JP2010262422A - Infrared abnormality detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an infrared abnormality detection device performing high-reliability monitoring at low cost, performing only simple subtraction processing, and not needing a complicated processing unit. <P>SOLUTION: The infrared abnormality detection device includes a multi-element infrared detection element array arranged in two dimensions, and includes both a storage device storing infrared output read from each element updated at a certain interval as background data while not deciding abnormality and an arithmetic device subtracting the background data stored in a memory from occasionally-output output from the infrared detection array, and outputs a result obtained by performing the subtraction as difference data. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a detection device that uses infrared rays, and relates to an infrared abnormality detection device that can reliably detect an abnormality with a low-cost device in a minimum necessary system.

  For example, a pyroelectric infrared sensor is used as an abnormality detection device for detecting an abnormality of an intruder or the like using conventional infrared rays, and when an abnormality occurs in the monitoring area, the generated thermal change is detected by the pyroelectric infrared sensor. Anomaly detection devices are widely used in the market.

  For the purpose of increasing the reliability, as disclosed in Japanese Patent Application Laid-Open No. 2000-76521, a human who emits infrared rays with a pyroelectric infrared sensor as an abnormality detection device using a pyroelectric infrared sensor and an optical camera in combination. 2. Description of the Related Art An anomaly detection device is known that records a video by operating a visible camera when an anomaly such as an intruder is detected.

Further, there is also known an abnormality detection device that monitors a thermal image in a monitoring area using an infrared camera as disclosed in JP-A-10-336630.
Further, as disclosed in Japanese Patent Laid-Open No. 7-37064, an abnormality in which an abnormality is determined by calculating a difference between two images input with a time difference from a surveillance camera and performing image processing on the difference image. There is a detection device.

JP 2000-76521 JP-A-10-336630 JP-A-7-37064

  Regardless of whether it is visible or infrared, using any conventional technology, it is necessary to perform complex arithmetic processing on the image data from the camera in real time. A processing device was required and the device was very expensive. In addition, in order to monitor a wide range, there is a problem that it is necessary to construct a monitoring system in which many devices are installed, which is more costly.

  The present invention has been made to solve the above-described problems, and the apparatus itself does not need a complicated arithmetic processing apparatus only by a simple subtraction process, and can perform low-cost and highly reliable monitoring. An object of the present invention is to provide an infrared abnormality detection device that can be used.

  The abnormality detection device according to the invention of claim 1 has a multi-element infrared detection element array arranged two-dimensionally, and outputs infrared output read from each element updated at a certain interval while it is not judged as abnormal. It has a storage device that stores it as background data, and an arithmetic device that subtracts the background data stored in the memory from the output from the infrared detection array that is output as needed, and outputs the result of the subtraction as difference data for subtraction. When the result exceeds the set threshold, an abnormality is detected and an abnormality signal is generated.

  In the infrared abnormality detection apparatus according to the invention of claim 2, the interval at which the output of the infrared detection array is read for updating the background data can be varied depending on the object for detecting the abnormality.

  In the infrared abnormality detection apparatus according to the invention of claim 3, when an abnormality is detected, the entire surface of the sensor element is masked with a shutter, stored as background data, and then the shutter is opened, and the output of the infrared sensor element is read at any time. By subtracting background data from the output of the array, an infrared image at the time of abnormality can be obtained.

  According to the first aspect of the present invention, since the background data when it is not determined to be abnormal is stored and subtracted from the infrared output that is read as needed, if there is no change in the infrared rays generated in the monitoring area, the differential output data is Only 0 is output. However, when a person who emits infrared rays such as a human body enters the monitoring area, or when a fire or the like occurs in the monitoring area, a large difference occurs in the infrared signal, and the difference data is output. When the threshold value is exceeded, an abnormality is detected and an abnormality detection signal is output, so that an inexpensive abnormality detection device can be configured with only an infrared detection element array and a simple arithmetic processing device.

  According to the invention of claim 2, the timing of reading as background data at any time in the normal state depends on the object to be detected and the conditions of the background, for example, when detecting a gradual temperature change abnormality, the error is reported by increasing the interval. When detecting an abnormality such as an intruder, the false interval due to a gradual change in the background temperature can be prevented by shortening the interval.

  According to the invention of claim 3, when the abnormality is detected, the shutter is closed, the output data from the infrared detection element array is read as background data, and the subtraction is performed from the output data from the infrared detection element array after the shutter is opened. Since the temperature distribution on the shutter surface is constant and there is no temperature difference, the subtracted value is a detailed infrared image including a background image representing the temperature difference in the monitoring area. By performing image processing on the image data, a more reliable system can be constructed.

The figure which shows schematic structure of the infrared rays abnormality detection apparatus concerning this invention. The output data from the differential data output unit at the time of warning is an image. The output data from the differential data output unit at the time of abnormality detection is imaged. This is an image of the detailed output data from the differential data output unit when an abnormality is detected.

  Embodiment 1 Hereinafter, Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram of an infrared abnormality detection apparatus according to an embodiment of the present invention. In FIG. 1, a two-dimensional infrared detection element array 10 for detecting infrared rays, a memory 11 for storing background data read from the infrared detection element array 10, and a value stored from the output from the infrared detection element array read at any time are subtracted. An arithmetic processing unit 12 for determining whether or not the threshold value is exceeded, and as a result, an abnormality detection output unit 13 for outputting an abnormality detection signal when the set threshold value is exceeded, a difference data output unit 14 for background data, an infrared detection element The infrared anomaly detection apparatus has a shutter and a control unit 15 for masking the entire surface of the array 10.

  Next, an embodiment of the infrared abnormality detection device of the present invention will be described. First, when an abnormality monitoring command is input to the infrared abnormality detection device of the present invention, each output from the infrared detection element array 10 is read and stored in the memory 11 as background data. Next, the stored data corresponding to each infrared element array is subtracted from each output of the infrared detection element array 10 read as needed, and the difference data is output from the image output unit 14. If it is immediately after the abnormality monitoring command is input, the subtraction result is 0, and the difference data output from the image output unit 14 is also 0. FIG. 2 is an image of the difference data, but nothing is displayed because the difference is zero. After that, if there is a change in the infrared rays generated by intruders, fires, etc. in the monitoring area, the subtraction result of the human body in the infrared detection element array and the part where the fire was detected does not become zero and a difference occurs. To do. When this difference exceeds the threshold set in the arithmetic processing unit 12, it is determined that there is an abnormality, and the abnormality detection output unit 13 outputs an abnormality signal, and at the same time, the difference data output unit output unit 14 outputs difference data. FIG. 3 is an image of the difference data at this time, but only the detected human body is displayed as the difference.

  However, as time passes after the monitoring command is input, the background data initially stored in the memory 12 and the infrared ray obtained at any time, even if not abnormal, due to the temperature change in the monitoring area and the temperature drift of the infrared detection element array 10. A difference occurs in each output data of the sensing element array 10, and the result of subtraction by the arithmetic processing unit 12 does not become zero. If the difference caused by the change in the background temperature exceeds the threshold value, false detection is performed. Therefore, it is necessary to update the background data stored in the memory 11 at any time while the difference does not exceed the threshold value and is not determined to be abnormal. Yes, the update interval at this time is determined by the detection target. For example, when an intruder is detected as abnormal, the update interval should be within a few seconds, so even if the background temperature changes during this period due to environmental changes, it can be updated within a slight change in background temperature. As a result, there is no false detection. In addition, when detecting an abnormality such as a fire, it is assumed that the temperature gradually increases, and it is necessary to set the update interval to several minutes or more, which overlaps with the environmental temperature change in time. However, since the target infrared energy is in the range of several tens of degrees at the environmental temperature and several hundred degrees in the case of fire, the threshold range can be set large. There is no.

  As described above, the infrared abnormality detection device of the present invention can be monitored by itself, and dozens of infrared abnormality detection devices and infrared image data output from the infrared abnormality detection device at the time of abnormality detection, image processing, advanced determination By constructing a network with one arithmetic processing unit capable of performing the above, it becomes possible to construct a cheaper and more reliable monitoring system.

DESCRIPTION OF SYMBOLS 10 Infrared detector element array 11 Memory | storage memory 12 Operation processing part 13 Detection signal output part 14 Differential data output part 15 Shutter and control part

Claims (3)

  Has a multi-element infrared detector array arranged in two dimensions, and has a memory to store infrared output read from the infrared detector array at a certain interval as background data while it is not judged abnormal, and after storage It has an arithmetic unit that subtracts the memory data from the output from the infrared detector element array that is read, outputs the subtracted data, detects an abnormality when the subtraction result exceeds the set threshold, and outputs an abnormal signal. An infrared anomaly detector characterized by being generated.   An infrared anomaly detector characterized in that the interval at which the output of the infrared detecting element array for updating the background data is read is variable depending on the object for detecting the anomaly.   When an abnormality is detected, the entire surface of the infrared detector array is masked with a shutter with a constant surface temperature, and the output of the infrared detector array is stored when subtracted from the infrared output that is read from time to time after the shutter is opened. Is output as differential data.