JPH0127069Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to an infrared detector for detecting the temperature of an object to be detected using infrared rays.

(b) Prior Art Modern infrared detectors have a built-in infrared detector, for example, a pyroelectric type infrared detector.
Such an infrared detector has a characteristic of generating electric charge based on the amount of change in the amount of incident infrared rays, and the detection accuracy of the infrared detector improves as the amount of incident infrared rays changes more periodically. It is necessary to periodically interrupt the infrared rays incident on the detection object, and for this purpose, as shown in FIGS. 3 is placed.

However, such a chipper 3 has a large shape and has problems in terms of space.

Therefore, an infrared detector 4 as shown in FIG. 2 has been devised. In the figure, numeral 5 is a pyroelectric infrared detector made of lithium tantalate (LiTaO ₃ ) single crystal and generates a charge as a temperature signal according to the amount of change in incident infrared rays, and 6 and 7 are the infrared detectors, respectively. Front and back electrodes are formed on the front and back surfaces with nichrome vapor deposited films, 8 is a metal support made of copper, phosphor bronze, etc., and the back electrode 7 is placed on the support.
The infrared detector 5 is fixed to the upper surface of the support base 8 with a conductive adhesive 9 such as silver paste.

Reference numeral 10 denotes a storage body consisting of a metal cap 11 and a header 12, and the support base 8 is fixed on the header 12 inside the storage body. 13 is a ground terminal directly planted in the header 12,
The terminal is electrically connected to the back electrode 7 via the support base 8 and adhesive 9. Reference numeral 14 denotes a signal terminal implanted in the header 12 via an insulating material 15. The signal terminal is connected to the surface electrode 6 and is for extracting the electric charge generated in the detection body 5 to the outside. 16 is an opening formed in the cap 11 to allow infrared rays to enter the detection body 5 from the surface electrode 6 side; 17 is an infrared transmitting body that closes the opening; It is made of a silicon or germanium plate several 100 μm thick with high transmittance.

Reference numerals 18 and 19 indicate first and second planar surfaces arranged parallel to each other between the detection body 5 and the opening 16.
It is an opposing body. Such first and second opposing bodies 18, 19
As shown in FIGS. 3a and 3b, a plurality of first infrared rays are made of an infrared opaque material such as aluminum, gold, or silver and extend in a fan-shaped line in a direction parallel to the plane of the paper (FIG. 2). Non-infrared passing parts 20, 20... and second infrared non-passing parts 21, 21... are formed between each of the first infrared non-passing parts 20, 20... and second infrared non-passing parts 21, 21... A first infrared passing section 22, 22... and a second infrared passing section 23, 23... are formed between each of them.
The non-passing parts 20, 20... and 21, 21... and the passing parts 22, 22... and 23, 23... have the same size and shape, and have widths W ₁ and W ₂ of 100 μm, respectively.
It is 120 μm.

Reference numeral 24 denotes a first vibration mechanism for vibrating the first opposing body 18, and a second vibration mechanism 25 for vibrating the second opposing body 19 is formed behind this mechanism (FIG. 2). There is.

FIG. 4 shows details of the first and second vibration mechanisms 24 and 25, and 26 and 27 are rectangular parallelepiped-shaped first and second vibration mechanisms 26 and 27, respectively, with the first and second opposing bodies 18 and 19 fixed to their right ends. In the second vibrator, both the first and second vibrators are constructed as shown below. That is,
A conductor made of phosphor bronze, stainless steel, etc. serves as the central electrode 28, and on both sides of the electrode 28, polarized piezoelectric materials 29 made of barium titanate, lead zirconate titanate, etc. are arranged in the direction of polarization (arrow P). ) are the same (and are opposite for the first and second oscillators 26 and 27)
A surface electrode 30 made of silver or the like is formed on one surface of the piezoelectric body 29.

31 and 32 are first and second insulating stands 33 and 3 disposed on the header 12, respectively, for fixedly supporting the first and second vibrators 26 and 27 at their left ends;
Reference numerals 4 denote first and second vibrating terminals implanted in the header 12 via insulating materials 35 and 36, respectively, and the second vibrating terminal 34 has surface electrodes of the first and second vibrators 26 and 27, respectively. 30, 30... are lead wires 37, 37...
and the first vibration terminal 33 is connected to the first vibration terminal 33.
Center electrodes 28, 28 of second vibrators 26, 27 are connected by lead wires 38, 38.

Thus, a constant voltage of -20V is applied to the first vibration terminal 33, and + is applied to the second vibration terminal 34.
Voltages of 10V and -50V are applied periodically and alternately.

When such a voltage of +10V is applied, the outer piezoelectric body 29 of the first vibrator 26 contracts and the inner piezoelectric body 29 expands, so that the first vibrator 26
is bent in the direction of arrow A. Moreover, the second vibrator 27
In this case, the inner piezoelectric body 29 expands and the outer piezoelectric body 29 contracts, so that the second vibrator 27 is bent in the direction of arrow B.

On the other hand, when a voltage of -50V is applied to the second vibration terminal 34, the first and second vibrators 26 and 27 bend in directions B and A, respectively, contrary to the above description.

As a result, the first and second vibrators 26, 27
vibrate periodically in opposite directions, and based on such vibrations, the first infrared passing section 2 of the first opposing body 18
2, 22... and first infrared non-passing parts 20, 20...
and the second infrared non-passing portions 21, 2 of the second opposing body 19.
1... and the second infrared passing sections 23, 23... overlap each other, and the infrared passing sections 22, 22..., 2
3, 23...between each other and between infrared ray non-passing parts 2
The state in which 0, 20..., 21, 21... are superimposed is
repeated alternately, i.e. each infrared passing section 22,
The opening/closing states of 22... and 23, 23... change periodically, and infrared rays from the outside that have passed through the transmitting body 17 are intermittently incident on the detecting body 5, so that the detecting body 5 detects the amount of incident infrared rays. changes.

Here, in the above configuration, the second vibration terminal 34
and surface electrodes 30 of the first and second vibrators 26 and 27,
Four lead wires 37, 37, . . . are required between the terminals 30, 30, . Further, these lead wires 37, 37... are soldered to the surface electrodes 30, 30.
If the piezoelectric bodies 29, 29... are connected to..., the heat during soldering will cause undesirable distortion in the piezoelectric bodies 29, 29...
There is a drawback that the intermittent accuracy of infrared rays and, by extension, the accuracy of infrared detection decreases.

(c) Purpose of the invention The purpose of the invention is to simplify the wiring related to the vibrator and to configure the vibrator so that, for example, the piezoelectric material thereof is not distorted.

(d) Structure of the invention In order to achieve the above object, the structure of the present invention is such that the support base that supports the vibrator is conductive, and the support base also serves as a lead wire.

(E) Embodiment An infrared detector according to an embodiment of the present invention will be described below.
Incidentally, the same parts as in the conventional example are denoted by the same reference numerals, and the explanation thereof will be omitted.

In FIGS. 5 and 6, reference numeral 39 denotes a conductive support base made of an elastic conductive material such as phosphor bronze, which is placed on the header 12 via an insulator, and the upper surface of the support base is , a width W that is slightly smaller than the width of the first and second vibrators 26 and 27 (for example, 5
First and second grooves 40 and 41 having a diameter of 1 mm) are cut. The first and second vibrators 26 and 27 are press-fitted into the first and second grooves 40 and 41, respectively, so that the surface electrodes 30 and 30 are electrically connected to the support base 39. It matches. Also, the first and second
Center electrodes 28, 28 of vibrators 26, 27 are both bent inward and soldered to each other. Furthermore, the support stand 39 is connected to the second
connected to the vibration terminal 34 and connected to the central electrodes 28, 2.
8 is connected to the first vibration terminal 33 by a lead wire 53.

Therefore, with the above structure, the first and second vibrators 2
The number of wiring lines 6 and 27 has been significantly reduced, and there are no soldering points for surface electrodes 30, 30, . . . .

(f) Effects of the invention As is clear from the above explanation, according to the infrared detector of the present invention, infrared rays are interrupted by a pair of opposing bodies and a vibrator, so there is no need to use a motor, etc., and the device can be miniaturized. I can figure it out. Furthermore, since the support base that supports the vibrator is made conductive and conducts to the electrodes of the vibrator, the number of wires related to the vibrator can be reduced, wiring can be simplified, and the effects of heat caused by soldering to the vibrator can be reduced. Therefore, it is possible to prevent the occurrence of distortion and suppress the deterioration of infrared detection accuracy.

[Brief explanation of the drawing]

1A and 1B are a side view and a plan view of a conventional infrared detection mechanism, FIG. 2 is a sectional view of an improved conventional infrared detector, and FIGS. 3A and 3B are a plan view of the same essential parts, respectively. 4 is a view seen from the direction of the arrow in FIG. 2, FIG. 5 is a view corresponding to FIG. 4 of an infrared detector according to an embodiment of the present invention, and FIG. 6 is a front view of the same main part. 5... Infrared detector, 10... Storage body, 16... Opening, 18... First opposing body, 20, 20... First infrared non-passing part, 22, 22... First infrared passing part, 19
...Second opposing body, 21, 21...Second infrared ray non-passing section, 23, 23...Second infrared passing section, 26...First
Vibrator, 27...Second vibrator, 39...Conductive support base.

Claims (1)

[Scope of utility model registration request] An infrared detecting body that generates a charge according to the amount of change in incident infrared rays, a pair of opposing bodies arranged in the infrared incident area of the detecting body and having both an infrared passing part and an infrared non-passing part, which vibrate when an alternating current signal is applied. , comprising a vibrator for periodically changing the opening/closing state of the infrared passing portion of each of the pair of opposing bodies, and a conductive support base that supports the vibrator and is electrically connected to the electrodes of the vibrator. Infrared detector.