JPH10160573A - Color measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain color distribution on a sample surface with irregularity. SOLUTION: By intermittently moving a sample table 21 in X-axis direction and simultaneously repeating spectrometry of the range in Y-axis direction with a light measuring component 10, color distribution on two-dimensional region on the upper surface of a sample 20 is provided. Next, by moving the sample table 21 under a distance measuring component 30, and by intermittently moving it in the X-axis or Y-axis direction during measuring distance, Z- coordinate of the surface of the sample 20 is provided. By comparing position data of the (X, Y, Z) coordinates with color distribution data, three-dimensional color distribution is calculated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color measuring apparatus for measuring the color of a sample using spectrophotometry.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram showing an example of a conventional color measuring apparatus for measuring the color of a sample surface. The color measuring device includes a photometric unit 10, a sample stage 21, a sample stage driving unit 22,
The photometric unit 10 includes an A / D conversion unit 23, an arithmetic processing unit 24, a control unit 25, and the like.
3, 16, a diffraction grating 14, a secondary light removal filter 15, and a photodetector 17.

The light emitted from the light source 11 is reflected by a one-dimensional region extending in the Y-axis direction of a sample 20 placed on a sample stage 21 and travels toward the slit 12. The light that has passed through the slit 12 is collimated by the lens 13 and
Secondary light removal filter 15 and lens 1
6 is projected onto a photodetector 17. Photodetector 17
Is a two-dimensional arrangement of a number of minute light receiving elements, and the position information in the one-dimensional region image of the sample 20 in the y-axis direction and the one-dimensional region image in the λ-axis direction orthogonal to the y-axis. The information on the spread of the wavelength at each position is obtained. That is, a spectral image indicating a spectral intensity distribution corresponding to a one-dimensional region image of the sample 20 in the Y-axis direction is obtained on the photodetector 17. This spectral image signal is converted into digital data by the A / D converter 23 and input to the arithmetic processor 24.

The sample stage 21 is intermittently moved in the X-axis direction by the sample stage driving unit 22 under the control of the control unit 25, and the spectral image of the one-dimensional area image of the sample 20 is sequentially and repeatedly measured as described above. You. Thus, spectral intensity distribution data for a two-dimensional region on the surface of the sample 20 is obtained. The arithmetic processing unit 24 calculates an index value (for example, chromaticity) for expressing a color for each minute area by performing arithmetic processing on the spectral intensity distribution data, and outputs the index value as two-dimensional color distribution data. Note that instead of moving the sample table 21 in the X-axis direction,
The same measurement can be performed even if the photometric unit 10 is configured to move in the X-axis direction with the sample stage 21 fixed.

[0005]

According to the apparatus having the above-described structure, an index value representing a color is calculated in each minute area in the two-dimensional area on the surface of the sample 20, so that the two-dimensional image of the sample 20 is obtained. Can be measured. However, it is not possible to measure the color distribution of a sample surface that is three-dimensionally deep. Suppose the sample stage 2 of the above device
When a sample having irregularities is placed on the sample and colorimetry is performed, the obtained color distribution is only a planar distribution with respect to a two-dimensional projected image of the upper surface of the sample. As is well known, human vision is capable of simultaneously recognizing three-dimensional information and color information of an object. Therefore, it is desirable to be able to measure the three-dimensional color distribution in order to accurately represent the color distribution on the surface of an object. . In particular, in the technical field of automatic recognition and evaluation of an object, measurement of a three-dimensional color distribution has been demanded in order to increase the accuracy of grasping the object.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a color measuring apparatus capable of measuring a color distribution of a surface having a three-dimensional area. Is to do.

[0007]

Means for Solving the Problems The color measuring apparatus according to the present invention, which has been made to solve the above-mentioned problems, comprises: a) color distribution information corresponding to a plane projection image of the entire sample or a partial region by spectroscopic measurement. B) position measuring means for measuring the spatial position information of the sample corresponding to the planar projection image, and c) having a three-dimensional area spread based on the color distribution information and the spatial position information. Processing means for calculating a color distribution on the surface of the sample.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a color measuring apparatus according to the present invention, a color measuring means measures a color distribution of a two-dimensional area corresponding to a projected image on the upper surface of a sample placed on a sample stage. The color measuring unit measures, for example, a two-dimensional spectral image by dispersing light reflected from a one-dimensional region of the sample in a two-dimensional (wavelength) direction by a spectral unit. The spectral image as described above is repeatedly obtained while relatively moving the sample stage and the photometry unit in a direction orthogonal to the one-dimensional region image, thereby obtaining spectral image data corresponding to the two-dimensional region image of the sample. The spectral image data is analyzed to obtain color information corresponding to each point (minute area) of the two-dimensional area image so as to obtain two-dimensional color distribution data. Another method for obtaining spectral image data corresponding to a two-dimensional region image of a sample is to project a projected image of the sample upper surface for each color by imaging means such as a CCD camera through wavelength switching means such as a wavelength switching filter. It may be obtained.

On the other hand, the position measuring means measures three-dimensional coordinate data (X, Y, Z) of the sample surface as spatial position information of the sample. The coordinates (X, Y) correspond to the two-dimensional projection plane on which the color measurement has been performed, and the Z coordinate corresponds to the depth of the sample. As the position measuring means, various methods can be used, such as a method of mechanically measuring a position by bringing a probe into light contact with a sample surface and a method of optically measuring a position without contact using a laser beam. . Based on the two-dimensional color distribution data and the three-dimensional coordinate data measured as described above, the processing means calculates and outputs the color distribution on the surface of the sample having the unevenness by appropriately associating the two data. The color measurement and the position measurement can be performed simultaneously or non-simultaneously.

[0010]

According to the color measuring apparatus of the present invention, it is possible to obtain a color distribution on the sample surface having a three-dimensional area. For this reason, it is possible to more accurately grasp the sample. Furthermore, by applying the color measurement device of the present invention to, for example, an automatic recognition or automatic evaluation device, it is possible to realize much higher processing than a conventional device.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a color measuring apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of the color measurement device of the present embodiment. Sample 20 placed on sample table 21
Photometry unit 1 for performing color measurement of a two-dimensional area on the upper surface
The configurations of the A / D converter 23 and the arithmetic processing unit 24 are the same as those shown in FIG. The apparatus of the present embodiment further includes a distance measuring unit 30 as a means for obtaining three-dimensional position information above the sample table 21. The distance measuring unit 30 is provided with an irradiation unit 31, a light receiving unit 32, and a distance calculating unit 33. It is configured. Further, the sample stage drive unit 40 is configured to horizontally move the sample stage 21 not only in the X-axis direction but also in the Y-axis direction under the control of the control unit 41. The three-dimensional coordinate calculation unit 42 receives the movement control information from the control unit 41 and the measurement result from the distance measurement unit 30, calculates three-dimensional coordinate data along the sample surface, and
Send to

Referring to FIG. 2, the operation of the color measuring apparatus having the above-described configuration when measuring the color of the sample 20 having irregularities as shown in FIG. 1 will be described. First, the control unit 41 sends a movement control signal to the sample stage drive unit 40, and moves the sample stage 21 directly below the photometry unit 10. And like the conventional device,
By repeatedly obtaining a spectral image with respect to the one-dimensional region image in the Y-axis direction on the upper surface of the sample 20 while intermittently moving the sample table 21 in the X-axis direction, spectral image data of a two-dimensional region image on the upper surface of the sample 20 is obtained. The arithmetic processing unit 24 calculates color distribution data for the two-dimensional region image based on the spectral image data. In other words, by this color measurement, distribution data of index values expressing colors on the projection plane above the sample 20 as shown in FIG. 2A is obtained. In FIG. 2A, one section is defined as one minute area on the (X, Y) coordinate plane, and an index value representing a color in each section is represented by shading of the color.

Next, the control unit 41 sends a movement control signal to the sample stage drive unit 40 to move the sample stage 21 directly below the distance measuring unit 30. Then, distance measurement is performed while the sample table 21 is intermittently moved in the X-axis and Y-axis directions. That is, the irradiation unit 3
The laser light is irradiated from 1 onto the sample 20 substantially along the Z-axis direction, and the light reflected by the surface of the sample 20 and returned is received by the light receiving unit 32. The distance calculation unit 33 measures the time from irradiation of the laser beam to reception of the reflected light, and calculates the distance from the distance measurement unit 30 to the surface of the sample 20 based on the measured value.

At the time of such distance measurement, the control unit 41 controls the movement of the sample table 21 so that each distance measurement point corresponds to each minute area of the two-dimensional color distribution. That is, the control is performed so that the distance measurement is performed at a position substantially at the center of one minute region in FIG. 3D coordinate calculator 4
Numeral 2 calculates the position of the ranging point indicated by the (X, Y) coordinate based on the movement control information, and based on the distance information given from the distance calculating unit 33, the Z based on the upper surface of the sample table 21 as a zero reference. The height of the surface of the sample 20 on the coordinates is calculated. This allows
(X, Y, Z) Position data along irregularities on the surface of the sample 20 expressed by three-dimensional coordinates is obtained. FIG. 2B shows position data on an XZ plane at a certain Y coordinate. That is, the value in the Z-axis direction indicates the height from the upper surface of the sample table 21 to the surface of the sample 20.

The synthesis processing section 43 receives two-dimensional color distribution data and three-dimensional position data. As mentioned above,
Each minute area of the two-dimensional color distribution data corresponds to each position on the (X, Y) coordinates of the three-dimensional position data. Therefore, the synthesis processing unit 43 obtains color information in association with the three-dimensional shape of the sample 20 based on these data. For example, three-dimensional (X, Y, Z) representing the surface shape of the sample 20
An index value representing a color is superimposed and displayed on a graph of coordinates, and this is displayed on a display screen. FIG.
FIG. 2C shows an example in which index values (in this example, shades of color) expressing colors are combined and expressed in the graph of FIG.
Of course, it is also possible to output numerical data as a table or the like in addition to the visual representation using a graph or the like.

FIG. 3 is a block diagram of a color measuring apparatus according to another embodiment of the present invention. In this color measurement device, the configuration of the photometry section is different from that of the previous embodiment. That is, in the color measurement device of this embodiment, the imaging illumination 50 irradiates the sample 20 placed on the sample stage 21 from obliquely above, and the entire image or a partial area image of the upper surface of the sample 20 is photographed by the CCD camera 51. Is done. Sample 20 and CCD camera 51
Between them, a switchable interference filter 52 is arranged as spectral means, and only reflected light of a specific wavelength determined by the filter is introduced into the CCD camera 51.
The image signal from the CCD camera 51 is converted to digital data by the A / D converter 23 and then sent to the arithmetic processing unit 53.

In this color measuring apparatus, the CCD camera 51 can be used without moving and scanning the sample table 21 or the photometric unit.
, One-time imaging, that is, data acquisition, obtains two-dimensional image data corresponding to a specific wavelength determined by the filter of the switchable interference filter 52. This two-dimensional image is an image corresponding to a specific wavelength in an imaging region on the upper surface of the sample 20. Then, the switchable interference filter 52 is rotated to obtain a plurality of two-dimensional images for different wavelengths, and the arithmetic processing unit 53 performs arithmetic processing on the data to calculate two-dimensional color distribution data.

In the above two embodiments, an optical non-contact type distance measuring unit is used to obtain the three-dimensional position of the sample. However, a contact type measuring unit may be used. For example, the probe is gently lowered from above with respect to the sample placed on the sample stage, and the lowering operation of the probe is stopped by detecting that the probe has contacted the sample surface. Then, it is preferable that the coordinates in the Z-axis direction are calculated based on the descending amount of the probe. Furthermore, if the photometry and the distance measurement can be performed at a position that does not hinder each other, the distance measurement and the photometry can be performed simultaneously, and the measurement time can be reduced.

The color measuring device of the present invention may be configured to perform the following operation. Usually, when a sample having large unevenness is irradiated with light from obliquely above, a shadow is produced. For example, even if a light source is arranged to irradiate light from almost the entire circumference, it is difficult to uniformly illuminate the sample surface. Therefore, first, three-dimensional position data on the sample surface is obtained by performing distance measurement. As a result, the state of unevenness on the surface of the sample can be grasped, so that an optimum or more preferable illumination state is obtained for a certain position on the surface based on the value of position data around the position. Then, the light emission amounts of a plurality of light sources arranged in the periphery are controlled respectively. That is, the light emission amount of each of the plurality of light sources is controlled so that shadows due to the surrounding convex portions are not easily formed. This makes it possible to make the light irradiation state almost uniform at any point on the sample surface.

The above embodiment is merely an example, and it is apparent that changes and modifications can be made as appropriate within the scope of the present invention.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of a color measurement device according to the present invention.

FIG. 2 is a schematic diagram for explaining a processing operation of the color measurement device according to the present invention.

FIG. 3 is a configuration diagram of another embodiment of the color measurement device according to the present invention.

FIG. 4 is a configuration diagram of a conventional color measurement device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Photometry part 20 ... Sample 21 ... Sample stand 30 ... Distance measuring part 31 ... Irradiation part 32 ... Light receiving part 33 ... Distance calculation part 42 ... Three-dimensional coordinate calculation part 43 ... Synthesis processing part

Claims (1)

[Claims] 1. a) color measurement means for measuring color distribution information corresponding to a plane projection image of the whole or a part of a sample by spectroscopic measurement; and b) measuring spatial position information of the sample corresponding to the plane projection image. A color measuring device that calculates a color distribution on a sample surface having a three-dimensional area based on the color distribution information and the spatial position information.