JPS58103645A - Measuring apparatus of turbidity - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a turbidity measuring device for measuring turbidity in a solution, which is capable of waterproofing electric circuit parts such as a light source, a light receiving element, and an arithmetic circuit, and is capable of preventing turbidity in a deep place. Attenuation of light also occurs when measuring
The present invention provides a turbidity measuring device that does not cause problems such as noise.

An embodiment of the present invention will be described below with reference to the drawings. In FIGS. 1 and 2, 1 is the main body of the optical system,
This four-book body 1 has a shape in which a light-emitting side casing 2 and a light-receiving side casing 3 are connected by a connecting piece 4. 6 is the light emitting side housing 2
A refractive index gradient lens 6 is disposed inside the protective glass 6. Reference numeral 7 denotes an optical fiber whose one end is introduced into the casing 2 on the light emitting side. 8 is a protective glass provided in the opening 1 of the housing 3 on the light receiving side, and lenses 9#10j11 are provided corresponding to each inner surface of this protective glass 8. 12,
Reference numerals 13 and 14 each indicate an optical fiber whose one end is introduced into the housing 3 on the light receiving side, and each of the optical fibers 12 to 14 guides the light collected by the lenses 9 to 11 to the outside of the housing 3. It is something to do. 16 is a covering tube for reinforcing the optical fiber 7, and 16 is a covering tube for reinforcing the optical fibers 12-14. Said coated tube 15.
16 is further articulated with another covering tube 17. Reference numeral 18 denotes an electric circuit section, and a light source 191 and light receiving elements 20 and 21 are arranged in the electric circuit section 18 .

The main body 1 of the optical system of the turbidity measuring device is inserted into the measurement solution, the electric circuit section 18 is placed on the ground, and the light from the light source 19 is transmitted through the optical fiber 7 into a refractive index gradient type. It reaches lens 6. The parallel light from this lens 6 is irradiated into the measurement solution through the protective glass 6. A part of the parallel light beam traveling through the measurement solution is scattered by particles in the measurement solution.

The scattered light scattered by the dots in the solution enters the lens 10s11 via the protective glass 8 of the housing 3 on the light receiving side. on the other hand,
Transmitted light that does not cause scattering in the measurement solution travels straight,
The light enters the lens 9. The light focused by the lens 1ol 11 is transmitted to the light receiving element 2 via the optical fibers 13 and 14, respectively.
Reach 1. On the other hand, the light focused by the lens 9 reaches the other light receiving element 2o via the optical fiber 12.

In this embodiment, the transmitted light and scattered light due to the turbidity of the solution are detected, and the turbidity in the solution is detected by dividing the two (scattered light output/transmitted light output).

FIG. 3 is a block diagram of a circuit that calculates turbidity from the output S1 of the transmitted light receiving element 2o and the output S2 of the scattered light receiving element 21, 22 is an amplifier, and 23 is a division calculation circuit.

FIG. 4(A) shows changes in the output of transmitted light and scattered light with respect to changes in turbidity, and the output of scattered light decreases when the turbidity is exceeded. - However, dividing the transmitted light/scattered light output (82
÷8+=83), a relationship between turbidity and calculation output of a curve without an inflection point as shown in FIG. 4(B) can be obtained.

Further, by dividing both output signals in this manner, the influence of dirt on the protective glasses 5 and 8 can be canceled out. That is, if the light attenuation rate due to the glass 6.8 is a, the above division calculation formula becomes: If the dirt on the glass 6.8 is uniform, the influence of the dirt is canceled out.

The present invention has the above configuration, and according to the present invention, the optical system part and the electrical system part are separated and the optical system is solidified, so light can be transmitted through optical fibers without problems of heat generation and water intrusion. Therefore, it is possible to provide a turbidity measuring device that does not generate electrical noise and has highly sensitive performance.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the main parts of a turbidity measuring device according to an embodiment of the present invention, FIG. 2 is a sectional view of the main parts of the device, and FIG. 3 is a block diagram of the electric circuit section of the device. Figure 4 (Mu) and Italy) are characteristic diagrams of the same device. 1... Main body, 2, 3... Housing, 4...
...Binding piece, 6...Protection glass, 6...
...gradient index lens, 7...optical fiber, 8...protective glass, 9,10°11...
...Lens, 12, 13.14...Optical fiber, 15, 16, 17...-Coated chain, 1B.
...Electric circuit section, 19...Light source, 20,
21... Light receiving element. Name of agent: Patent attorney Toshio Nakao and 1 other person11
a1 183 Zukyu 9 4th cause

Claims (1)

[Claims] A second light beam that guides the light from the light source to a gradient index lens, and guides the transmitted light that has come out of the gradient index lens and passed through the measurement solution to a first light receiving means. A turbidity measuring device comprising a fiber and a third optical fiber that guides the scattered light emitted from the gradient index lens and scattered in the measurement solution to a second light receiving means.