JPH09178565A - Color measuring system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure the color efficiently while saving the time and labor depending on the purpose. SOLUTION: Prior to starting spectrometry, total image of a sample 2 is picked up by means of a CCD camera 31 and the RGB value distribution data of image signal is stored in an RGB value memory 34. Based on the distribution data, a control section 35 detects the region of the same color, for example, in response to the designation from an input section 36. A control signal is delivered to a motor drive section 37 such that only the region of the same color is subjected to spectrometry and a sample stage 1 is set at a specified position along with a spectrometric unit 10. Since only the required region of a sample is subjected to spectrometry depending on the purpose, the time required for operating the chromaticity from a spectral intensity distribution data, as well as the time of spectrometry, can be shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color measuring device for measuring the color of a sample surface by utilizing spectrophotometry.

[0002]

2. Description of the Related Art FIG. 5 is a schematic block diagram of a color measuring device for measuring the color of a two-dimensional area of a sample. Light source 1
The light emitted from the sample 1 is the sample 2 placed on the sample table 1.
Is reflected by a one-dimensional region extending in the Y-axis direction toward the slit 12. The light passing through the slit 12 is collimated by the lens 13, dispersed by the diffraction grating 14, and then projected onto the photodetector 17 via the secondary light removal filter 15 and the lens 16. The photodetector 17 has a large number of minute light receiving elements arranged two-dimensionally, and the positional information in the one-dimensional region of the sample 2 is arranged in the y-axis direction, and in the λ-axis direction orthogonal to the y-axis. Information on the wavelength spread at each position in the one-dimensional region can be obtained. That is, a spectral image showing the spectral intensity distribution corresponding to the one-dimensional region of the sample 2 is obtained on the photodetector 17.

A photometric unit 1 including a light source 11 and the like
0 is intermittently moved in the X-axis direction by the motor, and the spectral intensity distribution in the two-dimensional region is obtained by sequentially and repeatedly measuring the spectral images in the one-dimensional region as described above. The spectral intensity distribution data is calculated by a calculation personal computer (personal computer) 20 to obtain the chromaticity of each minute area, and the result is displayed on the screen of the display 21 or printed out from the printer 22. The same measurement can be performed even if the photometric unit 10 is fixed and the sample table 1 is movable in the X-axis direction.

[0004]

According to the apparatus having the above-mentioned structure, the chromaticity in each minute region on the sample surface can be precisely calculated, but on the other hand, it takes a long time for spectroscopic measurement and an enormous amount of spectrum. The calculation also requires a considerable amount of time to process the intensity distribution data. In the color measurement, it is not always necessary to have a detailed chromaticity distribution over the entire sample surface, and for example, comparing chromaticities of a plurality of regions having similar colors, or comparing a plurality of regions having substantially the same color In many cases, the purpose is to calculate the average value of chromaticity. Even in such a case,
Conventionally, there is a problem in that the efficiency of measurement is poor because the calculation for obtaining the necessary value is performed after obtaining the detailed chromaticity distribution of the entire sample.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a color measuring apparatus capable of performing efficient measurement in accordance with the measurement purpose.

[0006]

SUMMARY OF THE INVENTION The present invention, which was conceived to solve the above-mentioned problems, provides a color measuring apparatus for spectroscopically measuring a sample placed on a sample table and performing color measurement based on the spectroscopic measurement result. In a), a) an image pickup means for picking up an image of the whole or a partial area of the sample, and b) storing the distribution of signals expressing the color of the image captured by the image pickup means in association with the position on the sample surface. A storage means for determining the position and / or size of the region to be spectroscopically measured based on the signal stored in the storage means, and d) the sample stage or the spectroscopic measurement. And a drive means for driving the moving means in accordance with the result of the determining means, the moving means for relatively moving the photometric section for performing relative movement in the horizontal direction and / or the vertical direction. I am trying.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a color measuring apparatus according to the present invention,
A sample image is photographed by an image pickup means such as a CCD camera prior to the spectroscopic measurement, and signals representing the colors for each pixel of the CCD camera are represented by, for example, three primary colors of red (R), green (G), and blue (B). (2) The two-dimensional distribution of RGB values separated into (1) is stored in the storage means. At this time, since the range of the sample surface photographed by the CCD camera is known, the correspondence between the RGB value distribution stored in the storage means and the position on the sample surface is established. Based on this RGB value distribution, appropriate measurement positions and measurement region sizes are determined according to the purpose of measurement.

For example, when it is desired to make a detailed comparison of the chromaticity of a plurality of regions having similar colors on the sample surface, the determining means is
A region having a similar color on the sample surface is determined from the distribution of RGB values, and the position of the region on the sample surface (for example, the coordinate position of the sample table) is instructed to the driving means. The driving means controls the moving means according to this instruction so that the photometric unit and the sample have a predetermined positional relationship. As a result, only the region having a similar color on the sample surface is sequentially spectroscopically measured. Therefore, spectroscopic measurement can be performed in a short time because only the necessary region corresponding to the measurement purpose is spectroscopically measured. Also, since the spectral intensity distribution data is small, the chromaticity can be calculated at high speed.

In addition to the above, it is possible to judge the color distribution on the sample surface from the distribution of RGB values in advance and perform various automatic measurements. In particular, not only can the photometric unit and the sample be moved horizontally relative to each other, but a mechanism for changing the distance between them can be added to automatically adjust the size of the spectroscopic measurement area. By doing so, advanced automatic measurement can be performed.

[0010]

As described above, according to the color measuring apparatus of the present invention, the position and size of the measurement area are automatically set based on the color distribution simply obtained using the image pickup means. In addition, the detailed spectroscopic measurement of the entire sample is not required, and the measurement time can be significantly shortened. In addition, since it is not necessary to manually perform position adjustment while visually checking,
Not only does it save time, but the measurement accuracy is improved. Of course, the distribution data of the RBG value or the photographed color image can be used as a reference material for simply grasping the color distribution of the sample.

[0011]

Embodiments of the color measuring apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of this color measuring device, and the configuration inside the photometric unit 10 is the same as that shown in FIG. The CCD imaging illumination 30 illuminates the surface of the sample 2 obliquely from above, and the CCD camera 31 captures the entire image or partial region image of the sample 2. The image signal is sent to the image signal processing unit 32, and is subjected to processing such as noise removal, edge enhancement, and color correction, and then the display 3
3 is displayed on the screen. In the image signal processing unit 32, the R, G, and B independent signals are separated from the image signal corresponding to each pixel of the CCD camera 31 (or the signal after the above-described processing), and one frame is separated. The RGB value distribution of is stored in the RGB value memory 34 as digital data. This data is stored in the control unit 3 including a CPU and the like.
In accordance with the address designation from 5, the RGB value memory 34 is appropriately read and input to the control unit 35.

In the control unit 35, as will be described later, the input unit 3
The RGB value data is determined by 6 according to the instruction given by the operator, and a control signal is sent to the motor drive unit 37. The sample stage 1 is controlled by the X-axis direction motor 38, the Y-axis direction motor 39, and the Z-axis direction motor 40 so that X, Y, Z
It is possible to move in three dimensions. That is, the X-axis direction motor 38 and the Y-axis direction motor 39 can move an arbitrary position on the sample 2 directly below the photometric unit 10, and the Z-axis direction motor 40 can change the size of the region to be measured. it can. In addition, the personal computer 2 in the input unit 36
A keyboard of 0 can be used, and the display 33 and the display 21 may be combined.

In executing the color measurement, first, the operator places the sample 2 to be measured on the sample table 1 and then CC
Adjust the zoom of D-camera 31 appropriately and display 3
The whole image of the sample 2 is displayed on the screen of 3.
If the purpose is to measure only within the range of a partial region of the sample 2, it is sufficient to adjust the zoom so that the entire range of the region is displayed on the screen of the display 33. When the zoom adjustment is completed, the operator operates the keys of the input unit 36 to instruct "image memory". When the control unit 35 receives this instruction, CC
RG that separated the image signal sent from the D camera 31
The data obtained by digitizing the tristimulus values of B is stored in the RGB value memory 34. In order to spectroscopically measure a desired position in one frame image in the RGB value memory 34,
It is necessary to know the correspondence between the address position in this one-frame image and the position on the sample 2. This can be realized by the following method, for example.

FIG. 2 is a diagram virtually showing a memory space of the RGB value memory 34. The memory 34 stores a main memory unit 50 having a memory element corresponding to each pixel of the CCD camera 31 that spreads two-dimensionally, and a coordinate position in the X-axis direction corresponding to each vertical memory element of the main memory unit 50. And a Y-coordinate memory unit 52 for storing the coordinate position in the Y-axis direction corresponding to each memory element in the horizontal direction of the main memory unit 50. Each memory element of the main memory unit 50 has a depth for storing the RGB tristimulus values of each pixel.

When data is stored in the RGB value memory 34, one frame of data supplied from the image signal processing unit 32 is stored in the main memory unit 50 as it is. CC
Since the position taken by the D camera 31 is predetermined, it depends on the position of the sample table 1 in the X-axis direction and the Y-axis direction at the time of shooting and the zoom position of the CCD camera 31.
The coordinate position in the X-axis direction and the Y-axis direction of the area being photographed can be detected. For example, the coordinates are based on the minimum resolution of spectroscopic measurement. In this case, assuming that the minimum resolution of the spectroscopic measurement and the pixel unit of the CCD camera 31 match, one unit of the memory address of the main memory unit 50 becomes one unit of coordinates. The coordinates detected as described above are stored in the X-coordinate memory unit 51 and the Y-coordinate memory unit 52. Therefore, by reading the contents of the X-coordinate memory unit 51 and the Y-coordinate memory unit 52, the coordinates in the X-axis direction and the Y-axis direction corresponding to an arbitrary address position in the main memory unit 50 can be directly obtained.

The correspondence between the address position of the RGB value memory 34 and the position on the sample 2 can also be obtained by the following method. In this method, as shown in FIG. 3, a memory space 53 that two-dimensionally expands corresponding to the coordinates in the X-axis direction and the Y-axis direction of the entire range that can be measured by horizontally moving the sample table 1. Is prepared.
In this memory space 53, each data is stored at the address position directly corresponding to each coordinate of the area photographed by the CCD camera 31. That is, as shown in FIG. 3, the data distribution 54 corresponding to the area image photographed by the CCD camera 31.
Are formed in the memory space 53. Therefore, when only a very small area of the sample 2 is photographed by the zoom of the CCD camera 31, the memory area where the data is actually stored is limited to a very small area of the memory space 53. Become.

Various automatic measurements can be performed using the data stored in the RGB value memory 34 as described above. Hereinafter, an example will be described. When a plurality of color regions are intricately intricately mixed on the sample 2 and it is desired to compare the colors of a plurality of regions of almost the same color in detail, a plurality of regions having similar colors are automatically searched for, Chromaticity can be calculated and compared. When performing such a measurement, first, the operator sets the color to be compared in advance from the input unit 36. At this time, the setting may be made by a numerical value such as chromaticity, or a plurality of color samples may be selected. In the control unit 35, R
The data stored in the GB value memory 34 is sequentially read, and it is determined whether or not the color is a set color or a color close to it, and the area of the same color is detected.

For example, in one frame image 60 as shown in FIG. 4, it is assumed that the shaded areas 61 and 62 have the same color. Then, the region for spectroscopic measurement is determined from the range of the spread of the same color. That is, measurement regions 63 and 64 surrounded by horizontal windows in the vertical and horizontal directions are set for the regions 61 and 62 of the same color, and the coordinates in the X-axis direction and the Y-axis direction corresponding to the measurement regions are set. Ask. Further, based on these coordinates, the amount of movement in the X-axis direction and the Y-axis direction from the current position of the sample stage 1 is calculated. The amount of movement in the Z-axis direction is also calculated according to the size of the measurement area. Then, these movement amounts are given to the motor drive unit 37 as control signals. The motor drive unit 37 uses the motors 38, 39, so that the one-dimensional region in the Y-axis direction having the smallest coordinate in the X-axis direction can be spectroscopically measured in the measurement region having the smallest movement amount in the X-axis direction or the Y-axis direction.
40 are controlled respectively. As a result, the sample table 1 and the photometric unit 10 are set at predetermined positions.

When the spectroscopic measurement of the one-dimensional region is completed, X
The sample motor 1 is moved by the axial motor 38 so that the adjacent one-dimensional region is spectroscopically measured, and this is repeated to complete the two-dimensional spectroscopic measurement in the measurement region. Then
The motor drive unit 37 moves the sample table 1 to measure another measurement area. By repeating the above operation, the spectroscopic measurement is completed for all the measurement regions instructed by the control unit 35, and the chromaticity is calculated based on the spectral intensity distribution data obtained by the spectroscopic measurement.

As described above, the following measurement can be performed by detecting a plurality of areas having the same color or similar colors. (1) An average value of chromaticity of a plurality of areas having the same color or similar colors is calculated. (2) The measurement of the same color area portion is omitted, and only the different color portion is measured.

In the above description, the color measuring device is performed by using the spectroscopic measurement in the two-dimensional area.
It can also be applied to a device that calculates chromaticity based on the result of spot-wise spectroscopic measurement of a point on the surface of. In such an apparatus, since the size of the spot to be spectroscopically measured is changed by moving the sample table 1 in the Z-axis direction, if the spot diameter is increased, the average chromaticity in a wide area is obtained, and conversely. If the spot diameter is reduced, the chromaticity of a fine area can be obtained. Further, if a mask having an appropriate shape is inserted in the optical system between the sample 2 and the photometric unit 10, it is possible to perform spectroscopic measurement of measurement areas of various shapes.

In any of the above embodiments,
Instead of moving the sample table 1, the sample table 1 may be fixed and the photometric unit 10 may be moved.

[Brief description of the drawings]

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

FIG. 2 is a schematic diagram virtually showing a memory space of an RGB value memory.

FIG. 3 is a schematic diagram for explaining another configuration of an RGB value memory.

FIG. 4 is a schematic diagram showing an example of data stored in an RGB value memory.

FIG. 5 is a configuration diagram of a conventional color measuring device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Sample stand 2 ... Sample 10 ... Photometric unit 31 ... CCD camera 32 ... Image signal processing unit 33 ... Display 34 ... RGB value memory 35 ... Control unit 36 ... Input unit 37 ... Motor drive unit 38 ... X-axis direction motor 39 ... Y-axis direction motor 40 ... Z-axis direction motor

Claims (1)

[Claims] 1. A color measuring device for spectroscopically measuring a sample placed on a sample stage and performing color measurement based on the spectroscopic measurement result, comprising: a) imaging for imaging an entire or partial region of the sample. Means, b) storage means for storing the distribution of signals representing the color of the image captured by the imaging means in association with the position on the sample surface, and c) signals stored in the storage means. The position of the region to be spectroscopically measured and / or the size of the region based on the above, and d) the sample stage or the photometric unit for performing the spectroscopic measurement in a horizontal and / or vertical direction relative to each other. A color measuring device comprising: a moving means for moving; and e) a driving means for driving the moving means according to a result of the determining means.