JPS63286729A - Thermopile detector - Google Patents

Abstract

PURPOSE:To always execute a correct measurement, even if an ambient temperature is varied, by providing two temperature sensing elements in the vicinity of a cap for containing a thermopile element, and a heat sink, and correcting the output of the thermopile element by its output. CONSTITUTION:On the upper part of a heat sink 5, a thermopile element 6 is provided, and on the upper part of a cap 3, a first temperature sensing element 7 is provided. Also, in the vicinity of the heat sink 5, a second temperature sensing element 8 being the same as the element 7 is provided, and each output of the elements 6-8 is brought to an arithmetic processing by a measuring means 9. That is, when an output of the element 6, an output of the element 7, and an output of the element 8 are denoted as e1, e3 and e2, respectively, when the outputs e2, e3 are equal, the output e1 of the element 6 goes to measured value output e0. Also, when an ambient temperature rises and goes to e3>e2, e3-e2 corresponding to a temperature difference is subtracted from the output e1 and corrected, by which even if a temperature difference caused by an ambient temperature change is generated, the measurement always can be executed exactly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermopile detection device that detects radiant energy using a thermopile element.

(Prior art 1) A thermopile element is housed in a package, and is used to collect and detect the radiant energy from the Song to be measured using an optical system and measure its temperature.

This thermopile detector is usually fixed to a heat soaking block or the like, detects the temperature of the heat soaking block using a temperature sensor, and corrects errors in measured values due to room temperature changes.

[Problems to be solved by this invention] However,
The hot junction of the light-receiving part of the thermopile element receives not only the infrared rays that pass through the window provided in the key/button of the package, but also heat radiation from the window material and the inside of the cap, leading to measurement errors. was.

In other words, if the ambient temperature suddenly changes, the change is transmitted to the heat soaking block, and the cap part with a relatively small heat capacity changes temperature first, while the stem (base) part, which holds the element and has a relatively large heat capacity, lags behind. occurs. For this reason,
The hot junction of the thermopile element reacts to infrared radiation from the cap or window, causing a drift phenomenon in the measured value.

In view of the above points, the purpose of this section is to provide a thermopile detection device that always provides correct measured values even if the ambient temperature changes.

[Means for Solving Problem 1] This invention provides a first temperature-sensitive element, a heat sink or a cold junction part, and a second temperature-sensitive water element in the vicinity of the upper part or window material of the cap that houses the thermopile element. established,
This is a thermo t'< ile detection device in which the output of the thermopile element is corrected by the output of these temperature sensing elements.

[Example] FIG. 1 is a configuration explanatory diagram showing an example of this construction.

In the figure, 1 is a stem (base) having several lead bins 28 to 2'', and a cap 3 with a window material 4 fixed with an adhesive 4a is provided on the top. Inside, a hollow ring-shaped heat sink 5 is provided, which is connected to and covered by the upper end of the lead bin 2a12b, and on the top thereof, a thermopile element 6 is provided, in which the center is a hot contact part 6a as a light receiving part, and the periphery is a cold contact part 6b. A detection signal is taken out to the outside via the dowels 2a and 2b.Then, a first temperature sensing element 7 such as a thermistor, a resistance element, a thermocouple, etc. is placed on the top of the cap 3 or near the window material 4.
is provided, and connected to the lead bins 2C and 2d via lead wires to take out signals to the outside.Also, near the cold junction portion 6b of the heat sink 5 or the thermopile cord 6, a temperature sensing element similar to the first temperature sensing element 7 is provided. A second riA temperature element 8 is provided, and is connected to lead bins 2e and 2f via lead wires to output signals to the outside. Each output of the thermopile 6, the first temperature sensing element 7, and the second temperature sensing element 8 is processed by a measuring means 9 including the necessary measuring circuit, and the correct output of the thermopile cable 6 is extracted. .

Here, if the output of the sensor pile element 6 is 01, the output of the first temperature sensing element 7 is e2, and the output of the second temperature sensing element is 03, then the first and second temperature sensing elements 7.8 When the outputs e2 and e3 are equal, the output e1 of the thermopile element 7 directly becomes the measured value output eQ. Also, if the surrounding Wli increases, e2>e3, and the amount e2-0 corresponds to this difference.
3 is subtracted from the output e1 of the thermopile element 6 by the measuring means 9 to correct it.

That is, if f, (l is a predetermined function, output 0o=f
By performing the following equation (e+) Q<e2 e3)c7), disturbances in thermal stability due to changes in the same temperature can be grasped in a fixed manner, and drifts in measured values can be compensated for.

Note that the temperature sensing element 7.8 of the first cap 12 may be formed of a thin film on the cap 7, on and near the cold contact portion 6b.

[Effect of the invention 1 As described above, the present invention provides a cap for storing a thermopile element, a heat sink on a stem, etc.
Since the output of the thermopile element is corrected using the output of two temperature sensing elements, it is possible to correct even if there is a temperature difference between the cap part and the heat sink part due to the same temperature change, etc. Therefore, accurate measurements are always possible.

[Brief explanation of drawings]

FIG. 1 is a configuration explanatory diagram showing one embodiment of the present invention.

Claims (1)

[Claims] 1. A thermopile element provided on the heat sink,
A cap and a stem having a window material in the upper part that accommodates the thermopile element, a first temperature sensing element provided at the top of the cap or near the window material, and a first temperature sensing element provided at and near the cold junction of the heat sink or thermopile element. What is claimed is: 1. A thermopile detection device comprising: a second temperature-sensing element, and a measuring means for correcting the output of the thermopile element with the output of the first temperature-sensing element and the output of the second temperature-sensing element.