JPH03180729A - Pyroelectric type infrared detector - Google Patents

Abstract

PURPOSE:To detect a human body with high reliability without having the erroneous announcement by external factors by installing at least >=1 elements at both or one end of dual twin elements installed above and below. CONSTITUTION:The dual elements 1-a, 1-b are provided in one of the dual elements 3-a, 3-b and the dual elements 4-a, 4-b are disposed at one of the dual elements 2-a, 2-b. The output of the element 1 is obtd. and in succession the outputs of the elements 2 and 3 are simultaneously obtd. in this way when the human body moves in an arrow direction (from 1-a to 4-b). The output of the element 4 is finally obtd. There are no outputs of the elements 1, 3 and only the outputs of 2 and 4 are obtd. for the movement of a small animal and insect exclusive of the movement of the man and, therefore, such animal and insect are identifiable. Further, the signal processing to avoid recognizing as the moving body with respect to incoming light and an abrupt change in environmental temp. is possible unless the time difference of the outputs thereof is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an element pattern of an infrared detector.

[Prior art] Jiao t! ! :! Conventionally, infrared detectors are generally single type, dual type, and JP-A-58-2133.
A dual-twin type like the one seen in No. 96 is used, and the increased number of elements makes it possible to detect moving objects with high reliability. For example, in this type, in which a pair of dual elements 11-a and 11-b are placed below a pair of dual elements 10-a and 10-b in Fig. 3, in the case of a human body, both 10. However, in the case of small animals, the output of the IO element cannot be obtained and only 11 outputs can be obtained. The purpose is to distinguish between humans and small animals based on this difference.

However, the dual type and dual twin type can theoretically be used to prevent changes in the environment, sunlight, and cars! Although the design is designed to avoid false alarms due to the output cancellation of the opposing elements against external disturbance light such as dry lights, even if they are not moving, in reality there may be some strange misalignment of one or more of the parts inside the unit. There is some degree of element imbalance, and this causes output to be generated when the two dual elements work together in response to ambient light or environmental temperature changes. Although it is possible to distinguish this from the above-mentioned small animal, it results in false alarms.

From this perspective, it has been desired to develop a detector that does not generate false alarms due to factors other than human body detection.

[Means for solving the problem] In the detector of the present invention, elements of at least IX element or more are arranged at both ends or one side of the conventional dual twin type arranged above and below, and the output of each element is By signal-processing the output due to the time difference in an external circuit, various output patterns can be compared with any desired output pattern, and false alarms can be prevented.

[Effect] In other words, if an element is placed at both ends or one side of a dual twin type arranged above and below, when disturbance light acts on this element and each element of the dual twin, all output sources will output at almost the same time. It turns out. If this is patterned through signal processing, the circuit will be able to determine that it is not a moving object.

The same can be said for external factors such as sudden temperature changes in the environment and high-frequency external noise.

Of course, the dual twin type has a detection and judgment function based on the size of a small animal and a human body, so even if the object moves in the same way as a human body, the output pattern will differ depending on the size. This can also be easily distinguished from the human body through signal processing.

[Example] Next, embodiments of the present invention will be described using the drawings.

In Figure 1, one of the dual elements 3-a and 3-b is provided with the dual elements 1-a and 1-b, and one of the dual elements 2-a and 2-b is provided with the dual element 1-a and 1-b.
-a and 4-b dual elements were arranged. As a result, when the human body moves in the direction of the arrow in FIG. 1 (from 1-a to 4-b), the output of element 1 is obtained, and then the outputs of elements 2 and 3 are obtained simultaneously.

And M? , & the output of element 4 is obtained.

In addition to the movement of the human body, for the movement of small animals and insects, the outputs of elements 1 and 3 are not available, and only the outputs of elements 2 and 4 are obtained.
fully distinguishable. In addition, in response to sudden changes in ambient light or environmental temperature, even if each element obtains an output, signal processing is performed so that it will not be recognized as a moving object unless a temporal difference in the output is obtained. can.

In addition, by optically resolving the detection zone of each element to a high degree, the shape of a moving object that emits infrared rays can be obtained as a pattern output, making it possible to use it not only for human body detection but also for fire detection through pattern processing. is spreading. Similarly, as shown in FIG. 2, basically the same thing can be said when a dual element is installed next to a dual twin element consisting of upper and lower parts.

[5! As explained above, in a dual twin device that is installed above and below, by installing at least an element larger than an Ig element at both ends or on the - side, external factors that have been a problem in the past can be solved. Highly reliable human body detection without false alarms is now possible.

[Brief explanation of drawings]

1 and 2 are plan views of the light-receiving surface electrode of the element pattern of the infrared detector according to the present invention, and FIG. 3 is a plan view of the light-receiving surface electrode of the conventional dual-twin type element pattern. 3.9 Pyroelectric material], 2, 3, 4, 6, 7, 8, 9, 10, 11°: Dual elements a, b: One element of each dual element

Claims (1)

[Claims] A pyroelectric infrared detector characterized in that a dual twin element is arranged on a pyroelectric material that receives infrared rays and converts them into an electric signal, and at least one or more elements are arranged around the dual twin element.