JP4808871B2 - Surface texture evaluation device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a surface texture evaluation apparatus that quantitatively evaluates coating quality and surface texture quality such as metallic color coating and pearl mica coating at high speed over a wide range.
[0002]
[Prior art]
Japanese Patent Application Laid-Open No. 11-212673 discloses an apparatus for evaluating a painted surface of a metallic color coating or a pearl mica color coating in which the hue, brightness, and saturation of a surface change depending on the change in the incident angle and observation angle of a light beam from a light source. It is disclosed.
[0003]
This apparatus has a configuration in which a two-dimensional array sensor and an illumination held in a predetermined positional relationship are held in a state where they face each other at a predetermined distance with respect to a painted surface of an object to be measured. Then, by repeating the imaging over a wide range while moving the two-dimensional array sensor and the illumination relative to the object to be measured, the emission angles of the rays reflected from the same point of the object to be measured are different from each other. A plurality of images are obtained, and from each of the plurality of images, the brightness value of the same point of the object to be measured is extracted, thereby obtaining a variable luminance distribution, and based on this, the optical reflection property of the object to be measured is determined. This is a quantitative evaluation.
[0004]
However, since this device is configured using a two-dimensional array sensor, the imaging range (moving direction / width direction), the number of angle information, the image capturing speed, and the moving speed of the object to be measured are configured independently. It has a problem that it cannot be performed, there are many restrictions for practical use, and the setting is very complicated.
[0005]
That is, in the above apparatus, as shown in FIGS. 8 and 9, in order to obtain wide angle change information, it is necessary to widen the viewing angle of the two-dimensional array sensor. Specifically, when the two-dimensional array sensor 81 having a viewing angle α of 80 degrees is used (FIG. 8A), the parallel light 83, 45 ° with respect to the measured object moving direction 50 from the light source, Assuming that 84 and 85 are incident, the light 83a, 84a and 85a reflected by the surface 82 of the object to be measured is incident on the two-dimensional array sensor 81 at 85 degrees, 45 degrees and 5 degrees, respectively. Therefore, in this case, the angle change information in the range of 5 to 85 degrees can be obtained.
[0006]
However, when the two-dimensional array sensor 81 is used, the viewing angle is wide with respect to the width direction 51 of the object to be measured. That is, as shown in FIG. 8B, when measuring the central portion with respect to the width direction 51 of the object to be measured, the light 88 enters the array sensor 81 at a right angle. However, the incident angle with respect to the array sensor 81 increases as it approaches the edge of the field of view, and the light 86 and 88 enter the array sensor 81 with an inclination of 40 degrees at the edge of the field of view. That is, as it approaches the edge of the field of view, it has wide angle information even in the field width direction, which is ideal to have no change in the incident angle, and the evaluation performance deteriorates.
[0007]
Further, as shown in FIG. 9, by reducing the viewing angle β of the sensor array 81, the incident angle in the width direction of the object to be measured can be reduced. For example, as shown in FIG. 9B, when the viewing angle is 20 degrees, the incident angle in the measured object width direction 51 is as small as 10 degrees. However, this also narrows the angle information for the object movement direction 50 at the same time, and the range is drastically reduced to 35 to 55 degrees, and the evaluation performance deteriorates. That is, narrowing the viewing angle to improve the performance in the viewing width direction leads to narrowing of the angle information in the moving direction.
[0008]
In addition, as shown in FIG. 10, in order to eliminate the performance degradation in the width direction 51 of the object to be measured, there is a method using illumination 83, 84, 85 having a certain extent and using an optical system such as a telecentric lens 89. Conceivable. According to this method, in the measured object width direction 51, the reflected light 86, 87, 88 is incident on the array sensor 81 in the vertical direction (FIG. 10B). However, the angle change information about the moving direction 50 of the object to be measured falls within the range of the spread of the incident light 83, 84, 85, and further greatly decreases, making it difficult to measure over a wide range (FIG. 10A). )). As described above, according to this apparatus using the two-dimensional array sensor, it is not possible to independently configure the shooting range in the moving direction and the width direction, and it is intended to obtain wide angle-of-change information in the moving direction of the object to be measured. Then, the measurement performance in the measured object width direction is deteriorated. Therefore, it is difficult to quantitatively evaluate wide angle information over a wide range, and watermark evaluation such as metallic coating cannot be performed.
[0009]
Next, the movement of the object to be measured will be considered with reference to FIG. For example, considering a case where a measurement object having a width of 1 m is measured using a two-dimensional array sensor having an aspect ratio of 1 in an imaging range, a 1 × 1 m image can be acquired by one imaging. However, this alone is only an image in which the light receiving angle of illumination is different for each position of the object to be measured, and it is necessary to move the object to be measured in order to obtain different angle change information for the same point. As shown in FIG. 11A, at this time, in order to obtain the angle change information of the maximum angle range, the object to be measured is approximately 1 m, which is a distance equal to the irradiation width 55, from the line 83 to the position of 85. Must move. Therefore, in order to obtain the maximum range of angle change information for the entire photographing range, it is necessary to move 3 m.
[0010]
Thus, in order to evaluate a wider range, the position for obtaining the deflection information is also relatively separated. The fact that they are relatively far apart is less problematic for devices equipped with a moving mechanism, etc., because it is relatively easy to synchronize the shooting cycle and movement, but it flows on the factory line where the line speed tends to fluctuate. The problem is great when measuring the measured object. That is, the fluctuation of the line speed becomes a deviation of the measurement position, and the angle change information at a different position of the object to be measured is acquired. Furthermore, when the imaging range is widened in order to realize evaluation in a wider range, it is assumed that the amount of movement of the object to be measured increases and the amount of fluctuation also increases. That is, it is difficult to deal with the factory line with these apparatuses alone, and in order to use this apparatus in the factory line, a separate facility for synchronizing the speed of the factory line and the timing of photographing is required.
[0011]
Further, at present, most of the two-dimensional array sensors used as photographing means are photographed at a general capturing speed of 1/60 seconds (16.7 msec / measurement) except for special ones. For this reason, in the case of a general factory line speed (60 m / min), the object to be measured moves 16.7 mm while taking in a continuous frame, and it is difficult to evaluate surface properties such as fine metal unevenness and metallic feeling. . Furthermore, when used in high-speed lines, it is more difficult and practical to use.
[0012]
[Problems to be solved by the invention]
Therefore, the technical problem to be solved by the present invention is that the surface texture that can independently configure the imaging range in the moving direction and the width direction, the number of angle information, the image capturing speed, and the moving speed of the object to be measured. It is to provide an evaluation device.
[0013]
[Means for solving the problems and actions / effects]
In order to solve the above technical problem, the present invention provides a surface texture evaluation apparatus having the following configuration.
[0014]
The surface texture evaluation apparatus includes a one-dimensional imaging unit that is arranged substantially perpendicular to the moving direction of the object to be measured and detects reflected light of the light irradiated on the object to be measured, and an incident angle with respect to the object to be measured. A plurality of illumination means for illuminating the surface of the object to be measured arranged differently, an illumination control means for switching the illumination means for illuminating the object to be measured in time series, and switched by the illumination control means Evaluation value calculation means for calculating an evaluation value corresponding to a reflection characteristic of the surface of the object to be measured with respect to a change in incidence of illumination light from a positional relationship between the illumination means for irradiating the object to be measured and the one-dimensional imaging means. Have.
[0015]
In the above configuration, a plurality of illumination means are arranged at high speed so that wide angle information can be obtained while freely setting the viewing angle of the one-dimensional imaging means considering the performance degradation in the width direction of the object to be measured. Switch blinking. In general, when a one-dimensional array sensor or the like is used as an imaging means, a high capture speed of about 1/20000 second can be easily realized. Therefore, since the angle change information can be acquired at high speed, there is no need to synchronize with the factory line speed, and color information and angle change information can be obtained even when measuring at a factory line where the line speed tends to fluctuate. It can be evaluated almost simultaneously.
[0016]
Therefore, according to the above configuration, the imaging range in the moving direction and the width direction of the object to be measured, the number of angle information, the capturing speed, and the moving speed of the object to be measured can be configured independently.
[0017]
Specifically, the surface texture evaluation apparatus of the present invention can be configured in various modes as follows.
[0018]
Preferably, the illumination means is a white LED.
[0019]
According to the above configuration, in the evaluation of color, glossiness, etc., it is possible to perform measurement with higher accuracy without being affected by the light color from the illumination means. Further, the LED can be switched on and off at high speed, so that an image can be captured at high speed when measuring an object to be measured.
[0020]
Preferably, the illumination means emits a linear light beam pattern.
[0021]
According to the said structure, the to-be-measured object can be measured over a wide range with a linear light ray.
[0022]
Preferably, the surface texture evaluation apparatus includes a telecentric optical system.
[0023]
According to the above configuration, since all the reflected light incident on the imaging means is incident as parallel light, the measurement performance can be improved without being affected by the angle in the measurement in the measured object width direction.
[0024]
The present invention further provides a surface texture evaluation apparatus having the following configuration.
[0025]
The surface texture evaluation device is arranged so that the illumination means for irradiating the surface of the object to be measured, and the reflected light of the light irradiated to the object to be measured from the illumination means, and the receiving angle of the reflected light is different. A plurality of one-dimensional imaging means, and an evaluation value calculating means for calculating an evaluation value corresponding to the reflection characteristic of the surface of the object to be measured with respect to the reception angle of the reflected light different from the positional relationship between the illumination means and the one-dimensional imaging means And have.
[0026]
In the above configuration, when the light emitted from the illumination unit is reflected by the object to be measured, a plurality of one-dimensional imaging units are arranged at positions where the reflection angles are different. Therefore, each one-dimensional imaging element receives reflected light having different light receiving angles at the same point, and a two-dimensional image of the reflected light is obtained by moving the object to be measured. Thus, an evaluation value corresponding to the reflection characteristic of the surface of the measurement object can be calculated.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a surface texture evaluation apparatus according to each embodiment of the present invention will be described with reference to the drawings.
[0028]
FIG. 1 is a schematic diagram showing the configuration of the surface texture evaluation apparatus according to the first embodiment of the present invention. (A) is a side view and (b) is a plan view. The surface texture evaluation apparatus 10 includes a one-dimensional linear array sensor (CCD linear camera) 15 disposed so that the light receiving angle is 45 degrees with respect to the normal direction of the measurement object 20, and the CCD linear camera 15. It has four white LED 11-14 which emits the linear light beam pattern arrange | positioned so that incident directions may each differ. The CCD linear camera 15 is arranged in a direction perpendicular to the moving direction 50 of the object to be measured 20 as shown in FIG. In the white LEDs 11 to 14, when the angle at which the received light is specularly reflected (Fresnel reflection) is 0 degree and the right side in FIG. 1A is the plus direction, the first LED 11 is 110 degrees, the second LED 12 is 45 degrees, and the third LED 13 Is arranged to be 15 degrees and the fourth LED 14 is 0 degrees.
[0029]
The CCD linear camera 15 and the LEDs 11 to 14 are controlled by a computer via the camera signal capturing unit 17 and the LED blinking switching control unit 16, respectively. As a result, the deflection information is obtained. The DUT 20 is fixed to the moving unit 21, and moves together when it moves in the moving direction 50. A two-dimensional image is acquired by continuously performing measurement with the CCD linear camera 15 while the object to be measured 20 moves. All of these pieces of information are transmitted to a computer and function as a data processing unit that calculates evaluation values such as color, glossiness, flop feeling, and metallic feeling using the obtained angle change information and outputs the results.
[0030]
FIG. 2 is a diagram for explaining a measurement method of the surface texture evaluation apparatus according to FIG. The surface texture evaluation apparatus is provided with four LEDs 11 to 14 that are arranged so that the light receiving angles are different from the reflected light 45 that is reflected by the object to be measured 20 and incident on the CCD linear camera 15. For example, the light 41 emitted from the first LED 11 is reflected by the object to be measured 20 and enters the CCD linear camera 15 as reflected light 45. The light receiving angle at this time is as indicated by reference numeral 31 in FIG. Similarly, the light 42 emitted from the second LED enters the CCD linear camera 15 at the light receiving angle 32. As described above, the surface texture evaluation apparatus can take information on different deflection information by switching the LED to be irradiated.
[0031]
On the other hand, with respect to the width direction 51 of the object to be measured, as shown in FIG. 2B, the influence of the angle information to be applied can be reduced by adjusting the viewing angle. That is, by reducing the viewing angle α, it is possible to reduce the influence β of the angle information generated in the reflected lights 46 and 48 at the ends of the visual field. Further, as described above, the angle-of-change information that can be obtained in the moving direction 50 of the object to be measured can be arbitrarily set according to the arrangement position of the LED. Is not reduced. Therefore, the viewing angle in the measured object width direction 51 can be freely set according to the size and characteristics of the measured object.
[0032]
FIG. 3 is a diagram showing a modification using a telecentric optical system. As shown in FIG. 3B, a telecentric lens 19 can be used as the telecentric optical system. Even when the telecentric lens 19 is used, the CCD linear camera 15 is not affected by the telecentric lens 19 because the CCD linear camera 15 does not have a viewing angle in the moving direction 50 of the measured object, as shown in FIG. There is nothing. On the other hand, the telecentric lens 19 allows the reflected light incident on the CCD linear camera 15 to be parallel light 46-48. Therefore, the imaging range in the measured object width direction 51 is reduced, but the influence of the angle β at the end of the imaging field of view can be minimized.
[0033]
Next, the flow of measurement processing of the surface texture evaluation apparatus according to the present embodiment will be described with reference to FIG. First, (1) the first LED 11 is turned on and one line is measured by the CCD linear camera 15. One-dimensional information of reflected light from the surface of the object to be measured is acquired as first variable angle data 61a. After data acquisition, the first LED is turned off. Next, (2) the second LED 12 is turned on and one line is measured by the CCD linear camera 15. One-dimensional information of reflected light from the surface of the object to be measured is acquired as second variable angle data 62a. After data acquisition, the second LED is turned off. (3) Similarly, the third LED 13 obtains the third variable angle data 63a and the fourth LED 14 acquires the fourth variable angle data 64a, and the acquisition of the data 60a in the first line is completed. (4) While moving the object to be measured (50a) by the moving unit, the above processing is repeated until the number of fetched lines is set arbitrarily, and data 60b, 60c to 60n in each line is acquired (FIG. 4). (A)). (5) When capturing up to a predetermined line is completed, the first to fourth variable angle data of each line is rearranged and displayed in the order of the acquired lines, thereby acquiring the respective variable angle images 61 to 64. That is, as shown in FIG. 4B, the first to fourth variation data is repeated, and a variation image is created by rearranging the data in which a predetermined number of lines are arranged for each variation data. That is, the first variable angle data 61a of the first line is moved to the first line of the first variable angle image 61, and the second variable angle data 62a of the first line is moved to the first line of the second variable angle image 62. Move to. Thereafter, similarly, a third variable angle image 63 and a fourth variable angle image 64 are created.
[0034]
Based on the first to fourth angle-changed images 61 to 64 obtained in this way, intensity three-dimensional distribution diagrams are created. FIG. 5 shows a three-dimensional intensity distribution diagram of an arbitrary variable angle image. The right horizontal axis indicates the visual field width direction, and indicates the position in the width direction of an arbitrary line of the CCD linear camera. The front vertical axis indicates the line direction and indicates the position in the moving direction obtained by moving the object to be measured. The vertical axis represents luminance, and when the CCD linear camera is a color camera, respective intensity distributions are created for the three elements of RGB. Based on the three-dimensional intensity distribution, unnecessary ranges are removed, and the following evaluation values (color, glossiness, flop feeling, metallic feeling) are calculated for each dot.
[0035]
In the present embodiment, the color calculation process of the object to be measured is performed using the three-dimensional distribution data of the second variable angle image. In the color calculation, color values, color unevenness, and color differences are calculated.
[0036]
First, the RGB value calculated for each dot is converted into a CIE XYZ value. Using the obtained XYZ values of each dot, the image is converted into a uniform color space such as a typical CIE LAB. Through the above processing, each dot (pixel) has a CIE LAB color value. For example, when the entire image has an enormous amount of color values, such as when the pixel resolution of a CCD linear camera is 1024 pixels and 1024 lines are measured, a specific range or even a specific color is selected as necessary. The number of data can be reduced by the averaging process such as, and the calculation processing time can be shortened. In this apparatus, since measurement is possible in a wide range, stable color measurement can be performed even for an object to be measured that cannot be stably measured by spot measurement, such as a metallic pattern.
[0037]
The color difference is calculated by comparing the color value obtained in each image with the color value of the reference image. Color unevenness is evaluated by dividing an image into a plurality of parts and comparing the divided parts. In other words, color unevenness can have various states, such as large overall occurrences or fine occurrences. Therefore, by changing the size of the area, the size of the color unevenness can be used as a decision factor. Additional evaluations can be made.
[0038]
In the present embodiment, the glossiness of the object to be measured is calculated using the three-dimensional distribution data of the fourth variable angle image. The glossiness is normalized based on the glossiness defined in JIS, and the entire image or a specific range, or a specific color is averaged as necessary as in the case of calculating the color value. The difference in gloss value is obtained by comparing the gloss value obtained in each image with the gloss value of the reference image. Further, gloss unevenness is evaluated using a method similar to that for color unevenness.
[0039]
For the feeling of flop, arithmetic processing is performed using the three-dimensional distribution data of the first to third variable angle images. The flop feeling is a geometric metamerism that appears different in hue, lightness, saturation, etc. depending on the angle change of incident light reception, and is calculated by a widely used flop evaluation formula. As in the color measurement, the calculation performs a wide range of flop measurements by averaging the flop values calculated for each dot within a specified range. Further, flop unevenness is evaluated by the same method as color unevenness.
[0040]
For metallic feeling, arithmetic processing is performed using the luminance change difference between the dots of the three-dimensional distribution data of the third variable angle image. An object to be measured having a metallic feeling tends to have a large luminance difference between dots, and becomes three-dimensional distribution data having a large difference in height.
[0041]
In addition, the contrast evaluation of the measured object printed by the same process, the unevenness of the measured object embossed or hulled, and the unevenness evaluation of paper or nonwoven fabric can also be performed.
[0042]
FIG. 6 is a schematic diagram showing the configuration of the surface texture evaluation apparatus according to the second embodiment of the present invention. (A) is a side view and (b) is a plan view. The surface texture evaluation apparatus 10a has substantially the same configuration as the apparatus according to FIG. The difference is that the DUT 20a continuously moves on the factory line 21a, and the same line is not measured in the first to fourth LEDs 11a to 14a. However, each of the first to fourth LEDs 11a to 14a blinks at a high speed every 1/2000 second, and the CCD linear camera can also take a picture at this timing. It can be kept low. In addition, since there is no relative relationship between the position of the measurement point and the angle change information, there is no influence on the angle change information even when the moving speed of the factory line 21 changes.
[0043]
FIG. 7 is a schematic diagram showing the configuration of the surface texture evaluation apparatus according to the third embodiment of the present invention. (A) is a side view and (b) is a plan view. The surface texture evaluation apparatus 10b includes a white LED 11b that emits a linear light beam pattern arranged so that a light receiving angle is 45 degrees with respect to a normal direction of the measurement target 20b, and light emitted from the white LED 11b. There are four CCD linear cameras 15b to 15e arranged so that the light receiving angles of the reflected light reflected by the measurement object 20b are different from each other. Each of the CCD linear cameras 15 b to 15 e is arranged in a direction perpendicular to the moving direction 50 of the object to be measured 20. Each of the linear cameras 15b to 15e has an angle of 0 degree as the specular reflection (Fresnel reflection) of incident light from the white LED 11b, and the right side in FIG. The second linear camera 15c is disposed at 45 degrees, the third linear camera 15d at 15 degrees, and the fourth linear camera 15e at 0 degrees.
[0044]
The CCD linear cameras 15b to 15e and the LED 11b are controlled by a computer via the camera signal capturing unit 17b and the LED lighting control unit 16b, respectively, and the CCD linears arranged at the above angles while the LED 11b is lit. Deflection information is acquired from images captured by the cameras. The DUT 20b is moved in the moving direction 50 by the moving unit 21b. A two-dimensional image is acquired by continuously performing measurements with the CCD linear cameras 15b to 15e while the object to be measured 20b moves. All of these pieces of information are transmitted to the computer 18b and function as a data processing unit that calculates evaluation values such as color, gloss, flop, and metallic feeling using the obtained angle-of-change information and outputs the result. About the process of a measurement, it is substantially the same as the surface property evaluation apparatus of FIG.
[0045]
With such a configuration, it is possible to directly create a variable angle image by each of the linear cameras 15b to 15e.
[0046]
As described above, the surface texture evaluation apparatus according to each embodiment includes a CCD linear camera that is disposed substantially perpendicular to the moving direction of the object to be measured and detects the reflected light of the light irradiated on the object to be measured; A plurality of LEDs that illuminate the surface of the object to be measured that are arranged so that the incident directions to the object to be measured are different from each other, and blinking while switching the plurality of LEDs, thereby obtaining an angle image having a plurality of angle information Can be created. Therefore, the imaging range in the moving direction and the width direction, the number of angle information, the image capturing speed, and the moving speed of the object to be measured can be configured independently.
[0047]
Also, an LED that irradiates the surface of the object to be measured, and a plurality of CCD linear cameras that are arranged so that the reflected light of the light emitted from the LED to the object to be measured is detected and the light receiving angles of the reflected light are different. Similarly, an angle image having a plurality of pieces of angle information can be created.
[0048]
In addition, this invention is not limited to the said embodiment, It can implement in another various aspect. For example, lighting means such as a flash that can be turned on / off at high speed may be used instead of LEDs, and a color camera is used by switching between red, green, and blue LEDs instead of white LEDs. The color can be evaluated.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a configuration of a surface texture evaluation apparatus according to a first embodiment of the present invention. (A) is a side view and (b) is a plan view.
FIG. 2 is a diagram for explaining a measurement method of the surface texture evaluation apparatus according to FIG. 1;
FIG. 3 is a diagram showing a modification using a telecentric optical system.
FIG. 4 is an explanatory diagram of measurement processing of the surface texture evaluation apparatus.
FIG. 5 shows a three-dimensional intensity distribution diagram of an arbitrary variable angle image.
FIG. 6 is a schematic view showing a configuration of a surface texture evaluation apparatus according to a second embodiment of the present invention. (A) is a side view and (b) is a plan view.
FIG. 7 is a schematic diagram showing a configuration of a surface texture evaluation apparatus according to a third embodiment of the present invention. (A) is a side view and (b) is a plan view.
FIG. 8 is an explanatory diagram showing a change in an emission angle of a conventional device having a wide viewing angle.
FIG. 9 is an explanatory diagram showing a change in an emission angle of a conventional device having a narrow viewing angle.
FIG. 10 is an explanatory diagram showing a change in an emission angle of a conventional apparatus using a telecentric lens.
FIG. 11 is a diagram for explaining a relationship between a moving speed and a distance of an object to be measured.
[Explanation of symbols]
10, 10a, 10b Surface texture evaluation device 11 First LED
12 Second LED
13 Third LED
14 4th LED
15, 15a, 15b to 15e CCD linear camera 16, 16a, 16b LED blinking switching control unit 17, 17a, 17b Camera signal capturing unit 20, 20a, 20b Measuring object 21, 21a, 21b Moving unit

Claims (4)

One-dimensional imaging means for detecting reflected light from one line on the object to be measured that is substantially perpendicular to the moving direction of the object to be measured among the reflected light of the light irradiated to the object to be measured;
When the reflected light from the object to be measured is received by specular reflection in the one-dimensional imaging means, the incident angle to the object to be measured is 0 degree, and the direction of the one-dimensional imaging means is a positive angle. A first illuminating unit, a second illuminating unit, a third illuminating unit, which are arranged so that incident angles with respect to the measured object are 110 degrees, 45 degrees, 15 degrees, and 0 degrees, respectively, and irradiate the surface of the measured object; A fourth lighting means;
Illumination control means for switching the first to fourth illumination means for irradiating the object to be measured in time series;
First to fourth variable angles constituted by arranging a predetermined number of lines of first to fourth variable angle data composed of one-dimensional information of reflected light from the object to be measured, corresponding to the first to fourth illumination means, respectively. Obtain three-dimensional distribution data of the intensity of the image, perform color calculation processing of the measurement object using the three-dimensional distribution data of the second variable angle image, and use the three-dimensional distribution data of the fourth variable angle image. The glossiness of the object to be measured is calculated, the flop feeling of the object to be measured is calculated using the three-dimensional distribution data of the first to third variable angle images, and the third variable angle image is calculated. Evaluation value calculation means for performing a calculation process of the metallic feeling of the measurement object using the three-dimensional distribution data of
A surface texture evaluation apparatus comprising:   2. The surface texture evaluation apparatus according to claim 1, wherein the illumination unit is a white LED.   3. The surface property evaluation apparatus according to claim 1, wherein the illumination unit emits a linear light beam pattern.   The surface texture evaluation apparatus according to claim 1, further comprising a telecentric optical system.

Images