JPH05157629A - Radiation thermometer - Google Patents

Abstract

PURPOSE:To measure the temperature of an object to be measured over a wide temperature range from a low temperature to a high temperature. CONSTITUTION:A detecting element 7 which detects the radiant energy of an object to be measured is constituted by putting together a first and second detecting elements 7a and 7b. The element 7b detects the radiant energy of the wavelength which is transmitted by the element 7a. The detecting signals of the elements 7a and 7b are converted into temperatures by means of an arithmetic means 11, but, since a setting means 15 can freely select either one of the elements 7a and 7b, the elements 7a and 7b can individually detect different temperature ranges with different wavelengths and the temperature measuring range of the detecting element 7 can be expanded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation thermometer for measuring the temperature of an object to be measured by the radiant energy.

[0002]

2. Description of the Related Art The structure of a conventional radiation thermometer is shown in FIG.
The radiant energy of the object to be measured is detected by the detection element 40 via a rotary disc 42 having a plurality of filters 41 having different transmission wavelengths.
Detected in. The detection element 40 is composed of a pyroelectric element, a thermoelectric detector such as a thermopile, or a photoelectric detector such as PbS, Si, or Ge. The turntable 42 is rotated by the motor 42a, and the detection signal of the detection element 40 is input to the calculation means 45 via the amplifier 43 and the A / D converter 44.

Further, the position of each filter 41 on the turntable 42 is detected by the synchronizing signal generator 46 and calculated by the calculating means 45.
Entered in. Therefore, the calculation means 45 can obtain the detection signal for each transmission wavelength in synchronization with each filter 41. The calculation means 45 calculates and outputs the temperature of the object to be measured by measuring the ratio of radiant energy detected through each filter 41.

[0004]

However, the detection element used in the conventional radiation thermometer has a limited detection wavelength range according to its type. Therefore, a single device can only measure the temperature within the limited range of the detection element, and the application is specified.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a radiation thermometer capable of measuring temperature over a wide range.

[0006]

In order to achieve the above object, the radiation thermometer of the present invention separates the radiant energy emitted from the object to be measured into the radiant energy of a specific wavelength,
In a radiation thermometer that detects radiant energies of a plurality of wavelengths obtained separately and calculates and outputs the temperature of an object to be measured, first and second detection elements 7 having different detection wavelengths
a and 7b are provided in an overlapping manner, and the first detection element 7a on the front side of the optical path is made of a material that transmits the light of the detection wavelength of the second detection element 7b.
a hybrid detection element 7 for outputting a detection signal from each of a and 7b, and a plurality of spectroscopic means such as a plurality of transmission filters 5 and the like capable of transmitting the wavelengths of the radiant energy of the detection wavelengths of the first and second detection elements 7a and 7b, respectively. , The first and second detection elements 7
an arithmetic means 11 for selecting a detection signal when transmitted through a plurality of transmission filters 5 as a spectroscopic means corresponding to a and 7b, and outputting the temperature of the object to be measured from the plurality of detection signals;
Setting means 15 for selecting the detection of the radiant energy by one of the first and second detection elements 7a and 7b as required.
It is characterized by having and.

[0007]

The radiation energy emitted by the object to be measured is detected by the first detection element 7a of the hybrid detection element 7 after passing through the plurality of transmission filters 5 having different wavelengths. The first detection element 7a outputs detection signals corresponding to light having different wavelengths, and is calculated by the calculation means 11 to obtain the temperature of the object to be measured. Further, behind the first detecting element 7a, a second detecting element 7b for detecting the radiant energy transmitted through the first detecting element 7a is provided, and the radiant energy having a wavelength different from that of the first detecting element 7a is detected.

Further, the transmission filter 5 is provided with a plurality of transmission filters having different wavelengths corresponding to the second detection element 7b. Therefore, the plurality of transmission filters 5 are
Each of the first and second detection elements 7a and 7b has a transmission wavelength around the detection wavelength. Then, by selecting the desired first or second detection element 7a or 7b by the setting means 11, the transmission filter 5 corresponding to the radiant energy of the wavelength which either the first or second detection element 7a or 7b has is selected. The detection wavelength band can be changed only by this switching, and the temperature measurement range can be changed.

[0009]

FIG. 1 is a diagram showing an embodiment of a radiation thermometer of the present invention. A lens 1 is provided on the front side of the device, and a rotating disk 2 is provided behind the lens 1. The rotating disk 2 has its center fixed to the shaft of the motor 3 and rotates at a constant speed, and further has a plurality of transparent windows 4 formed at positions equidistant from the center of rotation. In this transmission window 4, a transmission filter 5 as a plurality of spectroscopic means having different transmission wavelengths, respectively.
(5a to 5i) are provided. Behind the rotating disk 2, a branching means 6 composed of a half mirror is provided, and the branching means 6 changes the radiant energy different from each other.
It leads to the hybrid detection elements 7 and 8 of a place.

The hybrid detecting elements 7 and 8 are formed by overlapping first and second detecting elements 7a and 7b made of different materials, respectively.
b detects the light transmitted through the first detection elements 7a and 8a, respectively. That is, the first detection elements 7a and 8a provided on the incident side (front side of the optical path) respectively have at least the detection wavelength band of the second detection elements 7b and 8b (especially the detection peak wavelength).
It is necessary to use a material whose part is transparent.

For example, the hybrid detection element 7 is made of Si having a detection peak wavelength of 0.84 μm and a transmission wavelength of 1 to 20 μm.
And a second detection element 7b formed of PbS having a detection peak wavelength of 2.3 to 2.7 μm overlap each other. The hybrid detection element 8 has a detection peak wavelength of 5.4 μm and a transmission wavelength of 2 to 25 μm.
The first detection element 8a formed of Ge of m and the second detection element 8b formed of a pyroelectric element (PE) having a detection wavelength of 1 to 20 μm are overlapped with each other. In addition, if Si is used for the first detection elements 7a and 8a, the second detection elements 7b and 8b
Can be TP, Ge, PE. Also,
The first and second detection elements 7a, 8a, 7b, 8b are respectively
The hybrid detection elements 7 and 8 can be configured by arbitrarily combining a thermoelectric detector and a photoelectric detector.

Each of the transmission filters 5 transmits a specific wavelength. For example, the transmission filters 5a to 5c are the first detection element 7a (Si of the hybrid detection element 7).
Manufactured by the company), 5a transmits light of 0.65 μm, 5b transmits 0.9 μm, and 5c transmits light of 1.0 μm. Then, the transmission filter 5d (1.4 μm),
5e (1.6 μm) is a transmission filter for the first detection element 8a (made of Ge) of the hybrid detection element 8. Furthermore, the transmission filter 5f (2.1 μm) and 5 g (2.3
μm) is the second detection element 7b of the hybrid detection element 7.
It is a transmission filter for (made of PbS). The transmission filters 5h (3.4 μm) and 5i (5.0 μm) are transmission filters for the second detection element 8b (made of PE) of the hybrid detection element 8. With the transmission filter 5 configured in this way, light of different wavelengths is transmitted and supplied to the hybrid detectors 7 and 8. Instead of the transmission filter 5, another spectroscopic means such as a diffraction grating may be used to extract light of a predetermined wavelength and supply it to the subsequent stage.

The detection signals of the hybrid detection elements 7 and 8 are output to the calculation means 11 via the amplifier 9 (9a to 9d) and the A / D converter 10 (10a to 10d), respectively. By operating the setting means 15 such as a key, the computing means 11 selects one of the outputs of the hybrid detection elements 7 and 8 to take in one of the first and second detection elements 7a, 7b, 8a and 8b. Here, the setting means 15 specifies a measurable temperature range corresponding to the wavelength range of each of the detection elements 7a, 7b, 8a, 8b. Further, the rotational position of the rotary disk 2, that is, the position of each transmission filter 5 is detected by the synchronization signal generator 12 and input to the arithmetic means 11.

Then, the calculating means 11 obtains the transmitted light of the transmission filter 5 corresponding to the selected detection element, so that the desired transmission filter 5 is detected during the rotation of the rotary disk 2 based on the detection of the synchronizing signal generator 12. Captures the detection signal when is located on the optical path. For example, when obtaining the detection signal by the first detection element 7a of the hybrid detection element 7 formed of Si, the transmission filters 5a (0.65 μm), 5b
(0.9 μm), 5c (1.0 μm) portions are repeatedly fetched with detection signals when they are positioned on the optical path, and the temperature is calculated from the individual detection signals of these transmission filters 5a, 5b, 5c or their ratio. Output.

When the setting of the setting means 15 is changed to measure the temperature using the detecting element 7b, this light is transmitted based on the transmitted light of the transmission filters 5f (2.1 μm) and 5 g (2.3 μm). The temperature is calculated and output from a single detection signal corresponding to or the ratio thereof. In this way, by selecting the transmission filter 5 corresponding to the detection wavelength of each of the detection elements 7a, 7b, 8a, 8b, the calculation means 11 changes the measurement range to change the temperature of the object to be measured. It can be measured and can be measured in multiple ranges from low temperature to constant temperature.

In the above-described embodiment, the light split by the spectroscopic means 6 is used to obtain the detection output of a total of four detection elements by the two hybrid detection elements 7 and 8. However, the branching means 6 is used. Instead, one hybrid detection element 7 may be used to obtain two detection outputs, and in this case as well, a plurality of measurement ranges corresponding to the detection wavelengths of the detection elements can be set, and a wide range as in the above-described embodiment can be set. Temperature measurements can be made.

[0017]

According to the present invention, since two detection elements each having a different detection wavelength are superposed, it is possible to obtain detection signals at different detection wavelengths only by disposing the detection elements at one location. The entire device can be miniaturized without taking up space for installing the detection element. Further, the setting means can change the measurement temperature range of the object to be measured corresponding to the detection signals of the plurality of detection elements, and can perform wide range temperature measurement from low temperature to high temperature.

[Brief description of drawings]

FIG. 1 is a diagram showing a radiation thermometer of the present invention.

FIG. 2 is a diagram showing a conventional radiation thermometer.

[Explanation of symbols]

2 ... Rotating disk, 5 (5a-5i) ... Transmission filter (spectral means), 6 ... Dividing means, 7, 8 ... Hybrid detection element, 7a, 8a ... 1st detection element, 7b, 8b ... 2nd detection element, 9 (9a to 9d) ... amplifier, 10 (10a to 10d)
d) ... A / D converter, 11 ... arithmetic means, 15 ... setting means.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yukio Matsui 32-8 Kumano-cho, Itabashi-ku, Tokyo

Claims (1)

[Claims] 1. The radiant energy emitted from the object to be measured is separated from the radiant energy having a specific wavelength, the radiant energy having a plurality of wavelengths obtained by the separation is detected, and the temperature of the object to be measured is calculated. In the radiation thermometer that outputs, the first and second detection elements (7a, 7
b) are provided in an overlapping manner, and the first detection element (7
a) is a hybrid detection element (a) that outputs a detection signal from each of the first and second detection elements (7a, 7b) by being made of a material that transmits light of the detection wavelength of the second detection element (7b). 7), a spectroscopic unit (5) for taking out radiant energy of the detection wavelength of the first and second detection elements (7a, 7b), and a spectroscopic unit corresponding to the first and second detection elements (7a, 7b), respectively. A radiation thermometer, comprising: a calculating means (11) for selecting a detection signal from the means (5) and outputting the temperature of the object to be measured from the plurality of detection signals.