JPS5926023A - Automatic colorimeter for light quantity - Google Patents

Abstract

PURPOSE:To measure the X, Y, and Z value of a sample stably by equalizing mechanisms which equalize two optical paths on a standard and a sample side in the quantity of light, distributing light energy uniformly in incident luminous flux, and performing zero resetting, standard matching, and measurement in one cycle. CONSTITUTION:Light from a light source 1 passes through a lens and a rotating disk 8 and is distributed through a prism 4 to the sample-side optical path 23 to the sample 10 and the standard-side optical path 24 to a standard plate 11. The light of either optical path passes through an aperture of the rotating disk 8, and reflected light beams from the sample 10 and standard plate 11 are photodetected by the X, Y, and Z photodetectors 13, 14, and 15 of an integrating sphere 12 individually. The quantities of light of those two optical paths are equalized to each other through photodetectors 17 and 19 on the optical paths by the upward/downward movement of a light-quantity adjusting diaphragm 21. The standard plate, sample 10, and a reference standard plate 11 are set and irradiated with light whose quantity is adjusted to find the X, Y, and Z absolute values of the measured sample. Pieces of luminous flux 23 and 24 are passed through three apertures at equal intervals of the rotating disk 8 by turns to perform the zero resetting, standard matching, and measurement in a 120 deg. rotation of the disk 8.

Description

[Detailed description of the invention] The present invention relates to a two-light path type colorimeter.

One of the typical conventional colorimeters using a two-light path method is a Birdy type spectrometer. FIG. 1 is an explanatory diagram of the optical path. The light from the light source 15 passes through the first slit 1, the first prism 2, the reflecting mirror 3, the second slit 4, the second prism 5, and the third slit 6. , Wollaston Prism 8. The beam is split into two optical paths by the 20th optical prism 9, and the ratio with the light emitted by the Noritzker motor 10 is determined to determine the spectral reflectance or spectral transmittance of the sample. The disadvantage of this spectrometer is the 10th-/
Due to dirt on the Hyakun prism, Wollaston prism, and No. 20 Shion prism, the amount of light on the standard side and the light amount on the sample side may change, making standard alignment impossible. This causes errors in measured values.

Another example of the conventional method using the two-light path method is the paternal photometry method. FIG. 2 is an explanatory diagram of the optical path. The light from the light source 1 is converted into parallel light by the lens thread 2, and the RGB filter disk 3 is turned into parallel light by the drive motor 4.
(The light becomes r'e light and is further divided by the semicircular mirror 7 into a standard side optical path 18 and a sample side optical path 19 every 180° rotation.

The light transmitted through the standard side cell 16 enters the light receiver 14 via the mirror 13. Further, the sample-transmitted light that has passed through the sample-side cell 17 enters the light receiver 14 via the mirror 12. Light receiver 14
receives the transmitted light from the standard side cell and the sample side cell every 180 degrees due to the rotation of the semicircular mirror rotating disk T, so from this ratio, the transmittance of the sample when it passes through the RGB filter can be determined. This measurement method has the disadvantage that abnormal light rays are generated due to optical deterioration of the semicircular mirror 7, resulting in errors in the measured values.

In both of the conventional methods mentioned above, zero adjustment is performed manually by inserting a lens into the optical path on the sample side, but this is troublesome as it is necessary to repeat this operation frequently if the measurement lasts a long time. In both conventional methods, standard plates with the same reflectance or transmittance are set on the standard side and the sample side to perform standard matching, and are manually inserted, but two identical plates are prepared. This is difficult in practice, has the disadvantage that the measurement results show a difference between the two, and is troublesome because it requires frequent operations when the measurement takes a long time. Further, there is a drawback t4 that the amount of light in each optical path is not equal.

The present inventor has completed the present invention as a result of thorough investigation to eliminate the drawbacks of the conventional method explained above.In other words, the present invention is based on the principle of colorimetry using a two-light path method. It also has an automatic light intensity adjustment function that constantly measures and equalizes the incident light intensity on the sample side, and is equipped with a lens system consisting of a cylindrical lens so that the light energy of the light source bulb is evenly distributed within the incident light flux, and zero adjustment is performed. This is an automatic photochromic colorimeter that is equipped with a rotating disk horizontal groove that performs standard alignment and measurement operations in one cycle, and is capable of measuring the XYZ values of a sample.

Next, embodiments of the present invention will be described with reference to the drawings.

In FIG. 3, light from a light source 1 becomes a parallel beam of light through a lens 2 and a cylindrical lens 3, and a rotating disk 8,
It passes through the prism 4 and hits the sample 10. Another light from the light source is turned into a parallel light beam by a lens 5 and a cylindrical lens 6, passes through a prism 7 and a rotating disk 8, and hits a standard plate 11. Since only the light of one of the optical paths passes through the aperture of the rotating disk 80, the reflected light of the measurement sample and the standard plate are emitted alternately, and the integrating sphere 1
The light is separately received by XYz light receivers 13, 14, and 15 provided at 2. In addition, the number of openings in the rotating disk 8 driven by the motor 9 is three in FIG. 3, but one
,2. Other numbers are also possible.

The automatic light amount adjustment function uses the sample side optical path 23 and the standard side optical path 24.
No-f mirrors 16, 18, set in each optical path. Using the sample-side light scatter measurement receiver 17 and the standard-side light scatter measurement receiver 19, the light amount adjustment diaphragm 21 is moved upward by the light amount comparison intensifier 20 and the aperture drive motor 22, and the standard side light beam and the sample side light beam are measured. It is made equal to light orange. If this adjustment operation switch is turned on, the light years of each path on the sample side and marker side will automatically become equal when the colorimeter is in operation.

When measuring with this colorimeter, first set a standard plate whose absolute value is known in place of the measurement sample 10, set the reference standard plate in the position of the standard plate 11, and use the adjustment function to adjust the amount to the same amount. The adjusted amount of light is applied to both, and the XYZ values of the reference standard plate are determined from the ratio of the reflected light. Next, the measurement sample 10 is set, and the XY
The absolute value of Z can be found. Here, the reference standard plate is a standard plate that has characteristic values that are reliable over a long period of time and can be recognized as a standard, and is used for regular measurements.

In this embodiment, the lens thread made up of a cylindrical lens is combined with a convex lens. The light source of a light bulb is an elongated filament, but in the conventional technology, a normal lens system is used to create a parallel light beam, so that the light energy distribution within the light beam is not uniform. In the present invention, the one-dimensional refractive properties of the cylindrical lens are used to correct the elongated shape of the image of the light source into a short and wide shape and expand the area. The light energy distribution is strong and uniform. Figure 4 shows this relationship.

It is something. <aD of the changing light.

In addition, the structure is such that zero adjustment, reference standard confirmation, and sample measurement can be performed in one cycle by turning on a switch, and its basic structure is based on a rotating disk mechanism. FIG. 5 shows the relationship between the rotating disk and the luminous flux. There are three openings A, B, and C in the rotating disk, and the positions are equidistant from each other on the same circumference. In the figure shown in (1), the tilting of the standard side beam and sample side beam is also blocked by the rotating disk, so in this relationship,
4. In other words, zero point reading is performed. Since the reference standard side light flux passes through the A hole at t at ω), the XYz of the reference standard plate
Measure the value. In (3), since the ei sample side light beam passes through the B hole, x y Z lii of the sample is measured.

(1), (2), and (3) are relationships that hold while the rotating disk rotates approximately 90 degrees, and the rotating disk rotates approximately 120 degrees per cycle t of zero adjustment, reference standard confirmation, and sample measurement. It will end while it rotates.

The structure and operation of the present invention have been explained above, and next, the effects thereof will be explained. 6111 Since the nodal action that always makes the light areas of the two optical paths equal at a fixed time works automatically, stable measurements can be made at all times.

Since it uses the reflection of the sun instead of mirror reflection, there is no occurrence of abnormal rays due to mirror deterioration, long-term measurements can be made, and maintenance is easy.

Zero adjustment is performed automatically for each measurement, making it easy to operate.
The standard adjustment involves constantly adjusting the light intensity and determining the 6111 constant value in relation to the reference standard, so once it is done, long-term measurements can be made.8 By using a cylindrical lens, the C light source light bulb t
This means that a large amount of light can be used with a small lamp.

Zero adjustment, reference standard confirmation, and measurement are performed automatically for each measurement, and the measured value is obtained in relation to the reference standard, resulting in good reproducibility.

Since the optical path is determined by the light source, lens thread, prism, and integrating sphere, there are no extraneous rays, and since the optical path is intermittently interrupted by the rotating disk, the same amount of light is always provided.

[Brief explanation of drawings]

Figure 1 is a Birdy type spectrometer, Figure 2 is the optical system for general cross-reflection photometry, Figure 3 is an explanatory diagram of the colorimeter according to the present invention, and Figure 4 is a filament using a rhinodorical lens. Image formation 'c/je L, FIG. 5 is an explanatory diagram of the relationship between the rotating disk and the light beam. Next is the number shown in Figure 3. 1... Light source bulb, 2, 5... Lens, 3.6.
... Cylindrical lens, 4, 7... Prism, 8
... Rotating disk, 9... Motor, 10... Measurement sample, 11-... Reference standard plate, 12... Integrating sphere, 13.
...Receiver for Y, 14...Receiver for X, 15...Z
Receiver for 16.18...half mirror 111...
Sample side Koryu 6111 constant receiver, 19・i, f4 semi-111
11)'(, ltt No. 61 constant light receiver, 20... light intensity comparison intensifier, 21... main branch adjustment diaphragm, 22.
...Aperture drive motor, 23...Sample side optical path, 24...
・Standard side optical path. 71Figure 1-4

Claims (1)

[Claims] In the color measurement method in which two optical paths enter the integrating sphere through two optical paths, one on the standard side and one on the sample side, an automatic light intensity adjustment function that constantly measures and equalizes the amount of incident light in the two optical paths, and an even distribution of the light energy of the light source bulb within the incident luminous flux. An automatic light intensity colorimeter characterized by having a lens system configured with a cylindrical lens so as to do the same, and a rotary disk mechanism that performs zero adjustment, standard adjustment, and measurement operations in one cycle.