Detection method and system of steering projection lamp

Abstract

The invention relates to the technical field of projection detection, in particular to a steering projection lamp detection method and system, and the method comprises the steps: 1, collecting projection images: collecting the projection images through a camera, carrying out the binarization of the images collected by the camera, obtaining a gray image, and carrying out the detection of the gray image; carrying out contour extraction and corner detection on the image; 2, setting a section line along the X-axis direction, obtaining an intersection point between the section line and the projection pattern, and carrying out a brightness gradient test; connecting two front and rear points of the projection pattern to form a straight line L, and calculating the distance between the other points and the straight line L to carry out consistency test; and reading gray values of edge angular points of the projection pattern and gray values of area point positions among the plurality of dovetail-shaped patterns, and carrying out darkness test. Through different test items, the optical performance of the steering projection lamp is effectively controlled, the test method is simple, and comprehensive quality evaluation can be quickly made on the optical performance of the projection lamp.

Description

Technical Field

[0001] This application relates to the field of projection detection technology, and in particular to a detection method and system for a directional projection lamp. Background Technology

[0002] Driven by the wave of intelligentization, automotive optical systems are undergoing a technological leap. As a crucial carrier of human-vehicle-environment interaction, the function of turn signal lights has evolved from basic signal indication to dynamic light field construction and adaptive environmental interaction. Current evaluation systems based on traditional photometric and colorimetric parameter detection are insufficient to effectively assess the optical performance of new turn signal lights in dimensions such as pattern gradient and darkness. Therefore, there is an urgent need to develop a comprehensive quality evaluation scheme that considers the multi-dimensional optical characteristics of projected patterns. Summary of the Invention

[0003] The technical problem to be solved by this invention is: how to quickly evaluate the optical performance of a projection lamp in dimensions such as pattern gradient and darkness.

[0004] Therefore, the present invention provides a method and system for detecting turn signal projection lights.

[0005] The technical solution adopted by this invention to solve its technical problem is:

[0006] A method for detecting a directional projection light, comprising,

[0007] Step 1: Projection image acquisition. The projection pattern consists of multiple dovetail patterns spaced apart along the X-axis. The projection image is acquired by a camera, and the image acquired by the camera is binarized to obtain a grayscale image. Contour extraction and corner detection are then performed on the image.

[0008] Step 2: Set a cross line along the X-axis, obtain the intersection point between the cross line and the projected pattern, and perform a brightness gradient test; connect the two points before and after the projected pattern with a straight line L, calculate the distance between the remaining points and the straight line L, and perform a consistency test; read the gray values ​​of the edge corner points of the projected pattern and the gray values ​​of the points in the area between multiple swallowtail patterns, and perform a darkness test.

[0009] Furthermore, in step one, the distance between the light-emitting position of the projection lamp and the plane where the projection pattern is located is Ly = a ± 5 mm, where a is the nominal value of Ly.

[0010] Furthermore, the brightness gradient test includes: taking multiple cross-sections along the (X direction) and intersecting them with the pattern to form multiple intersection points, and then using a formula... Among them, E n+1 E represents the illuminance of the pixel at the (n+1)th intersection point. n Let be the illuminance of the pixel at the nth intersection point.

[0011] Furthermore, in the brightness gradient test, if the brightness gradient at the intersection of the cut-off line and the rear side of the projected pattern is greater than the threshold b, and the brightness gradient at the intersection of the cut-off line and the front side of the projected pattern is less than the threshold c, then the test of the turning projection lamp ladder is qualified; otherwise, it is unqualified.

[0012] Furthermore, in the consistency test, from front to back, the forward-protruding vertices of the three swallowtail patterns are denoted as c2, c1, b2, b1, a2, a1. Points a1 and c2 are fitted to a straight line L. The shortest distances D1, D2, D3, and D4 from a2, b1, b2, and c1 to the straight line L are calculated. If D1, D2, D3, and D4 are all less than the threshold, the consistency test is considered to be qualified.

[0013] Furthermore, in the darkness test, the maximum gray value Hm in the projected pattern is read, the gray value Hn of the points between multiple swallowtail patterns is read, and the darkness Wn = Hn / Hm is calculated. If Wn ≤ the threshold, the darkness test is qualified; otherwise, it is judged as unqualified.

[0014] Furthermore, if the brightness gradient test, consistency test, and darkness test are all qualified, the quality of the directional projection lamp is determined to meet the requirements.

[0015] A detection system for a turn-by-turn projection light includes a turn-by-turn projection light, a positioning fixture, a diffuse reflection screen, an industrial camera, an industrial control computer, and a regulated power supply. The regulated power supply is used to power the projection turn-by-turn light, the positioning fixture is used to fix the projection turn-by-turn light, the turn-by-turn projection light projects a pattern onto the diffuse reflection screen, the industrial camera automatically captures the pattern on the screen, and the industrial camera is connected to the industrial control computer.

[0016] The beneficial effect of this invention is that projection testing based on a dovetail pattern, through its unique vertex and directional design, "magnifies" minute angular errors into translational errors that are easier to observe and measure. By conducting various test items, the optical performance of the directional projection lamp can be effectively controlled. This testing method is simple and can quickly provide a comprehensive quality evaluation of the projection lamp's optical performance. Attached Figure Description

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0018] Figure 1 This is a schematic diagram of the projection of the steering projection lamp in this invention.

[0019] Figure 2 This is a schematic diagram of the projected pattern in this invention.

[0020] Figure 3 This is a schematic diagram of the brightness gradient test in this invention.

[0021] Figure 4 This is a schematic diagram of the consistency test in this invention. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0023] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0024] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] A detection system for a directional projection light includes a directional projection light, a positioning fixture, a diffuse reflection screen, an industrial camera, an industrial computer, and a regulated power supply. The directional projection light is lit by the regulated power supply and fixed on the positioning fixture so that its pattern is projected onto the diffuse reflection screen. The industrial camera automatically captures the pattern on the screen and transmits it to the industrial computer for image processing.

[0026] A method for detecting a directional projection light, comprising:

[0027] Step 1: Install the lamp under test and fine-tune the pitch angle. The specific method is as follows: Fix the directional projection lamp to the fixture using locating pins. The fixture and locating pins achieve precise positioning. Turn on the directional projection lamp using a regulated power supply, projecting the pattern onto the diffuse reflection screen. Mark the upper and lower limits of the pattern's vertices on the screen, and fine-tune the dimming mechanism on the directional projection lamp to adjust the pitch angle so that Ly = a ± 5mm. Here, Ly is the horizontal distance in the Y direction from the pattern vertex to the light output center, and a is the nominal value of Ly, where a = 300.

[0028] It should be noted that the pattern used in the projection detection is a series of spaced-apart dovetail-shaped patterns. In this embodiment, there are three dovetail-shaped patterns, such as... Figure 1 As shown, after projection, multiple swallowtail patterns are spaced apart along the X-axis, with the pointed tips of the swallowtails pointing in the X-axis direction, and the direction of the swallowtail tips is taken as the front end.

[0029] Step 2: Image Processing

[0030] The projected image is captured by a camera and then binarized to obtain a grayscale image. Contour extraction is performed on the image to obtain the outermost contours of the three swallowtail patterns. Corner detection is then performed on the extracted contours to obtain all the corners of the swallowtail patterns.

[0031] From front to back, label the forward-protruding vertices of the three swallowtail patterns as c2, c1, b2, b1, a2, a1; label the vertices of the left edges of the three swallowtail patterns as c5, c3, b5, b3, a5, a3; and the vertices of the right edges as c6, c4, b6, b4, a6, a4; label the midpoint between c3 and b5 as m5; the midpoint between b3 and a5 as m3; the midpoint between c1 and b2 as m2; the midpoint between b1 and a2 as m1; the midpoint between c4 and b6 as m6; and the midpoint between b4 and a6 as m4.

[0032] like Figure 2 As shown, ∠a1a3a5 is an acute angle, and ∠a3a5a2 is an obtuse angle. Based on this information, identify the corner points and name and number them.

[0033] Based on the corner coordinates extracted from the contour, these points are identified in the original image, and image processing and calculations are performed according to the corresponding detection requirements.

[0034] Step 3: Perform brightness gradient test, consistency test, and darkness test in sequence.

[0035] The S3.1 luminance gradient test includes:

[0036] like Figure 2Three transverse lines are taken along the horizontal direction (X direction) of the pattern and intersect the pattern, forming a total of 18 intersection points. Intersection points G1 to G9 are where the transverse lines intersect the rear edge of the pattern; the rising gradient is calculated from intersection points G1 to G9. Intersection points G10 to G18 are where the transverse lines intersect the front edge of the pattern; the falling gradient is calculated from intersection points G10 to G18. The gradient calculation formula is... Among them, E n+1 E represents the illuminance of the pixel at the (n+1)th intersection point. n The illuminance of the pixel at the nth intersection point can be measured using an illuminance meter.

[0037] When F n > Threshold b (n = 1, 2, ..., 9), and F n If the value is less than the threshold c (n = 10, 11, ..., 18), then the test of the turning projection lamp ladder is qualified; otherwise, it is unqualified.

[0038] S3.2 conformance testing includes:

[0039] This test is primarily used to control the alignment of multiple swallowtail-shaped vertices pointing forward in a straight line. Figure 3 When the six vertices deviate from the straight line by more than a certain threshold, it will be clearly noticeable to the user, so it needs to be closely monitored.

[0040] The testing method is as follows ( Figure 4 Connect the frontmost vertex c2 of the projected pattern to the rearmost vertex a1 that protrudes forward. Fit points a1 and c2 to a straight line L. Find the shortest distances D1, D2, D3, and D4 from a2, b1, b2, c1 to the straight line L.

[0041] If D1, D2, D3, and D4 are all less than the threshold, the consistency test is considered to be qualified; otherwise, it is considered to be unqualified.

[0042] The S3.3 darkness test includes:

[0043] Read the gray levels of points a3 and a4 and take the maximum gray level as Hm. Read the gray levels Hn of points m1 to m6 (Hn is H1-H6), where points m1 to m6 are located at the center of two adjacent patterns.

[0044] Calculate the darkness Wn = Hn / Hm (n = 1 to 6). If Wn ≤ the threshold, the darkness test is considered qualified; otherwise, it is considered unqualified.

[0045] A turn signal light that passes all three tests can be considered to have a pattern quality that meets the requirements.

[0046] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined by the scope of the claims.

Claims

1. A method for detecting a directional projection light, characterized in that, include, Step 1: Projection image acquisition. The projection pattern consists of multiple dovetail patterns spaced apart along the X-axis. The projection image is acquired by a camera, and the image acquired by the camera is binarized to obtain a grayscale image. Contour extraction and corner detection are then performed on the image. Step 2: Set a cross line along the X-axis, obtain the intersection point between the cross line and the projected pattern, and perform a brightness gradient test; connect the two points before and after the projected pattern with a straight line L, calculate the distance between the remaining points and the straight line L, and perform a consistency test; read the gray values ​​of the edge corner points of the projected pattern and the gray values ​​of the points in the area between multiple swallowtail patterns, and perform a darkness test.

2. The detection method for turn signal projection lights according to claim 1, characterized in that, In step one, the distance between the light-emitting position of the projection lamp and the plane where the projection pattern is located is Ly = a ± 5 mm, where a is the nominal value of Ly.

3. The detection method for turn signal projection lights according to claim 1, characterized in that, The brightness gradient test includes: taking multiple cross-sections along the (X direction) and intersecting them with the pattern to form multiple intersection points, and then using a formula... Among them, E n+1 E represents the illuminance of the pixel at the (n+1)th intersection point. n Let be the illuminance of the pixel at the nth intersection point.

4. The detection method for turn signal projection lights according to claim 3, characterized in that, In the brightness gradient test, if the brightness gradient at the intersection of the cut-off line and the rear side of the projected pattern is greater than the threshold b, and the brightness gradient at the intersection of the cut-off line and the front side of the projected pattern is less than the threshold c, then the test of the turning projection lamp ladder is qualified; otherwise, it is unqualified.

5. The detection method for turn signal projection lights according to claim 1, characterized in that, In the consistency test, from front to back, the forward-protruding vertices of the three swallowtail patterns are denoted as c2, c1, b2, b1, a2, a1. Points a1 and c2 are fitted to a straight line L. The shortest distances D1, D2, D3, and D4 from a2, b1, b2, and c1 to the straight line L are calculated. If D1, D2, D3, and D4 are all less than the threshold, the consistency test is considered to be qualified.

6. The detection method for turn signal projection lights according to claim 1, characterized in that, In the darkness test, the maximum gray value Hm in the projected pattern is read, and the gray value Hn of the points between multiple swallowtail patterns is read. The darkness Wn = Hn / Hm is calculated. If Wn ≤ the threshold, the darkness test is qualified; otherwise, it is judged as unqualified.

7. The detection method for turn signal projection lights according to claim 1, characterized in that, If the brightness gradient test, consistency test, and darkness test are all qualified, the quality of the directional projection lamp is determined to meet the requirements.

8. A detection system for a directional projection light, characterized in that, The system includes a turn-by-turn projection light, a positioning fixture, a diffuse reflection screen, an industrial camera, an industrial computer, and a regulated power supply. The regulated power supply powers the turn-by-turn projection light, the positioning fixture fixes the turn-by-turn projection light, the turn-by-turn projection light projects a pattern onto the diffuse reflection screen, the industrial camera automatically captures the pattern on the screen, and the industrial camera is connected to the industrial computer.

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