KR101085812B1 - Method for detection of elbow points in a light axis adjusting method of downward headlight - Google Patents

Abstract

assignment

The present invention is an improvement of the existing invention, and develops a more accurate and stable optical axis adjustment method of the headlight, which can cope with the actual state of the modern head lamp optical axis adjustment method.

Solution

At a predetermined distance in the horizontal direction centered on a specific position on the horizontal line from the center of the camera, the contrast boundary point is determined by the inclination setting value of the contrast boundary of the light distribution, and an approximation value obtained by the mean value or the least square method from these contrast boundary points is A. From the intersection point B which intersects the inclination line in the horizontal direction from the position set in the up-down direction from the A, the inclination line is obtained by the least square method at a predetermined interval of the specified number of pixels on the inclination line, and is horizontal from the intersection B. The horizontal line is obtained by the least square method from a predetermined pixel interval on the horizontal line with respect to the position C set in the direction, and the intersection of the horizontal line and the inclined line obtained as the elbow point is adjusted to the elbow point, and the optical axis is adjusted to fall within the standard range. In the optical axis adjustment method of the downward headlight Elbow point detection method.

 Downward headlight, elbow point

Description

The elbow point detection method in the optical axis adjustment method of a downward headlight {METHOD FOR DETECTION OF ELBOW POINTS IN A LIGHT AXIS ADJUSTING METHOD OF DOWNWARD HEADLIGHT}

1 is a flow chart showing a processing routine.

2 is an explanatory diagram showing an embodiment of an optical axis adjusting method of a headlight of the present invention.

3 is an explanatory diagram showing an embodiment of an optical axis adjusting method of a headlight of the present invention.

4 is an explanatory diagram showing an embodiment of an optical axis adjusting method of a headlight of the present invention.

5 is an explanatory diagram showing an embodiment of the present invention.

Fig. 6 is an explanatory diagram showing another embodiment of the usage method of the present invention (a three-point balance system with fixed three positions).

7 is a schematic cross-sectional view showing an optical axis adjusting device used in the present invention.

Explanation of the sign

1: imaging lens 2: half mirror

3: screen 4: photometric substrate

5: CCD camera 6: lens unit

A: Approximate value obtained by the mean or least squares method from the contrast boundary

B: intersection point intersecting the inclined line in the horizontal direction from the position set in the vertical direction

B ': intersection

C: position set in the horizontal direction from the intersection

Patent Document 1: Japanese Patent No. 2058841

Patent Document 2: Japanese Patent No. 2778850

Patent Document 3: Japanese Unexamined Patent Publication No. 2000-146761

In the light distribution pattern image on the screen surface on which light from the downward headlight is transmitted, an intersection point (called elbow point) of a horizontal cut line and an inclined cut line constituting a cut line from a contrast boundary point is a predetermined inspection pass region. An optical axis adjustment method of a downward headlight which adjusts an optical axis whether it exists in the inside.

Conventionally, in the optical axis adjustment method of the downward headlight, the pixel group in the image processing technique is replaced with three sensor positions as shown in Fig. 3, and the three pixel groups at each position are optically balanced. The horizontal axis and the inclination line which pass through the position which hold | maintained were made into the horizontal cut line and the inclined cut line, and the intersection was made into the elbow point, and the optical axis adjustment method of whether the elbow point falls in the predetermined test | pass acceptance area was performed.

However, in recent years, the head lamp itself has changed with the passage of time, and especially the angle of the inclined cut line is not only 15 degrees, for example, 13 degrees, 17 degrees, Z type or the like, or HID lamp (xenon lamp) And high brightness by LED lamps and the like, a method of adjusting the optical axis of the head lamp with higher accuracy is required. Patent Documents 1, 2 and 3 are examples.

Therefore, the objective of this invention is based on "the optical-axis adjustment method of the headlight" which is invention (henceforth a basic invention) of Unexamined-Japanese-Patent No. 2000-146761 developed by this applicant of the said prior art, This basic invention was further developed to develop the invention of Japanese Patent Application No. 2005-355941. However, the present invention is to develop a more precise and stable optical axis adjusting method for the headlight which can cope with the situation of the modern head lamp optical axis adjusting method. . In addition, a judgment criterion different from the conventional lamp was added to the recently developed Z lamp.

Therefore, this invention implemented the improvement means about the measurement part of "the optical axis adjustment method of a headlight" which is a basic invention, and developed the following invention.

In the adjustment method of a basic invention, one of them sets the standard range which consists of a predetermined rectangular area | region as described in Claim 2 of the basic invention, and the part of an optical axis depends on whether elbow point EP exists in this standard range. (Iii), the optical axis adjustment method of the headlight according to claim 1 characterized in that the measurement method is based on the other hand. This is to be solved by a stable new optical axis measurement and adjustment method.

Carrying out the invention  Best form for

2, 3, 4 and 5, an embodiment of the present invention will be described in detail. For a light distribution pattern image on a screen surface on which light from a downward headlight is transmitted, a cut line which is a contrast boundary is formed. An optical axis adjustment method of a headlight that obtains a horizontal contrast boundary (hereinafter referred to as a cut line) and an inclined cut line, and inspects and adjusts an optical axis to determine whether an elbow point where they intersect is within a predetermined standard range. From V), at a predetermined interval in the horizontal direction centering on a specific designated position in the horizontal cut line, the contrast boundary point is determined by the maximum value (set value) of the contrast boundary line slope of the light distribution, and the average or approximation value is obtained from these contrast boundary points. A), and the intersection crossing the inclined cut line in the horizontal direction from the position set in the vertical direction from the approximation A If (B) is found or the intersection point (B) cannot be found, the position set in the up-down direction is moved up and down again to find the intersection point (B) 'and newly replace the intersection point (B)' with the intersection point (B). ) When a plurality of points set from the intersection point B are obtained, the cut line is obtained from the contrast boundary point in the same manner as the horizontal portion between the predetermined intervals, and if the slope is within the predetermined value, the cut line is recognized as a Z-type down ramp. In the predetermined interval of the specified number of pixels on the inclined cut line from the intersection (B), the inclined cut line is obtained by a method such as least square method, and the horizontal cut line from (C) set in the horizontal direction from the intersection (B) and A horizontal cut line is obtained by a method such as least square method at predetermined intervals of the designated number of pixels on the horizontal line around the intersection point D that intersects, and the intersection point of the horizontal cut line and the inclined cut line obtained above is “elbow”. Point ”, and the optical axis of the downward headlight is adjusted so that the“ elbow point ”falls within the standard range. It consists of the "elbow point" detection method in the method.

However, when it is recognized that the image is not a Z-type downward headlight (light having a normal cut line), the inclined cut line and the horizontal cut line are controlled by a variable three-point pixel group balance method in the designated pixel group. In the optical axis adjustment method of the downward headlight, the optical axis is adjusted so that the "elbow point" falls within the standard range, similarly to the Z-shaped downlight. Elbow point ”.

Example

Best Mode for Carrying Out the Invention A preferred embodiment of the present invention will be described below with reference to the accompanying drawings. Fig. 1 is a flowchart showing the elbow point detection method in the optical axis adjustment method of the headlight according to the present invention, and the elbow point detection method is composed of first steps (S1) to fifteenth steps (S15).

In 1st step S1, as shown in FIG. 2, the horizontal predetermined space | interval Y centering on the specific position in the horizontal line is calculated | required from the camera center position V. FIG.

In a 2nd step S2, the setting value (maximum value) of the inclination of each cut illuminance curve is made into the contrast boundary point in the horizontal direction designation pixel space in the (Y) space | interval.

In 3rd step S3, as shown in FIG. 2, the approximation value A according to the average value of the horizontal direction of the contrast point in the (Y) space | interval, or the least squares method is calculated | required.

In the 4th step S4, the intersection which intersects the inclination contrast boundary line in the horizontal direction arbitrarily set to the up-down direction from the approximation value A is made into (B).

In the fifth step S5, when there is an intersection point B, the inclined contrast border and the horizontal contrast border in the eighth step S8 are obtained by a three-point pixel group balance method of three positions as a down ramp. In the Z type downward ramp in which the intersection B may not be found, the process of the 6th step S6 is performed.

In the sixth step S6, when the intersection point B cannot be found, the point where the vertical direction is arbitrarily determined is moved up and down.

In the seventh step (S7), the intersection point obtained by moving up and down is obtained as (B) ', and is newly established as the intersection point (B).

In the eighth step (S8), the ninth step (S9) and the tenth step (S10), if the inclination of the cut line is within a specified point at a plurality of points set by a predetermined interval from the intersection point B, it is recognized as a Z-type downlight. do.

In the eleventh step S11, when it is considered that the light is not normally a Z-shaped downlight but a light of a normal cut line, an inclined cut line and a horizontal cut line are obtained by a three-point pixel group balance method at three possible positions.

In the twelfth step S12, when it is recognized as a Z-type downlight, the inclined cut line is obtained from the intersection point B by the least square method at a predetermined interval of the specified number of pixels on the inclined line.

In the thirteenth step S13, the intersection point D intersects the horizontal cut line from the position C set in the horizontal direction from the intersection point B, and the horizontal cut is performed from the predetermined pixel interval in the horizontal direction by the least square method or the like. Find the line.

In the fourteenth step S14, the intersection point of the horizontal cut line and the inclined cut line previously obtained is an elbow point.

In the fifteenth step S15, the optical axis is adjusted so that the obtained elbow point falls within the standard range.

As described above, another embodiment of the optical axis adjusting method of the downward headlight according to the present invention will be described in detail with reference to the drawings. As shown in Fig. 2, the distance between the camera center position and 2.5 ° to 3.5 ° (the distance between y1 and y2). ), The contrast boundary point is determined by the set value (maximum value) of the slope of the contrast boundary point, and (A) is obtained from the approximation value (at the position of 3.0 °) obtained by the average value or the least square method of the contrast boundary point.

The slope cut line is determined by the least square method at a maximum ± 0.5 ° variable width (between ± 32 dots) on the slope from the point B which cuts the slope in the horizontal direction from 0.5 ° on the position of (A).

(a)

2.8°) 이면 Z 형 하향 라이트로 한다. However, when the inclined boundary line cannot be found, as shown in Fig. 1, 0.5 ° is lowered to 0.4 ° or 0.25 ° (set value) to obtain the intersection (B) ', and (B)' is the new intersection B. ) Since the processing method of the Z-type downward lamp is different from that of the normal lamp, a plurality of points ((B) + 1.5 °, (B) + 2.0 °, (B) + 2.5 °, The slope (a) of the contrast boundary in (B) + 3.0 °) is within the specified range (-2.8 °).

(a)

2.8 °), Z downlight.

(B) A horizontal cut line is determined by the least square method at a ± 0.5 ° (± 32 dot) interval on the horizontal line from a point (C) of 4 ° in the horizontal direction from the point, and the intersection of the inclined cut line is determined. Elbow point. This is to adjust the optical axis so that the obtained elbow point is within the specification range. However, in the case where the ramp is normally downgraded due to the inclination of the light and dark boundary lines at the plurality of points, the inclined cut line and the horizontal line obtained by the variable three-point pixel group balance method (variable width 8.53 ° to 60 °) are horizontal. Determine the elbow point from the cut line.

In addition, the down write measurement program will be described. The processing routine of the down write measurement method is as follows.

(1) Contrast of maximum contrast (setting value) of the slope of each cut illuminance curve in the horizontally-specified pixel interval in the ± 0.5 degree interval [y1, y2] centered on the right 3 degree point from the camera center position (V). It is done. Between [y1, y2], the approximation value by the linear formula of the contrast point up-down direction is made into "A".

(2) A straight line is drawn in the horizontal direction at an upper 0.25 degree position from "A", and the intersection of the inclination roughness curve is set to "B" (see FIG. 2).

a

2.8도가 되면 Z 빔 배광으로 판단한다 ([도 3] 참조).(3) From the "B" to the left, the slope a of 1.5, 2, 2.5, and 3 degrees is determined, and the numerical value is -2.8 degrees at three or more places.

a

If it is 2.8 degrees, it is determined as Z-beam light distribution (see FIG. 3).

<1> When judged by Z beam light distribution in (3).

1. Make the position of right 4 degrees from point "B" as C point, calculate approximate value "D" by the straight-line up and down direction of contrast point in left and right ± 0.5 degree interval from point C, and draw a horizontal line from the position, Set the intersection point with the inclined cut line as the elbow point. See FIG. 4

<2> When it is determined in (3) that it is not Z beam light distribution

1. From "B", the slope cut line is calculated | required by the minimum square method with the maximum width of +/- 0.5 degree, and the slope b is computed.

b<11.3도, 11.3도

b<14.0도, 14.0도

b<16.7도, 16.7도

b 중 어느 하나가 될지 (가변 설정이 가능하도록 한다) 를 판단하고, 그 범위에 따라 가변의 3 위치의 3 점 화소군의 밸런스 배치의 경사 커트부 좌측의 3 점 (G, H, I) 위치를 변경한다. [도 5] 참조 2. The value of the slope b is b <8.53 degrees, 8.53 degrees

b <11.3 degrees, 11.3 degrees

b <14.0 degrees, 14.0 degrees

b <16.7 degrees, 16.7 degrees

It judges which one of b (it is possible to set a variable), and the three point (G, H, I) position of the left side of the inclination cut part of the balance arrangement | positioning of the 3-point pixel group of a variable 3-position according to the range. Change See FIG. 5

3. Each pixel (5x) while maintaining the image data positions of 9 points of A, B, C, D, E, F, G, H, I based on the defined sensor positions of "G, H, I". 5) Find the elbow point by detecting the point where the brightness of the minute sum is the smallest difference between left, right, and top.

Left-right direction (D-E)-(E-F) + (G-H)-(H-I) = 0

Up-down direction (A-B)-(B-C) = 0

In the conventional fixed three-position three-point pixel group balance method [FIG. 6], stable measurement results equivalent to those of the naked eye were obtained for lamps such as light distribution and Z-beam light distribution whose angles of cut line inclination were greatly deviated from the standard 15 degrees. The above method is used as the measurement method to be calculated as.

And when the optical axis adjustment device used for the optical axis adjustment method which concerns on this invention is demonstrated, FIG. 7 shows the optical axis adjustment device which concerns on this invention, This optical axis adjustment device is an optical axis C (lamp) of a headlight. The imaging lens 1 provided on the image, the half mirror 2 arranged behind the imaging lens 1, the screen 3 arranged behind the half mirror 2, and the half mirror 2. The photometer board 4 arrange | positioned immediately above and the CCD camera 5 which image | photographs the transparent image of the screen 3 are provided in the lens unit 6 inside.

About the downlight measurement program,

The present invention has industrial applicability by establishing the technique of the elbow point detection method of the optical axis adjustment method of the headlight and actually using it.

According to the present invention, in response to various modern light distribution specifications, in particular, the confusion of the light caused by the opposite vehicle in the night driving of the vehicle depends on how accurately the cut line detection of the downward headlight is measured and adjusted. Eliminating) has an extremely beneficial effect, such as how much can reduce traffic accidents in society.

Claims (2)

The optical axis adjusting device obtains a horizontal cut line and an inclined cut line constituting a cut line, which is a contrast line, on the light distribution pattern image on the screen surface on which light from the downward headlight is transmitted, and the horizontal cut line and the inclined cut line. As an elbow point detection method in the optical axis adjustment method of the headlight which inspects and adjusts an optical axis whether this crossed elbow point exists in the predetermined standard range, From the camera center position (V), the contrast boundary point is determined by the maximum value (determined value) of the inclination of the contrast boundary of the light distribution at a predetermined interval in the horizontal direction centered on the specific designated position in the horizontal cut line, An average value or an approximation value is set to (A) from the light and dark boundary point, From the approximate value A, the intersection point B intersects the inclined cut line in the horizontal direction from the position set in the up-down direction, or if the intersection point B cannot be found, the position set in the up-down direction is moved up and down again. To find the intersection (B) 'and newly make the intersection (B)' the intersection (B), A cut line is obtained from the contrast boundary point by the method in which (A) is obtained at a plurality of points set from the intersection point (B), When the slope of the cut line is within a predetermined value, it is recognized as a Z-type down ramp, In the case of the Z-type down ramp, From the intersection point B, the oblique cut line is obtained by the least square method at a predetermined interval of the specified number of pixels on the oblique cut line. The horizontal cut line is obtained by the least square method at the predetermined interval of the specified number of pixels on the horizontal line at the intersection D intersecting the horizontal cut line from (C) set in the horizontal direction from the intersection B. Let the elbow point be the intersection of the said horizontal cut line and the cut line calculated | required previously, The elbow point detection method in the optical axis adjustment method of the downward headlight characterized by adjusting an optical axis so that the said elbow point may fall within a specification range. The optical axis adjusting device obtains a horizontal cut line and an inclined cut line constituting a cut line, which is a contrast line, on the light distribution pattern image on the screen surface on which light from the downward headlight is transmitted, and the horizontal cut line and the inclined cut line. As an elbow point detection method in the optical axis adjustment method of the headlight which inspects and adjusts an optical axis whether this crossed elbow point exists in the predetermined standard range, From the camera center position (V), the contrast boundary point is determined by the maximum value (determined value) of the inclination of the contrast boundary of the light distribution at a predetermined interval in the horizontal direction centered on the specific designated position in the horizontal cut line, An average value or an approximation value is set to (A) from the light and dark boundary point, From the approximate value A, the intersection point B intersecting the inclined cut line in the horizontal direction is obtained from the position set in the up-down direction, or if the intersection point B cannot be found, the position set in the up-down direction is moved up and down again. To find the intersection (B) 'and newly make the intersection (B)' the intersection (B), A cut line is obtained from the contrast boundary point by the method in which (A) is obtained at a plurality of points set from the intersection point (B), When the slope of the cut line is within a predetermined value, it is recognized as a Z-type down ramp, In the case of the Z-type down ramp, From the intersection point B, the oblique cut line is obtained by the least square method at a predetermined interval of the specified number of pixels on the oblique cut line. The horizontal cut line is obtained by the least square method at the predetermined interval of the specified number of pixels on the horizontal line at the intersection D intersecting the horizontal cut line from (C) set in the horizontal direction from the intersection B. When the intersection between the horizontal cut line and the cut line obtained above is an elbow point, and the optical axis is adjusted so that the elbow point is within a standard range, If it is recognized as a light having a normal cut line rather than the Z-shaped down light, An inclined cut line and a horizontal cut line are obtained by a variable three-point pixel group balance method in the designated pixel group, The elbow point in the optical axis adjustment method of the down-headlight, characterized in that the optical axis is adjusted so that the elbow point falls within the standard range in the same manner as the Z-type downlight with the intersection of the inclined cut line and the horizontal cut line as the elbow point. Detection method.

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