirror generates a Lissajous scanning trajectory based on the first sinusoidal drive signal waveform and the second sinusoidal drive signal waveform. Based on the Lissajous scanning trajectory, a laser modulation timing sequence is generated according to the image to be projected, and the laser source is controlled to emit laser light according to the laser modulation timing sequence. The laser source is reflected onto the observation screen through a MEMS scanning micromirror to obtain the projected image.

[0007] Optionally, in some embodiments, generating a laser modulation timing sequence based on the image to be projected, based on the Lissajous scanning trajectory, includes: The image to be projected is mapped from image pixels to trajectory according to the Lissajous scan trajectory to obtain the mapping result; Receive angle information fed back when the MEMS scanning micromirror executes a Lissajous scanning trajectory; The laser modulation timing sequence is generated based on the angle information and mapping results.

[0008] Optionally, in some embodiments, determining the first sinusoidal drive signal waveform based on the first resonant frequency and the first phase, and determining the second sinusoidal drive signal waveform based on the second resonant frequency and the second phase, further includes: The first initial sinusoidal drive signal waveform is determined based on the first resonant frequency and the first phase, and the first initial sinusoidal drive signal waveform is converted into a first sinusoidal analog signal. The first sinusoidal analog signal is then boosted to obtain the first sinusoidal drive signal waveform. The second initial sinusoidal drive signal waveform is determined based on the second resonant frequency and the second phase, and then converted into a second sinusoidal analog signal. The second sinusoidal analog signal is then boosted to obtain the second sinusoidal drive signal waveform.

[0009] Optionally, in some embodiments, sending a first sinusoidal drive signal waveform and a second sinusoidal drive signal waveform to a MEMS scanning micromirror includes: Send the first sinusoidal drive signal waveform to the X-axis drive electrode of the MEMS scanning micromirror; A second sinusoidal drive signal waveform is sent to the Y-axis drive electrode of the MEMS scanning micromirror.

[0010] Optionally, in some embodiments, the relationship between the optical scanning angle and the field of view of the MEMS scanning micromirror is as follows: ; in, The rotation angle of the MEMS scanning micromirror; To observe the horizontal width or vertical height of the image scanned and projected on the screen; This represents the vertical distance between the MEMS scanning micromirror and the observation screen.

[0011] A second aspect of this application provides a laser projection imaging device based on a MEMS scanning micromirror, comprising: The determination module is used to determine the image to be projected, the first resonant frequency, the first phase, the second resonant frequency, and the second phase. The generation module is used to determine a first sinusoidal driving signal waveform based on a first resonant frequency and a first phase, and to determine a second sinusoidal driving signal waveform based on a second resonant frequency and a second phase, and to send the first sinusoidal driving signal waveform and the second sinusoidal driving signal waveform to the MEMS scanning micromirror, so that the MEMS scanning micromirror generates a Lissajous scanning trajectory based on the first sinusoidal driving signal waveform and the second sinusoidal driving signal waveform. The projection module is used to generate a laser modulation timing sequence based on the image to be projected, based on the Lissajous scanning trajectory, and control the laser to emit a laser source according to the laser modulation timing sequence. The laser source is reflected onto the observation screen through the MEMS scanning micromirror to obtain the projected image.

[0012] Optionally, in some embodiments, the projection module is specifically used for: The image to be projected is mapped from image pixels to trajectory according to the Lissajous scan trajectory to obtain the mapping result; Receive angle information fed back when the MEMS scanning micromirror executes a Lissajous scanning trajectory; The laser modulation timing sequence is generated based on the angle information and mapping results.

[0013] Optionally, in some embodiments, the generation module is further configured to: The first initial sinusoidal drive signal waveform is determined based on the first resonant frequency and the first phase, and the first initial sinusoidal drive signal waveform is converted into a first sinusoidal analog signal. The first sinusoidal analog signal is then boosted to obtain the first sinusoidal drive signal waveform. The second initial sinusoidal drive signal waveform is determined based on the second resonant frequency and the second phase, and then converted into a second sinusoidal analog signal. The second sinusoidal analog signal is then boosted to obtain the second sinusoidal drive signal waveform.

[0014] Optionally, in some embodiments, the generation module is specifically used for: Send the first sinusoidal drive signal waveform to the X-axis drive electrode of the MEMS scanning micromirror; A second sinusoidal drive signal waveform is sent to the Y-axis drive electrode of the MEMS scanning micromirror.

[0015] Optionally, in some embodiments, the relationship between the optical scanning angle and the field of view of the MEMS scanning micromirror is as follows: ; in, The rotation angle of the MEMS scanning micromirror; To observe the horizontal width or vertical height of the image scanned and projected on the screen; This represents the vertical distance between the MEMS scanning micromirror and the observation screen.

[0016] A third aspect of this application provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the laser projection imaging method based on MEMS scanning micromirrors as described in the first aspect embodiment.

[0017] A fourth aspect of this application provides a computer-readable storage medium having a computer program stored thereon, which is executed by a processor to implement the laser projection imaging method based on MEMS scanning micromirrors described in the first aspect embodiment.

[0018] Therefore, this application provides a laser projection imaging method based on MEMS scanning micromirrors, and has at least the following innovative points and beneficial effects: (1) The embodiments of this application use MEMS scanning micromirrors for laser projection, which can significantly reduce volume and weight, and achieve high-precision optical scanning and projection at a small scale. It has significant advantages such as small size, low power consumption and high resolution. It can be easily integrated into portable devices such as mobile phones, augmented reality (AR) glasses, and micro projectors to achieve "pocket-level" projection. Its typical application scenarios include, but are not limited to, LiDAR (Light Detection and Ranging), optical coherence tomography (OCT), augmented reality technology (AR), optical communication and other fields.

[0019] (2) The embodiments of this application adopt a laser projection method based on dual-axis resonant Lissajous scanning mode, so that the MEMS scanning micromirror works at a higher frequency, thereby improving the impact and vibration resistance of the embodiments of this application and ensuring the projection quality continuously.

[0020] (3) The embodiments of this application adopt Lissajous trajectory scanning, propose a mapping method from image pixels to trajectory under Lissajous trajectory scanning, use an equal time interval sampling method to achieve accurate pixel positioning, develop a high synchronization MEMS scanning micromirror closed-loop drive control circuit based on field-programmable gate array (FPGA), establish the synchronization relationship between scanning time, image pixels and laser modulation signal, output laser control timing, and ensure real-time performance and resolution.

[0021] (4) The embodiments of this application adopt the MEMS scanning micromirror high projection resolution imaging method. The projection resolution is not rigidly limited by the number of physical pixels. The laser beam scanning trajectory is precisely controlled by the MEMS scanning micromirror to construct the image in the form of "time-sequence pixels". That is, the pixels are defined by the position and brightness modulation of the laser scanning. Theoretically, the physical unit limitation can be broken through by improving the scanning accuracy and scanning frequency, and 4K, 8K or even higher resolution can be easily achieved.

[0022] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0023] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a flowchart of a laser projection imaging method based on a MEMS scanning micromirror provided according to an embodiment of this application; Figure 2 This is a schematic diagram of an optical path scanning based on a MEMS scanning micromirror according to an embodiment of this application; Figure 3 This is a block diagram of a laser projection imaging system based on a MEMS scanning micromirror according to an embodiment of this application; Figure 4 This is a schematic diagram illustrating the simulation effect of a laser projection imaging method based on a MEMS scanning micromirror according to an embodiment of this application; Figure 5 This is a block diagram of a laser projection imaging device based on a MEMS scanning micromirror according to an embodiment of this application; Figure 6 This is a schematic diagram of the structure of an electronic device according to an embodiment of this application. Detailed Implementation

[0024] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0025] The following description, with reference to the accompanying drawings, illustrates a laser projection imaging method and apparatus based on a MEMS scanning micromirror, according to embodiments of this application. Addressing the issues of resolution limitations due to physical pixels and the need for large optical lens groups in related technologies mentioned in the background, this application proposes a laser projection imaging method based on a MEMS scanning micromirror. This method sends a first sinusoidal driving signal waveform and a second sinusoidal driving signal waveform to the MEMS scanning micromirror, and generates a Lissajous scanning trajectory based on the MEMS scanning micromirror, the first sinusoidal driving signal waveform, and the second sinusoidal driving signal waveform. A laser modulation timing sequence is generated according to the image to be projected, and the laser source is controlled to emit a laser source according to the laser modulation timing sequence. The laser source is then reflected by the MEMS scanning micromirror onto an observation screen to obtain a projected image. This solves the problems of resolution limitations due to physical pixels and the need for large optical lens groups in related technologies, ensuring consistent projection quality, real-time performance, and high resolution, while also offering advantages such as small size and low power consumption.

[0026] Specifically, Figure 1 This is a flowchart of a laser projection imaging method based on a MEMS scanning micromirror, provided as an embodiment of this application.

[0027] like Figure 1 As shown, the laser projection imaging method based on MEMS scanning micromirrors includes the following steps: In step S101, the image to be projected, the first resonant frequency, the first phase, the second resonant frequency, and the second phase are determined.

[0028] The image to be projected is an image projected onto a target carrier (such as an observation screen) via laser projection and contains preset graphics, text, video frames, or data visualization content; the first resonant frequency and the second resonant frequency can both be resonant frequencies preset by the user, which can be resonant frequencies obtained through a limited number of experiments or resonant frequencies obtained through a limited number of computer simulations; the first phase and the second phase can both be phases preset by the user, which can be phases obtained through a limited number of experiments or phases obtained through a limited number of computer simulations, and are not specifically limited here.

[0029] In step S102, a first sinusoidal drive signal waveform is determined based on the first resonant frequency and the first phase, and a second sinusoidal drive signal waveform is determined based on the second resonant frequency and the second phase. The first and second sinusoidal drive signal waveforms are then sent to the MEMS scanning micromirror, so that the MEMS scanning micromirror generates a Lissajous scanning trajectory based on the first and second sinusoidal drive signal waveforms.

[0030] In some embodiments, determining a first sinusoidal driving signal waveform based on a first resonant frequency and a first phase, and determining a second sinusoidal driving signal waveform based on a second resonant frequency and a second phase, further includes: determining a first initial sinusoidal driving signal waveform based on the first resonant frequency and the first phase, converting the first initial sinusoidal driving signal waveform into a first sinusoidal analog signal, and performing a boost operation on the first sinusoidal analog signal to obtain the first sinusoidal driving signal waveform; determining a second initial sinusoidal driving signal waveform based on the second resonant frequency and the second phase, converting the second initial sinusoidal driving signal waveform into a second sinusoidal analog signal, and performing a boost operation on the second sinusoidal analog signal to obtain the second sinusoidal driving signal waveform.

[0031] In some embodiments, sending a first sinusoidal drive signal waveform and a second sinusoidal drive signal waveform to the MEMS scanning micromirror includes: sending the first sinusoidal drive signal waveform to the X-axis drive electrode of the MEMS scanning micromirror; and sending the second sinusoidal drive signal waveform to the Y-axis drive electrode of the MEMS scanning micromirror.

[0032] The first sinusoidal drive signal waveform is a sinusoidal drive electrical signal with a first resonant frequency and a first phase, which drives the X-axis drive electrode of the MEMS scanning micromirror to achieve scanning motion in the X-axis direction; the second sinusoidal drive signal waveform is a sinusoidal drive electrical signal with a second resonant frequency and a second phase, which drives the Y-axis drive electrode of the MEMS scanning micromirror to achieve scanning motion in the Y-axis direction; the Lissajous scan trajectory refers to the periodic closed scan trajectory formed by the MEMS scanning micromirror under the combined action of the X-axis and Y-axis sinusoidal drive signals.

[0033] Specifically, in this embodiment of the application, a sinusoidal drive signal waveform (i.e., a first initial sinusoidal drive signal waveform) of the X-axis of the MEMS scanning micromirror can be designed inside the FPGA. The first initial sinusoidal drive signal waveform is converted into an analog signal (i.e., a first sinusoidal analog signal) through a digital-to-analog converter circuit module (DA). The first sinusoidal analog signal is then converted into a first sinusoidal drive signal waveform through a boost module. Similarly, in this embodiment of the application, a sinusoidal drive signal waveform (i.e., a second initial sinusoidal drive signal waveform) of the Y-axis of the MEMS scanning micromirror can be designed inside the FPGA. The second initial sinusoidal drive signal waveform is converted into an analog signal (i.e., a second sinusoidal analog signal) through a DA circuit module. The second sinusoidal analog signal is then converted into a second sinusoidal drive signal waveform through a boost module.

[0034] Furthermore, after determining the first sinusoidal drive signal waveform and the second sinusoidal drive signal waveform, embodiments of this application can connect the boost module to the X-axis resonant drive electrode of the MEMS scanning micromirror, thereby sending the first sinusoidal drive signal waveform to the X-axis drive electrode of the MEMS scanning micromirror; similarly, embodiments of this application can also connect the boost module to the Y-axis resonant drive electrode of the MEMS scanning micromirror, thereby sending the second sinusoidal drive signal waveform to the Y-axis drive electrode of the MEMS scanning micromirror.

[0035] Furthermore, by combining the deflection angle feedback information from the MEMS scanning micromirror to the FPGA, the embodiments of this application can further derive its transfer function model, measure the relationship between its input voltage and deflection angle, design the state variables of time, voltage and scanning angle, and establish a closed-loop control model to realize high-precision Lissajous scanning control of the MEMS scanning micromirror and generate Lissajous scanning trajectory.

[0036] In step S103, a laser modulation timing sequence is generated based on the Lissajous scanning trajectory and the image to be projected. The laser source is controlled to emit a laser source according to the laser modulation timing sequence. The laser source is reflected onto the observation screen through the MEMS scanning micromirror to obtain the projected image.

[0037] In some embodiments, generating a laser modulation timing sequence based on the image to be projected, according to the Lissajous scanning trajectory, includes: mapping the image pixels to the trajectory of the image to be projected according to the Lissajous scanning trajectory to obtain a mapping result; receiving angle information fed back when the MEMS scanning micromirror executes the Lissajous scanning trajectory; and generating a laser modulation timing sequence based on the angle information and the mapping result.

[0038] Among them, laser modulation timing is a timing signal used to control the intensity and timing of laser light emission; laser source is a monochromatic or red-green-blue laser (RGB) used for projection imaging; observation screen is a carrier used to present the projected image; projected image refers to the image of the target to be projected formed point by point and line by line on the observation screen; image pixel refers to the basic unit that makes up the image in the image to be projected; trajectory mapping refers to the process of establishing a correspondence between image pixels and their positions on the Lissajous scanning trajectory; mapping result refers to the correspondence data between image pixels and the scanning trajectory positions; angle information refers to the rotation angle data fed back in real time when the MEMS scanning micromirror performs scanning.

[0039] Specifically, after generating the Lissajous scanning trajectory, this embodiment of the application can map the image or video to be projected (i.e., the image to be projected) to the trajectory according to the actual Lissajous scanning trajectory of the MEMS scanning micromirror, and use equal time interval sampling to achieve precise pixel positioning; and establish a synchronous correspondence between scanning time, image pixels and laser modulation signal on the FPGA, output laser modulation timing, and realize that the laser source is reflected onto the screen through the MEMS scanning micromirror to draw the projected image point by point and line by line. The laser source can be monochrome or RGB.

[0040] Furthermore, the laser is reflected onto the image plane by a MEMS scanning micromirror. The two-dimensional MEMS scanning micromirror vibrates along the X and Y axes to achieve two-dimensional laser scanning. The high resonant frequency and large scanning angle of the MEMS scanning micromirror are used to scan the laser point to the corresponding position on the screen, and the laser intensity is adjusted by the modulation signal to form a complete image.

[0041] Therefore, based on the high-speed parallel processing capability of FPGA, this embodiment uses FPGA as the core controller in the laser image modulation process to perform high-speed intensity modulation of the laser to control its light output state. Specifically, the FPGA outputs the Boolean value of the corresponding image pixel at each sampling moment according to the timing information of the image data to be projected and the Lissajous scanning trajectory, and controls the driving current of the laser through transistor-transistor logic (TTL) signals, thereby realizing dynamic adjustment of laser intensity. At the same time, by strictly synchronizing with the scanning time of the MEMS scanning micromirror, that is, at the instant when the light spot moves to a certain coordinate position on the image plane, the FPGA outputs the light intensity modulation information corresponding to that position, completes point-to-point image reconstruction, realizes sub-microsecond response speed, and ensures accurate restoration of image details and continuity of dynamic display effect.

[0042] Furthermore, to enable those skilled in the art to better understand the laser projection imaging method based on MEMS scanning micromirrors in the embodiments of this application, the following is combined with... Figures 2 to 4 Specific embodiments are described in detail below.

[0043] To overcome the shortcomings of related technologies, this application proposes a laser projection imaging method based on a MEMS scanning micromirror. The core of this application lies in utilizing a high-frequency resonant MEMS scanning micromirror to rapidly project a laser spot onto a screen or imaging surface along a pre-set scanning trajectory, thereby achieving a preset scanning mode and generating a complete image.

[0044] Specifically, this application embodiment can employ a dual-axis resonant Lissajous scanning laser projection imaging method. The MEMS scanning micromirror is in a dual-axis resonant state, resulting in a fast scanning speed and improved shock and vibration resistance. When mapping image pixels to the trajectory under the Lissajous scanning path, this application embodiment can use an equal-time-interval sampling method to achieve precise pixel positioning. A highly synchronous MEMS scanning micromirror closed-loop drive control circuit is developed based on an FPGA, simultaneously establishing a synchronization relationship between scanning time, image pixels, and laser modulation signals, outputting laser control timing to ensure real-time performance and resolution. The scanning optical path of the MEMS scanning micromirror is as follows: Figure 2 As shown; Figure 2 This is a schematic diagram of an optical path scanning based on a MEMS scanning micromirror, provided as an embodiment of this application.

[0045] Furthermore, in this embodiment of the application, accurately displaying a frame of image in Lissajous scanning mode requires acquiring image pixel information of the scanning trajectory within the motion time of a certain pixel, and accurately applying that image pixel information to generate the modulation timing of the laser, ultimately achieving the display of the entire image. Therefore, this embodiment of the application needs to establish a synchronous correspondence between time, pixels, and the laser modulation signal. In addition, establishing the time-pixel correspondence first requires studying the reflection position of the laser spot at a specific moment and measuring the distance between the MEMS scanning micromirror and the observation screen. When the MEMS scanning micromirror rotates by an angle of When the optical scanning angle is related to the field of view, the relationship is as follows:

[0046] in, The rotation angle of the MEMS scanning micromirror; To observe the horizontal width or vertical height of the image scanned and projected on the screen; This represents the vertical distance between the MEMS scanning micromirror and the observation screen.

[0047] The vibration equations for the two axes of the scanning mirror are as follows:

[0048] in, It refers to the vibrational displacement of the MEMS scanning micromirror in the x-axis direction; It refers to the vibration amplitude of the MEMS scanning micromirror in the x-axis direction; It refers to the vibration frequency of the MEMS scanning micromirror in the x-axis direction; It refers to the initial phase of the vibration of the MEMS scanning micromirror in the x-axis direction; It refers to time; This refers to the amplitude of vibration; It refers to the x-axis direction of the vibration of the MEMS scanning micromirror; It refers to the vibrational displacement of the MEMS scanning micromirror in the y-axis direction; It refers to the vibration amplitude of the MEMS scanning micromirror in the y-axis direction; It refers to the vibration frequency of the MEMS scanning micromirror in the y-axis direction; It refers to the initial phase of the vibration of the MEMS scanning micromirror in the y-axis direction; It refers to the y-axis direction of the vibration of the MEMS scanning micromirror.

[0049] The light spot is reflected by the MEMS scanning micromirror and its position on the observation screen is as follows:

[0050] in, This refers to the position of the light spot along the x-axis of the observation screen; It refers to the vibration amplitude of the MEMS scanning micromirror in the x-axis direction; It refers to the vibration frequency of the MEMS scanning micromirror in the x-axis direction; This refers to the initial phase of the light spot along the x-axis. It refers to time; This refers to the amplitude of vibration; It refers to the x-axis direction of the vibration of the MEMS scanning micromirror; This refers to the position of the light spot along the y-axis of the observation screen; It refers to the vibration amplitude of the MEMS scanning micromirror in the y-axis direction; It refers to the vibration frequency of the MEMS scanning micromirror in the y-axis direction; This refers to the initial phase of the light spot along the y-axis. It refers to the y-axis direction of the vibration of the MEMS scanning micromirror.

[0051] It should be understood that the above formula is By constantly scanning the coordinates of the light spot on the observation screen, the corresponding pixel in the image can be obtained using the coordinates of that point, thus obtaining the time-pixel correspondence and consequently the laser modulation timing corresponding to the time-pixel.

[0052] Furthermore, in Lissajous scanning mode, because both axes are undergoing sinusoidal motion, the spatial displacement velocity of the scanning spot is not constant within each equal time interval, resulting in varying scan lengths. In equal-interval sampling, the pixel coordinates of the sampled points within each time interval may not be equally spaced, thus requiring the acquisition of pixel information corresponding to the pixel coordinates based on the actual motion trajectory. Moreover, in actual image reconstruction, this non-uniform sampling causes two main problems: first, multiple sampling points may correspond to the same pixel location in the image, leading to duplicate sampling; second, some pixel regions may be sparsely sampled or located at the edge of the trajectory, potentially not covered by the sampling spot, resulting in pixel mismatch. However, despite the occurrence of multiple point duplications or pixel mismatches, as long as the scanning frequency is high enough and the scanning trajectory is dense enough, the errors caused by non-uniform sampling can be effectively compensated for, ensuring correct reading and sampling.

[0053] Figure 3 This is a block diagram illustrating a laser projection imaging system based on a MEMS scanning micromirror, as provided in one embodiment of this application.

[0054] like Figure 3 As shown, the laser projection imaging system based on a MEMS scanning micromirror includes: an FPGA circuit module 301, a DA circuit module 302, a boost circuit module 303, a MEMS scanning micromirror 304, and a laser circuit module 305. Specifically, the FPGA circuit module 301 generates two sinusoidal signals, which are converted into sinusoidal analog signals by the DA circuit module 302, and the boost circuit module 303 increases the amplitude voltage of the sinusoidal drive signals. These two drive signals are simultaneously connected to the X-axis and Y-axis drive electrodes, respectively, and the deflection angle feedback information of the MEMS scanning micromirror 304 is transmitted back to the FPGA circuit module 301. For the MEMS scanning micromirror 304 used, its transfer function model is derived, the relationship between its input voltage and deflection angle is measured, the state variables of time, voltage, and scanning angle are designed, a closed-loop control model is established, and a control circuit is designed and developed in the FPGA circuit module 301 based on the model to achieve high-precision Lissajous scanning control of the MEMS scanning micromirror 304. In Lissajous scanning mode, the image pixel information of the scanning trajectory within a certain pixel movement time on the specific image to be projected is calculated. A synchronous correspondence is established between the scanning time, image pixels, and the modulation signal of the laser circuit module 305. The laser modulation timing sequence is output, enabling the laser source (monochrome or RGB) to be reflected onto the screen through the MEMS scanning micromirror 304, thus drawing the projected image point by point and line by line. The simulation effect diagram of the laser projection imaging method based on the MEMS scanning micromirror can be seen as follows: Figure 4 As shown; where, Figure 4 (a) is the image to be projected; Figure 4(b) is a schematic diagram of the Lissajous trajectory with equal intervals; Figure 4 (c) is a schematic diagram of the projected image.

[0055] The laser projection imaging method based on a MEMS scanning micromirror proposed in this application involves sending a first sinusoidal driving signal waveform and a second sinusoidal driving signal waveform to the MEMS scanning micromirror. A Lissajous scanning trajectory is generated based on the MEMS scanning micromirror, the first sinusoidal driving signal waveform, and the second sinusoidal driving signal waveform. A laser modulation timing sequence is generated according to the image to be projected, and the laser source is controlled to emit a laser source according to the laser modulation timing sequence. The laser source is then reflected by the MEMS scanning micromirror onto the observation screen to obtain the projected image. This solves the problems of resolution limitations due to physical pixels and the need for large optical lens groups in related technologies. It can consistently guarantee projection quality, real-time performance, and high resolution, and also has the advantages of small size and low power consumption.

[0056] Next, referring to the accompanying drawings, a laser projection imaging device based on a MEMS scanning micromirror, according to an embodiment of this application, is described.

[0057] Figure 5 This is a block diagram of a laser projection imaging device based on a MEMS scanning micromirror according to an embodiment of this application.

[0058] like Figure 5 As shown, the laser projection imaging device 10 based on MEMS scanning micromirrors includes: a determination module 100, a generation module 200, and a projection module 300.

[0059] The module 100 is used to determine the image to be projected, the first resonant frequency, the first phase, the second resonant frequency, and the second phase. The generation module 200 is used to determine the first sinusoidal driving signal waveform based on the first resonant frequency and the first phase, and to determine the second sinusoidal driving signal waveform based on the second resonant frequency and the second phase. The generation module 200 sends the first sinusoidal driving signal waveform and the second sinusoidal driving signal waveform to the MEMS scanning micromirror, so that the MEMS scanning micromirror generates a Lissajous scanning trajectory based on the first sinusoidal driving signal waveform and the second sinusoidal driving signal waveform. The projection module 300 is used to generate a laser modulation timing sequence based on the Lissajous scanning trajectory and the image to be projected, and to control the laser to emit a laser source according to the laser modulation timing sequence. The laser source is reflected onto the observation screen by the MEMS scanning micromirror to obtain the projected image.

[0060] Optionally, in some embodiments, the projection module 300 is specifically used for: mapping the image to be projected to a trajectory according to a Lissajous scanning trajectory to obtain a mapping result; receiving angle information fed back when the MEMS scanning micromirror performs a Lissajous scanning trajectory; and generating a laser modulation timing sequence based on the angle information and the mapping result.

[0061] Optionally, in some embodiments, the generation module 200 is further configured to: determine a first initial sinusoidal driving signal waveform based on a first resonant frequency and a first phase, convert the first initial sinusoidal driving signal waveform into a first sinusoidal analog signal, and perform a boost operation on the first sinusoidal analog signal to obtain a first sinusoidal driving signal waveform; determine a second initial sinusoidal driving signal waveform based on a second resonant frequency and a second phase, convert the second initial sinusoidal driving signal waveform into a second sinusoidal analog signal, and perform a boost operation on the second sinusoidal analog signal to obtain a second sinusoidal driving signal waveform.

[0062] Optionally, in some embodiments, the generation module 200 is specifically used to: send a first sinusoidal driving signal waveform to the X-axis driving electrode of the MEMS scanning micromirror; and send a second sinusoidal driving signal waveform to the Y-axis driving electrode of the MEMS scanning micromirror.

[0063] Optionally, in some embodiments, the relationship between the optical scanning angle and the field of view of the MEMS scanning micromirror is as follows: ; in, The rotation angle of the MEMS scanning micromirror; To observe the horizontal width or vertical height of the image scanned and projected on the screen; This represents the vertical distance between the MEMS scanning micromirror and the observation screen.

[0064] It should be noted that the foregoing explanation of the embodiment of the laser projection imaging method based on MEMS scanning micromirrors also applies to the laser projection imaging device based on MEMS scanning micromirrors in this embodiment, and will not be repeated here.

[0065] The laser projection imaging device based on a MEMS scanning micromirror proposed in this application sends a first sinusoidal driving signal waveform and a second sinusoidal driving signal waveform to the MEMS scanning micromirror. A Lissajous scanning trajectory is generated based on the MEMS scanning micromirror, the first sinusoidal driving signal waveform, and the second sinusoidal driving signal waveform. A laser modulation timing sequence is generated according to the image to be projected, and the laser source is controlled to emit a laser source according to the laser modulation timing sequence. The laser source is reflected by the MEMS scanning micromirror onto the observation screen to obtain a projected image. This solves the problems of resolution limitations due to physical pixels and the need for large optical lens groups in related technologies. It can continuously guarantee projection quality, real-time performance, and high resolution, and has the advantages of small size and low power consumption.

[0066] Figure 6 A schematic diagram of the structure of an electronic device provided in an embodiment of this application. The electronic device may include: The memory 601, the processor 602, and the computer program stored on the memory 601 and capable of running on the processor 602.

[0067] When the processor 602 executes the program, it implements the laser projection imaging method based on MEMS scanning micromirrors provided in the above embodiments.

[0068] Furthermore, electronic devices also include: Communication interface 603 is used for communication between memory 601 and processor 602.

[0069] The memory 601 is used to store computer programs that can run on the processor 602.

[0070] The memory 601 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0071] If the memory 601, processor 602, and communication interface 603 are implemented independently, then the communication interface 603, memory 601, and processor 602 can be interconnected via a bus to complete communication between them. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of representation, Figure 6 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0072] Optionally, in a specific implementation, if the memory 601, processor 602, and communication interface 603 are integrated on a single chip, then the memory 601, processor 602, and communication interface 603 can communicate with each other through an internal interface.

[0073] The processor 602 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application.

[0074] This application also provides a computer-readable storage medium having a computer program stored thereon, which is implemented when executed by a processor. Figure 1 The embodiment describes a laser projection imaging method based on MEMS scanning micromirrors.

[0075] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0076] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0077] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more N executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0078] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0079] It should be understood that the various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0080] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0081] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0082] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. A laser projection imaging method based on MEMS scanning micromirror, characterized in that, The method comprises the steps of: determining an image to be projected, a first resonant frequency, a first phase, a second resonant frequency, and a second phase; determining a first sinusoidal driving signal waveform according to the first resonant frequency and the first phase, and a second sinusoidal driving signal waveform according to the second resonant frequency and the second phase, and sending the first sinusoidal driving signal waveform and the second sinusoidal driving signal waveform to the MEMS scanning micromirror, so that the MEMS scanning micromirror generates a Lissajous scanning trajectory based on the first sinusoidal driving signal waveform and the second sinusoidal driving signal waveform; based on the Lissajous scanning trajectory, generating laser modulation timing according to the image to be projected, and controlling a laser to emit a laser source according to the laser modulation timing, and the laser source is reflected onto an observation screen by the MEMS scanning micromirror to obtain a projected image.

2. The method of claim 1, wherein, The step of generating laser modulation timing according to the image to be projected based on the Lissajous scanning trajectory comprises the steps of: performing image pixel-to-trajectory mapping on the image to be projected according to the Lissajous scanning trajectory to obtain a mapping result; receiving angle information fed back when the MEMS scanning micromirror executes the Lissajous scanning trajectory; generating the laser modulation timing according to the angle information and the mapping result.

3. The method of claim 1, wherein, The step of determining a first sinusoidal driving signal waveform according to the first resonant frequency and the first phase, and a second sinusoidal driving signal waveform according to the second resonant frequency and the second phase further comprises the steps of: determining a first initial sinusoidal driving signal waveform according to the first resonant frequency and the first phase, converting the first initial sinusoidal driving signal waveform into a first sinusoidal analog signal, and performing a voltage boosting operation on the first sinusoidal analog signal to obtain the first sinusoidal driving signal waveform; determining a second initial sinusoidal driving signal waveform according to the second resonant frequency and the second phase, converting the second initial sinusoidal driving signal waveform into a second sinusoidal analog signal, and performing a voltage boosting operation on the second sinusoidal analog signal to obtain the second sinusoidal driving signal waveform.

4. The method according to claim 1 or 3, characterized in that, The step of sending the first sinusoidal driving signal waveform and the second sinusoidal driving signal waveform to the MEMS scanning micromirror comprises the steps of: sending the first sinusoidal driving signal waveform to an X-axis driving electrode of the MEMS scanning micromirror; sending the second sinusoidal driving signal waveform to a Y-axis driving electrode of the MEMS scanning micromirror.

5. The method of claim 1, wherein, The relationship between the optical scanning angle of the MEMS scanning micromirror and the field of view range is: ； wherein, is the rotation angle of the MEMS scanning micromirror; is the horizontal width or vertical height of the image scanned and projected on the viewing screen; is the vertical distance between the MEMS scanning micromirror and the viewing screen.

6. A laser projection imaging device based on a MEMS scanning micromirror, comprising: a determining module configured to determine an image to be projected, a first resonant frequency, a first phase, a second resonant frequency, and a second phase; a determining module configured to determine an image to be projected, a first resonant frequency, a first phase, a second resonant frequency, and a second phase; generating a first sinusoidal driving signal waveform according to the first resonant frequency and the first phase, and a second sinusoidal driving signal waveform according to the second resonant frequency and the second phase, and sending the first sinusoidal driving signal waveform and the second sinusoidal driving signal waveform to the MEMS scanning micromirror, so that the MEMS scanning micromirror generates a Lissajous scanning trajectory based on the first sinusoidal driving signal waveform and the second sinusoidal driving signal waveform; projecting, based on the Lissajous scanning trajectory, a laser modulation timing according to the image to be projected, and controlling a laser to emit a laser source according to the laser modulation timing, so that the laser source is reflected by the MEMS scanning micromirror onto an observation screen to obtain a projected image.

7. The apparatus of claim 6, wherein, The projection module is specifically configured to: perform image pixel-to-trajectory mapping on the image to be projected according to the Lissajous scanning trajectory to obtain a mapping result; receive angle information fed back by the MEMS scanning micromirror when the MEMS scanning micromirror executes the Lissajous scanning trajectory; generate the laser modulation timing according to the angle information and the mapping result.

8. The apparatus of claim 6, wherein, The generation module is further configured to: determine a first initial sinusoidal driving signal waveform according to the first resonant frequency and the first phase, convert the first initial sinusoidal driving signal waveform into a first sinusoidal analog signal, and perform a voltage boosting operation on the first sinusoidal analog signal to obtain the first sinusoidal driving signal waveform; determine a second initial sinusoidal driving signal waveform according to the second resonant frequency and the second phase, convert the second initial sinusoidal driving signal waveform into a second sinusoidal analog signal, and perform a voltage boosting operation on the second sinusoidal analog signal to obtain the second sinusoidal driving signal waveform.

9. An electronic device, comprising: comprise: a memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the program to implement the MEMS scanning micromirror-based laser projection imaging method according to any one of claims 1-5.

10. A computer-readable storage medium storing a computer program, the computer program comprising instructions that, when executed by a computer, cause the computer to perform the method of any one of claims 1 to 9. The program is executed by the processor to implement the MEMS scanning micromirror-based laser projection imaging method according to any one of claims 1-5.

Images