Image correction method, correction device and correction system for spliced head-up display equipment, and medium

Abstract

The embodiment of the invention provides an image correction method, an image correction device, an image correction system and a medium for spliced head-up display equipment. The splicing type head-up display equipment comprises a first image generation unit, a second image generation unit and a light splitting element, the correction method comprises the following steps: controlling a laser emitting device to emit a detection light beam from one side of a light splitting element, and enabling a central light spot of the detection light beam to enter a beam combining area of the light splitting element; wherein the first part of the central light spot is guided to the detection device after being transmitted by the light splitting element, reflected by the first image generation unit and reflected by the light splitting element in sequence; a second part of the central light spot is guided to the same detection device after being reflected by the light splitting element, reflected by the second image generation unit and transmitted by the light splitting element in sequence; controlling the detection device to collect light spot images returned by the first image generation unit and the second image generation unit; and determining a splicing error according to the light spot image so as to correct the spliced head-up display device.

Description

Image correction methods, correction devices, correction systems, and media for splicing head-up display devices. Technical Field

[0001] This application relates to the field of optical inspection technology, and more specifically, to an image correction method, correction device, correction system, and medium for a splicing head-up display device. Background Technology

[0002] As head-up displays (HUDs) evolve towards larger fields of view and higher resolutions, the pixel count of a single display chip is no longer sufficient to meet the demands of 8K and even higher resolutions. The industry commonly employs a "stitching optical imaging system" as an alternative: the sub-images generated by two 4K×2K TFT, LCoS, or DMD chips are confocally stitched together on the same imaging plane using a beam splitter to obtain a complete 4K×4K image. Theoretically, this solution can double the image size without increasing the pixel density of a single chip.

[0003] However, in actual assembly and adjustment, it was found that any slight deviation in the six degrees of freedom (X, Y, Z translation and rotation around the X, Y, Z axes) of the two optical paths would cause gaps, overlaps, or sudden changes in brightness at the splicing point, i.e., the "seamless splicing" would fail. Existing technologies mainly rely on manual observation or repeated mechanical adjustments using offline projected scales. Manual or visual scales can only make qualitative judgments and cannot simultaneously quantify the six degrees of freedom errors. Furthermore, the adjustment process requires repeated disassembly and reassembly of the optical engine, which is inefficient, costly, and unsuitable for mass production.

[0004] In view of this, a new technical solution is needed to solve the above-mentioned technical problems. Summary of the Invention

[0005] One objective of this application is to provide a new technical solution for image correction in splicing head-up display devices.

[0006] According to a first aspect of this application, an image correction method for a splicing head-up display device is provided.

[0007] The splicing head-up display device includes: a first image generating unit arranged along a first optical path; a second image generating unit arranged along a second optical path; and a beam splitter element disposed at the intersection of the first and second optical paths for combining light rays from the first and second image generating units to form a spliced ​​image on a predetermined imaging surface. The correction method includes the following steps: controlling a laser emitting device to emit a detection beam from one side of the beam splitter element, and causing the central spot of the detection beam to be incident on the beam combining area of ​​the beam splitter element; wherein, a first part of the central spot is sequentially transmitted through the beam splitter element, reflected by the first image generating unit, and reflected again by the beam splitter element, and then guided to a detection device; a second part of the central spot is sequentially reflected by the beam splitter element, reflected again by the second image generating unit, and transmitted through the beam splitter element, and then guided to the same detection device; controlling the detection device to acquire spot images returned by the first and second image generating units; and determining the splicing error based on the spot images to correct the splicing head-up display device.

[0008] Optionally, the first image generation unit has a first glass cover covering its display area; the second image generation unit has a second glass cover covering its display area; wherein controlling the laser emitting device to emit a detection beam from one side of the beam splitter and to incident the central spot of the detection beam onto the beam combining area of ​​the beam splitter specifically includes: controlling the laser emitting device to irradiate a first edge of the first glass cover with a first portion of the central spot, and to irradiate a second edge of the second glass cover with a second portion of the central spot, wherein the first edge and the second edge correspond to a stitching position in the spot image.

[0009] Optionally, determining the stitching error based on the spot image specifically includes: analyzing the relative positional deviation of the stitched image formed by the first image generation unit and the second image generation unit on the predetermined imaging surface based on the spot image, so as to determine the stitching error.

[0010] Optionally, determining the stitching error based on the spot image further includes: comparing the splitting, interference, diffraction, or edge protrusion morphological features presented in the spot image with the pre-calibrated six-degree-of-freedom stitching error-morphological feature correspondence, and directly calculating the translation error and rotation error between the two image generation units in the X, Y, and Z directions.

[0011] Optionally, determining the splicing error based on the light spot image to correct the splicing head-up display device specifically includes: adjusting the relative spatial position between the first image generation unit and the second image generation unit; or performing geometric transformation processing on the original image data pre-stored in the splicing head-up display device to compensate for the splicing error.

[0012] Optionally, the geometric transformation process includes one or more of translation, rotation, scaling, or distortion correction.

[0013] Optionally, the beam-splitting element is a semi-transparent and semi-reflective mirror.

[0014] According to a second aspect of this application, an image correction device for a splicing head-up display device is provided. The correction device includes: a first control module that controls a laser emitting device to emit a detection beam from one side of a beam splitter, and causes the central spot of the detection beam to be incident on the beam combining region of the beam splitter; wherein a first portion of the central spot is sequentially transmitted through the beam splitter, reflected by a first image generating unit, and reflected again by the beam splitter before being guided to the detection device; a second portion of the central spot is sequentially reflected by the beam splitter, reflected by a second image generating unit, and transmitted through the beam splitter before being guided to the same detection device; a second control module that controls the detection device to acquire spot images returned by the first and second image generating units; and a determination module that determines the splicing error based on the spot images to correct the splicing head-up display device.

[0015] According to a third aspect of this application, an image correction system for a video wall head-up display (HUD) device is provided. The correction system includes: a laser emitting device disposed on one side of a beam splitter element of the HUD device, the laser emitting device emitting a detection beam such that its central spot is incident on the beam combining region of the beam splitter element; the laser emitting device includes: a laser and a beam expander arranged sequentially along the transmission direction of the detection beam.

[0016] A detection device is disposed on a predetermined imaging surface of the splicing head-up display device, the detection device being used to acquire spot images returned by the first image generation unit and the second image generation unit.

[0017] According to a fourth aspect of this application, an image correction device for a video wall head-up display (HUD) is provided. The correction device includes the correction apparatus as described in the second aspect; or, the correction device includes a memory and a processor, the memory storing computer instructions, and the processor retrieving the computer instructions from the memory to execute the image correction method for the HUD as described in the first aspect.

[0018] According to a fourth aspect of this application, a computer-readable storage medium is provided. A computer program is stored thereon, which, when executed by a processor, implements the image correction method for a video wall head-up display device according to the first aspect.

[0019] This application provides an image correction method for a splicing head-up display (HUD) device. By controlling a laser emitting device to emit a detection beam and using a beam splitter to guide the light spot back to the detection device via different paths, the acquired light spot image reflects the splicing state of the first and second image generation units. Based on this, the splicing error is determined and corrected, effectively eliminating splicing gaps and image misalignment caused by positional deviations between the two image generation units in the splicing HUD device. This makes the spliced ​​image visually form a complete and coherent whole, greatly improving the overall sense and integrity of the image. Furthermore, in determining the splicing error, the differences in brightness, color, and other aspects between the two image generation units can be comprehensively detected. By correcting these errors, the images displayed by the two units can have more natural and smooth brightness transitions and color connections, avoiding abrupt brightness changes and color banding, presenting users with a uniform and consistent high-quality display image and enhancing the visual experience.

[0020] Other features and advantages of this specification will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0021] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of this specification and, together with their description, serve to explain the principles of this specification.

[0022] Figure 1 shows a partial optical architecture diagram of the splicing head-up display device provided in an embodiment of this application.

[0023] Figure 2 is a flowchart of an image correction method for a splicing head-up display device provided in an embodiment of this application.

[0024] Figure 3 shows a structural block diagram of an image correction device for a splicing head-up display device provided in an embodiment of this application.

[0025] Figure 4 shows an optical architecture diagram for calibrating a splicing head-up display device provided in an embodiment of this application.

[0026] Figures 5 and 6 are schematic diagrams of the morphology of the light spot image and the corresponding error provided in the embodiments of this application.

[0027] Figure 7 is a schematic diagram of geometric transformation processing of the original image provided in an embodiment of this application.

[0028] Figure 8 shows a structural block diagram of an image correction device for a splicing head-up display device provided in an embodiment of this application. Detailed Implementation

[0029] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0030] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0031] Technologies and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such technologies and equipment should be considered part of the specification.

[0032] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0033] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0034] Figure 1 is a partial hardware structure diagram of a splicing head-up display device according to an embodiment of this application. Referring to Figure 1, the splicing head-up display device includes: a first image generation unit 101 arranged along a first optical path; a second image generation unit 102 arranged along a second optical path; and a beam splitter 103 disposed at the intersection of the first and second optical paths, for combining the light rays from the first image generation unit 101 and the second image generation unit 102 to form a spliced ​​image on a predetermined imaging surface.

[0035] In this embodiment, the splicing head-up display device includes a first image generation unit 101, which is disposed in the first optical path and used to emit a first sub-image beam. The first image generation unit 101 is responsible for generating a portion of the image content (i.e., a portion of the pattern of the image displayed in the head-up display device). The first image generation unit 101 can be various types of image generation devices, including liquid crystal display devices (LCDs), organic light-emitting diode display devices (OLEDs), digital micromirror devices (DMDs), TFTs, or other display devices, to generate image signals with specific patterns, colors, and brightness, and to emit these signals as light along the first optical path.

[0036] The splicing head-up display device includes a second image generation unit 102, which is disposed in the second optical path and used to emit a second sub-image beam. The second image generation unit 102 generates another part of the image content (i.e., another part of the pattern of the image displayed in the head-up display device). Various image generation technologies can be used, and the images generated may differ from those generated by the first image generation unit 101 in terms of content, color, and brightness, or they may complement each other to form a complete spliced ​​image.

[0037] The beam splitter 103 is located at the intersection of the first optical path and the second optical path. That is, the beam splitter 103 is located at the intersection of the light propagation paths and can simultaneously receive light from the first image generation unit 101 and the second image generation unit 102.

[0038] Beam splitter 103 performs beam combining operation on light rays from two image generation units. Beam splitter 103 has optical properties of partial transmission and partial reflection. Beam splitter 103 can reflect the light rays emitted by the first image generation unit 101 and transmit the light rays emitted by the second image generation unit 102, so that the two beams of light can be combined together in a predetermined manner after passing through beam splitter 103, and finally form a stitched image on a predetermined imaging surface.

[0039] The specific type of the beam-splitting element 103 can be a beam splitter. For example, the beam-splitting element 103 can be a semi-transparent and semi-reflective mirror.

[0040] The predetermined imaging surface can have various possible configurations. It can be a specific screen for directly displaying the stitched image; it can be the location of the observer's eyes for direct viewing of the image; or it can be any other location selected based on actual display needs. Taking a head-up display (HUD) as an example, in such devices, the predetermined imaging surface can be set at the location where a reflective amplification element is configured (e.g., the location of a small reflector for the reflective amplification element). Through the effect of the reflective amplification element on light, the image can be presented to the observer at an appropriate location with suitable size and brightness.

[0041] It is important to emphasize that in the splicing head-up display device provided in this application, the beam splitter 103 is preferably a beam splitter rather than a polarizing beam splitter plate, thereby reducing the risk of stray light introduced by inserting additional polarizing elements. Furthermore, the beam splitter does not adjust the polarization state of the light during operation. Based on this characteristic, the beams output by the first image generation unit 101 and the second image generation unit 102, after splicing, form a non-polarized image. When the light from the entire spliced ​​image enters the human eye after being reflected by the windshield, the absence of uneven brightness due to polarization state differences ensures uniform overall image brightness, significantly improving image brightness consistency and providing users with a superior visual experience.

[0042] In the above description, those skilled in the art can design instructions based on the scheme disclosed in this application. How the instructions control the processor to operate is well known in the art, and therefore will not be described in detail here.

[0043] This application provides an image correction method for a splicing head-up display (HUD) device. This correction method can quickly, easily, and accurately detect splicing errors between two image generation units, effectively improving the image display quality and splicing accuracy of the splicing HUD device. Furthermore, this method does not require disassembling the optical engine, allowing for rapid and accurate splicing error detection and compensation while the splicing HUD device is still in production line condition before leaving the factory.

[0044] Referring to Figure 2, the image correction method for a splicing head-up display device includes: S201: controlling the laser emitting device 400 to emit a detection beam from one side of the beam splitter 103, and causing the central spot of the detection beam to be incident on the beam combining area of ​​the beam splitter 103; wherein, a first part of the central spot is sequentially transmitted through the beam splitter 103, reflected by the first image generating unit 101, and reflected again by the beam splitter 103, and then guided to the detection device; a second part of the central spot is sequentially reflected by the beam splitter 103, reflected by the second image generating unit 102, and transmitted through the beam splitter 103, and then guided to the same detection device; S202: controlling the detection device to acquire the spot images returned by the first image generating unit 101 and the second image generating unit 102; S203: determining the splicing error based on the spot images to correct the splicing head-up display device.

[0045] In this embodiment of the application, referring to the structure of the splicing head-up display device shown in FIG1, it can be seen that the first image generation unit 101 and the second image generation unit 102 are respectively located on both sides of the inclined beam splitter 103. Furthermore, the optical path lengths of the light transmitted by the first image generation unit 101 and the second image generation unit 102 reaching the beam combining region of the beam splitter 103 are consistent.

[0046] In step S201, the laser emitting device 400 is controlled to emit a detection beam from one side of the beam splitter 103. The detection beam emitted by the laser emitting device 400 has the ability to enter the beam combining region of the beam splitter 103. For example, the laser emitting device 400 and the second image generating unit 102 are disposed on the same side of the beam splitter 103, and the detection beam emitted by the laser emitting device 400 can enter the beam combining region of the beam splitter 103.

[0047] It should be noted that the detection beam emitted by the laser emitting device 400 is projected onto the beam combining area of ​​the beam splitter 103. This beam combining area is the same specific region as the beam combining area of ​​the beam splitter 103 reached by the light rays transmitted from the first image generating unit 101 and the second image generating unit 102. This ensures that after the detection and calibration of the splicing head-up display device is completed, the light rays emitted by the first image generating unit 101 and the second image generating unit 102, when spliced ​​on the preset imaging surface, can present a splicing effect that matches the calibration process, thereby effectively improving the overall display quality and performance stability of the device.

[0048] In this step, the laser emitting device 400 emits a detection beam from one side of the beam splitter 103, and precisely directs the center spot of the detection beam into the beam combining region of the beam splitter 103. This ensures that the first and second optical paths obtain spot images with completely consistent spatial references, eliminating systematic errors introduced by differences in the position of the light source and improving the accuracy of subsequent error calculation. The center spot of the detection beam refers to the spot formed in the region of highest energy concentration and brightness on the cross-section of the detection beam emitted by the laser emitting device 400 during its propagation.

[0049] This can be understood as follows: accurately incidenting the central spot of the detection beam onto this area ensures that the first and second parts of the central spot can propagate along a predetermined path. Specifically, the first part of the central spot is sequentially transmitted through the beam splitter 103, reflected by the first image generation unit 101, and then reflected again by the beam splitter 103 before being guided to the detection device. Referring to Figure 4, the image on the right side of the spot image is the spot image returned to the detection device by the first image generation unit 101.

[0050] The second part, after being reflected by the beam splitter 103, reflected by the second image generation unit 102, and transmitted through the beam splitter 103, is also guided to the same detection device. Referring to Figure 4, the left image of the spot image is the spot image returned to the detection device by the second image generation unit 102.

[0051] This optical path design enables the detection device to simultaneously acquire spot information from two different image generation units, providing a reliable optical path guarantee for subsequent comprehensive and accurate analysis of stitching errors. If the central spot is not incident on the beam combining region, it may lead to optical path chaos, making it impossible to achieve the expected acquisition of two spot paths, thereby affecting the accuracy of stitching error detection.

[0052] Furthermore, by incidenting the central spot of the detection beam onto the beam combining region, the two parts of the spot reach the same detection device after passing through different transmission-reflection paths. This design enables comprehensive detection of stitching errors between the two image generation units, improving the comprehensiveness and accuracy of stitching error detection. Simultaneously, the central spot, after passing through the beam splitter 103, forms a dual transmission-reflection path, which is coupled to the two image generation units respectively. This allows for simultaneous sampling of two return paths with a single illumination, thus shortening the detection time.

[0053] In this embodiment, the detection beam emitted by the laser emitting device 400 has high directionality and monochromaticity, enabling the formation of a clear and accurate central spot. By controlling the spot to be incident on the beam combining region of the beam splitter 103 and guiding it back to the detection device via a specific path, the acquired spot image contains stitching error information. Analyzing this information using image processing algorithms allows for the calculation of errors in translation and rotation between the two image generation units, providing a reliable basis for subsequent high-precision correction.

[0054] In a further embodiment, the first image generation unit 101 has a first glass cover covering its display area; the second image generation unit 102 has a second glass cover covering its display area; wherein controlling the laser emitting device 400 to emit a detection beam from one side of the beam splitter 103 and to cause the central spot of the detection beam to be incident on the beam combining area of ​​the beam splitter 103 specifically includes: controlling the laser emitting device 400 to cause a first part of the central spot to irradiate a first edge of the first glass cover, and a second part of the central spot to irradiate a second edge of the second glass cover, wherein the first edge and the second edge correspond to a stitching position in the spot image.

[0055] Referring to Figure 4, when the intensity of the light emitted from the laser emitting device 400 is strong, the surrounding edge areas of the first and second glass covers are displayed. In Figure 4, component 1011 is an image of the first glass cover, component 1021 is an image of the second glass cover, and the light spot image is located at the junction area of ​​the first and second glass covers.

[0056] In this embodiment, the first edge of the first glass cover and the second edge of the second glass cover correspond to the edge positions of the display areas of their respective image generation units. The first edge and the second edge constitute the physical seam of the subsequent stitched image. When the light spot image simultaneously covers the first edge of the first glass cover and the second edge of the second glass cover, this is equivalent to performing an in-situ sampling operation on the "seam line". Compared to sampling within the display area, this method can effectively avoid the pixel aliasing problem introduced by sampling, so that the measurement results can completely match the visually observed seam situation.

[0057] Furthermore, the morphological changes of the edge light spot exhibit a monotonic correspondence with the errors in the six degrees of freedom. This characteristic ensures that the light emitted from the first image generation unit 101 and the second image generation unit 102, when stitched together on a pre-defined imaging surface, produces a stitching effect consistent with the correction process. Ultimately, this significantly improves the overall display quality and performance stability of the spliced ​​head-up display device.

[0058] It should be noted that after the positional calibration of the first edge of the first glass cover and the second edge of the second glass cover is completed, since the pixel positions of the first image generation unit 101 and the second image generation unit 102 are fixed at the factory, and the relative positional relationship between these two image generation units and the first edge of the first glass cover and the second edge of the second glass cover is also fixed, when the seam formed by the first edge of the first glass cover and the second edge of the second glass cover is ensured to achieve good splicing effect, the light emitted by the first image generation unit 101 and the second image generation unit 102, when spliced ​​on the pre-set imaging surface, can present a splicing effect that is completely consistent with the calibration process. Simply put, after the adjacent edge positions of the first and second glass covers are calibrated, since the relative positions of the pixel arrays of the two image generation units and their respective cover edges are fixed at the factory, as long as the cover edge splicing meets the alignment criteria, it can be ensured that the beams emitted by the two units achieve pixel-level seamless splicing on the predetermined imaging surface, without the need for secondary compensation of the display pixels.

[0059] In step S202, the circular central light spot emitted from the laser emitting device 400 is split by the beam splitter 103, and half of the light spot outline is reflected by the first image generation unit 101 and the second image generation unit 102, respectively. The two halves of the outline are recombined into a complete circular light spot in the beam combining area of ​​the beam splitter 103 and continue to be transmitted to the detection device located on the predetermined imaging surface. The stitching gap in the composite light spot image acquired by the detection device, that is, the physical stitching between the first edge of the first glass cover and the second edge of the second glass cover mentioned above, is used to directly evaluate the relative alignment status of the two image generation units.

[0060] For example, the detection device includes, but is not limited to, a CCD, a CMOS camera, or other image sensors with imaging capabilities.

[0061] In step S203, the principle behind determining the stitching error based on the spot image acquired in step S202 is that there is a close correlation between the morphological features of the spot image and the stitching state of the image generation unit.

[0062] Specifically, any deviation in the horizontal or vertical displacement of the image generation unit, or any angular rotation deviation, will significantly affect the morphology of the light spot image. Once an error occurs during the stitching process, the light spot image will no longer present the ideal morphology, but will undergo a series of changes such as shape distortion, positional shift, and uneven brightness distribution. By analyzing these changes and using pre-established optical models and mathematical algorithms, the specific value and direction of the stitching error can be accurately deduced, such as determining the horizontal and vertical offset of the image generation unit and its rotation angle.

[0063] After analyzing the splicing errors, targeted correction operations are performed on the splicing head-up display device based on these error data. By adjusting parameters such as the position and angle of the image generation unit, or optimizing other related components in the optical system (such as optimizing the pixel position of the original image), the splicing errors are compensated, enabling the splicing head-up display device to present a high-quality, seamless image effect.

[0064] In one specific embodiment, the splicing error type can be determined through image feature extraction, error calculation model establishment, error determination and classification.

[0065] Image feature extraction: Image processing algorithms are used to extract features from the acquired light spot image. For example, features such as the edge contour, center position, and area of ​​the light spot can be extracted. For circular light spot images, if the stitching is correct, the combined light spot should be a complete and symmetrical circle; if there is a stitching error, the light spot may be deformed or shifted, and its edge contour will become irregular.

[0066] Error Feature Model (Preset Six-DOF Error-Shape Feature Model): Based on the optical principles and geometric relationships of the splicing head-up display device, an error calculation model is established. This model establishes a mathematical relationship between the extracted spot image features and the actual splicing error parameters (such as angle error, displacement error, etc.). By inputting the spot image feature values, the model can output the corresponding splicing error values. For example, based on the offset of the spot center position and combined with the parameters of the optical system, the displacement error of the image generation unit in the horizontal or vertical direction can be calculated.

[0067] Error Determination and Classification: Based on the output of the error calculation model, the specific type and magnitude of the stitching error are determined. Stitching errors may include translation errors (positional offset of image generation units in the horizontal or vertical direction), rotation errors (rotational angle deviation of image generation units around a certain axis), etc. Accurate classification and quantification of different types of errors helps in taking targeted corrective measures subsequently.

[0068] In step S203, further, determining the stitching error based on the spot image specifically includes: analyzing the relative positional deviation of the stitched image formed by the first image generation unit 101 and the second image generation unit 102 on the predetermined imaging surface based on the spot image, so as to determine the stitching error.

[0069] In this embodiment, the morphological features of the light spot image are analyzed based on the fixed projection position of the detection beam in the beam combining region of the beam splitter 103, and the spatial correspondence between the splicing seam and the first edge of the first glass cover plate and the second edge of the second glass cover plate in the light spot image. These morphological features include at least edge offset, interference fringe density, diffraction fringe spacing, and edge protrusion direction.

[0070] The obtained morphological features are compared with a pre-defined six-degree-of-freedom error-error feature model. Through this comparison, the relative positional deviation between the first image generation unit 101 and the second image generation unit 102 on the predetermined imaging surface can be directly calculated, thus yielding the specific value of the stitching error. In this embodiment, utilizing the light reflection characteristics of the first edge of the first glass cover and the second edge of the second glass cover provides higher response sensitivity to six-degree-of-freedom deviations compared to the reflection of light by in-plane pixels. Specifically, this edge reflection method can convert sub-micron level displacement into precisely measurable stripe changes or offsets, thereby effectively amplifying the error signal for more accurate determination of the stitching error.

[0071] In step S203, further, determining the stitching error based on the spot image specifically includes: comparing the splitting, interference, diffraction, or edge protrusion morphological features presented in the spot image with the pre-calibrated six-degree-of-freedom stitching error-morphological feature correspondence, and directly calculating the translation error and rotation error around the X, Y, and Z axes between the two image generation units in the X, Y, and Z directions.

[0072] In this embodiment, the same light spot can provide four types of features based on its projection position: edge offset, interference fringe density, diffraction fringe spacing, and edge protrusion direction. These features are mapped to X / Y / Z translation and X / Y / Z rotation, respectively. This eliminates the need for multi-pose scanning and completes six-degree-of-freedom error separation in a single frame, thus shortening the detection time.

[0073] In a specific embodiment, both the first image generation unit 101 and the second image generation unit 102 are TFT screens. For the case of two TFT screens being spliced ​​together, there is a specific correspondence between the splicing error and the shape of the light spot image, as follows: In an ideal state, i.e., when there is no error in the splicing of the two TFT screens, the light spot image obtained by the detection device appears circular, and the brightness, size, and other characteristics of the light spot are uniform and consistent, as shown in Figure 5(a).

[0074] However, when there are translational errors in the x, y, and z directions and rotational errors around the x, y, and z axes between the two TFT screens, obvious phenomena such as image splitting and interference fringes will appear. These phenomena can be clearly observed with a camera. The correspondence between the errors of each degree of freedom and the image morphology of the spot is shown in Figures 5(b)-5(f): x-direction related error: Referring to Figure 5(b), positive x-direction translational error and rotational error around the z-axis: When there are positive x-direction translational errors and rotational errors around the z-axis during splicing, the displayed images of the two TFT screens will move away from each other. At this time, the image will split into two independent spots, and the distance between the spots is related to the amount of translational error or rotational error, that is, the larger the error, the larger the distance between the spots.

[0075] Referring to Figure 5(c), negative x-axis translation error and rotation error around the z-axis: If there is both negative x-axis translation error and rotation error around the z-axis during splicing, the display areas of the two TFT screens will overlap. Due to the high coherence of the laser, the optical paths of the two beams are close in the overlapping region, thus producing interference fringes. The density of the interference fringes is related to the rotation error between the TFT screens; the larger the rotation error, the denser the interference fringes. The size of the fringe area is related to the translation error; the larger the translation error, the wider the fringe area.

[0076] Y-axis translation error: Referring to Figure 5(d), when there is a y-axis translation error in the stitching, the detection beam will produce a straight-edge Fresnel diffraction phenomenon when passing through the edge of the TFT screen display area. The diffraction fringes can be captured when the detection device (camera) is in defocus. Based on the spacing of these diffraction fringes, the amount of y-axis translation error of the stitched image can be accurately determined; that is, there is a specific correspondence between the diffraction fringe spacing and the amount of y-axis translation error.

[0077] Z-axis correlation error: Referring to Figure 5(e), Z-axis translation error or rotation error around the x-axis: When there is a Z-axis translation error or rotation error around the x-axis in the stitched image, the edges of the light spot image will show bulges. By observing the direction of the bulges, the specific error type and direction can be determined. Y-axis rotation error: Referring to Figure 5(f), when there is a Y-axis rotation error in the stitched image, the image will show a state where some parts are separated and some parts overlap. Reflected on the light spot image, this is manifested as interference fringes in some areas and light spot splitting in other areas. Based on this specific situation of the light spot, the corresponding Y-axis rotation error can be accurately detected.

[0078] It should be noted that when the light emitted by the laser emitting device 400 has a large beam expansion effect and the light intensity is at a strong level, the four edges of the first glass cover plate of the first image generating unit 101 and the four edges of the second glass cover plate of the second image generating unit 102 can be clearly presented, thereby forming the images shown in Figures 6(a)-6(f), and the light spot image is located in the boundary area between the image 1011 presented by the first glass cover plate and the image 1012 presented by the second glass cover plate.

[0079] Based on the preceding analysis of the relationship between the light spot image and the splicing error, it is known that after acquiring the light spot image of the splicing head-up display device, the morphological features such as splitting, interference, diffraction, or edge protrusion can be precisely compared with the pre-determined six-degree-of-freedom splicing error-morphological feature correspondence, derived experimentally or theoretically. This comparison allows for the direct calculation of the specific translational errors between the two image generation units in the X, Y, and Z directions, as well as the specific rotational errors around the X, Y, and Z axes. Based on the precise error data obtained from the aforementioned error-free analysis, the splicing head-up display device can be accurately calibrated, thereby achieving the goal of effectively correcting splicing errors.

[0080] In step S203, determining the splicing error based on the light spot image to correct the splicing head-up display device specifically includes: adjusting the relative spatial position between the first image generation unit 101 and the second image generation unit 102; or performing geometric transformation processing on the original image data pre-stored in the splicing head-up display device to compensate for the splicing error. The geometric transformation processing includes one or more of translation, rotation, scaling, or distortion correction.

[0081] In this embodiment, the technical solution of determining splicing errors and correcting splicing head-up display devices based on light spot images, through two different correction methods, can significantly improve the display quality and performance of splicing head-up display devices, bringing users a better user experience.

[0082] Specifically, by adjusting the relative spatial position between the first image generation unit 101 and the second image generation unit 102, splicing errors caused by factors such as inaccurate physical installation and mechanical deformation can be directly corrected. For example, y-translation and rotation can be corrected by adjusting the relative spatial position between the first image generation unit 101 and the second image generation unit 102.

[0083] In one specific embodiment, if the spot image shows a misalignment between two image generation units in the y-direction, fine-tuning the position of one of the units can perfectly align the display areas of the two units, eliminating the seam in the y-direction and achieving seamless splicing, thus improving the overall look and integrity of the image. Furthermore, adjusting the relative spatial position not only eliminates the seam but also improves the consistency of the two image generation units in terms of brightness and color. During the adjustment process, the brightness distribution and color difference information reflected in the spot image can be comprehensively considered to optimize the position and angle of the units, making the brightness transition and color connection of the images displayed by the two units more natural and smooth. This avoids abrupt brightness changes and color banding caused by splicing errors, presenting users with a more uniform and consistent display.

[0084] By performing geometric transformations on the raw image data pre-stored in the splicing head-up display device, high flexibility is achieved. Regardless of the cause, magnitude, or direction of the splicing error, appropriate geometric transformation algorithms, such as translation, rotation, and scaling, can be selected to adjust the raw image data accordingly and compensate for the error. For example, when a rotation error is detected between two image generation units, the raw images can be rotated in the opposite direction to ensure that the images displayed by the two units maintain the same angle, achieving accurate splicing. Furthermore, software-based geometric transformation processing enables real-time correction, quickly calculating the required geometric transformation parameters based on real-time acquired spot image information and immediately processing and updating the raw image data. In addition, compared to adjusting the physical position of the image generation units, this adjustment method does not require complex mechanical structures and precise adjustment devices. Only the corresponding algorithm modules need to be integrated into the device's software system, reducing hardware costs and complexity, decreasing the device's size and weight, and improving its portability and integrability. Meanwhile, software algorithms are relatively easy to upgrade and optimize. The correction effect and performance can be continuously improved through software updates, which provides convenience for the long-term use and functional expansion of the equipment.

[0085] Referring to Figure 7, after completing the error detection operation, software cropping can be used to correct the x-translation and rotation errors, as well as the z-translation and rotation errors. The principle of software cropping correction is shown in Figure 7: Figure 7a is the original image, which is stitched together to form Figure 7b, where stitching errors exist. Based on the stitching errors, the original image is corrected to form Figure 7c. After stitching, the corrected images form a seamless image.

[0086] Specifically, during the stitching process, the two TFT screens are brought close together, resulting in overlapping pixel areas between them. When the camera detects translational and rotational errors in the stitching, the number of overlapping pixel columns can be accurately calculated by dividing the size of the acquired interference fringes by the size of a single TFT pixel. When the software renders the user interface (UI) image, the overlapping pixels on the TFT2 screen are cropped, and the image within the overlapping area is moved laterally to move it out of the overlapping region. After these operations, the stitched image from the two image generation units is a complete and intact image.

[0087] In this embodiment, by controlling the laser emitting device 400 to emit a detection beam and using the beam splitter 103 to guide the light spot back to the detection device via different paths, the acquired light spot image can reflect the splicing state of the first image generation unit 101 and the second image generation unit 102. Based on this, the splicing error is determined and corrected, which can effectively eliminate the splicing gaps and image misalignment problems caused by the positional deviation of the two image generation units in the spliced ​​head-up display device, making the spliced ​​image visually form a complete and coherent whole, greatly improving the overall sense and integrity of the picture. In addition, in the process of determining the splicing error, the differences in brightness, color, and other aspects between the two image generation units can be comprehensively detected. By correcting these errors, the images displayed by the two units can be made to have a more natural and smooth transition in brightness and color, avoiding sudden changes in brightness and color banding, presenting users with a uniform and consistent high-quality display picture, and enhancing the visual experience.

[0088] This application embodiment also provides an image correction device for a splicing head-up display device. Referring to FIG3, the image correction device for a splicing head-up display device includes: a first control module 301, which controls a laser emitting device 400 to emit a detection beam from one side of the beam splitter 103, and causes the central spot of the detection beam to be incident on the beam combining area of ​​the beam splitter 103; wherein, a first part of the central spot is sequentially transmitted through the beam splitter 103, reflected by the first image generating unit 101, and reflected again by the beam splitter 103, and then guided to the detection device; a second part of the central spot is sequentially reflected by the beam splitter 103, reflected by the second image generating unit 102, and transmitted through the beam splitter 103, and then guided to the same detection device; a second control module 302, which controls the detection device to acquire the spot images returned by the first image generating unit 101 and the second image generating unit 102; and a determination module 303, which determines the splicing error based on the spot images to correct the splicing head-up display device.

[0089] This application provides an image correction device for a splicing head-up display (HUD) device. This correction device controls a laser emitting device 400 to emit a detection beam, and uses a beam splitter 103 to guide the light spot back to the detection device via different paths. The acquired light spot image reflects the splicing state of the first image generation unit 101 and the second image generation unit 102. Based on this, the splicing error is determined and corrected, effectively eliminating splicing gaps and image misalignment caused by positional deviations between the two image generation units in the splicing HUD device. This makes the spliced ​​image visually form a complete and coherent whole, greatly improving the overall sense and integrity of the image. Furthermore, in determining the splicing error, the differences in brightness, color, and other aspects between the two image generation units can be comprehensively detected. By correcting these errors, the images displayed by the two units can have more natural and smooth brightness transitions and color connections, avoiding sudden brightness changes and color banding, presenting users with a uniform and consistent high-quality display image, and enhancing the visual experience.

[0090] According to the image correction device for a splicing head-up display device provided in the embodiments of this application, the first control device 301 is specifically used to control the laser emitting device 400 to make the first part of the central light spot irradiate the first edge of the first glass cover plate, and the second part of the central light spot irradiate the second edge of the second glass cover plate, and the first edge and the second edge correspond to the splicing position in the light spot image.

[0091] According to the image correction device for a splicing head-up display device provided in the embodiments of this application, the determining module 302 is specifically used to analyze the relative position deviation of the splicing image formed by the first image generation unit 101 and the second image generation unit 102 on the predetermined imaging surface based on the light spot image, so as to determine the splicing error.

[0092] According to the image correction device for splicing head-up display device provided in the embodiments of this application, the determining module 302 is further specifically used to compare the splitting, interference, diffraction or edge protrusion morphological features presented in the light spot image with the pre-calibrated six-degree-of-freedom splicing error-morphological feature correspondence, and directly calculate the translation error and rotation error around the X, Y, and Z axes between the two image generation units in the X, Y, and Z directions.

[0093] This application also provides an image correction system for a splicing head-up display device. Referring to FIG4, the correction system includes: a laser emitting device 400 disposed on one side of the beam splitter 103 of the splicing head-up display device, the laser emitting device 400 being used to emit a detection beam so that its central spot is incident on the beam combining region of the beam splitter 103; and a detection device disposed on a predetermined imaging surface of the splicing head-up display device, the detection device being used to acquire the spot image returned by the first image generation unit 101 and the second image generation unit 102.

[0094] In this embodiment, the laser emitting device 400 is disposed on one side of the beam splitting element 103 of the splicing head-up display device, and can emit a detection beam with high directionality and monochromaticity to ensure that the central light spot is incident on the beam combining area of ​​the beam splitting element. This light spot positioning method lays the foundation for subsequent error detection, enabling the acquired light spot image to accurately reflect the splicing state of the first image generation unit 101 and the second image generation unit 102. By analyzing the light spot image, the splicing errors of the two units in terms of translation, rotation, etc., can be calculated, providing a reliable basis for correction operations, thereby effectively eliminating gaps, misalignments, and other problems in the spliced ​​image, significantly improving the display quality of the splicing head-up display device, and presenting users with a clear, complete, and coherent visual image.

[0095] In this embodiment, the detection device is positioned on a predetermined imaging surface and can acquire the spot images returned by the first and second image generation units 102. These spot images contain information reflecting not only the spatial positional deviation between the two units but also potential differences in brightness, color, and other aspects. By integrating this information, a comprehensive understanding of the specific splicing error can be achieved, allowing for targeted correction measures to ensure smoother and more natural transitions in brightness and color, thereby further improving display consistency and uniformity.

[0096] In one specific embodiment, the laser emitting device 400 includes a laser 401 and a beam expander 402 arranged sequentially along the transmission direction of the detection beam.

[0097] In this embodiment, laser 401 is the light source of the entire laser emitting device 400, and it is capable of generating a laser beam with high directionality, high monochromaticity, and high coherence. This laser beam has the characteristics of concentrated energy and precise direction, providing a stable and reliable light source basis for subsequent error detection.

[0098] The main function of the beam expander 402 is to increase the diameter of the laser beam output by the laser 401 by a certain factor. By increasing the beam diameter, the divergence angle of the beam can be reduced, making the detection beam more focused during transmission, reducing energy loss, and improving the beam's propagation distance and accuracy.

[0099] This application also provides an image correction device for a splicing head-up display device. Referring to FIG8 or FIG3, the correction device includes the correction apparatus as described above; or, the correction device includes: a memory and a processor, wherein the memory is used to store computer instructions, and the processor is used to call the computer instructions from the memory to execute the image correction method for the splicing head-up display device as described above.

[0100] This application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any of the image correction methods for a splicing head-up display device provided in the above-described method embodiments.

[0101] This application may be a system, method, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of this application.

[0102] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example—but not limited to—electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination of the foregoing. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0103] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0104] The computer program instructions used to perform the operations of this application may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuits, such as programmable logic circuits, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), are personalized by utilizing the status information of the computer-readable program instructions. These electronic circuits can execute the computer-readable program instructions to implement various aspects of this application.

[0105] Various aspects of this application are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0106] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0107] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0108] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction containing one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions. It will be well known to those skilled in the art that implementation in hardware, implementation in software, and implementation using a combination of software and hardware are equivalent.

[0109] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical applications, or technological improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein. The scope of this application is defined by the appended claims.

Claims

1. An image correction method for a splicing head-up display device, characterized in that, The splicing head-up display device includes: a first image generating unit arranged along a first optical path; a second image generating unit arranged along a second optical path; and a beam splitter element disposed at the intersection of the first and second optical paths for combining light rays from the first and second image generating units to form a spliced ​​image on a predetermined imaging surface. The correction method includes the following steps: controlling a laser emitting device to emit a detection beam from one side of the beam splitter element, and causing the central spot of the detection beam to be incident on the beam combining area of ​​the beam splitter element; wherein, a first part of the central spot is sequentially transmitted through the beam splitter element, reflected by the first image generating unit, and reflected again by the beam splitter element, and then guided to a detection device; a second part of the central spot is sequentially reflected by the beam splitter element, reflected again by the second image generating unit, and transmitted through the beam splitter element, and then guided to the same detection device; controlling the detection device to acquire spot images returned by the first and second image generating units; and determining the splicing error based on the spot images to correct the splicing head-up display device.

2. The image correction method for a splicing head-up display device according to claim 1, characterized in that, The first image generation unit has a first glass cover plate covering its display area; the second image generation unit has a second glass cover plate covering its display area; wherein, controlling the laser emitting device to emit a detection beam from one side of the beam splitter and to cause the central spot of the detection beam to be incident on the beam combining area of ​​the beam splitter specifically includes: controlling the laser emitting device to cause a first part of the central spot to irradiate a first edge of the first glass cover plate, and a second part of the central spot to irradiate a second edge of the second glass cover plate, wherein the first edge and the second edge correspond to a stitching position in the spot image.

3. The image correction method for a splicing head-up display device according to claim 2, characterized in that, Determining the stitching error based on the light spot image specifically includes: analyzing the relative positional deviation of the stitched image formed by the first image generation unit and the second image generation unit on the predetermined imaging surface based on the light spot image, so as to determine the stitching error.

4. The image correction method for a splicing head-up display device according to claim 1 or 2, characterized in that, Determining the stitching error based on the light spot image also specifically includes: comparing the splitting, interference, diffraction, or edge protrusion morphological features presented in the light spot image with the pre-calibrated six-degree-of-freedom stitching error-morphological feature correspondence, and directly calculating the translation error and rotation error around the X, Y, and Z axes between the two image generation units in the X, Y, and Z directions.

5. The image correction method for a splicing head-up display device according to claim 1, characterized in that, Determining the splicing error based on the light spot image to correct the splicing head-up display device specifically includes: adjusting the relative spatial position between the first image generation unit and the second image generation unit; or performing geometric transformation processing on the original image data pre-stored in the splicing head-up display device to compensate for the splicing error.

6. The image correction method for a splicing head-up display device according to claim 5, characterized in that, The geometric transformation process includes one or more of translation, rotation, scaling, or distortion correction.

7. The image correction method for a splicing head-up display device according to claim 1, characterized in that, The beam splitter is a semi-transparent, semi-reflective mirror.

8. An image correction device for a splicing head-up display device, characterized in that, The correction device includes: a first control module that controls the laser emitting device to emit a detection beam from one side of the beam splitter, and to cause the central spot of the detection beam to be incident on the beam combining area of ​​the beam splitter; wherein, a first part of the central spot is sequentially transmitted through the beam splitter, reflected by the first image generating unit, and reflected again by the beam splitter before being guided to the detection device; a second part of the central spot is sequentially reflected by the beam splitter, reflected by the second image generating unit, and transmitted through the beam splitter before being guided to the same detection device; a second control module that controls the detection device to acquire the spot images returned by the first image generating unit and the second image generating unit; and a determination module that determines the splicing error based on the spot images to correct the spliced ​​head-up display device.

9. An image correction system for a splicing head-up display device, characterized in that, The correction system includes: a laser emitting device disposed on one side of the beam splitter of the splicing head-up display device, the laser emitting device being used to emit a detection beam so that its central spot is incident on the beam combining region of the beam splitter; the laser emitting device includes: a laser and a beam expander arranged sequentially along the transmission direction of the detection beam; and a detection device disposed on a predetermined imaging surface of the splicing head-up display device, the detection device being used to acquire the spot image returned by the first image generation unit and the second image generation unit.

10. An image correction device for a splicing head-up display device, characterized in that, The correction device includes the correction apparatus as described in claim 8; or, the correction device includes: a memory and a processor, the memory for storing computer instructions, and the processor for calling the computer instructions from the memory to execute the image correction method for a splicing head-up display device as described in any one of claims 1-7.

11. A computer-readable storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the image correction method for a splicing head-up display device according to any one of claims 1-7.

Images