JPH0477633A - Colorimeter - Google Patents

Abstract

PURPOSE:To make it possible to perform the simple, instantaneous measurement of color sensation in metallic painting and the like by arbitrarily selecting an incident angle and a light receiving angle in the vertical direction with respect to the surface of a sample, measuring the values of colorimetry in various kinds of incident and light-receiving-angle conditions. CONSTITUTION:A fixing jig 7 has a semicircle ring shape. The center of the ring is the center of a measuring hole 3 of an outer case 11. The jig 7 is located on a plane including a normal line 4 within the surface which is orthogonal to a sample 1. Attaching holes 7a for attaching photodetectors 6a, 6b and 6c and a light source device 5 are formed at 11 places so that the holes are directed toward the center of the hole 3 at every 15 deg. to the right and left with the normal line 4 as a reference. The parallel luminous flux is emitted from the light source device 5 on the sample 1. The reflected light is received with the photodetectors 6a, 6b and 6c at the same time. The signal are guided into an operating device 10 through an A/D converter 8 and an amplifier 9. The value of colorimetry at the position of each photodetector is computed, and the color difference between the photodetectors is obtained. Thus, the color sensations in painting and the like are measured simply and quickly.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is a colorimeter that easily and instantly measures the color appearance of metallic paints used as high-grade paints on the surfaces of industrial products, especially automobiles, home appliances, etc. Regarding.

[Prior art and its problems] In the coating of automobiles, home appliances, etc., as the demand for beautiful finishes and high-class finishes increases, improvements and developments in metallic coatings, pearl coatings, etc. are progressing.

These coatings have specular reflections from the clear top coat on the surface, specular reflections from the metallic base coat which is colored with aluminum pieces and mica on the bottom, and
In addition to the usual gloss and smoothness, diffused light and other elements intertwine in a complex manner to give a sense of brilliance, depth, transparency, color, etc., and these vary depending on the angle of incidence of the light or the angle of the viewing eye. It is designed to enhance the beauty and luxury of the coating.

However, the color evaluation of these painted products has traditionally been done by visual inspection (visual evaluation) by skilled engineers, which has drawbacks such as large differences in evaluation and time-consuming. A new management (evaluation) method was needed.

As a numerical control method, a variable angle colorimeter, which measures color while changing the incident angle and acceptance angle, has come to be used. A typical example thereof is the device disclosed in Japanese Patent Application Laid-Open No. 159031/1983. FIG. 5 is a perspective view of the main parts of this device.

In this device, a sample stage 25 that can be rotated in a vertical direction and a light receiver 26 that can be rotated horizontally around this sample stage 25 are arranged in a dark box 27, and a sample holder fixed to the sample stage 25 is placed in a dark box 27. The light source device 28 is configured to emit light from the light source device 28. Therefore, the vertical and horizontal angles with respect to the incident light can be arbitrarily set.

However, in this method, the color of sample 1 is measured at each specific incident angle and acceptance angle, and the obtained colorimetric values are calculated sequentially to calculate the color difference of the angle division, which is a complicated and time-consuming operation. This was the case.

In addition, since the sample 1 is measured in the dark box 27, the size of the sample 1 is limited, making it impossible to measure large samples or real samples, and making it impossible to use it at painting sites, production lines, etc.

[Means for Solving the Problems and Their Effects] According to the present invention, (1) In a colorimeter that measures the triangular intensity values X, Y, and Z from reflected light from the sample, the sample surface is incident (irradiated). A light source device that can set the incident angle to the sample surface arbitrarily and a light source device that can set the incident angle to the sample surface arbitrarily on a plane perpendicular to the sample surface that contacts the opening, and The method was constructed by installing a plurality of light receivers that can be arbitrarily set at different light receiving angles, and further providing an arithmetic processing unit to process the output signals from these individual light receivers. The incident angle and light reception angle can be arbitrarily selected in the vertical direction, and colorimetric values under various incidence and light reception angle conditions can be measured simultaneously, and color differences between different light reception angle conditions can be determined simultaneously.

(2) In addition to (1), when a sample is placed with the sample surface in contact with the aperture to be measured, a rotating sample that rotates around the intersection of a plane perpendicular to the sample surface and the sample surface. In addition to the effect of (1), in addition to the effect of (1), the method includes a table and a dark box that covers this opening and the entire rotating sample table and blocks external light.
The direction of the sample surface held on the rotating sample stage can be arbitrarily set with respect to the incident angle and the light receiving angle.

(3) In addition to (1), a sample stage that rotates around the center of the aperture is arranged closely to the aperture for measuring the sample surface, and the surface in contact with the sample is a magnetic specimen. By using this as a means, in addition to the effect of (1), the colorimeter (or sample) can be rotated to any position while keeping the sample stage in close contact with the sample surface.

(4) In addition, in a colorimeter that measures the three emissive values X, Y, and Z from the reflected light of the sample, it is located inside a box with an opening for incident (irradiating) the sample surface. A light source device that can arbitrarily set the incident angle to the sample surface and multiple light receivers that can arbitrarily set the reflected light from the sample surface at different reception angles are installed on a plane perpendicular to the sample surface. , further provided with an arithmetic processing unit for processing the output signals from these individual light receivers, and a large and small circle located within the box body and close to the opening and rotating around the center of the opening. Annular rotary disks are arranged in sliding contact with each other so that they can rotate,
The mounting jig for the light source device was fixed to a small rotary disk, and the mounting jigs for the plurality of light receivers were fixed to a large rotary disk, so that it was possible to prevent the incidence of light in the vertical and horizontal directions with respect to the sample surface. The angle and the reception angle can be selected arbitrarily, and the colorimetric values under various incident and reception angle conditions can be measured simultaneously, and the sample surface can be measured three-dimensionally without moving the sample. This means that the color difference can be determined at the same time.

[Example〕 Hereinafter, the present invention will be explained in detail using the drawings.

First Embodiment FIG. 1 is a block diagram showing a first embodiment. In the figure,
1 is a sample, 2 is a sample stage on which the sample is placed or in contact with it, 3 is a measurement aperture, 4 is a normal line passing through the center of the measurement aperture and perpendicular to the surface of the sample 1, 5 is a light source device, 6a 6b, 6c are light receivers, 7 is a fixture for the light receiver and light source device, 8 is an A/D converter, 9 is an amplifier, 1° is an arithmetic processing unit, and 11 is an exterior case.

The fixing jig 7 is located inside the case 11 and is a semicircular ring centered on the center of the measurement aperture 3, located on a plane including the normal line 4, and has both ends fixed inside the case 11. Furthermore, the light receivers 5a and 6b are directed towards the center of the measurement aperture 3 in 15° increments to the left and right with respect to the normal line 4 as a reference.

6c and the mounting hole 7a for attaching the light source device 5 to 11.
It is open in several places.

Although the light source device 5 is not shown in detail, it has a known configuration consisting of a xenon flash lamp, a group of lenses, etc. in order to irradiate the sample 1 with a parallel beam of light, and is fitted into the mounting hole 7a at a position of 145 degrees from the normal line 4. The center axis of this parallel light beam is fixed with a knurled screw (not shown) in a positional relationship where it intersects with the normal line 4 on the surface of the sample.

The light receivers 6a, 6b, and 6c have the same performance, and receive the reflected light irradiated onto the sample 1 from the light source device 5. Although not shown in detail, the light receivers 6a, 6b, and 6c have the same performance. It has a known configuration consisting of a extreme value filter and three light receiving elements corresponding to each filter, and is fitted and fixed in the mounting holes 7a at 150 and 60 degrees from the normal line 4 in the same way as the light source device 5. It is.

Further, each of the light receiving elements of the light receivers 6a, 6b, and 6c is connected to an arithmetic processing unit 10 having an arithmetic circuit for each light receiver via an A/D converter 8 and an amplifier 9, respectively.

Now, in the apparatus of the first experimental example configured as described above, a parallel light beam is irradiated from the light source device 5 to the sample 1 in contact with the sample stage 2, and this reflected light is sent to the light receiver 5a.

6b and 6c receive light at the same time, and each A/
The signal is photoelectrically converted by a D converter 8 and guided to an arithmetic processing unit 10 via an amplifier 9. Here, the colorimetric value at the position of each light receiver is calculated, and the color difference between the light receivers, for example, between the light receivers 6a and 6c located at 115 degrees and 60 degrees with respect to the normal 4 is determined. .

The light source device 5 and the light receivers 6a, 6b, and 6c can be mounted at any position in the mounting holes 7a provided in the fixture 7, and the angles of the mounting holes 7a with respect to the normal 4 are set in 15° increments. It is not limited.

Second example FIG. 2 is a perspective view of essential parts showing a second embodiment.

In the figure, in this embodiment, a rotary sample stage 12 is attached to the sample stage 2 in the first embodiment.

The rotating sample stage 12 has a disc shape smaller than the circle inscribed in the measurement aperture 3, and when it is placed parallel to the measurement aperture 3, it is aligned with the central axis of the parallel light beam irradiated from the light source device 5 (see Fig. 1). A rotating shaft 13 is fixed to the rotating sample stage 12 and rotates about an intersection line between the rotating sample stage 12 and a plane that includes a straight line passing through the center of the measurement aperture 3 and perpendicular to the rotating sample stage 12.

Further, this rotating shaft 13 is supported by a rotating shaft stopper 14 fixed to the sample stage 2, and although not shown in detail, the rotating sample stage 12 can be fixed at any angle.

Further, in order to block external light during measurement, a dark box 15 that covers the entire sample stage 2 and rotary sample stage 12 is removably provided.

Note that the sample 1 is, in principle, a flat plate-like object, and is of a size that does not protrude from the rotating sample stage 12.

Now, the apparatus of the second embodiment configured as described above can rotate and fix the sample attached to the rotating sample stage 12 at any arbitrary angle around the rotation axis, and in addition to the function of the first embodiment, the sample can be fixed at any angle. The colorimetric value at the position of each light receiver is calculated while the light receiver is tilted at an angle of , and the color difference between the light receivers is determined.

Third embodiment FIG. 3 is a perspective view of essential parts showing a third embodiment.

In the figure, in this embodiment, the sample stage 2 in the first embodiment is replaced with a rotating disk-shaped sample stage 16.

In the figure, a rotating disk-shaped sample stage 16 is constructed by combining two disks each having an opening of the same diameter in the center so that the centers of the openings coincide and are mutually rotatable. The fixed portion 16a is fixed to the outside of the case 11 so as to coincide with the center of the disk, and the other disk is used as a rotating portion 16b. In addition, a magnetic rubber 17 is pasted as a magnetic elastic body on the surface of the rotating part 16b that comes into contact with the sample, and the fixed part 1
An angle scale 18 indicating the rotation angle of the rotating portion 16b is attached to the side surface of the rotating portion 6a.

Now, the apparatus of the third embodiment configured as described above has the function of the rotating part 16b of the sample stage 16 in addition to the function of the apparatus of the first embodiment.
Since the sample can be closely fixed by the magnetic material, the colorimetric position on the sample surface can be changed arbitrarily by rotating either the sample or the device while leaving the sample or device in the same state.

Fourth example FIG. 4 is a perspective view of essential parts showing a fourth embodiment.

In the figure, this embodiment shows a light source device 5 and a plurality of light receivers 6.
In order to fix the mounting jig, a rotating annular disk 20 is constructed by slidingly contacting large and small annular disks 19a and 19b having the same center as the center of the measurement opening 3 in a stepped manner and rotatable with each other. A small annular disk 19a is arranged within the case 11 on the surface having the measurement opening 3.

The light source device mounting jig 21 for attaching the light source device 5 is
It is a combination of two semicircular plates of the same shape parallel to each other with a constant interval between them, and the plane containing the normal 4 (see Figure 1) is located so that it passes through the center of this interval, and is fixed to the small annular disk 19a. Here, the light source device 5 is inserted into the space between the jig 21 so that the center of the irradiated light beam coincides with the center of the measurement aperture 3, and is fixed with a knurled screw (not shown) or the like. Furthermore, on the side surface of the semicircular plate forming this jig 21, there is a
An angle scale 18 is attached.

The light receiver mounting jig 22 for mounting a plurality of light receivers 6 has a semicircular shape, and its center is on the same plane as the plane passing through the center of the interval between the light source device mounting jig 21, and both ends are formed into a large ring shape. It is fixed to the board 19b. Therefore, all of the light receivers 6 are located outside the light source device 5. Moreover, each light receiver 6 is
The jig 22 is fixed to the light receiver mounting holes 23 provided at 15 degree intervals with respect to the normal line 4 so as to face the center of the measurement aperture 3 in the same manner as the light source device 5.

Further, the interval between the two semicircular plates constituting the light source device mounting jig 21 is wider than the width of the light receiver mounting jig 22, and is sufficient for the reflected light from the sample surface to reach each light receiver 6. It has a wide width.

Further, each of the large and small annular disks 19a, 19b has an angle scale 18 in 1 degree increments on the circumferential side thereof. Further, in order to make the scale 18 easily visible and adjustable, a notch 24 is provided in a part of the case 11, and an index (not shown) is attached thereto.

Note that each light receiver 6 is the light receiver 6a, 6b, 6c of the first embodiment.
Like these, each light receiver is connected to an arithmetic processing unit having an arithmetic circuit through an A/D converter and an amplifier (not shown).

In the device of this embodiment configured in this way, a light source device mounting jig and a light receiver mounting jig are respectively attached to the rotating toric disc, which is configured in a stepped manner by making large and small annular plates rotatably in sliding contact with each other. By attaching them, the light source device and the light receiver can be positioned at arbitrary angles in the horizontal direction with respect to the sample placed on or in contact with the sample stage. Furthermore, since the light source device 5 can be attached to the fixture so as to be movable at a predetermined angle,
The sample can be irradiated from any vertical angle. For example, as in this embodiment, the light receiver is attached to the light receiver mounting fixture 22.
Since the light receivers 6 are installed at 11 locations in 5-degree increments, the reflected light can be measured simultaneously by these light receivers 6, and the color difference between the light receivers can be determined. (However, the light receiver located on the straight line connecting the light source device and the center of the sample aperture 3 is excluded.) Therefore, the color of the sample surface can be measured three-dimensionally without moving the sample. It is also possible to obtain color differences at the same time.

[Effects] Next, measurement results using the apparatus of the first embodiment of the present invention will be explained.

The samples were four types of metallic paint that differed only in the red content of bright material (aluminum powder) on the iron material (A, B, C, and D had the highest amount of aluminum powder in that order), and this. In order to compare with the red metallic coating, we used the same material (E) with a red coating (solid coating) except for the glitter material.

Further, the measurement conditions were that the incident angle was 45° and the light receiving angle was two angles of -15° and 600° with respect to the normal to the sample surface. In addition, in this device, the three energy extreme values X,
Various color display methods are possible from Y and Z, but here we will use the L'a″b° color system (described in JIS28730, etc.)
Find the value of L"a"bo and the value of △E"ab, and
Shown in the table.

Table 1 In A-D in Table 1, △E″ab represents the color difference as well as the directionality of the color sense between -15° and 60° angles, and Lo represents the intensity of brilliance. Therefore, △E' The larger the numbers for both ab and L'', the more the color direction of the metallic paint,
This means that the color has strong transparency, depth, and color saturation.
It can be seen that in metallic coatings, if the content of the glittering material (aluminum powder) changes, the color, transparency, depth, etc. will also change.

It can be seen that there is a significant difference in color direction, transparency, depth, saturation, etc. between the solid coating (E) and the metallic coatings (A to D).

In addition, although the measurement results are not shown for the apparatuses of the second to fourth embodiments, the measurement angle of the sample in the vertical or horizontal direction can be easily measured using a modified sample stage of the apparatus of the first embodiment. By adding measurement conditions, it is possible to more closely approximate the angle of the actual viewing eye.

As is clear from the above, with the apparatus of the present invention, it is possible to numerically represent the difference in metallic coating etc. depending on the viewing angle.

Further, except for claim 2 (apparatus of the second embodiment), unlike conventional apparatuses, it is not necessary to measure the sample in a dark box, so that the apparatus can be directly applied to the sample for measurement.

Therefore, even the exterior of large samples such as automobiles can be directly measured. Furthermore, since the color at each angle can be represented numerically as described above, numerical management is easily possible, individual differences due to visual perception evaluation are eliminated, and the time required for determination is shortened.

[Brief explanation of the drawing]

FIG. 1 is a main part configuration diagram of the first embodiment, and FIGS. 2, 3, and 4 are the main parts of the second embodiment. Perspective views of main parts of the third and fourth embodiments, fifth
The figure is a perspective view of essential parts of a conventional device. 1...sample, 2,16.25...sample stand, 3...
Measurement aperture, 4... Normal line, 5.28... Light source device, 6
．． 6a, 6b, 6c, 26-... Light receiver, 7... Fixing jig, 7a... Mounting hole, 8... A/D converter, 9...
...Amplifier, 10...Arithmetic processing unit, 11...Case, 12...Rotating sample stage, 13...Rotating axis, 4...
・Rotating shaft stopper, 15.27... Dark box, 6a... Fixed part, 16b... Rotating part, 7... Magnetic rubber 18... Angle scale, 9a... Small annular disc, 19b・
・・Large ring disk, 0... Rotating ring disk, 21... Light source device mounting jig, 2... Light receiver mounting jig, 23... Light receiver mounting port, 4... Cutting Notch.

Claims (4)

[Claims] (1) In a colorimeter that measures the three intensity values X, Y, and Z from reflected light from a sample, the colorimeter is located inside a box with an opening for incident (irradiating) the sample surface, and comes into contact with this opening. On one plane perpendicular to the sample surface, a light source device that can arbitrarily set the incident angle to the sample surface and multiple light receivers that can arbitrarily set the reflected light from the sample surface at different reception angles are arranged. Furthermore, the structure is equipped with an arithmetic processing unit that processes the output signals from these individual photoreceivers, and the incident angle and acceptance angle in the direction perpendicular to the sample surface can be arbitrarily selected. A colorimeter that measures colorimetric values simultaneously and determines color differences between different light reception angle conditions. (2) A rotating sample stage that rotates around the intersection of a plane perpendicular to the sample surface and the sample surface when the sample is placed in contact with the aperture for measuring the sample surface, and the aperture and the rotating sample stage. The measurement method according to claim (1), characterized in that a dark box is provided to cover the whole and block external light, and the direction of the sample surface held on the rotating sample stage can be arbitrarily set with respect to the incident angle and the light reception angle. Color meter. (3) A sample stand that rotates around the center of the aperture is placed in close contact with the aperture for measuring the sample surface, and the contact surface with the sample is made of a magnetic material, and the sample stand is brought into close contact with the sample surface. 2. The colorimeter according to claim 1, wherein the colorimeter (or sample) can be rotated to any desired position. (4) In a colorimeter that measures the three intensity values X, Y, and Z from reflected light from a sample, the colorimeter is located inside a box with an opening for incident (irradiating) the sample surface, and comes into contact with this opening. On one plane perpendicular to the sample surface, a light source device that can arbitrarily set the incident angle to the sample surface and multiple light receivers that can arbitrarily set the reflected light from the sample surface at different reception angles are arranged. It is further provided with an arithmetic processing unit for processing output signals from each of these light receivers, and is located within the box body and close to the opening, and has a large and small annular shape that rotates around the center of the opening. The rotating disks are arranged in mutually rotatable sliding contact, the mounting jig for the light source device is fixed to the small rotating disk, the mounting jigs for the plurality of light receivers are fixed to the large rotating disk, and the sample is The incident angle and acceptance angle in the vertical and horizontal directions relative to the surface can be selected arbitrarily, and the colorimetric values under various incident and acceptance angle conditions can be measured simultaneously, and the sample surface can be viewed three-dimensionally without moving the sample. A colorimeter characterized by measuring color and simultaneously determining color difference between various light receiving angle conditions.