JP3353285B2 - Multi-point measurement device using radiation thermometer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multipoint measuring apparatus using a radiation thermometer for transmitting optical data received by a plurality of light receiving sensors through a single optical fiber.

[0002]

2. Description of the Related Art If any object is above absolute zero,
It emits energy of a certain wavelength. Since this radiant energy has a certain relationship with the temperature of the object, the temperature of the object can be known by detecting the radiant energy.
FIG. 3 shows an isothermal curve in a case where the horizontal axis represents the wavelength and the vertical axis represents the radiation intensity for a certain object. Integrating the radiant intensity for all wavelengths gives the radiant energy, which can be expressed as a function of temperature. Thus, the temperature corresponding to the radiant energy can be calculated from the radiant energy. The radiant energy obtained by integrating the radiant intensity for a certain wavelength range also indicates the temperature corresponding to the radiant energy. In FIG. 3, the temperature T1 can be calculated from the radiant energy obtained by integrating the isothermal curve of the temperature T1 in the wavelength range B over the range indicated by oblique lines.

A radiation thermometer is a device for measuring the temperature of an object using such a principle, and FIG. 4 is a diagram showing one example. Reference numeral 1 denotes a measurement target, and light from the measurement target 1 is condensed by a light receiving sensor 2 including a lens system. The light receiving sensor 2 is connected to a transmission optical fiber 4 by a connector 3,
The received light is transmitted to a light receiver 5 by a transmission optical fiber 4, and the light is converted into an electric signal by the light receiver 5, and the energy of the light is calculated to measure the temperature of the measurement target 1.

[0004]

When measuring the temperature of a large number of measurement objects with the radiation thermometer shown in FIG.
It is necessary to provide a radiation thermometer every time. When the measurement object 1 and the light receiver 5 are separated, the optical fiber 4 is connected to the measurement object 1
Must be laid in parallel. Optical fiber 4
Is capable of multiplex transmission of wavelengths, but if the wavelength range of wavelengths entering through each light receiving sensor 2 is the same, the wavelengths are mixed and it is difficult to separate the wavelengths for each measurement target 1 .

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and a specific wavelength range is determined for each measurement object so that a single optical transmission fiber can transmit data of many measurement objects. It is an object of the present invention to provide a multipoint measuring device using a radiation thermometer.

[0006]

According to the present invention, a plurality of objects to be measured (1a, 1b,
1c) and the measurement target (1a, 1b, 1c)
Simultaneously receiving light from the light-receiving sensor (2), provided for each light-receiving sensor (2), an optical filter for passing only the wavelength of the specific wavelength band for each light-receiving sensor (2)
(6a, 6b, 6c) and each optical filter (6a, 6a ).
b, 6c) , a multiplexer (8) for multiplexing the output light, a transmission optical fiber (4) for multiplexing the output light of the multiplexer (8) , and the transmission optical fiber the optical filter emitted light (4) (6a, 6b, 6c) demultiplexer for demultiplexing a specific wavelength range of each (9), specific wavelength demultiplexed by the該分duplexer (9) Receiver that calculates the temperature from the wavelength of the region
(5) and, with a multi-point measuring apparatus using a radiation thermometer, wherein provided that.

[0007]

In the invention having the above structure, a plurality of measurement objects (1
a, 1b, 1c) light in a wide wavelength range entering the light receiving sensor (2) provided for each, the respective light receiving sensors (2) an optical filter for passing only light of specific wavelength range (6a, 6
b, by 6c), respectively become a wavelength characteristic in the wavelength range, it is multiplexed by a multiplexer (8), transmitting a number of data of the measurement object (1) a single transmission optical fiber (4) Can be. Light transmitted from the transmission optical fiber of one (4), by the demultiplexer (9), is separated into wavelength for each original wavelength range, the energy of each wavelength band by the light receiver (5) Calculate and measure (1a, 1b, 1
c) The temperatures for each can be obtained simultaneously .

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing the configuration of the embodiment. Reference numeral 1 denotes a temperature measurement target. It is assumed that the temperatures of a plurality of (three in this embodiment) measurement targets 1 are measured simultaneously. Reference numeral 2 denotes a light receiving sensor, which includes a lens system for receiving light emitted from the measurement target 1 and a lens system such as an aperture. The light receiving sensor 2 has a built-in optical filter 6 that allows only light in a specific wavelength range to pass through for each of the light receiving sensors 2, and emits only wavelengths in a specific wavelength range of light received by the lens system. Each light receiving sensor 2 is connected to a multiplexer 8 by a connection optical fiber 7. The multiplexer 8 multiplexes the wavelengths in the respective wavelength ranges so that the wavelengths can be multiplexed and transmitted in the optical fiber. One transmission optical fiber 4 is connected to the multiplexer 8, and multiplexes the multiplexed light. The exit end of the transmission optical fiber 4 is connected to a demultiplexer 9, and demultiplexes the multiplexed light into light for each wavelength range before multiplexing. The same number of connection optical fibers 10 as the number of light receiving sensors 2 are provided in the demultiplexer 9 and connected to the photodetectors 5 respectively. Is transmitted to the light receiver 5 by the connection optical fiber 10. The light receiver 5 calculates the radiant energy for each wavelength range, and calculates the temperature for each wavelength range. Thereby, the temperature measurement for each measurement object 1 is performed.

In FIG. 1, the hatched portions a, b, and c of the radiation temperature curve 11 shown below the optical filter 6 represent energy in a wavelength range that each optical filter 6 passes. The hatched portions a ', b', and c 'of the radiation temperature curve 11 shown below each connection fiber 10 on the right side show the energy in each wavelength band separated by the demultiplexer 9, and both are due to transmission. Except for the loss, they are equal (a = a ', b = b', c = c ').

FIG. 2 shows each of the measurement objects 1a, 1b, 1 in FIG.
c is a diagram showing the wavelength range and the radiation intensity of the wavelength passing through each of the optical filters 6a, 6b, and 6c when the temperature is different from T3, T2, and T1 in the same object. Represents In the case where the temperature is the same object and the measurement object 1a is T3, 1b is T2, and 1c is T1, the energy passing through each wavelength range b1, b2, b3 is represented by hatched portions a, b, c. The temperature T3 of the measurement target 1a is calculated from the energy passing through the wavelength range b1. The same applies to the other measurement targets 1b and 1c, and the energy of the measurement target 1b having the temperature T2 is obtained from the hatched portion b, and the temperature T
The measurement object 1c having 1 is obtained from the shaded portion c. Each of the wavelength ranges b1, b2, and b3 has the same width and includes different wavelengths. The width of the wavelength range can be narrowed to about 10 nm, and the wavelength of light incident on the optical filter 6 can be divided into a large number of wavelength ranges since it is several hundred nm even if narrow. However, when the width of the wavelength range is reduced, the measurement accuracy is reduced, and therefore, it is necessary to determine the wavelength range passing through the optical filter 6 in consideration of the accuracy.

[0011]

As is apparent from the above description, the present invention provides an optical filter for passing a wavelength in a specific wavelength range for each light receiving sensor so that light from a plurality of temperature measuring objects can be different from each other. , And transmission is performed by one optical fiber, so that the data transmission path is simplified.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an embodiment.

FIG. 2 is an explanatory diagram in a case where different wavelength ranges are set for each measurement target and different temperatures of the same object are measured.

FIG. 3 is a diagram illustrating a relationship between a wavelength of light emitted at each temperature of an object and a radiation intensity.

FIG. 4 is a diagram illustrating an example of a configuration of a radiation thermometer.

[Explanation of symbols]

 1, 1a, 1b, 1c Measurement target 2 Light receiving sensor 3 Connector 4 Transmission optical fiber (optical fiber) 5 Optical receiver 6, 6a, 6b, 6c Optical filter 7, 10 Connection optical fiber 8 Multiplexer 9 Duplexer 11 Radiation temperature curve a, b, c, a ', b', c 'Shaded area b1, b2, b3, B Wavelength range T1, T2, T3, T4 Temperature

Claims (1)

(57) [Claims] 1. A plurality of measurement objects (1a, 1b, 1c)
Arranged whenever the measured (1a, 1b, 1c) at the same time as the light-receiving sensor for receiving (2) the light from, provided for each light-receiving sensor (2), each of the light receiving sensor
(2) an optical filter (6a, 6b, 6c) for passing only a wavelength in a specific wavelength range, and a multiplexer (8) for multiplexing light emitted from each optical filter (6a, 6b, 6c). One transmission optical fiber (4) for multiplex transmission of the output light of the multiplexer (8) ; and the optical filter for outputting the output light of the transmission optical fiber (4).
(6a, 6b, 6c) demultiplexer for demultiplexing a specific wavelength range of each (9), than the wavelength of the specific wavelength band demultiplexed by the該分duplexer (9),
A multipoint measuring device using a radiation thermometer, comprising: a light receiver (5) for calculating a temperature.