JPH0682310A - Standard correction device of chromaticity monitor - Google Patents

Abstract

PURPOSE:To use a solid optical element for correction of standard chromaticity and precisely perform the correction of the standard chromaticity at the time when the chromaticity of water in a water quality inspection item is measured. CONSTITUTION:An optical element 5 composed of a material having a spectral diffraction transmission characteristic approximated to a rate of spectral diffraction transmission of liquid to be measured such as glass and synthetic resin is provided so as to be freely retreatably inserted between a light casting part 2 and a light receiving part 3. At the time of correction, the optical element 5 is inserted between the light casting part 2 and the light receiving part 3, correction data are obtained, at the time of measurement, it is shifted to a retreating position, a space therebetween is filled with the liquid to be measured and chromaticity of the liquid to be measured is determined. A measurement result is corrected with previously obtained correction data and output as measurement values.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for calibrating reference chromaticity of a chromaticity monitor for monitoring chromaticity of tap water and the like.

[0002]

2. Description of the Related Art The chromaticity of water is one of the water quality inspection items for tap water. In order to constantly monitor this, it has been proposed to install a chromaticity monitor in the middle of the tap water pipe.

In this type of chromaticity monitor, the detection section is composed of a light projecting section and a light receiving section, and the liquid to be measured is filled between them, and the three stimuli of light transmitted through the liquid to be measured detected by the light receiving section. The chromaticity is calculated from the value.

[0004]

By the way, since the chromaticity monitor has a temperature drift characteristic in which the reference value of chromaticity varies with temperature, it is necessary to calibrate the reference chromaticity every time the chromaticity is measured. .

Distilled water is used as the liquid having a standard chromaticity, and air is also used in place of this. When using distilled water, when measuring, first calibrate the reference chromaticity, and then calibrate the reference chromaticity by draining the liquid between the light emitting section and the light receiving section of the detection section and filling it with distilled water. Next, it is first filled with distilled water and then filled with the liquid to be measured, and the measurement of the chromaticity is started. Therefore, in order to constantly monitor the chromaticity online, it is necessary to frequently repeat the complicated operation described above, and it is troublesome to maintain and manage such as constantly supplying distilled water.

When the reference chromaticity is calibrated by using air instead of distilled water, it is only necessary to remove and refill the liquid to be measured filled in the detecting portion, so that the operability is improved, but the operability is improved. There is a problem that the difference in the refractive index between the measurement liquid and the air causes a large difference in the amount of light received by the light receiving unit, which lowers the measurement accuracy.

The present invention is intended to solve the above problems.

[0008]

In order to solve the above-mentioned problems, the present invention replaces filling the distilled water between the light-projecting section and the light-receiving section of the detecting section with a predetermined value when calibrating the reference chromaticity. An optical element having a spectral transmission characteristic is arranged, and the liquid to be measured is accommodated in a chromaticity monitor that determines the chromaticity of the liquid to be measured from the spectral characteristics of light transmitted through the liquid to be measured. A light projecting section arranged on the wall surface of the container, a light receiving section arranged on the wall surface of the container at a position for receiving light projected from the light projecting section, and inserted between the light projecting section and the light receiving section. An optical element having a predetermined spectral transmission characteristic that guides the light projected from the light projecting section to the light receiving section, and the optical element is set at the insertion position between the light projecting section and the light receiving section during chromaticity calibration. A light that sets the optical element to the retracted position outside the insertion position when measuring the chromaticity of the measurement liquid. Characterized by comprising an element moving unit.

The optical element can be made of a material such as glass or synthetic resin, and is preferably made of a material having a spectral transmission characteristic close to that of the liquid to be measured.

[0010]

The optical element movably arranged between the light projecting section and the light receiving section is inserted between the light projecting section and the light receiving section at the time of calibration, and other than between the light projecting section and the light receiving section at the time of measurement. The liquid to be measured is filled between the light projecting section and the light receiving section. Since the solid-state optical element is used for the calibration of the reference chromaticity, the frequent calibration operation becomes easy.

[0011]

Embodiments of the present invention will be described below.

FIG. 1 shows a chromaticity monitor embodying the present invention.
FIG. 10 is a perspective view showing the outline of the configuration of FIG.
Reference numeral 0 is a detection unit, 200 is a photoelectric conversion unit, and 300 is a data processing unit.

The detection unit 100 includes a container 1 containing the liquid S to be measured, a light projecting unit 2 and a light receiving unit 3 provided on the side wall of the container 1, and a glass inserted between the light projecting unit 2 and the light receiving unit 3. , An optical element 5 made of a transparent material such as a synthetic resin and having a predetermined spectral transmission characteristic.

The optical element 5 is movable in the direction of the arrow a through a plunger 9 and a frame 8 which reciprocate by a drive mechanism (not shown), and when the reference chromaticity is calibrated, the optical element 5 and It is set at the insertion position between the light receiving unit 3 and the chromaticity measurement of the liquid S to be measured, and between the light projecting unit 2 and the light receiving unit 3,
It is configured to be set to a retracted position outside the insertion position.

Further, the light projecting section 2 includes a photoelectric conversion section 2 which will be described later.
The light projected from the light source L provided in 00 is guided through the optical fiber 6 and projected toward the light receiving unit 3.
The light received by the light receiving section 3 is guided through the optical fiber 7 to a photo diode described later provided in the photoelectric conversion section 200 described later. Further, the container 1 is configured so that a liquid to be measured (not shown) for measuring the chromaticity, here tap water, is constantly supplied to and filled in the container 1 by a liquid to be measured supply (not shown).

FIG. 2 is a circuit block diagram of the chromaticity monitor, which comprises a photoelectric conversion unit 200 and a data processing unit 300.

The photoelectric conversion unit 200 measures the chromaticity of the liquid S to be measured and outputs a measurement data of a sample, and a light source measurement unit which measures a light source L and outputs reference data. Consists of. This is to obtain a stable measurement result by canceling the measurement error due to the fluctuation of the light source L and the like by obtaining the ratio of the measurement value of the measured liquid S and the measurement value of the light source L. The sample measuring unit and the light source measuring unit each have three series of circuits, because this is to decompose the measured light into three basic components for processing.

The sample measuring unit is a photo diode P1 to P.
3, filters F1 to F3 for separating the detection light arranged in front of the photo diode into basic color components, and a photoelectric conversion circuit E
1-E3, gates G1-G3, sample-hold circuit H
1 to H3 and gates G7 to G9. The light source measuring section includes photo diodes P4 to P6, filters F4 to F6 for separating the detection light arranged in front of the photo diodes into basic color components, photoelectric conversion circuits E4 to E6, and gates G4 to G6. It is composed of sample hold circuits H4 to H6 and gates G10 to G12.

The data processing unit 300 is a central processing unit (CP).
U) 22, a ROM 23 connected to the CPU 22 for storing a control program, a color conversion program, etc., a RAM 24 for temporarily storing color information, etc. for which arithmetic processing has been performed, a control clock signal generator 25, an input of the CPU 22 and peripheral devices. I / O control unit 27 for controlling output, display unit 28 for displaying and printing measurement results connected to I / O control unit 27, warning unit 2
9, the keyboard 30, the gates G1 to G6, the optical element 5 of the detector 100 in response to the calibration / measurement switching signal, and the retracted position between the light emitter 2 and the light receiver 3 and the withdrawal. An optical element drive circuit 3 for driving a drive mechanism (not shown) that moves to a position
1 and an illumination circuit 32 that controls the lighting of the light source L.

Next, the operation will be described with reference to the flow charts shown in FIGS.

First, the container 1 of the detection unit 100 is filled with the liquid to be measured, and a series of processes such as power-on, program loading, and initialization are executed to set the apparatus to an operable state. The chromaticity reference calibration process and the chromaticity measurement process of the liquid to be measured are performed in this order.

First, the chromaticity-based calibration process will be described. The flow chart in FIG. 3 shows the calibration processing based on chromaticity, and the tristimulus values X0, Y0, which are the standard values of the chromaticity of the optical element 5 used as the reference for calibration from the keyboard 30, are shown. Input Z0 (step P1). The optical element 5 is set at the insertion position between the light projecting section 2 and the light receiving section 3 (step P2), the light transmitted through the optical element 5 is detected, and the detection signal is used as a tristimulus value calculation rule described later. The tristimulus values Xm, Ym, and Zm indicating the chromaticity of the optical element 5 are calculated by chin (step P3).

Next, the calibration constants α0 and β0 are calculated by the following equation.
, Γ0 is calculated (step P4), and α0 = X0 / Xm β0 = Y0 / Ym γ0 = Z0 / Zm The calibration constants α0, β0, γ0 obtained by the calculation are stored in the RAM 24.
(Step P5).

Next, the process of measuring the chromaticity of the liquid to be measured will be described. The flow chart of FIG. 4 shows the measurement process of the chromaticity of the liquid to be measured, and the optical element 5 at the insertion position between the light projecting section 2 and the light receiving section 3 is moved to the retracted position and set. The liquid S to be measured is filled between the light emitter 2 and the light receiver 3 (step P
11), the light transmitted through the liquid to be measured S is detected, and the detection signal is calculated by a tristimulus value calculation routine described later, and the tristimulus values Xs, Ys, and Zs indicating the chromaticity of the liquid S to be measured are detected. Is calculated (step P12).

Calibration constant α0 stored in RAM 24
, Β0, γ0 are read (step P13), and the tristimulus values Xs, Ys, Zs indicating the measured chromaticity of the measured liquid S are multiplied by the calibration constants α0, β0, γ0 for correction (step P14). The color space conversion of the tristimulus values X, Y, and Z indicating the corrected chromaticity of the measured liquid S into the designated color system by known means (step P15) is displayed on the display unit 28, After printing (step P16), the process ends.

Next, the flow chart step P3 shown in FIG. 3 and the flow chart step P1 shown in FIG.
The tristimulus value calculation routine shown as 2 will be described with reference to the flow charts shown in FIGS.

First, the reset signal for resetting the sample hold circuits H1 to H6 is turned on, and the reset signal is turned off after waiting a predetermined time (step P21).
~ Step P23). As a result, the sample hold circuits H1 to H6 are in the reset state. The gates G1 to G6 are turned on and the illumination circuit 32 is turned on to turn on the light source L (step P24). The light transmitted through the optical element 5 during calibration and the light transmitted through the measured liquid S during measurement are filtered by the filter F1.
Through F3 to be separated into basic color components, detected by photo diodes P1 to P3, amplified by photoelectric conversion circuits E1 to E3, and passed through gates G1 to G3 to sample hold circuits H1 to H3. Holded. Further, in order to obtain the fluctuation correction signal of the light source L, the light projected from the light source L directly passes through the filters F4 to F6 and is decomposed into the basic color components, which are detected by the photo diodes P4 to P6 and are detected by the photoelectric conversion circuit E.
It is amplified by 4 to E6 and is held in the sample hold circuits H4 to H6 through the gates G4 to G6.

After waiting a predetermined time required to complete the above processing (step P25), the gates G1 to G6 are turned off.
F, and the illumination circuit 32 is turned off (step P2
6). The coefficient i designating the gate number is set to 7 (step P27), and the counter provided in the CPU is reset (step P28). Gate Gi (First is Gate G
7) is turned on, and the data held in the sample hold circuit Hi is output to the A / D converter 21 (step P29).

Whether or not the output of the A / D converter 21 is "H" is determined. If it is not "H", the content of the counter is incremented by 1 (steps P30 and P31). A / D converter 21
When the output of is "H", the output data Ci of the A / D converter 21 is stored in the register of the CPU (step P3).
2). The gate Gi is turned off (step P33) and whether the coefficient i exceeds 12 or not, that is, the gates G7 to G12
Are sequentially opened to determine whether or not the processing has been completed for all the data held in the sample hold circuits H1 to H6. If i≤12, the process returns to step P29, where i>
In the case of 12, the process proceeds to the next process (step P34).

Reset of the sample hold circuits H1 to H6, ON / OFF of the proof circuit 32, and gates G1 to G6.
FIG. 7 shows ON / OFF of the gates G7 to G12 and the operation timing of the A / D converter 21.

The processing of steps P35 to P48 is performed by the light source L
With the light not lit, the light transmitted through the optical element 5 during calibration and the light transmitted through the measured liquid S during measurement are measured, and the output data is stored in the register of the CPU. Since the processing is the same as the processing in steps P21 to P34 described above, detailed description will be omitted. Incidentally, here, the output data of the output data A / D converter 21 is identified as Di.

Through the above processing, data C1 to C6 measured with the light source L turned on and data D1 to D6 measured without the light source L turned on are stored in the register of the CPU. It will be.

At step P49, the intermediate values A (1) to A (6) are calculated by performing the following arithmetic expressions.

A (1) = C (1) −D (1) (1) A (2) = C (2) −D (2) (2)・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ A (6) = C (6) -D (6) ・ ・ ・ ・ ・ (6) Next, step P50 Then, the following calculation for correcting the fluctuation of the light source L is executed, and the tristimulus values Xm, Ym, Z of the optical element 5 are
m, or the tristimulus values Xs, Ys, and Zs of the measured liquid S are obtained, and the process ends.

Xm (Xs) = A (1) / A (4) ... (7) Ym (Ys) = A (2) / A (5) ... (8) Zm (Zs) = A ( 3) / A (6) ... (9) FIG. 8 is a diagram showing the outline of the configuration of a remote monitoring system for a chromaticity monitor embodying the present invention, in which 100
Is a detection unit, 200 is a photoelectric conversion unit, 300 is a data processing unit, 400 is a measurement control unit, 500 is an optical element drive operation unit, 600 is a telephone with a built-in modem, 700 is a general public line (telephone line), and 800 is The control monitoring board is shown.

The measurement control section 400 issues an instruction to start measurement to the optical element drive operation section 500 and the data processing section 300 at regular time intervals. The data processing unit 300 measures the tristimulus values and the like of the liquid to be measured according to the determined order as described above,
The calculation is performed according to various color modes and the result is stored. The colorimetric mode is converted into a chromaticity correlation number by the measurement control unit 400 by an arithmetic expression for comparison with the chromaticity frequency of the analytical method using the previously obtained standard solution.

The converted chromaticity correlation number is data-processed, and then transmitted from the telephone 600 with a built-in modem to the control and monitoring board 800 via the general public line 700 and the like, and is converted into the normal chromaticity and recorded and displayed. .

FIG. 9 shows the structure of the detecting section 100 shown in FIG. A pipe 101 for introducing the liquid to be measured is connected to one end of the container 1, and a stop valve 103, a pressure reducing valve 104, a check valve 10 are provided between the liquid to be measured introducing port 102 and the container 1.
5 are provided. On the other hand, a pipe 106 is provided at the other end of the container 1.
The measured liquid to be measured is discharged from the discharge port 109 through the pipe 106. An electromagnetic valve 107 and a stop valve 108 are provided between the container 1 and the discharge port 109.

An optical element 5 is inserted inside the container 1, and is connected to a driving device 150 outside the container 1 via a plunger 9. A dog 153 is provided on the plunger 9 protruding outside the container 1, and the insertion position switch 151 and the retreat position switch 152, which are installed in the axial direction of the plunger 9, are mechanically kicked to the terminal board 501. Send an electrical signal. A float switch 154 is provided on the upper part of the container 1 to detect whether or not the container 1 is sufficiently filled with the liquid to be measured.

Next, the operation will be described with reference to the flow charts of FIGS.
The chart will be described with reference to the timing chart of FIG.

First, the initial condition setting operation will be described with reference to the flowchart of FIG. Turn on the float switch 154
(Step P101), the solenoid valve 107 is closed (step P101).
102), the insertion position switch 151 is turned off (step P103), the retracted position switch 152 is turned on (step P104), and the counter 502 is set to 0 (zero) (step P105).

Next, the measuring operation will be described with reference to the flow chart of FIG. The electromagnetic valve 107 is opened, the solution to be measured is introduced into the container 1, and the solution to be measured in the container 1 is exchanged by flowing it for a certain period of time (steps P111 and P112). Next, the electromagnetic valve 107 is closed (step P113), the optical element 5 is reciprocated between the insertion position and the retracted position (the number of times is counted by the counter 502), and the liquid to be measured is stirred (steps P114 to P119). ). After reciprocating four times, the optical element 5 is stopped at the insertion position, and the calibration value is measured by the optical element 5 (steps P120 to P121). The optical element 5 is returned to the retracted position and the liquid to be measured is measured (steps P122 to P122).
P124). The measured value is sent to the data processing unit 300 and processed. When the above process is completed, the solenoid valve 107 is closed, the insertion position switch 151 is turned off, the retracted position switch 152 is turned on, the counter 502 is 0, and one measurement is completed.

[0043]

As described above, according to the present invention, the optical element is movably arranged at the insertion position between the light projecting portion and the light receiving portion and the retracted position away from the light receiving portion. It is set at the insertion position between the light projecting section and the light receiving section to eliminate the liquid to be measured between them, and the calibration is performed by an optical element having a predetermined spectral transmission characteristic as a chromaticity calibration standard. When measuring the chromaticity of the liquid to be measured, if the optical element is set to the retracted position, the liquid to be measured is filled between the light projecting portion and the light receiving portion, so that the measurement can be performed immediately. Unlike conventional devices, it is not necessary to replace the calibration reference solution such as distilled water with the measured solution each time calibration is performed, so frequent calibration work can be performed very easily. There is no need to constantly replenish the reference solution, and maintenance management becomes easy.

[Brief description of drawings]

FIG. 1 is a perspective view showing an appearance of a chromaticity monitor embodying the present invention.

FIG. 2 is a circuit block diagram of a chromaticity monitor.

FIG. 3 is a flowchart of a calibration process.

FIG. 4 is a flow chart of measurement processing.

FIG. 5 is a flowchart (part 1) of arithmetic processing.

FIG. 6 is a flowchart of the arithmetic processing (part 2).

FIG. 7 is a timing chart showing the timing of control operation.
To.

FIG. 8 is a diagram showing a schematic configuration of a remote monitoring system for a chromaticity monitor.

FIG. 9 is a diagram showing a schematic configuration of a detection unit.

FIG. 10 is a flowchart for explaining the setting operation of initial conditions at the time of measurement.

FIG. 11 is a flowchart for explaining the measurement operation.

FIG. 12 is a timing chart of initial condition setting and measurement operation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container 2 Light projecting part 3 Light receiving part 5 Optical element 6, 7 Optical fiber 9 Plunger L Light source 100 Detection part 200 Photoelectric conversion part 300 Data processing part

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Mitsunobu Ota 2-3-13 Azuchi-cho, Chuo-ku, Osaka, Osaka International Building Minolta Camera Co., Ltd. (72) Inventor Nagahiro Shoji 1-12 Kitahorie, Nishi-ku, Osaka No. 19 Stock Company Kurimoto Iron Works

Claims (4)

[Claims] 1. A chromaticity monitor for determining the chromaticity of a liquid to be measured from spectral characteristics of light transmitted through the liquid to be measured,
A light projecting section arranged on the wall surface of the container for containing the liquid to be measured, a light receiving section arranged on the wall surface of the container at a position for receiving the light projected from the light projecting section, the light projecting section and the light receiving section. An optical element having a predetermined spectral transmission characteristic that guides the light projected from the light projecting section to the light receiving section, and the optical element is inserted between the light projecting section and the light receiving section during chromaticity calibration. A reference calibration device for a chromaticity monitor, comprising: an optical element moving means for setting the optical element to a retracted position outside the insertion position when measuring the chromaticity of the liquid to be measured. 2. The standard calibration device for a chromaticity monitor according to claim 1, wherein the optical element is made of a glass material. 3. The standard calibration device for a chromaticity monitor according to claim 1, wherein the optical element is made of a synthetic resin material. 4. The standard calibration device for a chromaticity monitor according to claim 1, wherein the optical element is made of a material having a spectral transmission characteristic close to the spectral transmission rate of the liquid to be measured. Degree monitor-reference calibration device.