JPS6344134A - Image guide type radiation thermometer - Google Patents

Abstract

PURPOSE:To enable the measuring of temperature in a very small area accurately, by using an image guide for transmission of infrared rays to remove infrared rays radiated from outside the area to be measured. CONSTITUTION:Infrared rays radiated from an area 1 to be measured forms an image with an objective lens 6 on an incident end face 12 of an image guide 10. The image thus formed is transmitted as image to an emission end face 11 thereof with the image guide 10 and then, enters a mask filter 13. On the other hand, infrared rays radiated from outside the area 1 being measured are intercepted with a non-transmitting section 14 with a remarkably low infrared rays transmission factor of the mask filter 13 so that only the infrared rays radiated from the area 1 being measured enters an opto-electrical transducer element through a transmitting section 15 with a high infrared rays transmission factor to be converted into an electrical signal and displayed with a linearizer, a display circuit or the like. This enables the measuring of temperature in a very small area accurately.

Description

[Detailed description of the invention] (Industrial use 5f) Unemitted IN+ relates to a radiation thermometer that uses an image guide in the optical system, and the area of the target area is larger than the field of view of a single radiation thermometer. This allows highly accurate temperature measurement even in narrow spaces.

(Prior Art) Conventionally used radiation thermometers are roughly divided into the following two types.

One is the lens method, as shown in Fig. 2, in which infrared rays emitted from the measurement area 1 are condensed by a lens 2, and then converted into 1, +? by photoelectric conversion 7kY-3. After converting the temperature into a temperature signal, the linearizer 4 and display circuit 5 display the temperature.

The other one is an optical fiber type, in which the infrared rays emitted from the measurement area 1 are focused by a lens 6 as shown in No. 3b4, transmitted through an optical fiber 7, and transferred to a photoelectric conversion element. After the temperature is converted into an electric signal by 3, the temperature is displayed by a linearizer 4 and a display circuit 5.

Compared to the lens method, the optical fiber/head method allows the head that collects infrared rays to be brought closer to the constant Δ area 1, so it is less susceptible to disturbance from surrounding infrared light and dust. It has characteristics.

(IF of the prior art, 1 problem) As shown in Figures 2 and 3, is the area of the measurement area l visible to the radiation thermometer? There is no problem if it is sufficiently large compared to A, but
As shown in Fig. 4, if it is smaller than the visual field 51A, the zero constant area l
There is a problem that a difference occurs in the detected temperature when the sensor receives infrared radiation from the surroundings or when the detection distance changes.

Further, in such a case, there is a problem that it is difficult to align the optical axes of the measurement area 1 and the radiation thermometer.

(Objective of the invention) The purpose of the unreleased I51 is to improve the optical fiber type radiation thermometer and to improve its visibility! Even when measuring the temperature of a measurement area l narrower than fA, infrared light U emitted from outside the measurement area l
S sound) is removed to improve measurement accuracy, and the measured area 1
The objective is to facilitate alignment of the optical axis between the radiation thermometer and the radiation thermometer.

(F-stage to solve the problem) The unreleased ImageGa f-do method radiation thermometer is a radiation thermometer that measures temperature by detecting infrared rays. image guide 10
using the exit end face 11 side or the entrance end face 1 side of the same guide 10.
A mask filter 13 is inserted on the second side to block infrared rays from outside the target fixed area l.

(Function of the Invention) In the unreleased mode, infrared rays emitted from the measurement area 1 shown in FIG. This image is transmitted as an image by the image guide 10 to its output end face 11, and then enters the mask filter 13. Only the infrared rays emitted from the measurement area l are blocked by ′rlLj with high infrared transmittance.
! The signal passes through the first section 15 and enters the photoelectric conversion element 3, where it is converted into an hypochondriacal signal and displayed on a linearizer, display circuit, etc.

(Embodiment) In the unreleased 1!1, optical fiber bundles A regularly arranged, ie, image guides 10, are used for transmitting infrared rays for the purpose of transmitting images.

The mask filter 13 has an infrared transmittance of 7i1. It is composed of a non-transparent part 14 with a low transmittance and a transparent part 15 with a high infrared transmittance, and the shape of the transparent part 15 is similar to the shape of the region 1 to be measured. As a result, when the orientation and direction of the objective lens 6 is adjusted, the fixed area l to be exposed enters the transmitting portion 15 by T degrees.

Further, in the present invention, a mirror or a half mirror may be inserted between the mask filter 13 and the photoelectric conversion element 3 to perform optical axis alignment and humidity measurement almost simultaneously.

(Effect of the invention) Unreleased II has the following effects.

(1) Since the image guide 10 is used and the mask filter 13 is used to exclude infrared light outside the measurement area, the temperature of a minute area can be accurately measured.
can do.

(2) Since the image guide IO was used, the measurement area 1
The optical axes can be aligned with the radiation thermometer using the i-view, making it very easy to align the optical axes.

(3) Since the image guide 10 is used to transmit infrared light (because the fiber is heat resistant), the open fiber 1 can be brought close to the measurement area l. Therefore, infrared light (noise) from outside the region to be measured l enters, making it possible to perform highly consistent measurements.

(4) Since the image guide IO is used for the transmission of infrared light (because the optical fiber has IIr iA properties), the optical path of the optical fiber can be freely selected, and therefore the narrow J↓ or bend can be freely selected. It also becomes easier to place it in a location.

[Brief explanation of the drawing]

Fig. 1 is a diagram II showing an example of the radiation thermometer of the present invention, and Fig. 2 is a diagram II showing a conventional lens-type radiation thermometer.
, Fig. 3 is an explanatory diagram of a conventional optical fiber type radiation thermometer, and Fig. 4 is an explanatory diagram of a conventional optical fiber type radiation thermometer, when the area to be measured is smaller than the field of view of the radiation thermometer. FIG. 1 is a measurement area 10 is an image guide 11 is an output end face 12 is an entrance end face 13 is a mask filter

Claims (1)

[Claims] In a radiation thermometer that measures temperature by detecting infrared rays, an image guide is used to transmit infrared rays, and a mask filter is inserted at the output end or input end of the guide to block infrared rays from outside the measurement area. An image-guided radiation thermometer characterized by: