Pixel density enhancement system based on double static modules and light pattern projection method
By using a pixel density enhancement system with dual stationary modules in automotive projection headlights, the problem of insufficient pixel density is solved by staggered and overlapping light pattern images, achieving high-precision light pattern control and cost reduction.
Patent Information
- Application Number
- CN202511643412.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-11
- Publication Date
- 2026-02-06
AI Technical Summary
The existing microdisplay chips in automotive projection headlights have large pixel sizes, resulting in insufficient pixel density, jagged edges and screen-door effects, and making it difficult to achieve complex light pattern control.
A pixel density enhancement system based on dual static modules is adopted. By interleaving two identical projection modules with a horizontal and vertical offset of 0.5 pixels respectively, the projected light pattern images are superimposed to increase the pixel density to nearly 4 times.
It significantly eliminates the sawtooth and screen-door effects, improves light pattern control accuracy, reduces hardware costs and power consumption, and has high system reliability, making it suitable for automotive adaptive headlights and digital headlights.
Smart Images
Figure CN121477538A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of lighting technology, and in particular to a micro-display projection system in automotive adaptive headlights (ADB) or digital headlights, aiming to improve the effective pixel density of the projected light pattern without changing the physical size of the existing light source and chip. Background Technology
[0002] Traditional automotive projection headlights use microdisplay chips such as microLEDs to generate pixelated light patterns. They employ simple overlay of patterns from one or two projection modules to project simple road surface images such as vehicle speed limits, weather, and lane markings. Figure 1 As shown in the diagram, a conventional vehicle headlight projection module includes a projection lens 10 and a light source or image source 20; as Figure 2 The traditional automotive headlight projection module application scenario 1 shown includes projection module A30 and projection module B40, both integrated inside the automotive headlight assembly and driven by a central controller. Projection module A30 forms output pattern 1, and projection module B40 forms output pattern 2. A partial field-of-view superposition pattern is formed between output pattern 1 and output pattern 2; as shown... Figure 3 The traditional automotive headlight projection module application scenario 2 shown includes projection module A30 and projection module B40, both integrated inside the automotive headlight assembly and driven by a central controller. Projection module A30 forms output pattern 1, and projection module B40 forms output pattern 2. Output pattern 1 and output pattern 2 form a completely superimposed pattern. However, due to limitations in chip manufacturing processes and costs, the physical pixel size of these chips is relatively large, leading to the following situation:
[0003] 1. Insufficient pixel density: The resolution of the projected light pattern is limited by the number of pixels in the chip itself (e.g., 320*80), making it difficult to achieve complex and fine pixel-level light pattern control.
[0004] 2. Aliasing Effect: Larger pixel boundaries indicate pixel jumps when there are bevels.
[0005] 3. Screen Door Effect: Larger pixel gaps are clearly visible at the edge of the light pattern or during near-field projection, affecting the quality and aesthetics of the light pattern.
[0006] like Figure 4 A comparative diagram of the ideal output pattern AA and the actual output pattern BB. In the diagram, the ideal output pattern AA has slanted straight edges, while the actual output pattern BB has obvious jagged edges.
[0007] In addition, some studies have mentioned that pixel density enhancement may be achieved through single-module vibration, but this method is not practical on a platform where the car itself experiences significant vibration.
[0008] Therefore, it is necessary to propose an efficient, reliable solution that can improve pixel density and eliminate the jagged edges and screen-door effect without high-speed mechanical movement. Summary of the Invention
[0009] This invention provides a pixel density enhancement system based on dual static modules. By using two identical projection modules, the effective pixel density can be increased by nearly 4 times without increasing the number of physical pixels per chip, significantly eliminating the jagged edge effect and screen door effect, and improving the accuracy of light pattern control.
[0010] To address the problems of existing technologies, this invention discloses a pixel density enhancement system based on dual static modules, comprising identical projection modules A and B. Both projection modules A and B include a microdisplay chip. Projection module B is statically assembled within a headlamp assembly such that the image projected onto the target plane is geometrically misaligned relative to the image of projection module A in both the horizontal and vertical directions, or in one of these directions, by a precise 0.5 pixel unit. This misalignment aims to enhance the light pattern pixel density through the superimposed projection of the two modules. The microdisplay chip is a microLED array.
[0011] Preferably, it includes three or more projection modules.
[0012] A method for projecting automotive lighting patterns based on a pixel density enhancement system with dual static modules includes the following steps:
[0013] 1.) Acquire high-resolution light pattern image data of the target;
[0014] 2.) Decompose the target high-resolution light pattern image data into at least two low-resolution subsets;
[0015] 3.) Assign the low-resolution subset to projection modules A and B, which have the same physical pixel array;
[0016] 4.) By utilizing the 0.5-pixel misalignment of the projection module B relative to the projection module A during static assembly, the subset light patterns of the projection module A and the projection module B are interleaved and superimposed on the target plane to reconstruct a high pixel density light pattern.
[0017] Preferably, the projection module A and the projection module B are configured to have identical patterns with stable spatial misalignment.
[0018] Preferably, the projection module A and the projection module B are configured as identical patterns with relative changes and spatial misalignment.
[0019] The beneficial effects of this invention are as follows: by using two identical projection modules and assembling them so that the projected image of one module is precisely misaligned by 0.5 pixels relative to the other module on the target plane, this system can increase the effective pixel density to nearly 4 times without increasing the number of physical pixels on a single chip, doubling it on both the X and Y axes, significantly eliminating the jagged effect and screen door effect, and improving the accuracy of light pattern control.
[0020] When this invention is applied to adaptive high beams or digital headlights, the main advantage of pixel interleaving is:
[0021] Anti-aliasing: This is the most significant improvement, easily noticeable to the human eye. Headlights block oncoming vehicles by pixelating the beam. Without subpixel interleaving, the edges of the blocked beam would have noticeable pixel steps (aliasing), affecting the driving experience and the precision of light control. Dual-module interleaving eliminates these aliasing marks.
[0022] Improved edge smoothness: This smoothness significantly enhances perceived clarity. The system needs to precisely "draw" the avoidance area. A 0.5-pixel displacement can double the resolution of the beam edge, allowing the system to cut the beam more finely and accurately, thus making the use of high beams safer. It also noticeably improves the visual experience when projecting patterns onto the ground.
[0023] Reduced cost / power consumption: Compared to using a chip with twice the resolution (if available), using two low-resolution chips interleaved can reduce hardware costs and driver complexity (provided the driver frequency is high enough).
[0024] Reliability: The system has no moving parts, resulting in higher reliability, making it particularly suitable for automotive applications. Attached Figure Description
[0025] Figure 1 This is a schematic diagram of a traditional vehicle headlight projection module.
[0026] Figure 2 Application scenario 1 for traditional vehicle headlight projection modules (partial overlay application).
[0027] Figure 3 Application scenario 2 for traditional vehicle headlight projection modules (complete overlay application).
[0028] Figure 4 This is a diagram comparing the ideal output pattern AA and the actual output pattern BB.
[0029] Figure 5 This is a schematic diagram of the misaligned superimposed image of the first embodiment (a higher resolution bevel (40*40 pixels) is achieved by misaligning and superimposing two low-pixel projected images (20*20 pixels).
[0030] Figure 6 This is a schematic diagram of the misaligned superimposed image in the second embodiment (a higher resolution pattern (160*160 pixels) is achieved by misaligning and superimposing two low-pixel projected images (80*80 pixels)).
[0031] Figure 7 This is a schematic diagram of the misaligned superimposed image in the third embodiment (a higher resolution pattern (80*80 pixels) is achieved by misaligning and superimposing two low-pixel projected images (40*40 pixels)). Detailed Implementation
[0032] To further understand the features, technical means, and specific objectives and functions achieved by the present invention, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.
[0033] The basic scheme of the three embodiments of the present invention is as follows: both projection modules A and B are identical, integrated within the automotive headlight assembly and driven by a central controller. As a preferred embodiment, three or more projection modules may also be included.
[0034] Among them, such as Figure 1 As shown, both projection module A and projection module B contain pixelated light sources or image sources and projection optical lenses.
[0035] The key geometric configuration consists of two architectures, with projection module A and projection module B having partially overlapping fields of view, such as... Figure 2 Or the entire field of view overlaps as Figure 3 The former, with partial field-of-view overlap, can expand the field of view to a larger extent.
[0036] The actual operation method is as follows:
[0037] 1.) Acquire high-resolution light pattern image data of the target;
[0038] 2.) Decompose the high-resolution light pattern image data of the target into at least two low-resolution subsets;
[0039] 3.) Assign the low-resolution subset to projection modules A and B, which have the same physical pixel array;
[0040] 4.) By utilizing the 0.5-pixel misalignment of the projection module B relative to the projection module A during static assembly, the subset light patterns of the projection module A and the projection module B are interleaved and superimposed on the target plane to reconstruct a high pixel density light pattern.
[0041] Assumption:
[0042] Projection module A was selected as the reference module.
[0043] The mounting position and angle of projection module B in the headlight assembly are precisely calibrated to ensure that the overlapping image projected onto the target plane (e.g., the road surface) has a precise geometric misalignment of 0.5 pixels relative to the image of projection module A in both the horizontal (assuming X-axis) and vertical (Y-axis) directions.
[0044] This 0.5-pixel misalignment is a permanent, static physical misalignment that does not require mechanical vibration during operation.
[0045] First implementation method, such as Figure 5 As shown, the system architecture is as follows: Figure 2 As shown in Figure 3, the projected pattern is a triangle with a hypotenuse. Assuming both projection modules A and B are 20*20 pixels, the light spot projected by projection module B onto the receiving surface is misaligned by 0.5 pixels in both the x and y directions from projection module A. This manifests as a stable deviation of (+0.5 pixels, +0.5 pixels), i.e., shifted to the right and lower by half a pixel. The patterns of both modules represent two low-resolution subsets of an ideal high-resolution 40*40 image. The composite image obtained by superimposing projection modules A and B is a 40*40 high-resolution triangle with a hypotenuse. Figure 5 In the image, it is clearly visible that the hypotenuse of the triangle is more refined, and the jagged edges are significantly improved.
[0046] Second implementation method, such as Figure 6 As shown, the system architecture is as follows: Figure 2 As shown in Figure 3, the projected pattern is the number 72 (which can be interpreted as a speed limit). Assuming both projection modules A and B are 80*80 pixels, the light spot projected by projection module B onto the receiving surface (which could be the ground) is misaligned by 0.5 pixels in both the x and y directions from projection module A. This manifests as a stable deviation of (-0.5 pixels, +0.5 pixels), i.e., shifted to the left and lower half a pixel. Both patterns represent two low-resolution subsets of an ideal high-resolution 160*160 image. Superimposing projection modules A and B yields a composite image of a high-resolution 160*160 pattern with the number 72. From the image, it is clear that the composite image is more delicate, softer, and smoother, with a significant improvement in jagged edges.
[0047] The third implementation method, such as Figure 7 As shown, the system architecture is as follows: Figure 2As shown in Figure 3, the projected pattern is an isosceles triangle (which can be understood as a light carpet over a roadway). Assuming both projection module A and projection module B are 40*40 pixels, the light spot projected by projection module B onto the receiving surface (which could be the ground) is misaligned by 0.5 pixels in both the x and y directions compared to projection module A. For the same image, the image of projection module A is represented by only the same subframes, while the image of projection module B is composed of three different subframes. The actual representation is as follows:
[0048] The deviation of subframe 1 (+0.5 pixels, +0.5 pixels) is that it is shifted to the right and lower half a pixel.
[0049] The deviation of subframe 2 (+0.5 pixels, -0.5 pixels) is that it is shifted to the right and upper half a pixel.
[0050] The deviation in subframe 3 (-0.5 pixels, +0.5 pixels) is that it is shifted to the left and lower half a pixel.
[0051] Subframes 1-3 can be lit sequentially, with a duration dependent on the drive, but less than the human eye's residual time. To ensure that the human eye does not perceive flicker and perceives a stable, high-resolution image, the maximum time required for a complete subpixel interleaving cycle (N subframes) should be less than 16.7ms.
[0052] The two patterns are two low-resolution subsets of an ideal 80*80 pixel high-resolution light pattern image data. After superimposing projection modules A and B, a composite image of 80*80 high-resolution isosceles triangle patterns is obtained. From the image, it is clear that the composite image is more delicate, softer, and smoother, with a significant improvement in jagged edges. However, in automotive applications, the drive controller for this application would be slightly more complex.
[0053] The above-described embodiments are merely three examples of implementation methods of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.
Claims
1. A pixel density enhancement system based on dual static modules, characterized in that: It includes identical projection modules A and B, each containing a microdisplay chip. Projection module B is statically assembled within the headlamp assembly such that the image projected onto the target plane has a precise geometric misalignment of 0.5 pixels in both the horizontal and vertical directions, or in one of the directions, relative to the image of projection module A. This misalignment is intended to enhance the light pattern pixel density through the superimposed projection of the two modules.
2. A method for projecting automotive lighting patterns based on claim 1, characterized in that... Includes the following steps: 1.) Acquire high-resolution light pattern image data of the target; 2.) Decompose the target high-resolution light pattern image data into at least two low-resolution subsets; 3.) Assign the low-resolution subset to projection modules A and B, which have the same physical pixel array; 4.) By utilizing the 0.5-pixel misalignment of the projection module B relative to the projection module A during static assembly, the subset light patterns of the projection module A and the projection module B are interleaved and superimposed on the target plane to reconstruct a high pixel density light pattern.
3. The automotive lighting beam projection method according to claim 2, characterized in that, The projection module A and the projection module B are configured to have identical patterns with stable spatial misalignment.
4. The automotive lighting beam projection method according to claim 2, characterized in that, The projection module A and the projection module B are set to identical patterns with relative changes and spatial misalignment.
5. A pixel density enhancement system based on dual static modules according to claim 1, characterized in that, The microdisplay chip is a microLED array.
6. A pixel density enhancement system based on dual static modules according to claim 1, characterized in that, It contains 3 or more projection modules.