A delay adjustment method and projection display device

Abstract

The present invention discloses a delay adjustment method and projection display device. The method employs a QPD (Quantity Detection Device) to perform feedback detection on the light output by a detection light source, inserts the detection image information into the image to be projected, and generates an image to be projected that carries the detection light information. The position of the detection image on the QPD is used to determine whether the delays between the light source and the fiber scanner are aligned, thereby ensuring the delay alignment between the image light source and the fiber scanner to achieve normal projection display. Because the QPD sensor and corresponding signal processing are essential for feedback detection, the feedback detection device in the embodiments of the present invention is easier to integrate with the projection system at the circuit level. Chipping the feedback detection device reduces system complexity, particularly advantageous for use in projection systems with specific volume requirements.

Description

Technical Field

[0001] The present invention relates to the field of projection display, and in particular to a delay adjustment method and a projection display device. Background Art

[0002] The imaging principle of fiber scanning display (FSD) technology is to use a fiber scanner to drive a scanning optical fiber to move along a predetermined two-dimensional scanning trajectory and modulate the light output of a light source, that is, to modulate the light corresponding to each pixel of the projected image to be displayed. Then, the light corresponding to each pixel of the projected image is projected one by one onto the projection surface through the scanning optical fiber, thus forming a projected image.

[0003] The projected image can only be displayed normally when the delays of the light source and the fiber scanner are aligned. If the delays of the light source and the fiber scanner are misaligned, pixel misalignment or even display area misalignment will occur. Therefore, how to achieve delay alignment between the light source and the fiber scanner is a technical problem that must be solved for fiber optic scanning display. Summary of the Invention

[0004] The object of the present invention is to provide a delay adjustment method and a projection display device for achieving delay alignment between a light source and a fiber scanner.

[0005] To achieve the above-mentioned object, a first aspect of an embodiment of the present invention provides a delay adjustment method, which is applied to a projection display device. The projection display device includes a light source, a fiber scanner, a spectrometer, and a four-quadrant photodiode (QPD). The light source includes an image light source and a detection light source. The method includes:

[0006] Acquire an image to be projected, and insert detection image information into the image to be projected to generate an image to be projected with detection light information;

[0007] Controlling the light source to output light corresponding to the image to be projected with detection light information, and adjusting the delay between the light source and the fiber scanner; wherein the light emitted by the image light source and the detection light source is coupled into the fiber scanner, and after the light emitted by the fiber scanner is split by the spectrometer, the light emitted by the detection light source is projected onto the QPD to form a detection image, and the light emitted by the image light source is used to form a projection image;

[0008] During the process of adjusting the delay, the QPD is controlled to collect the light intensity of the detection image in the four quadrants of the QPD, and the actual position of the detection image on the QPD is determined based on the light intensity in the four quadrants of the QPD. The delay adjustment is stopped until the actual position of the detection image on the QPD coincides with the target position.

[0009] Optionally, the delay includes horizontal delay and vertical delay; the horizontal delay refers to the delay between the first pixel and the starting point of the scanning trajectory of the row of images when displaying a row of images; the vertical delay refers to the delay between the first row of pixels and the first row of scanning trajectory of the frame of images when displaying a frame of images.

[0010] Optionally, the detection image is a non-uniform grayscale image, so that during the process of adjusting the delay, the illumination intensity in the four quadrants changes non-uniformly; the method includes:

[0011] During the process of adjusting the delay, the variation of the light intensity in the four quadrants is calculated, the adjustment direction of the delay is determined according to the variation, and the delay is continuously adjusted according to the adjustment direction of the delay.

[0012] Optionally, the detected image includes an image for detecting horizontal delay and an image for detecting vertical delay; and adjusting the delay between the light source and the optical fiber scanner includes:

[0013] Adjusting the delay according to a delay adjustment method corresponding to the target position of the image for detecting the horizontal delay until the actual position of the image for detecting the horizontal delay is horizontally coincident with the target position of the image for detecting the horizontal delay, and stopping adjusting the horizontal delay;

[0014] The delay is adjusted according to the delay adjustment method corresponding to the target position of the image for detecting vertical delay, until the actual position of the image for detecting vertical delay vertically coincides with the target position of the image for detecting vertical delay, and the vertical delay adjustment is stopped.

[0015] Optionally, the four quadrants of the QPD are distributed in a field shape, with quadrants 1 and 2 located at the top, quadrants 3 and 4 located at the bottom, and quadrants 1 and 3 located on the left, and quadrants 2 and 4 located on the right; the target position of the image for detecting horizontal delay is located at the rightmost side of quadrant 1 or quadrant 3, or at the leftmost side of quadrant 2 or quadrant 4; and the delay is adjusted according to a delay adjustment method corresponding to the target position of the image for detecting horizontal delay until the actual position of the image for detecting horizontal delay horizontally coincides with the target position of the image for detecting horizontal delay, including:

[0016] Adjusting the vertical delay and the horizontal delay until the image for detecting the horizontal delay is located in quadrants 1 and 2, and the light intensity values ​​of quadrants 1 and 2 are not 0, or until the image for detecting the horizontal delay is located in quadrants 3 and 4, and the light intensity values ​​of quadrants 3 and 4 are not 0;

[0017] If the target position of the image for detecting horizontal delay is located at the rightmost side of quadrant 1 or quadrant 3, each time the horizontal delay is adjusted, it is determined whether the light intensity of quadrant 1 or quadrant 3 reaches a maximum value, and whether the corresponding light intensity of quadrant 2 or quadrant 4 is 0; if so, it is determined that the actual position of the image for detecting horizontal delay on the QPD horizontally coincides with the target position of the image for detecting horizontal delay;

[0018] If the target position of the image for detecting horizontal delay is located at the leftmost side of quadrant 2 or quadrant 4, each time the horizontal delay is adjusted, it is determined whether the light intensity of quadrant 1 or quadrant 3 is 0, and whether the corresponding light intensity of quadrant 2 or quadrant 4 reaches the maximum value; if so, it is determined that the actual position of the image for detecting horizontal delay on the QPD coincides horizontally with the target position of the image for detecting horizontal delay.

[0019] Optionally, the grayscale of the image for detecting horizontal delay gradually increases or decreases from left to right; the method further includes:

[0020] During the process of adjusting the horizontal delay, the QPD is controlled to collect and calculate the change in light intensity of the image detecting the horizontal delay in quadrant 1 or quadrant 2, or the change in light intensity of quadrant 3 or quadrant 4 is calculated, and whether the adjustment direction of the horizontal delay is correct is determined based on the change in light intensity and a pre-set judgment rule; if correct, continue to adjust the horizontal delay; if incorrect, adjust the horizontal delay in the opposite direction.

[0021] Optionally, the determination rule refers to:

[0022] If the horizontal target position is located at the rightmost side of quadrant 1 or quadrant 3, and the grayscale of the image for detecting the horizontal delay gradually increases from left to right, then during the process of adjusting the horizontal delay, if the change in the light intensity of quadrant 1 or quadrant 3 gradually increases, it is determined that the adjustment direction is correct;

[0023] If the horizontal target position is located at the rightmost side of quadrant 1 or quadrant 3, and the grayscale of the image for detecting the horizontal delay gradually decreases from left to right, then during the process of adjusting the horizontal delay, if the change in the light intensity of quadrant 1 or quadrant 3 gradually decreases, it is determined that the adjustment direction is correct;

[0024] If the horizontal target position is located at the leftmost side of quadrant 2 or quadrant 4, and the grayscale of the image for detecting the horizontal delay gradually increases from left to right, then during the process of adjusting the horizontal delay, if the change in the light intensity of quadrant 2 or quadrant 4 gradually decreases, it is determined that the adjustment direction is correct;

[0025] If the horizontal target position is located at the leftmost side of the 2nd or 4th quadrant, and the grayscale of the image detecting the horizontal delay gradually decreases from left to right, then during the process of adjusting the horizontal delay, if the change in the light intensity of the 2nd or 4th quadrant gradually increases, it is determined that the adjustment direction is correct.

[0026] Optionally, the four quadrants of the QPD are distributed in a field shape, with quadrants 1 and 2 located at the top, quadrants 3 and 4 located at the bottom, and quadrants 1 and 3 located on the left, and quadrants 2 and 4 located on the right; the target position of the image for detecting vertical delay is located at the bottom of quadrant 1 or quadrant 2, or at the top of quadrant 3 or quadrant 4; and the delay is adjusted according to a delay adjustment method corresponding to the target position of the image for detecting vertical delay until the actual position of the image for detecting vertical delay vertically coincides with the target position of the image for detecting vertical delay, including:

[0027] Adjusting the horizontal delay until the image for detecting the vertical delay is located in quadrants 2 and 4, and the illumination intensities of the quadrants 2 and 4 are not zero, or until the image for detecting the vertical delay is located in quadrants 1 and 3, and the illumination intensities of the quadrants 1 and 3 are not zero;

[0028] If the target position of the image for detecting vertical delay is located at the bottom of quadrant 1 or quadrant 2, each time the vertical delay is adjusted, it is determined whether the light intensity of quadrant 1 or quadrant 2 reaches a maximum value, and whether the corresponding light intensity of quadrant 3 or quadrant 4 is 0; if so, it is determined that the actual position of the image for detecting vertical delay on the QPD vertically coincides with the target position of the image for detecting vertical delay;

[0029] If the target position of the image for detecting vertical delay is located at the top of the 3rd or 4th quadrant, each time the vertical delay is adjusted, it is determined whether the corresponding light intensity of the 1st or 2nd quadrant is 0, and whether the light intensity of the 3rd or 4th quadrant reaches the maximum value; if so, it is determined that the actual position of the image for detecting vertical delay on the QPD vertically coincides with the target position of the image for detecting vertical delay.

[0030] Optionally, the grayscale of the image for detecting vertical delay gradually increases or decreases from top to bottom; the method further includes:

[0031] During the process of adjusting the vertical delay, the QPD is controlled to collect and calculate the change in the light intensity of the detection image in quadrant 1 or quadrant 3, or the change in the light intensity in quadrant 2 or quadrant 4 is calculated, and whether the adjustment direction of the vertical delay is correct is determined based on the change in the light intensity and a pre-set judgment rule; if correct, continue to adjust the vertical delay; if incorrect, adjust the vertical delay in the opposite direction.

[0032] Optionally, the determination rule refers to:

[0033] If the vertical target position is located at the bottom of quadrant 1 or quadrant 2, and the grayscale of the image for detecting vertical delay gradually increases from top to bottom, then during the process of adjusting the vertical delay, if the change in the light intensity of quadrant 1 or quadrant 2 gradually increases, it is determined that the adjustment direction is correct;

[0034] If the vertical target position is located at the bottom of quadrant 1 or quadrant 2, and the grayscale of the image for detecting the vertical delay gradually decreases from top to bottom, then during the process of adjusting the vertical delay, if the change in the light intensity of quadrants 1 and 2 gradually decreases, then it is determined that the adjustment direction is correct;

[0035] If the vertical target position is located at the top of the three or four quadrants, and the grayscale of the image for detecting the vertical delay gradually increases from top to bottom, then during the process of adjusting the horizontal delay, if the change in the light intensity of the three or four quadrants gradually decreases, it is determined that the adjustment direction is correct;

[0036] If the vertical target position is located at the top of the 3rd or 4th quadrant, and the grayscale of the image for detecting the vertical delay gradually decreases from top to bottom, then during the process of adjusting the vertical delay, if the change in the light intensity of the 3rd or 4th quadrant gradually increases, it is determined that the adjustment direction is correct.

[0037] A second aspect of an embodiment of the present invention provides a projection display device, which includes an image light source, a detection light source, an optical fiber scanner, a spectrometer, a four-quadrant photodiode QPD and a computer-readable storage medium arranged in sequence along an optical path. The light emitted by the image light source and the detection light source is coupled into the optical fiber scanner. After the light emitted by the optical fiber scanner is split by the spectrometer, the light emitted by the detection light source is projected onto the QPD to form a detection image, and the light emitted by the image light source is used to form a projection image; a computer program is stored on the readable storage medium, and when the computer program is executed by the processor, the processor executes the method described in the first aspect.

[0038] One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

[0039] In the solution of the embodiment of the present invention, the detection image information is inserted into the image to be projected to generate an image to be projected that carries the detection light information. Then, during the process of adjusting the delay between the light source and the fiber optic scanner, the position of the detection image on the QPD is used to determine whether the delay between the light source and the fiber optic scanner is aligned, thereby ensuring the delay alignment between the image light source and the fiber optic scanner to achieve normal projection display.

[0040] Furthermore, in the solution of the embodiment of the present invention, a QPD sensor is used to collect the light intensity of the detection image in the four quadrants of the QPD sensor, and the actual position of the detection image on the QPD sensor is determined based on the light intensity of the detection image in the four quadrants of the QPD sensor. Then, by judging whether the actual position of the detection image coincides with the target position, it is judged whether the delay alignment between the detection light source and the fiber scanner is achieved. Since the QPD sensor and the corresponding signal processing are both necessary parts for feedback detection, the feedback detection device in the embodiment of the present invention is easier to complete circuit-level integration with the projection system. After the feedback detection device is chip-based, it has advantages in reducing system complexity, especially when used in projection systems with special requirements on volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive work.

[0042] Figure 1A and Figure 1B is a schematic diagram of a fiber scanning projection system in an embodiment of the present invention;

[0043] Figure 2 A schematic diagram of feedback optical path generation in an embodiment of the present invention;

[0044] Figure 3 is a block diagram of a QPD sensor data acquisition module circuit in an embodiment of the present invention;

[0045] Figure 4 Schematic diagram of the delay adjustment method in an embodiment of the present invention;

[0046] Figure 5 is a schematic diagram of a projected image with detection light information in an embodiment of the present invention;

[0047] Figure 6 Schematic diagram of the four quadrants of the QPD sensor in an embodiment of the present invention;

[0048] Figure 7 A schematic diagram of the position of an image for possible detection of horizontal delay in an embodiment of the present invention;

[0049] Figure 8 Schematic diagram of another possible position of an image for detecting horizontal delay in an embodiment of the present invention;

[0050] Figure 9 A schematic diagram of possible image positions for detecting vertical delay in an embodiment of the present invention;

[0051] Figure 10 FIG. 4 is a schematic diagram of another possible position of an image for detecting vertical delay in an embodiment of the present invention. DETAILED DESCRIPTION

[0052] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0053] In this manual, we first explain the fiber optic scanning projection system. The fiber optic scanning projection system uses the actuator in the fiber optic scanner to drive the optical fiber to vibrate at high speed, and cooperates with the laser modulation algorithm to realize the display of image information. Figure 1A As shown, an existing fiber optic scanning projection system mainly includes: a processor 100 , a laser module 110 , a fiber optic scanner 120 , a transmission fiber 130 , a light source modulation circuit 140 , a scanning drive circuit 150 and a beam combining unit 160 .

[0054] The processor 100 may be a graphics processing unit (GPU), a central processing unit (CPU), or other chips or circuits with control functions and image processing functions, which are not specifically limited here.

[0055] When the system is working, the processor 100 can control the light source modulation circuit 140 to modulate the laser module 110 according to the image data to be displayed. The laser module 110 includes multiple monochromatic lasers, each emitting a light beam of different colors. Figure 1AAs can be seen in FIG, the laser module can specifically use three lasers: red (Red, R), green (Green, G), and blue (Blue, B). The beams emitted by the lasers in the laser module 110 are combined into a single laser beam by the beam combining unit 160 and coupled into the transmission optical fiber 130.

[0056] The processor 100 may also control the scanning driving circuit 150 to drive the optical fiber scanner 120 to scan, thereby scanning and outputting the light beam transmitted in the transmission optical fiber 130 .

[0057] The light beam output by the optical fiber scanner 120 acts on a certain pixel position on the surface of the medium and forms a light spot at the pixel position, thereby realizing the scanning of the pixel position. Driven by the optical fiber scanner 120, the output end of the transmission optical fiber 130 sweeps along a certain scanning trajectory, so that the light beam moves to the corresponding pixel position for scanning. During the actual scanning process, the light beam output by the transmission optical fiber 130 will form a light spot with corresponding image information (such as color, grayscale or brightness) at each pixel position. In one frame of time, the light beam traverses each pixel position at a sufficiently high speed to complete the scanning of one frame of image. Due to the characteristic of "visual residual" when the human eye observes things, the human eye cannot perceive the movement of the light beam at each pixel position, but sees a complete frame of image.

[0058] Continue to refer Figure 1B , which shows the structure of an existing fiber optic scanner 120, primarily comprising: a piezoelectric actuator 121, a fiber optic cantilever 122, a lens 123, a scanner housing 124, and a fixture 125. The piezoelectric actuator 121 is secured to the scanner housing 124 via the fixture 125. A transmission fiber 130 extends from the free end of the piezoelectric actuator 121 to form the fiber optic cantilever 122 (also referred to as a scanning fiber). During operation, the piezoelectric actuator 121 vibrates along the Y-axis and X-axis directions under the influence of a scanning drive signal. Driven by the piezoelectric actuator 121, the free end of the fiber optic cantilever 122 sweeps along a predetermined trajectory and emits a light beam. This emitted light beam then passes through the lens 123 and scans the surface of the medium. The Y-axis is also called the slow axis, and the X-axis is also called the fast axis. The Y-axis intersects the X-axis. Obviously, the Y-axis and the X-axis can be perpendicular.

[0059] Please refer to Figure 2In an embodiment of the present invention, the projection display device includes an image light source, a detection light source, and an optical fiber scanner. The light emitted by the image light source and the detection light source is coupled into the same optical fiber scanner. The detection light source uses an invisible band light wave with strong resistance to ambient light interference, and together with the visible light in the projection display, projects the light through the optical fiber scanner and the projection lens. Because the existing high-definition infrared camera sensor has a response wavelength limitation, and the response wavelength is close to the infrared wavelength existing in the ambient light. In actual use scenarios, especially when there is sunlight, it is difficult to eliminate the interference of infrared light in the ambient light, and the anti-infrared interference capability is poor. In an embodiment of the present invention, an invisible band light wave with strong resistance to ambient light interference is used. For example, the wavelength of the invisible light band can be 940nm or 980nm. Light emitted from the projection lens passes through a spectrometer, which separates a portion of the light energy at a specific power ratio. This energy is then transmitted through a specific wavelength attenuator to a QPD (quadrantal photodiode) sensor. Alternatively, the spectrometer can be used to separate the light at different wavelengths, with the invisible light used for detection being directed to the QPD sensor to form a detection image. Light emitted from the image light source passes through the spectrometer to form the projected image. The QPD sensor signal is then collected and calculated to determine whether the position of the detection image on the QPD sensor meets specific requirements. In this embodiment of the present invention, the QPD sensor is a 2x2 pixel PD sensor.

[0060] In the embodiment of the present invention, the implementation of QPD detection includes three parts: feedback optical path generation, sensor data processing, and software algorithm recognition. Next, the implementation principle of QPD detection is explained.

[0061] Feedback is generated by optical path

[0062] In the embodiment of the present invention, the optical path diagram of the feedback light is as follows: Figure 2 As shown. After the light is emitted from the projection lens, it passes through a beam splitter placed at 45 degrees. Most of the light energy emitted by the lens passes through the beam splitter to form an optical path for the projection image. A small part of the light emitted by the lens is reflected and directly projected onto the QPD sensor. In an embodiment of the present invention, the projection display device includes a focusing lens, which is arranged on the output optical path of the beam splitter. After the light corresponding to the detection image is focused by the focusing lens, it is incident on the QPD sensor, so that the detection image projected on the QPD sensor is proportionally scaled with the scanned image of the optical fiber scanner. The actual position of the detection image on the QPD sensor is obtained by analysis and calculation by the QPD sensor processing unit. Therefore, by judging whether the actual position detected on the QPD sensor coincides with the target position, it is judged whether the light source and the optical fiber scanner are time-delay aligned.

[0063] QPD sensor data processing

[0064] Through the aforementioned optical path splitting structure, the light beam emitted by the fiber scanner can be irradiated onto the target surface of the QPD sensor for feedback. Combined with the corresponding photoelectric characteristics of the QPD sensor and the corresponding circuit, the QPD sensor data collection and analysis can be completed. The circuit block diagram of the QPD sensor data acquisition module is shown in the figure. Figure 3 shown.

[0065] The QPD sensor data acquisition module circuit is divided into three parts: sensor signal amplification circuit, AD (analog signal to digital signal conversion) conversion circuit, and data operation unit.

[0066] Sensor signal amplification circuit

[0067] A QPD sensor is essentially a photodiode sensor. When a reverse voltage is applied across the PD, a reverse current is generated in the PD. This current is linearly proportional to the light intensity and is commonly referred to as the photocurrent. This photocurrent directly reflects the light intensity in each quadrant.

[0068] The photocurrent generated by the QPD sensor is a very weak current signal, which needs to be converted into a corresponding voltage signal using an I / V (current-to-voltage conversion) conversion circuit. Figure 3 A set of voltage amplifiers is then used to amplify the voltage signal to an appropriate level for signal conversion in the subsequent AD sampling circuit.

[0069] AD conversion circuit

[0070] The QPD photocurrent signal is scaled by a two-stage amplifier to output an analog voltage signal that is linearly proportional to the light intensity in each quadrant. To facilitate subsequent data processing by the data processing unit, this analog signal needs to be discretely digitized. Figure 3 The analog-to-digital conversion circuit in the block diagram is responsible for digitizing the analog signal output by the op amp. Its output is binary data, which is proportional to the amplitude of the analog signal output by the op amp.

[0071] Data processing unit

[0072] This component can be an integrated circuit unit with data computing capabilities, such as an MCU (Microcontroller Unit), a DSP (Digital Signal Processor), a CPU (Central Processing Unit), or an FPGA (Field Programmable Gate Array). It collects, calculates, and analyzes the aforementioned photocurrent data to calculate the actual position of the detection image.

[0073] Software Algorithm

[0074] An invisible light wave for feedback detection is output using a known pattern of image modulation. During the projection display process, the illumination intensity of the detection image on the PD sensor in each of the four quadrants is collected. The delay adjustment method described in an embodiment of the present invention is then used to adjust the delay between the detection light source and the fiber scanner. For example, the known pattern of image modulation can be a horizontal or vertical image with a certain width, output through image modulation. The detection image can also be understood as a square display area.

[0075] Please refer to Figure 4 The delay adjustment method in the embodiment of the present invention includes the following steps.

[0076] Step 401 : Acquire an image to be projected, and insert detection image information into the image to be projected to generate an image to be projected with detection light information.

[0077] The image to be projected refers to an image that can be viewed by the user, such as a system interface, a video player, etc. The image light source can be an RGB light source, and correspondingly, the image to be projected is an RGB image. As mentioned above, the detection light information can be an invisible band light wave for delay adjustment. The image to be projected with the detection light information is as follows: Figure 5 As shown, 501 represents the image to be projected, and the area indicated by the rectangular dashed box is the inserted detection light information. In this embodiment of the present invention, the image to be projected and the detection image can be images of the same display specifications. When inserting the detection light information, the corresponding pixel information on the detection image is inserted into each pixel of the image to be projected. In other embodiments, the detection light information can also be inserted into a specific image area of ​​the image to be projected.

[0078] In the embodiment of the present invention, the delay adjustment may be performed when the projection display device is started, or in real time or periodically during the projection process, or according to a user instruction, and the present invention does not impose any limitation on this.

[0079] Step 402 : Control the light source to output light corresponding to the image to be projected with the detection light information, and adjust the delay between the light source and the fiber scanner.

[0080] In an embodiment of the present invention, a detection light source is modulated with a specific detection image, and the light emitted by the detection light source and the light emitted by the image light source modulated by the projection image are coupled into the same optical fiber scanner to form an image to be projected, so that the scanning trajectory of the detection light and the scanning trajectory of the image light completely overlap.

[0081] Among them, the delay includes horizontal delay and vertical delay; the horizontal delay refers to the delay between the first pixel of a row and the starting point of the scanning trajectory of the row of images when displaying a row of images; the vertical delay refers to the delay between the first row of pixels of a frame of images and the first row of scanning trajectory of the frame of images when displaying a frame of images.

[0082] In the embodiments of the present invention, the delay is due to the damping effect of the actual system, which causes a time difference (time difference) between the actual optical fiber vibration trajectory and the drive signal or laser light source response signal. The delay can be adjusted by adjusting the light source emission time or the starting phase of the fiber scanner's drive signal, which is not limited to this invention.

[0083] Step 403 : During the process of adjusting the delay, controlling the QPD to collect the light intensity of the detection image in the four quadrants of the QPD.

[0084] In the embodiment of the present invention, the light intensity can be collected at a certain position of the QPD sensor, indicating that there is light irradiation at that position. Therefore, by collecting the light intensity of the detection image in the four quadrants of the QPD sensor, the position of the detection image in the QPD sensor can be reflected.

[0085] Step 404 : Determine the actual position of the detection image on the QPD based on the light intensity in the four quadrants of the QPD, and stop adjusting the delay until the actual position of the detection image on the QPD coincides with the target position.

[0086] The target position refers to the position of the detection image on the QPD sensor during delay alignment. For a frame of image, the position of a specific image area on the image to be projected is fixed. Correspondingly, during normal display, the display area of ​​the specific image area on the imaging interface is also fixed. In other words, during delay alignment, the display area of ​​the detection image on the QPD sensor is also fixed. Since the detection image projected onto the QPD sensor is proportionally scaled to the scanned image of the fiber optic scanner, the delay alignment of the image to be projected can be determined by determining whether the detection image is aligned. If the actual position of the detection image coincides with the target position, it means that the delay alignment between the detection light source and the fiber optic scanner is achieved.

[0087] In this embodiment of the present invention, the detection image information is inserted into the image to be projected, generating a projected image that carries the detection light information. Then, during the delay adjustment between the light source and the fiber scanner, the position of the detection image on the QPD is used to determine whether the delay between the light source and the fiber scanner is aligned. This ensures the delay alignment between the image light source and the fiber scanner, enabling proper projection and display.

[0088] Furthermore, in the solution of the embodiment of the present invention, a QPD sensor is used to perform feedback detection on the position of the detection image. Since the QPD sensor and the corresponding signal processing are both necessary parts for feedback detection, the feedback detection device in the embodiment of the present invention is easier to complete circuit-level integration with the projection system. After the feedback detection device is chip-based, it is more advantageous to reduce system complexity, especially when used in projection systems with special requirements on volume.

[0089] In an embodiment of the present invention, the delay includes horizontal delay and vertical delay. The horizontal delay can be adjusted first, and then the vertical delay can be adjusted after the horizontal delays are aligned. Correspondingly, the detection image includes an image for detecting horizontal delay and an image for detecting vertical delay. During the process of adjusting the horizontal delay, the image for detecting horizontal delay is inserted into the image to be projected, and the light source is controlled to output light detection information in the image for detecting horizontal delay. During the process of adjusting the vertical delay, the image for detecting vertical delay is inserted into the image to be projected, and the light source is controlled to output light detection information in the image for detecting vertical delay. The image for detecting horizontal delay and the image for detecting vertical delay can be the same or different.

[0090] In the embodiment of the present invention, Figure 6 As shown, the four quadrants of the QPD sensor are distributed in a field shape, including quadrants 1 and 2 located at the top, and quadrants 3 and 4 located at the bottom.

[0091] In the embodiment of the present invention, the target position of the detection image on the QPD sensor is different, and the corresponding delay adjustment method is also different.

[0092] In the process of adjusting the horizontal delay, assuming that the target position of the image for detecting the horizontal delay is located at the rightmost side of quadrant 1 or the leftmost side of quadrant 2, the corresponding delay adjustment method is: adjust the vertical delay and horizontal delay so that the image for detecting the horizontal delay moves vertically within the display area until the light intensity of the image for detecting the horizontal delay in quadrants 3 and 4 is 0, and the light intensity of quadrants 1 and 2 is not 0; then, adjust the horizontal delay so that the image for detecting the horizontal delay moves horizontally within the display area.

[0093] When the image with horizontal delay is moving horizontally in the display area, there are two situations in determining the actual position of the image on the QPD sensor.

[0094] The first case, such as Figure 7 As shown in (a), if the target position of the image for detecting horizontal delay is located at the rightmost side of quadrant 1, each time the horizontal delay is adjusted, it is determined whether the illumination intensity of quadrant 1 reaches the maximum value and whether the illumination intensity of quadrant 2 is 0; if so, it is determined that the image for detecting horizontal delay is located at the rightmost side of quadrant 1, that is, the actual position of the image for detecting horizontal delay coincides horizontally with the target position of the image for detecting horizontal delay; if not, the horizontal delay is continuously adjusted so that the image for detecting horizontal delay is shifted to the left, as shown in FIG. Figure 7 As shown in (b) in .

[0095] The second case, such as Figure 8 As shown in (a), if the target position of the image for detecting horizontal delay is located at the leftmost side of the 2nd quadrant, each time the horizontal delay is adjusted, it is determined whether the light intensity of the 1st quadrant is 0 and whether the light intensity of the 2nd quadrant reaches the maximum value; if so, it is determined that the image for detecting horizontal delay is located at the leftmost side of the 2nd quadrant, that is, the actual position of the image for detecting horizontal delay coincides horizontally with the target position of the image for detecting horizontal delay; if not, the horizontal delay is continued to be adjusted so that the image for detecting horizontal delay is shifted to the right, as shown in FIG. Figure 8 As shown in (b) in .

[0096] In an embodiment of the present invention, the target position of the image for detecting horizontal delay may also be located at the rightmost side of quadrant 3 or the leftmost side of quadrant 4, and the corresponding delay adjustment method will also change, which will not be described in detail in the present invention.

[0097] It should be noted that the horizontal coincidence of the actual position of the image for detecting horizontal delay and the target position means that the positions of the two are coincident in the horizontal direction, and the positions in the vertical direction are not limited and may or may not be coincident.

[0098] In an embodiment of the present invention, in order to accurately determine the movement direction of the detection image during the delay adjustment process, the image for detecting the horizontal delay can be a non-uniform grayscale image, so that in the process of adjusting the delay, the light intensity in the four quadrants changes non-uniformly; in the process of adjusting the horizontal delay, the adjustment direction of the horizontal delay is determined by the change in the light intensity in the four quadrants, and the horizontal delay is continued to be adjusted according to the adjustment direction of the horizontal delay.

[0099] In one energy-saving embodiment, the grayscale of the image used to detect horizontal delay can be set to gradually increase or decrease from left to right. For example, if the delay is adjusted by adjusting the starting phase of the fiber scanner, if the horizontal delay exceeds 180 degrees, the left and right sides of the projected image will be reversed. Therefore, the grayscale of the image used to detect horizontal delay can be set to gradually increase or decrease from left to right. Then, for each step of delay adjustment, the direction of adjustment of the horizontal delay phase is determined by calculating the change in light intensity between quadrants 1 and 2, or by calculating the change in light intensity between quadrants 3 and 4.

[0100] Specifically, in the process of adjusting the horizontal delay, the QPD sensor is controlled to collect and calculate the change in light intensity of the image of the detected horizontal delay in quadrant 1 or quadrant 2, and whether the adjustment direction of the detected image is correct is determined based on the change in light intensity and a pre-set judgment rule; if correct, continue to adjust the horizontal delay; if incorrect, adjust the horizontal delay in the opposite direction.

[0101] The determination rule is that if the target position of the image for detecting the horizontal delay is located at the rightmost side of the first quadrant, and the grayscale of the image for detecting the horizontal delay gradually increases from left to right, then during the process of adjusting the horizontal delay, if the change in the illumination intensity of the first quadrant gradually increases, it is determined that the adjustment direction of the horizontal delay is correct.

[0102] If the target position of the image for detecting the horizontal delay is located at the rightmost side of the first quadrant, and the grayscale of the image for detecting the horizontal delay gradually decreases from left to right, then during the process of adjusting the horizontal delay, if the change in the light intensity of the first quadrant gradually decreases, then it is determined that the adjustment direction of the horizontal delay is correct;

[0103] If the target position of the image for detecting horizontal delay is located at the leftmost side of the two quadrants, and the grayscale of the image for detecting horizontal delay gradually increases from left to right, then during the process of adjusting the horizontal delay, if the change in the light intensity of the two quadrants gradually decreases, it is determined that the adjustment direction of the horizontal delay is correct;

[0104] If the target position of the image for detecting horizontal delay is located at the leftmost side of the 2nd quadrant, and the grayscale of the image for detecting horizontal delay gradually decreases from left to right, then during the process of adjusting the horizontal delay, if the change in the light intensity of the 2nd quadrant gradually increases, it is determined that the adjustment direction of the horizontal delay is correct.

[0105] In an embodiment of the present invention, the target position of the image for detecting horizontal delay can also be located at the rightmost side of quadrant 3 or the leftmost side of quadrant 4. The corresponding delay adjustment method is: adjusting the vertical delay so that the image for detecting horizontal delay moves vertically within the display area until the illumination intensity of the image for detecting horizontal delay in quadrants 1 and 2 is both 0 and the illumination intensity in quadrants 3 and 4 is non-zero; then, adjusting the horizontal delay so that the image for detecting horizontal delay moves horizontally within the display area. When determining the actual position of the image for detecting horizontal delay on the QPD sensor, the determination is made by collecting the illumination intensity of the image for detecting horizontal delay in quadrants 3 and 4. This specification will not further elaborate on this.

[0106] In the embodiment of the present invention, after the horizontal delays are aligned, the vertical delay is adjusted.

[0107] During the process of adjusting the vertical delay, if the target position of the image for detecting the vertical delay is located at the bottom of quadrant 1 or the top of quadrant 3, the corresponding delay adjustment method is: adjust the horizontal delay so that the image for detecting the vertical delay moves horizontally within the display area until the light intensity of the image for detecting the vertical delay in quadrants 2 and 4 is 0 and the light intensity in quadrants 1 and 3 is not 0; then, adjust the vertical delay so that the image for detecting the vertical delay moves vertically within the display area.

[0108] When the image with vertical delay is detected and moves vertically within the display area, there are two situations in determining the actual position of the image on the QPD sensor.

[0109] The first case, such as Figure 9 As shown, if the target position of the image for detecting vertical delay is located at the bottom of quadrant 1, each time the vertical delay is adjusted, it is determined whether the light intensity of quadrant 1 reaches the maximum value and whether the light intensity of quadrant 3 is 0; if so, it is determined that the image for detecting vertical delay is moved to the bottom of quadrant 1, that is, the actual position of the image for detecting vertical delay is vertically overlapped with the target position of the image for detecting vertical delay; if not, the vertical delay is continued to be adjusted so that the image is translated upward, as shown in FIG. Figure 9 As shown in (b) in .

[0110] The second case, such as Figure 10 As shown in (a), if the target position of the image for detecting vertical delay is located at the top of the three quadrants, each time the vertical delay is adjusted, it is determined whether the light intensity of the first quadrant is 0 and whether the light intensity of the three quadrants reaches the maximum value; if so, it is determined that the image for detecting vertical delay is moved to the top of the three quadrants, that is, the actual position of the image for detecting vertical delay is vertically coincident with the target position of the image for detecting vertical delay; if not, the vertical delay is continued to be adjusted so that the image is translated downward, as shown in FIG. Figure 10 As shown in (b) in .

[0111] In an embodiment of the present invention, the target position of the image for detecting vertical delay may also be located at the bottom of the second quadrant or the top of the fourth quadrant, and the corresponding delay adjustment method will also change, which will not be described in detail herein.

[0112] It should be noted that the vertical overlap of the actual position of the image for detecting vertical delay and the target position means that the positions of the two in the vertical direction are overlapped, and the positions in the horizontal direction are not limited and may or may not overlap. In an embodiment of the present invention, if the image for detecting horizontal delay and the image for detecting vertical delay are the same, after the horizontal delay is aligned, the vertical delay is adjusted, then when the vertical delay is aligned, the actual position of the image completely overlaps with the target position. If the image for detecting horizontal delay and the image for detecting vertical delay are different, then in the process of adjusting the horizontal delay, the actual position of the image for detecting horizontal delay overlaps horizontally with the corresponding target position, and in the process of adjusting the vertical delay, the actual position of the image for detecting vertical delay overlaps vertically with the corresponding target position.

[0113] Similarly, in an embodiment of the present invention, to accurately determine the direction of motion of the image used to detect vertical delay during delay adjustment, one possible implementation may be to set the grayscale of the image used to detect vertical delay to gradually increase or decrease from top to bottom. Then, with each delay adjustment step, the direction of delay phase adjustment is determined by calculating the change in illumination intensity in quadrant 1 or quadrant 3.

[0114] Specifically, in the process of adjusting the vertical delay, the QPD sensor is controlled to collect the change in light intensity of the image for detecting the vertical delay in quadrant 1 or quadrant 3, and whether the adjustment direction of the detected image is correct is determined based on the change in light intensity and a pre-set judgment rule; if correct, continue to adjust the vertical delay; if incorrect, adjust the vertical delay in the opposite direction.

[0115] The determination rule is that if the vertical target position is at the bottom of the first quadrant and the grayscale of the image for detecting the vertical delay gradually increases from top to bottom, then during the process of adjusting the vertical delay, if the change in the illumination intensity of the first quadrant gradually increases, it is determined that the adjustment direction of the vertical delay is correct;

[0116] If the target position of the image for detecting the vertical delay is located at the bottom of the first quadrant, and the grayscale of the image for detecting the vertical delay gradually decreases from top to bottom, then during the process of adjusting the vertical delay, if the change in the light intensity of the first quadrant gradually decreases, then it is determined that the adjustment direction of the vertical delay is correct;

[0117] If the target position of the image for detecting vertical delay is located at the top of the three quadrants and the grayscale of the image for detecting vertical delay gradually increases from top to bottom, then during the process of adjusting the horizontal delay, if the change in the light intensity of the third quadrant gradually decreases, it is determined that the adjustment direction of the vertical delay is correct;

[0118] If the target position of the image for detecting the vertical delay is located at the top of the three quadrants, and the grayscale of the detection image gradually decreases from top to bottom, then during the process of adjusting the vertical delay, if the change in the light intensity of the third quadrant gradually increases, it is determined that the adjustment direction of the vertical delay is correct.

[0119] In an embodiment of the present invention, the target position of the image for detecting vertical delay can also be located at the bottom of quadrant 2 or the top of quadrant 4. The corresponding delay adjustment method is: adjusting the horizontal delay so that the image for detecting vertical delay moves horizontally within the display area until the light intensity of the image for detecting vertical delay is 0 in quadrants 1 and 3 and non-zero in quadrants 2 and 4; then, adjusting the vertical delay so that the image for detecting vertical delay moves vertically within the display area. When determining the actual position of the image for detecting vertical delay on the QPD sensor, the determination is made by collecting the light intensity of the image for detecting vertical delay in quadrants 2 and 4. This specification will not be further described in detail.

[0120] Next, the delay adjustment method in the embodiment of the present invention is described through a specific adjustment example. Among them, quadrant 1, quadrant 2, quadrant 3 and quadrant 4 are also referred to as PD1, PD2, PD3 and PD4. Figure 7 As shown in (a), it is the case of horizontal delay alignment, such as Figure 7(b) in the figure shows a horizontal delay misalignment. When this occurs, the detection image can appear anywhere in the display area. By adjusting the horizontal and vertical delays, ensure that the PD3 and PD4 values ​​are 0, and the PD1 and PD2 values ​​are not 0. This ensures that the image appears only in the upper half of the display area.

[0121] Since PD1 and PD2 are not 0 at the same time, the actual display position of the image is roughly as follows Figure 7 As shown in the image (b) on the right, only the horizontal delay is adjusted to shift the image within the display area. During the shift, if the PD1 value decreases, the PD2 value increases. Otherwise, the PD1 value increases and the PD2 value decreases. By evaluating the increase and decrease of PD1 and PD2, it is determined whether the image is moving toward PD1 or PD2. When PD2 is exactly 0 and PD1 is exactly at its maximum value, the image is considered horizontally aligned.

[0122] If the horizontal delay exceeds 180 degrees, the left and right images will be reversed. Alternatively, you can display an image with increasing grayscale values ​​from left to right. During the horizontal delay adjustment process, the delay phase is determined by simultaneously determining the change in PD1 and PD2 with each adjustment step. If PD1 increases, and the change in PD1 increases with each adjustment step, the leftward adjustment is correct. Similarly, when PD2 is exactly 0 and PD1 is exactly at its maximum value, the image is considered horizontally aligned.

[0123] After horizontal delay alignment, the vertical delay adjustment method and judgment criteria are similar. Simply adjust the image style during horizontal delay adjustment to a grayscale that increases or decreases gradually from top to bottom. This manual will not go into detail here.

[0124] Based on the same inventive concept, an embodiment of the present invention also provides a projection display device, which includes an image light source, a detection light source, an optical fiber scanner, a spectrometer, a four-quadrant photodiode QPD and a computer-readable storage medium arranged in sequence along the optical path. The light emitted by the image light source and the detection light source is coupled into the optical fiber scanner. The optical fiber scanner vibrates under the action of the driving signal. After the light emitted by the optical fiber scanner is split by the spectrometer, the light emitted by the detection light source is projected onto the QPD to form a detection image. The light emitted by the image light source is used to form a projection image. The readable storage medium stores a computer program, and when the computer program is executed by the processor, the steps of the above-mentioned delay adjustment method are implemented.

[0125] In an embodiment of the present invention, the projection display device can be an AR (English full name: Augmented Reality; Chinese name: Augmented Reality) device, a laser TV, a laser projector, etc. In these projection display devices, a fiber optic scanner can be used for projection display, or multiple fiber optic scanners can be spliced ​​together for display. The present invention does not impose any restrictions on this.

[0126] All features disclosed in this specification, or all steps in the disclosed methods or processes, except mutually exclusive features and / or steps, can be combined in any manner.

[0127] Any feature disclosed in this specification (including any appended claims, abstract and drawings), unless otherwise stated, may be replaced by other equivalent or similar features. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0128] The present invention is not limited to the aforementioned specific embodiments, but extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims

1. A delay adjustment method, applied to a projection display device, characterized in that: The projection display device includes a light source, a fiber scanner, a light splitting device and a four-quadrant photodiode QPD; The light source includes an image light source and a detection light source; and the method includes: Acquire an image to be projected, and insert detection image information into the image to be projected to generate an image to be projected with detection light information; Controlling the light source to output light corresponding to the image to be projected with detection light information, and adjusting the delay between the light source and the fiber scanner; wherein the light emitted by the image light source and the detection light source is coupled into the fiber scanner, and after the light emitted by the fiber scanner is split by the spectrometer, the light emitted by the detection light source is projected onto the QPD to form a detection image, and the light emitted by the image light source is used to form a projection image; During the process of adjusting the delay, the QPD is controlled to collect the light intensity of the detection image in the four quadrants of the QPD, and the actual position of the detection image on the QPD is determined based on the light intensity in the four quadrants of the QPD. The delay adjustment is stopped until the actual position of the detection image on the QPD coincides with the target position.

2. The method according to claim 1, wherein The delay includes horizontal delay and vertical delay; the horizontal delay refers to the delay between the first pixel and the starting point of the scanning trajectory of the image in this row when displaying a row of images; the vertical delay refers to the delay between the first row of pixels and the first row of scanning trajectory of the image in this frame when displaying a frame of images.

3. The method according to claim 2, wherein The detection image is a non-uniform grayscale image, so that during the process of adjusting the delay, the illumination intensity in the four quadrants changes non-uniformly; the method includes: During the process of adjusting the delay, the variation of the light intensity in the four quadrants is calculated, the adjustment direction of the delay is determined according to the variation, and the delay is continuously adjusted according to the adjustment direction of the delay.

4. The method according to claim 2, wherein The detecting image includes detecting an image of horizontal delay and detecting an image of vertical delay; and adjusting the delay between the light source and the optical fiber scanner includes: Adjusting the delay according to a delay adjustment method corresponding to the target position of the image for detecting the horizontal delay until the actual position of the image for detecting the horizontal delay is horizontally coincident with the target position of the image for detecting the horizontal delay, and stopping adjusting the horizontal delay; The delay is adjusted according to the delay adjustment method corresponding to the target position of the image for detecting vertical delay, until the actual position of the image for detecting vertical delay vertically coincides with the target position of the image for detecting vertical delay, and the vertical delay adjustment is stopped.

5. The method according to claim 4, wherein The four quadrants of the QPD are arranged in a field shape, with quadrants 1 and 2 located at the top, and quadrants 3 and 4 located at the bottom, and quadrants 1 and 3 located on the left, and quadrants 2 and 4 located on the right; the target position of the image for detecting horizontal delay is located at the rightmost side of quadrant 1 or quadrant 3, or at the leftmost side of quadrant 2 or quadrant 4; and the delay is adjusted according to a delay adjustment method corresponding to the target position of the image for detecting horizontal delay until the actual position of the image for detecting horizontal delay horizontally coincides with the target position of the image for detecting horizontal delay, including: Adjusting the vertical delay and the horizontal delay until the image for detecting the horizontal delay is located in quadrants 1 and 2, and the light intensity values ​​of quadrants 1 and 2 are not 0, or until the image for detecting the horizontal delay is located in quadrants 3 and 4, and the light intensity values ​​of quadrants 3 and 4 are not 0; If the target position of the image for detecting horizontal delay is located at the rightmost side of quadrant 1 or quadrant 3, each time the horizontal delay is adjusted, it is determined whether the light intensity of quadrant 1 or quadrant 3 reaches a maximum value, and whether the corresponding light intensity of quadrant 2 or quadrant 4 is 0; if so, it is determined that the actual position of the image for detecting horizontal delay on the QPD horizontally coincides with the target position of the image for detecting horizontal delay; If the target position of the image for detecting horizontal delay is located at the leftmost side of quadrant 2 or quadrant 4, each time the horizontal delay is adjusted, it is determined whether the light intensity of quadrant 1 or quadrant 3 is 0, and whether the corresponding light intensity of quadrant 2 or quadrant 4 reaches the maximum value; if so, it is determined that the actual position of the image for detecting horizontal delay on the QPD coincides horizontally with the target position of the image for detecting horizontal delay.

6. The method according to claim 5, wherein The grayscale of the image for detecting horizontal delay gradually increases or decreases from left to right; the method further includes: During the process of adjusting the horizontal delay, the QPD is controlled to collect and calculate the change in light intensity of the image detecting the horizontal delay in quadrant 1 or quadrant 2, or the change in light intensity of quadrant 3 or quadrant 4 is calculated, and whether the adjustment direction of the horizontal delay is correct is determined based on the change in light intensity and a pre-set judgment rule; if correct, continue to adjust the horizontal delay; if incorrect, adjust the horizontal delay in the opposite direction.

7. The method according to claim 6, wherein The judgment rules are: If the horizontal target position is located at the rightmost side of quadrant 1 or quadrant 3, and the grayscale of the image for detecting the horizontal delay gradually increases from left to right, then during the process of adjusting the horizontal delay, if the change in the light intensity of quadrant 1 or quadrant 3 gradually increases, it is determined that the adjustment direction is correct; If the horizontal target position is located at the rightmost side of quadrant 1 or quadrant 3, and the grayscale of the image for detecting the horizontal delay gradually decreases from left to right, then during the process of adjusting the horizontal delay, if the change in the light intensity of quadrant 1 or quadrant 3 gradually decreases, it is determined that the adjustment direction is correct; If the horizontal target position is located at the leftmost side of quadrant 2 or quadrant 4, and the grayscale of the image for detecting the horizontal delay gradually increases from left to right, then during the process of adjusting the horizontal delay, if the change in the light intensity of quadrant 2 or quadrant 4 gradually decreases, it is determined that the adjustment direction is correct; If the horizontal target position is located at the leftmost side of the 2nd or 4th quadrant, and the grayscale of the image detecting the horizontal delay gradually decreases from left to right, then during the process of adjusting the horizontal delay, if the change in the light intensity of the 2nd or 4th quadrant gradually increases, it is determined that the adjustment direction is correct.

8. The method according to claim 4, wherein The four quadrants of the QPD are arranged in a field shape, with quadrants 1 and 2 located at the top, and quadrants 3 and 4 located at the bottom, and quadrants 1 and 3 located on the left, and quadrants 2 and 4 located on the right; the target position of the image for detecting vertical delay is located at the bottom of quadrant 1 or quadrant 2, or at the top of quadrant 3 or quadrant 4; and the delay is adjusted according to a delay adjustment method corresponding to the target position of the image for detecting vertical delay until the actual position of the image for detecting vertical delay vertically coincides with the target position of the image for detecting vertical delay, including: Adjusting the horizontal delay until the image for detecting the vertical delay is located in quadrants 2 and 4, and the illumination intensities of the quadrants 2 and 4 are not zero, or until the image for detecting the vertical delay is located in quadrants 1 and 3, and the illumination intensities of the quadrants 1 and 3 are not zero; If the target position of the image for detecting vertical delay is located at the bottom of quadrant 1 or quadrant 2, each time the vertical delay is adjusted, it is determined whether the light intensity of quadrant 1 or quadrant 2 reaches a maximum value, and whether the corresponding light intensity of quadrant 3 or quadrant 4 is 0; if so, it is determined that the actual position of the image for detecting vertical delay on the QPD vertically coincides with the target position of the image for detecting vertical delay; If the target position of the image for detecting vertical delay is located at the top of the 3rd or 4th quadrant, each time the vertical delay is adjusted, it is determined whether the corresponding light intensity of the 1st or 2nd quadrant is 0, and whether the light intensity of the 3rd or 4th quadrant reaches the maximum value; if so, it is determined that the actual position of the image for detecting vertical delay on the QPD vertically coincides with the target position of the image for detecting vertical delay.

9. The method according to claim 8, wherein The grayscale of the image for detecting vertical delay gradually increases or decreases from top to bottom; the method further includes: During the process of adjusting the vertical delay, the QPD is controlled to collect and calculate the change in the light intensity of the detection image in quadrant 1 or quadrant 3, or the change in the light intensity in quadrant 2 or quadrant 4 is calculated, and whether the adjustment direction of the vertical delay is correct is determined based on the change in the light intensity and a pre-set judgment rule; if correct, continue to adjust the vertical delay; if incorrect, adjust the vertical delay in the opposite direction.

10. The method according to claim 9, wherein The judgment rules are: If the vertical target position is located at the bottom of quadrant 1 or quadrant 2, and the grayscale of the image for detecting vertical delay gradually increases from top to bottom, then during the process of adjusting the vertical delay, if the change in the light intensity of quadrant 1 or quadrant 2 gradually increases, it is determined that the adjustment direction is correct; If the vertical target position is located at the bottom of quadrant 1 or quadrant 2, and the grayscale of the image for detecting the vertical delay gradually decreases from top to bottom, then during the process of adjusting the vertical delay, if the change in the light intensity of quadrant 1 or quadrant 2 gradually decreases, then it is determined that the adjustment direction is correct; If the vertical target position is located at the top of the three or four quadrants, and the grayscale of the image for detecting the vertical delay gradually increases from top to bottom, then during the process of adjusting the horizontal delay, if the change in the light intensity of the three or four quadrants gradually decreases, it is determined that the adjustment direction is correct; If the vertical target position is located at the top of the 3rd or 4th quadrant, and the grayscale of the image for detecting the vertical delay gradually decreases from top to bottom, then during the process of adjusting the vertical delay, if the change in the light intensity of the 3rd or 4th quadrant gradually increases, it is determined that the adjustment direction is correct.

11. A projection display device, characterized in that: The projection display device includes an image light source, a detection light source, a fiber scanner, a spectrometer, a four-quadrant photodiode QPD and a computer-readable storage medium arranged in sequence along the optical path. The light emitted by the image light source and the detection light source is coupled into the fiber scanner. After the light emitted by the fiber scanner is split by the spectrometer, the light emitted by the detection light source is projected onto the QPD to form a detection image, and the light emitted by the image light source is used to form a projection image. The readable storage medium stores a computer program, and when the computer program is executed by a processor, the processor executes the method described in any one of claims 1 to 10.

Images