JPH09305871A - Infrared detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set the wide angle of a detection range while suppressing the cost without expanding an infrared detector by providing a wing-shaped infrared reflector between a condenser lens and the infrared detector. SOLUTION: A condenser lens 3 is composed of assembly of plural lenses so as to converge infrared rays in the front and side face directions of an infrared detector 1. An infrared reflector 7 is arranged between the front field of view of the infrared detector 1 and the condenser lens 3. The infrared reflector 7 is worked and formed in the shape of wing. The infrared rays converged by the condenser lens 3 inside the field of view of the infrared detector 1 are passed through a cut part 9 of the infrared reflector 7 and made incident to a detection element 6. The infrared rays in the almost side face direction of the infrared detector 1 are converged through the condenser lens 3, afterwards, reflected by the infrared reflector 7 and made incident to the detection element 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infrared detecting device, and more particularly to a substantially omnidirectional detecting infrared detecting device capable of detecting even outside the visual field of an infrared detector.

[0002]

2. Description of the Related Art Generally, an infrared detecting device is mounted on a wall surface or a ceiling of a building and used mainly for detecting a human body such as an intruder alarm device or an automatic door.

FIG. 7 is a sectional view showing a conventional infrared detecting device. Here, 1 is an infrared detector, 2 is a printed circuit board on which peripheral circuits are mounted, 3 is a condenser lens, 4 is a case, 5
Is a metal cap, and 6 is a detection element.

The infrared detector 1 is housed in a printed circuit board 2 on which peripheral circuits are mounted, a case 4 and a condenser lens 3. An infrared detector having such a structure is disclosed in Japanese Patent Laid-Open No.
No. 2-147325.

[0005]

The infrared detector 1 housed in the case 4 receives the infrared light condensed through the condenser lens 3 by the detection element 6. In this case, the detection range of the infrared detection device is limited by the viewing angle that is roughly determined by the distance between the opening area of the metal cap 5 of the infrared detector 1 and the detection element 6. As shown in the conventional example of FIG. 2, the viewing angle is about 100 ° in front of the infrared detection device, and the detection distance at this time is about 3 m. Therefore, the area with a larger angle is outside the field of view (non-detection range). Was there.

When an infrared detector is attached to the wall of a building, a wider angle detection range is required. As a method for solving this problem, Japanese Patent Application Laid-Open No. 1-2217221 discloses an infrared detecting device provided with an optical component having a Fresnel lens function and a mirror function at the front of a detector. However, although a wide angle can be detected, such an optical component is expensive and the cost of the entire device is high. In addition, there is a defect that the entire device becomes large.

Therefore, the present invention has been made in order to solve the above-mentioned problems, and it is possible to set the detection range to a wide angle without increasing the size of the conventional structure and relatively suppressing the cost. An object of the present invention is to provide a detection device.

[0008]

An infrared detector according to the present invention comprises an infrared detector and a condenser lens, and the condenser lens is arranged both inside and outside the visual field of the infrared detector. An infrared reflector is provided between the condenser lens and the infrared detector, and the infrared reflector is formed into a wing shape and has a cut portion in front of the field of view of the infrared detector. It is an infrared detector.

Another infrared detection device according to the present invention is an infrared detection device in which the infrared detector comprises a pyroelectric detection element.

In another infrared detector, the condenser lens is composed of an assembly of a plurality of lenses, and the infrared rays condensed by the lenses in the field of view of the infrared detector are made incident on the infrared detector through the ablation section, It is an infrared detection device that reflects infrared rays collected by a lens outside the field of view of the infrared detector to an infrared reflector and makes them enter the infrared detector.

Still another infrared detecting device is an infrared detecting device in which an infrared reflector is arranged in a wing shape substantially symmetrically with respect to the center of the infrared detector.

Further, it is an infrared detecting device in which each of the right and left sides of the infrared reflector has a parabolic curved surface.

[0013]

1 is a sectional view showing an infrared detecting device according to the present invention. Here, 1 is an infrared detector, 2
Is a printed circuit board on which peripheral circuits are mounted, 3 is a condenser lens,
Reference numeral 4 is a case, 5 is a metal cap, 6 is a detection element, 7 is an infrared reflector, 8 is a fixed portion, and 9 is a cutout portion.

The infrared detector 1 is mounted on a printed circuit board 2 together with peripheral circuits and is housed in a space formed by a case 4 and a condenser lens 3.

The condenser lens 3 is composed of an assembly of a plurality of lenses so that the infrared rays in the front and side directions of the infrared detector 1 can be condensed. By providing a plurality of lenses, the focus and incident direction of infrared rays can be adjusted, and infrared rays can be reliably incident on the detection element 6.

An infrared reflector 7 is arranged in front of the field of view of the infrared detector 1 and between the condenser lens 3 and
The fixing portion 8 is fixed to the case 4 by an appropriate means such as adhesion.

The infrared reflector 7 is formed into a wing shape substantially symmetrically with respect to the front surface of the infrared detector, and a cutout portion 9 is formed at a part in front of the visual field of the infrared detector 1.
It has. The infrared rays condensed by the condenser lens 3 within the field of view of the infrared detector 1 pass through the cutout portion 9 and enter the detection element 6. Each of the left and right members of the infrared reflector 7 has a parabolic curved surface. By forming a parabolic curved surface, infrared rays can be efficiently incident on the detection element 6.

The detection element 6 comprises a heat ray sensing element typified by a pyroelectric detection element, and is housed in a metal cap 5 having an opening through which infrared rays enter. The detection range of the infrared detection device is limited by the viewing angle that is roughly determined by the opening area of the metal cap 5 and the distance between the metal cap 5 and the detection element 6.

The infrared rays in the substantially lateral direction of the infrared detector 1 limited by the viewing angle are condensed through the condenser lens 3 and then reflected by the infrared reflector 7 to the detection element 6 of the infrared detector 1. Can be incident.

By providing the infrared reflector 7 having the excision portion 9, it is possible to realize an infrared detecting device for detecting infrared rays in almost all directions (viewing angle of about 180 °). As a result, it is possible to send out a warning signal to an alarm device or an opening / closing signal of an automatic door by detecting the infrared rays emitted from the human body in the front and side detection areas of the wall on which the infrared detection device is installed. it can.

[0021]

The present invention will be described in more detail with reference to Examples.

(Embodiment 1) FIG. 3 is a perspective view (a) and a front view (b) showing an embodiment of the infrared reflector 7 in FIG.

As explained in FIG. 1, the infrared reflector 7 is provided between the condenser lens 3 and the infrared detector 1,
As shown in the perspective view of FIG. 3 (a), it is formed into a wing shape substantially symmetrically. Further, the cutout portion 9 of the infrared reflector 7 is provided in the central portion corresponding to the root of each of the wing-shaped left and right members, and is attached so that infrared rays from substantially the front direction of the infrared detection device can pass therethrough.
(B) The portion surrounded by the dotted line in the front view shows the position of the infrared detector 1.

As a result, the infrared rays from the substantially front direction of the infrared detection device are directly incident on the infrared detector 1 after being collected by the lens, and the infrared rays in the substantially lateral direction of the infrared detection device are collected after the lens. It can be reflected and incident on the infrared reflector 7. As shown in the embodiment of FIG. 2, the viewing angle was expanded to about 180 ° in front of the infrared detection device. In addition, the viewing angle of the infrared detection device (about 100
The detection distance in °) is equal to or more than the conventional one.

(Embodiment 2) FIG. 4 is a perspective view (a) and a front view (b) showing another embodiment of the infrared reflector 7 in FIG.

Similar to the first embodiment, the infrared reflector 7 is formed into a wing shape substantially symmetrically. Further, the cut-off portion 9 of the infrared reflector 7 is provided across the left and right members of the wing-shaped left and right members around the center line (not shown) of each member. It is attached so that almost half of the infrared rays of
(B) The portion surrounded by the dotted line in the front view shows the position of the infrared detector 1.

As a result, infrared rays from substantially the front of the infrared detector pass through the cutout portion 9 of the infrared reflector 7 and directly enter the infrared detector 1, and infrared rays in the substantially lateral direction of the infrared detector are reflected. After being reflected by the device 7, it can be incident on the infrared detector 1.

(Embodiment 3) FIG. 5 is a sectional view showing another infrared detecting device according to the present invention. The cross section here is shown as a surface that extends to the left and right of the parabolic curved member. FIG. 6 is a perspective view (a) and a front view (b) showing an embodiment of the infrared reflector 7 in FIG.

As described with reference to FIG. 1, the infrared reflector 7 is provided between the condenser lens 3 and the infrared detector 1,
As shown in the perspective view of FIG. 6A, it is formed into a parabola-shaped curved surface substantially symmetrically. Also, the infrared reflector 7
The cutout portion 9 is provided across the left and right members of the wing-shaped left and right members around the center line (not shown) of each member. It is attached so that it can pass therethrough, and the portion surrounded by the dotted line in the front view of FIG. 6B is the portion showing the position of the infrared detector 1.

As a result, infrared rays from substantially the front of the infrared detector pass through the cutout portion 9 of the infrared reflector 7 and directly enter the infrared detector 1, and infrared rays in the substantially lateral direction of the infrared detector are reflected. The infrared rays can be incident on the infrared detector 1 while being reflected and collected by the parabolic curved surface of the container 7, the collection efficiency can be improved, and the detection distance can be further expanded.

Although not shown here, the shape of the infrared reflector 7 and the shape of the cutout portion 9 are not limited to the quadrangle, and any shape suitable for the shape of the infrared detector or the infrared detector 1 can be arbitrarily selected. It is a thing. Furthermore, the cut-off portion 9 of the infrared reflector 7 is within a range that does not hinder the incidence of infrared rays.
The size and arrangement of the two are not limited to one, and a plurality of them may be provided. It may also be regularly arranged in a grid pattern,
Alternatively, they may be provided irregularly.

[0032]

By providing the infrared reflector, the viewing angle, which is substantially limited by the opening area of the metal cap 5 of the infrared detector and the distance between the metal cap 5 and the detecting element 6, is greatly expanded to about 180 °. It becomes possible to do.

By making the condenser lens an assembly of a plurality of lenses, the focus and the incident direction of infrared rays can be adjusted, and the infrared rays can be surely made incident on the detection element.

If the right and left members of the infrared reflector are formed into parabolic curved surfaces, the light collection efficiency can be improved and the detection distance can be further extended.

[Brief description of drawings]

FIG. 1 is a sectional view showing an infrared detection device according to the present invention.

FIG. 2 is a diagram showing a detection range of an infrared detection device according to the present invention and a conventional example.

3 (a) is a perspective view and FIG. 3 (b) is a front view showing the infrared reflector in FIG.

4 (a) is a perspective view and FIG. 4 (b) is a front view showing another infrared reflector in FIG.

FIG. 5 is a sectional view showing another infrared detection device according to the present invention.

6 (a) is a perspective view and FIG. 6 (b) is a front view showing the infrared reflector in FIG.

FIG. 7 is a cross-sectional view showing a conventional infrared detection device.

[Explanation of symbols]

 1: Infrared detector 2: Printed circuit board 3: Condenser lens 4: Case 5: Metal cap 6: Detection element 7: Infrared reflector 8: Fixed part 9: Excision part 10: Reflection part

Claims (5)

[Claims] 1. An infrared detector comprising an infrared detector and a condenser lens, wherein the condenser lens is arranged in front of and outside the visual field of the infrared detector, and the condenser lens and the infrared detector are provided. A wing-shaped infrared reflector is provided between the infrared detector and the infrared detector, and the infrared reflector has a cutout portion in front of the visual field of the infrared detector. 2. The infrared detecting device according to claim 1, wherein the infrared detector comprises a pyroelectric type detecting element. 3. The condensing lens is composed of an assembly of a plurality of lenses, and the infrared rays condensed by the lenses in the field of view of the infrared detector are incident on the infrared detector through the ablation section, and the infrared detection is performed. The infrared detection device according to claim 1 or 2, wherein the infrared light collected by a lens outside the field of view of the container is arranged so as to be reflected by the infrared reflector and incident on the infrared detector. 4. The infrared ray according to any one of claims 1 to 3, wherein the infrared ray reflectors are arranged symmetrically with respect to the center of the infrared ray detector in a wing shape. Detection device. 5. The infrared reflector has parabola-shaped curved surfaces on each of the right and left sides.
Infrared detection device given in any 1 paragraph.