JPH06194136A - Thermal image detecting device - Google Patents

Abstract

(57) [Summary] [Object] The present invention detects a two-dimensional image in a non-contact manner, and an infrared sensor 1 including a pyroelectric heat detection element group.
It is an object of the present invention to provide a system having a small size and a simple configuration using the. [Configuration] A two-dimensional thermal image can be detected with a small and simple structure by continuously or intermittently rotating the pyroelectric heat detection element group and the optical system which are arranged one-dimensionally on a straight line. Become. Further, by fixing the pyroelectric type heat detection element group arranged one-dimensionally on a straight line and moving or rotating the object to be measured, two-dimensional thermal image detection becomes possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal image detecting device for detecting a thermal environment and human body behavior.

[0002]

2. Description of the Related Art Conventionally, as a non-contact means for measuring temperature, there are a quantum infrared sensor and a thermal infrared sensor. The quantum infrared sensor has high sensitivity and fast response speed, but it requires cooling (-100 to
It is not suitable for consumer use. On the other hand, the thermal infrared sensor has a relatively low sensitivity, has a slow response speed, but does not require cooling, and thus has been put to practical use in the consumer market.

Among thermal infrared sensors, a pyroelectric infrared sensor utilizing the pyroelectric effect is often used. The pyroelectric infrared sensor has a differential output characteristic and produces an output only when the amount of incident infrared light changes. For example, when a person crosses in front of the pyroelectric infrared sensor, an output synchronized with it is generated. Although a human detection sensor utilizing this phenomenon has been put to practical use, it is not possible to obtain high-level information such as human behavior and human body temperature. There is also a point temperature sensor that uses a ceramic pyroelectric infrared sensor and a chopper, but its low sensitivity and slow response make it impossible to detect several tens of temperature data within 1 to 2 seconds. near.

Further, as a means for obtaining a two-dimensional thermal image, a method of arranging a pyroelectric infrared sensor in two dimensions has been considered.

[0005]

The method of arranging the pyroelectric infrared sensor in two dimensions is difficult to realize because the configuration of the sensor device and the system becomes complicated.

The present invention provides a system for obtaining a two-dimensional thermal image by using a one-dimensional pyroelectric infrared sensor array which is easy to realize.

[0007]

In order to solve the above-mentioned problems, the present invention provides a plurality of pyroelectric thermal detection element groups which are arranged one-dimensionally on a linear axis, and the pyroelectric thermal detection element group. A pyroelectric thermal detection element group is arranged, which has an integrated infrared transmissive lens and a chopper for limiting the amount of infrared rays incident on the pyroelectric thermal detection element group through the infrared transmissive lens. A two-dimensional image is obtained by having a rotation axis parallel to the linear axis or inclined by a certain angle, and rotating the pyroelectric thermal detection element group around the rotation axis.

Further, the present invention is to obtain a two-dimensional thermal image of a specific field of view by limiting the rotational movement of the pyroelectric heat detecting element group arranged on the linear axis to a reciprocating movement by limiting it to a fixed angle.

Further, the present invention obtains a two-dimensional thermal image by performing thermal image detection only when reciprocating motion is rotating in a fixed direction.

Further, the present invention is to obtain a two-dimensional thermal image by performing thermal image detection in both directions of reciprocating motion.

Further, according to the present invention, the object to be detected is moved two-dimensionally by moving the object to be detected on an axis which is perpendicular to the linear axis on which the pyroelectric heat detecting element group is arranged or parallel to a straight line inclined by a certain angle. To get an image.

Further, according to the present invention, a two-dimensional image is obtained by rotating the object to be detected about a rotation axis which is parallel to the linear axis on which the pyroelectric heat detection element group is arranged or which is inclined by a constant angle. Is what you get.

Further, the present invention is to obtain a two-dimensional thermal image by continuously performing thermal image detection. Further, the present invention obtains a two-dimensional thermal image by intermittently performing thermal image detection.

Further, in the present invention, a pyroelectric thin film is used for the pyroelectric type heat detecting element group to achieve miniaturization, high sensitivity and high speed of the element group.

[0015]

The present invention is a two-dimensional thermal image having a small size and a simple structure, which is obtained by continuously or intermittently rotating the pyroelectric type heat detecting element group and the optical system which are one-dimensionally arranged on a straight line. A detection system is provided.

Further, the present invention provides a system for obtaining a two-dimensional thermal image by fixing a pyroelectric type heat detecting element group which is one-dimensionally arranged on a straight line and moving or rotating an object to be detected.

[0017]

Embodiments of the present invention will be described with reference to FIGS. 1 to 5.

FIG. 1 is a diagram showing a first embodiment of the present invention. In the figure, reference numeral 1 denotes an infrared sensor composed of a pyroelectric thermal image detecting element group. For example, five pyroelectric thermal detecting elements are arranged on a straight line as shown by 1a to 1e in FIG.
Each element is responsible for one of the five vertical viewing angles. Reference numeral 2 is an infrared transmission lens arranged so as to connect a thermal image to each pyroelectric heat detection element, and the infrared transmission lens is arranged so that the optical axis passes through the center of a plurality of pyroelectric heat detection element groups. The infrared sensor 2 and the infrared sensor 1 are integrated. Three
Is a chopper that does not transmit infrared rays. 5 is a chopper 3
It is a band amplification unit that band-amplifies a minute voltage output from the infrared sensor 1 in accordance with the opening / closing operation of, and is provided corresponding to each pyroelectric heat detection element. Reference numeral 6 is a detection object which is a subject of the infrared sensor.

A mechanism for obtaining a two-dimensional thermal image from the pyroelectric thermal detection element group arranged in a straight line as shown in FIG. 2 will be described with reference to FIGS.

FIG. 3 corresponds to the thermal image detecting device according to the first to fourth aspects of the present invention. While rotating the infrared sensor 1 with respect to the object 6 to be detected with reference to a rotating shaft as shown in FIG. 3a. It is shown that the two-dimensional thermal image developed in the horizontal direction as shown in FIG. 3b is obtained by detecting the thermal image. The viewing angle of the infrared sensor 1 is narrowly limited in the horizontal direction, and a thermal image having a certain limited horizontal viewing angle is detected in synchronization with the opening and closing of the chopper 3 whose cycle and duty are controlled. The detected one-dimensional thermal image is detected in time series corresponding to opening and closing of the chopper 3, and becomes a two-dimensional thermal image. The infrared sensor 1 can be rotated in only the same direction depending on the purpose, size of the detection object, movement range, or the like, or can be reciprocally rotated only in a fixed angle range. When it is necessary to detect the temperature or position to be detected with higher accuracy in the infrared sensor 1 that reciprocally rotates only within a certain angle range, the detection operation can be performed by both reciprocating rotation. However, in other cases, the detection operation can be performed only in one of the reciprocating rotations.

These methods are effective for detecting the heat distribution in a certain space and the behavior of a person.

FIG. 4 corresponds to a thermal image detecting device according to a fifth aspect of the present invention. The infrared sensor 1 moves the detection object 6 on a certain axis as shown in FIG.
It shows that a two-dimensional thermal image developed in the horizontal direction such as b is obtained. The viewing angle of the infrared sensor is narrowly restricted in the horizontal direction, and a thermal image with a limited horizontal viewing angle is detected in synchronization with the opening and closing of the chopper 3 whose cycle and duty are controlled. The detected one-dimensional thermal image is detected in time series corresponding to opening and closing of the chopper 3, and becomes a two-dimensional thermal image. This method is effective when detecting the shape and heat distribution of an object placed at a specific position, or when detecting the behavior of a person or object moving in a certain space.

FIG. 5 corresponds to a thermal image detecting device according to a sixth aspect of the present invention. The infrared sensor 1 rotates the object 6 to be detected about an axis as shown in FIG. It is shown that a two-dimensional thermal image horizontally developed is obtained. Further, the viewing angle of the infrared sensor is narrowly limited in the horizontal direction, and a thermal image having a limited horizontal viewing angle is detected. The detected one-dimensional thermal image is detected in time series corresponding to opening and closing of the chopper 3, and becomes a two-dimensional thermal image. This method is effective for detecting the shape and heat distribution of an object placed at a specific position.

As described above, a method of forming a two-dimensional image can be selected depending on the purpose of the infrared sensor, the size of the detection target, the moving range, and the like.

Further, the commonly used pyroelectric infrared sensor is a so-called bulk type which uses a sintered body of a pyroelectric thick film, but this bulk type has a problem that the thermal time constant cannot be made small and the response is slow. Have a point Therefore, by using a pyroelectric heat detecting element using a pyroelectric thin film made of PbTiO ₃ or the like, the response time can be made about 1/10 of that of the bulk type. By using the pyroelectric heat detection element using this pyroelectric thin film and shortening the response time, the behavior of the human body can be accurately detected. Further, if the pyroelectric thin film is used, the device can be further downsized.

[0026]

According to the present invention, a two-dimensional thermal image can be detected with a small and simple structure by rotating the one-dimensionally arranged pyroelectric heat detecting element group.

Further, a two-dimensional thermal image can be detected with a small and simple structure by moving or rotating the object to be detected with respect to the pyroelectric heat detecting element group arranged in one dimension.

Further, a highly accurate two-dimensional thermal image can be detected by selecting from the above methods a method of constructing a two-dimensional thermal image from the purpose of the infrared sensor, the size of the detection object, the moving range, etc. Is possible.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a configuration diagram of an infrared sensor according to the same embodiment.

FIG. 3A is an explanatory diagram of a mechanism for obtaining a thermal image. FIG. 3B is an explanatory diagram of a mechanism for obtaining the thermal image.

FIG. 4A is an explanatory diagram of a mechanism for obtaining a thermal image. FIG. 4B is an explanatory diagram of a mechanism for obtaining the thermal image.

FIG. 5A is an explanatory diagram of a mechanism for obtaining a thermal image. FIG. 5B is an explanatory diagram of a mechanism for obtaining the thermal image.

[Explanation of symbols]

 1 Pyroelectric heat detection element group 2 Infrared transmission lens 3 Chopper 5 Band amplification section 6 Measurement target

[Procedure amendment]

[Submission date] November 26, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a configuration diagram of an infrared sensor according to the same embodiment.

FIG. 3A is an explanatory diagram of a mechanism for obtaining a thermal image. FIG. 3B is an explanatory diagram of a mechanism for obtaining the thermal image.

FIG. 4 is an explanatory diagram of a mechanism for obtaining a thermal image.

FIG. 5 is an explanatory diagram of a mechanism for obtaining a thermal image.

[Explanation of symbols] 1 pyroelectric heat detection element group 2 infrared transmission lens 3 chopper 5 band amplification section 6 measurement object

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuto Mukai 1006 Kadoma, Kadoma-shi, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (9)

[Claims] 1. A plurality of pyroelectric heat detecting element groups arranged one-dimensionally on a linear axis, an infrared transmitting lens integrated with the pyroelectric heat detecting element group, and the infrared transmitting lens. A chopper for limiting the amount of infrared rays incident on the pyroelectric heat detecting element group through the, and rotation parallel to the linear axis where the pyroelectric heat detecting element group is arranged, or inclined by a certain angle. A thermal image detecting device having an axis and rotating the pyroelectric thermal detection element group about the rotation axis to obtain a two-dimensional image. 2. The thermal image detection device according to claim 1, wherein the rotational movement is limited to a certain angle and reciprocated. 3. The thermal image detecting device according to claim 1, wherein the thermal image detection is performed only when the reciprocating operation is rotating in a fixed direction. 4. The thermal image detection device according to claim 2, wherein thermal image detection is performed in both directions of the reciprocating operation. 5. A plurality of pyroelectric heat detecting element groups arranged one-dimensionally on a linear axis, an infrared transmitting lens integrated with the pyroelectric heat detecting element group, and the infrared transmitting lens. Having a chopper for limiting the amount of infrared rays incident on the pyroelectric heat detecting element group through, and a straight line perpendicular to the linear axis where the pyroelectric heat detecting element group is arranged, or inclined by a certain angle A thermal image detecting device that obtains a two-dimensional image by moving an object to be detected on an axis parallel to the axis. 6. A plurality of pyroelectric heat detecting element groups arranged one-dimensionally on a linear axis, an infrared transmissive lens integrated with the pyroelectric heat detecting element group, and the infrared transmissive lens. A chopper for limiting the amount of infrared rays incident on the pyroelectric heat detecting element group through the, and rotation parallel to the linear axis where the pyroelectric heat detecting element group is arranged, or inclined by a certain angle. A thermal image detecting device that obtains a two-dimensional image by rotating an object to be detected around an axis. 7. The thermal image detection device according to claim 1, wherein the thermal image detection is performed continuously. 8. The thermal image detection device according to claim 1, wherein the thermal image detection is performed intermittently. 9. The thermal image detecting device according to claim 1, wherein a pyroelectric thin film is used for the pyroelectric thermal detection element group.