UA147071U - FIBER-OPTICAL TURBIDIMETER - Google Patents

Abstract

The fiber-optic turbidimeter consists of a radiation source, photodetectors, a processor module with a liquid crystal screen, combined in a reflectometer, a splitter, a primary fiber and a base, according to the utility model, the base contains a fiber-optic sensing element, which is a central light a mirror layer of sapphire glass at the end, which is connected to a set of welded rings made of crown and heavy flint, which are coaxial with the central fiber, connected to the primary fiber connected to a bimetallic plate, multiplexer / demultiplexer a splitter, a block of optical spectral filters, a radiation source and photodetectors connected to a processor module with a liquid crystal screen, combined as part of a reflectometer.

Description

A useful model belongs to fiber-optic turbidimeters, which are based on the control of the optical properties of light guides. Field of application - operational control of the state of technical environments. For automated information and measurement systems for monitoring technical environments in dangerous operating conditions on ships and submarines (1-31.

An optical turbidimeter is known, which consists of a base that forms a cuvette for the controlled environment, a radiation source, an emitting LED, a light guide that receives radiation, a photoreceptor and a processor module with a liquid crystal screen, combined into a reflectometer (21.

Disadvantages of the device, which are due to the use of an emitting LED, a light guide that receives radiation, located on different sides of the cuvette: - the need to constantly adjust the alignment of the light guides under the influence of operational destabilizing factors; - the need for periodic grinding of the ends of light guides made of quartz glass to remove the layer of glass destructured under the influence of controlled environments; - the absence of the possibility of taking into account the temperature of the controlled environment on the measurement results; - strong dependence of measurement accuracy on the state of pollution of the air mixture; - the need to use the largest possible optical base to obtain a satisfactory level of device sensitivity.

As the closest analogue, a fiber-optic turbidimeter consisting of a base, a radiation source, a splitter, a light guide of the primary information formation channel, a light guide of the reference channel, a cuvette with a controlled environment and a standard, photodetectors, a comparator and a processor module with a liquid crystal screen, combined in of the reflectometer |ZI.

Disadvantages of the device, which are due to the use of the standard, the light guide of the primary information formation channel and the light guide of the reference channel: - the impossibility of achieving full power compensation, which is due to the errors of the standard;

Зо - there is no thermocompensation of temperature fluctuations of the external environment and the controlled environment; - the need to manufacture and install the fiber optic cable of the primary information formation channel and the fiber optic cable of the reference channel with extremely high quality to avoid the creation of conditions for the appearance of parasitic modulation; - the need for a complex mechanical system for positioning the standard relative to the light guide.

The basis of a useful model is the task of creating a fiber-optic turbidimeter, in which there is no mechanical positioning system, increased protection of elements, no dependence on the state of the external and controlled environment, and at the same time the high level of sensitivity and speed of devices of known types are preserved.

The task is solved by the fact that a fiber-optic turbidimeter consisting of a radiation source, photodetectors, a processor module with a liquid crystal screen, combined into a reflectometer, a splitter, a primary light guide and a base, which is characterized by the fact that the base contains a fiber-optic sensitive element, which is a central light guide with a mirror layer of sapphire glass at the end, to which is connected a set of welded rings made of crown and heavy flint, which are coaxial with the central light guide, which is connected to the primary light guide, coupled with a bimetallic plate, a multiplexer/demultiplexer, a splitter, a block of optical spectral filters, a radiation source and photodetectors connected to a processor module with a liquid crystal screen, combined into a reflectometer.

The technical effect is achieved due to the fact that the combination of optical elements ensures: - more adequate transformation of the parameters of the controlled environment into changes in the information signal; - compensation of the influence of destabilizing factors on the measuring channel of the sensor; - the possibility of creating an extensive network of control of technical environments in special conditions; - improvement of the quality of operation due to the use of materials with a close coefficient of thermal propagation and the selection of a rational modulation scheme of reference radiation.

The essence of the useful model is explained by the drawing (Fig. 1), which shows a base made of quartz glass 11, in which a central light guide 7 is fixed with a reflective layer of sapphire glass 10 on the end, coaxially mounted to which is a set of rings 9 made of crown and heavy flint. The range of refractive indices of the rings is closest to the range of refractive indices of the controlled medium. The second end of the central light guide is connected to the primary light guide, which is connected to the multiplexer/demultiplexer 5. In the section between the multiplexer/demultiplexer and the central light guide, the primary light guide is connected to the bimetallic plate 6.

The radiation from the source enters the block of optical spectral filters 3, where it is divided into several rays with different wavelengths. The distributed radiation through the splitter 4, the multiplexer/demultiplexer and the primary light guide enters the central light guide.

A central light guide, rings of crown and heavy flint, and a controlled environment on the outside of the rings form a three-layer optical waveguide. When the controlled medium comes into contact with the rings in the central light guide, the conditions of complete internal reflection of light are violated, which occurs as a response to the tunnel pumping of radiation from the light guide to the outside. The refractive indices of the rings are selected in such a way as to ensure the maximum pumping of optical radiation from the light guide to the outside when in contact with the controlled environment within three regimes: the appearance of pollution in the "trace" concentration; the appearance of "anxiety" in concentration; appearance in concentration "accident".

Violation of the conditions of complete reflection of light in the central light guide is reflected in the change in the intensity of light radiation, which is reflected from the reflective layer of sapphire glass. The radiation is returned through the splitter to the photoreceiver and reflectometer, where the processing of the information signal I4-61|.

List of drawing figures

Fig. 1. Fiber-optic turbidimeter: 1 - processor module with a liquid crystal screen, combined in the reflectometer; 2 - radiation source; C - block of optical spectral filters; 4 - splitter; 5 - multiplexer/demultiplexer; 6 - bimetallic

Z plate; 7 - primary light guide; 8 - central light guide; 9 - crown and heavy flint rings; 10 - reflective layer; 11 - base; 12 - photo receivers.

A combination of crown and heavy flint rings, fiber optic cables, optical spectral filter block, multiplexer/demultiplexer and reflectometer are used to implement a useful model.

In the calibration mode, i.e. in the absence of a controlled environment, radiation is generated in the reflectometer, which comes from the central light guide. In the light guide, which is optically connected to the rings, there is a decrease in the intensity of the optical radiation passing through it, which is due to attenuation in the light guide material under the influence of operational factors. The intensity of the radiation returning to the reflectometer is recorded and stored as a correction.

In the dynamic mode, when the central optical fiber connected to the rings is immersed in a controlled environment, optical radiation is pumped from the optical fiber to the outside, i.e., an optical tunnel effect occurs. After that, the radiation, changed in intensity, is reflected from the reflective layer and enters the reflectometer through the corresponding branch of the splitter. In the reflectometer, there is a constant step-by-step control of the radiation intensity coming from all the rings.

The intensity of the registered light fraction will be proportional to the value of the measured parameter of the controlled environment, and the optical parameters of the radiation that returned and was recorded by the reflectometer will indicate the corresponding ring, that is, the amount of turbidity.

The bimetallic plate serves to create a preliminary bending of the light guide in the area of the primary light guide. The created bend initiates an additional leakage of radiation outside the light guide. As the temperature of the controlled environment increases, the curvature of the plate and previously created losses change. In this way, the information signal is automatically adjusted according to the temperature effect.

Further processing of the radiation will allow obtaining an electrical signal that will be proportional to the turbidity of the controlled environment.

Sources of information: 1. Optical-wave turbidity of technical media and oils / A.P. Markov and others -

National Academy of Sciences of Belarus; Institute of Metal Technology. - Minsk: Belarusian. Nauka, 2011. - 287 p. 2. Markov, A.P. Features of light-water turbidity // Journal of the Belarusian-Russian University. - 2012. - Mo 4 (37). - P. 93-103.

Z. Marukovich, B.Y., Sergeev, S.S., Markov, A.P., Zakharova, K.A. Schematic technique of perfecting turbidity measurements of liquid and gaseous media // Casting and metallurgy. - 2013. -

Mo Z (71). - P. 36-42. 4. Snyder, A., Love, D. Theory of optical waveguides. - M.: Radio and communication, 1987. - 656 p. 5. Busuryn, V.Y., Nosov, Y.R. Fiber-optic sensors: physical basis!, question! calculation and application. - M.: Znergoatomizdat, 1990. - 256 p. 6. Sandler, A.K. The sensitive element of the fiber-optic accelerometer based on sapphire glass // IH international scientific and methodical conference "Ship electrical engineering, electronics and automation", November 05-06, 2019: conference materials. -

Odesa: NU "OMA". - 2019. - P. 27-33.

Claims (1)

UTILITY MODEL FORMULA A fiber-optic turbidimeter consisting of a radiation source, photodetectors, a liquid crystal display processing module, combined into a reflectometer, a splitter, a primary light guide, and a base, characterized in that the base contains a fiber-optic sensing element that is a central light guide with a mirror layer of sapphire glass on the end, to which is connected a set of welded rings made of crown and heavy flint, which are located coaxially to the central light guide, which is connected to the primary light guide, which is mated with a bimetallic plate , a multiplexer/demultiplexer, a splitter, a block of optical spectral filters, a radiation source and photodetectors connected to a processor module with a liquid crystal screen, combined in the reflectometer. 1 2 3 4 5 oo Tk 9 Y i ! | 7 M V ! and shi shi i yi ; | | | No. 7 shows Z Bern nn 7 she en emo SHA Z Zlyy pen she ng yet IF Fig