JP5864335B2 - Human body detection device - Google Patents

Description

  The present invention includes a plurality of pyroelectric elements that receive infrared rays from a detection area formed in a monitoring zone, which is a target area for detecting a human body, and an amount of infrared energy that varies depending on a moving object that has entered the monitoring zone. The present invention relates to a human body detection device that detects the presence or absence of a human body based on the detection of.

  Conventionally, in various places such as commercial buildings, public facilities, apartment buildings, etc., human body detection using infrared rays radiated from an object to detect that a moving object such as a human body has entered a specific surveillance zone. A device is provided.

  This human body detection apparatus generally includes a pyroelectric element as infrared detection means (sensor). A pyroelectric element is an element that uses a pyroelectric effect in which spontaneous polarization in a ferroelectric material (for example, PZT) changes according to a temperature change, and by detecting a voltage induced by this pyroelectric effect. An intrusion of a human body into the monitoring zone can be detected as a temperature change.

  In such a human body detection device, in order to determine the presence or absence of a human body in accordance with the amount of change in infrared energy in the monitoring zone, infrared rays from a plurality of detection areas formed in the monitoring zone are collected by the infrared ray detection means by the light collecting means. There is a case where a configuration of condensing light on the (sensor) is employed. However, in the case where a plurality of detection areas are formed in the monitoring zone by the light collecting means, the area of the detection area set on the near side as viewed from the sensor is as viewed from the sensor. Compared with the area of the detection area set far away, it becomes relatively small. For this reason, when an object of the same size passes through a distant detection area, the amount of change in infrared detected by the infrared detecting means and the infrared detected by the infrared detecting means when passing through the preceding detection area In comparison with the amount of change, the amount of change in infrared rays in the detection area in front is larger. Therefore, the detection area set in front of the sensor has a higher sensitivity to detect the human body than the detection area set far away, and small animals such as cats and rabbits tend to be erroneously determined as human bodies. There is a problem that it is expensive.

  In such a human body detection device, as a prior art for preventing a small animal from being erroneously determined as a human body, for example, a detection device as in Patent Document 1 is known. According to the invention of the detection apparatus described in Patent Document 1, a plurality of types of filters having different infrared transmission amounts can be selectively disposed between the light collecting means and the pyroelectric element. Change the distance from the set monitoring zone to the detection device by switching to a filter that transmits less infrared light and adjusting the amount of infrared light that reaches the sensor as the distance from the sensor to the monitoring zone is set shorter. Appropriate detection sensitivity can be set according to the

Japanese Patent No. 3489915

However, such conventional techniques have the following problems.
The detection device of Patent Document 1 is suitable for changing the setting of the entire monitoring zone and adjusting the overall detection sensitivity of the monitoring zone, but when a plurality of detection areas are formed in the monitoring zone, It is technically difficult to adjust the detection sensitivity in each detection area individually. In other words, it is necessary to precisely design the light condensing means and the filter in accordance with a plurality of detection areas, and depending on the number and arrangement of the detection areas, a small animal is erroneously determined as a human body in the detection area in front of the sensor. In some cases, it is difficult to design the light collecting means and the filter to such an extent that they can be appropriately prevented.

  Therefore, the present invention has been made in view of the above problems, and when a plurality of detection areas are formed in the monitoring zone by the light collecting means, an error caused by a small animal in the range on the front side relative to the sensor. An object of the present invention is to provide a human body detection device that can appropriately prevent detection.

In order to achieve the above object, a human body detection device according to claim 1 of the present invention provides:
A plurality of infrared detecting means for individually detecting infrared rays and outputting signals;
A condensing unit that forms a plurality of detection areas in a monitoring zone set on a monitoring plane as a region for detecting a human body, and that condenses infrared rays emitted from the detection areas on the corresponding infrared detection units; ,
Area determination means for determining the presence or absence of a change in infrared for each of the detection areas based on a signal output from each infrared detection means;
A human body determination means for determining that a human body has been detected and outputting a human body determination signal when the detection area determined by the area determination means has changed to a predetermined number of areas of at least 3 or more;
A human body detection device comprising:
When the condensing means is within a short distance range that is a predetermined distance away from a position directly below the human body detection device in the monitoring zone, the number of detection areas equal to or greater than the predetermined number of areas is not arranged in series adjacent to each other. Thus, the detection area is formed as described above.

The human body detection device according to claim 2 is the human body detection device according to claim 1,
In the far distance range, which is the range excluding the near distance range in the monitoring zone, the light collecting means are adjacent to each other in a direction in which the number of the detection areas equal to or greater than the predetermined number of areas is away from the direct position. The detection areas are formed so as to be arranged in series.

  The detection area formed in the monitoring zone by the light collecting means for guiding infrared rays to the sensor is smaller in the detection area formed in front than the detection area formed in the distance. Then, it is easy to generate a false alarm by detecting a change in infrared rays by a small animal larger than a relatively far detection area. In order to solve this problem by a simple and effective configuration, the present invention tends to move linearly when observing small animal behavior characteristics, that is, small animals moving around in a limited narrow range. It was created by paying attention to the characteristic that it is rare to change the position of the movement.

Therefore, according to the human body detection device described in claim 1, a number of detection areas equal to or greater than the predetermined number of areas are adjacent to each other within a short distance range that is a predetermined distance away from a position directly below the human body detection device in the monitoring zone. The detection area was formed so that they were not lined up in series. In other words, in a short distance range from the front of the monitoring zone to the far direction, adjacent detection areas do not line up in series with a predetermined area number or more that is a reference for determining a human body. The possibility of false detection of small animals that tend to move around has decreased, and it has been possible to prevent false alarms by small animals in the area close to the human body detection device in the monitoring zone.
Even if the detection area is formed so that adjacent detection areas are not arranged in series within the short distance range, the human body moves between adjacent detection areas because the size of the human body is larger than the size of the small animal. Will be. For this reason, it is possible to detect a human body.

In addition, if the angles formed by the respective directions from the human body detection device to the adjacent detection areas are fixed, the distance between the adjacent detection areas becomes larger in the distance from the monitoring zone than in the short distance range.
For this reason, if the detection area is not serially located in the distance from the monitoring zone, even if a human body actually intrudes, there is a possibility that changes in infrared rays cannot be determined in the detection area that exceeds the predetermined number of areas, which is the reference for determining the human body Becomes higher.

Therefore, according to the human body detection device described in claim 2, unlike the case of claim 1, in the distance from the monitoring zone, the criterion for determining the human body in the direction away from the position immediately below the human body detection device in the monitoring zone. By making the adjacent detection areas line up in series for a predetermined number of areas or more, it was possible to prevent false alarms.
It should be noted that the area of the detection area is farther away than the detection area in the short distance range. For this reason, even if detection areas adjacent in the distance are arranged in series, a small animal smaller than the human body is not detected.

It is a schematic block diagram which shows the system configuration | structure of the human body detection apparatus which concerns on embodiment of this invention. It is a schematic perspective view when the apparatus is installed on the ceiling. It is explanatory drawing which shows concepts, such as a monitoring zone in the same apparatus, a detection zone, and a detection area. It is explanatory drawing which shows the detection method of the human body by the dual element type pyroelectric element which the same apparatus has with (a)-(e). It is explanatory drawing which shows the example of arrangement | positioning of the detection area and detection zone which were formed in the monitoring zone in this embodiment. It is an enlarged explanatory view showing an example of formation of detection areas and detection zones formed within a short distance range of a monitoring zone in the present embodiment. It is explanatory drawing which shows the example of formation of the detection area formed in the monitoring zone in this embodiment, a part (a) shows the example which three detection areas are not in series, and part (b) shows three An example in which the detection areas are in series is shown. It is explanatory drawing which shows the processing content of the object detection by the dual element pyroelectric element single-piece | unit of this embodiment. It is a timing chart for demonstrating the human body determination process in this embodiment.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the present invention is not limited by this embodiment, and all other forms, examples, operation techniques, etc. that can be implemented by those skilled in the art based on this form are included in the scope of the present invention. .

[Device configuration]
<About formation and basic configuration in the monitoring zone>
First, the human body detection device 1 according to the present embodiment will be described with reference to FIGS.
As shown in FIG. 3, the human body detection device 1 shown in FIG. 1 to FIG. 3 covers the entire monitoring zone (set on the floor in the building) to be monitored as an area for detecting a human body. In order to monitor evenly, for example, it is installed above the wall of the building or on the ceiling, and as shown in FIG. 1 to FIG. 2, infrared detection means 11, condensing means 12, signal processing means 13, control means 14, The output unit 15 is schematically configured. The human body detection device 1 includes these configurations inside a housing in which a cover that transmits infrared rays from the monitoring zone and a pedestal for fixing to a wall or ceiling are combined. In FIG. 2, this casing is omitted.

  In this embodiment, as shown in FIG. 3, for a monitoring zone virtually set on a monitoring plane (including a substantially horizontal plane or an uneven surface) such as a floor surface in a building or a ground surface outside the building, for example. The two-dimensional monitoring area corresponding to each of the pyroelectric elements that are radially formed as seen from the human body detection device 1 is referred to as a “detection area”, and the first pyroelectric element 11a or the second pyroelectric element 11b is A combination or group of detection areas to be formed is referred to as a “detection zone”, and a condensing region of infrared light that is condensed while converging from each detection area toward the corresponding pyroelectric element (in the figure, a substantially pyramid shape) ) Is referred to as a “light collection space”. In the example of FIG. 3, the “detection zone” is illustrated as an example, and therefore, the “detection zone” and the monitoring zone are illustrated to have substantially the same position and size. When a plurality of “detection zones” are formed, a monitoring zone is set as an area surrounding the plurality of “detection zones”. The monitoring zone is appropriately set by a person who installs the human body detection device 1 using an adjustment mechanism that changes the direction of the light collecting means 12 provided inside the housing.

  In this embodiment, when a moving object that has entered the monitoring zone is detected to have crossed a plurality of detection areas, the moving object is determined. The number of the detection areas straddled is set appropriately in advance for the storage means (not shown) of the human body detection device 1. Specifically, a predetermined number of areas (for example, three) is set in advance as the number of human body determination areas as a reference for determining that a moving object detected to straddle a plurality of detection areas is a human body. A moving object detected over the number of human body determination areas is identified as “human body”, and a moving object detected with less than the number of human body determination areas is identified as “small animals (dogs, cats, rabbits, etc.)”. . The number of human body determination areas can be arbitrarily set to increase or decrease according to the installation environment of the human body detection device 1 or the like.

<About infrared detection means>
As shown in FIG. 1, the infrared detection means 11 included in the human body detection device 1 includes a first pyroelectric element 11 a which is a dual twin pyroelectric element including two dual element pyroelectric elements a 1 and a 2, and a dual element. The second pyroelectric element 11b which is a dual twin type pyroelectric element including the pyroelectric elements b1 and b2.

  The dual element type pyroelectric element prevents false detections due to changes in background temperature in the area caused by shadows and strong winds in the monitoring zone to be monitored, external radio noise or ambient light such as sunlight. Therefore, a + polar element and a −polar element having different polarities arranged in parallel in the horizontal direction are provided, and a + polar area (E +) due to the + polar element and a −polarity due to the −polarity are provided in the monitoring zone. The detection area having the area (E−) is formed.

FIG. 4 shows a human body detection method using a dual element type pyroelectric element.
FIG. 4A schematically shows a detection area formed in the monitoring zone. As indicated by an arrow in the figure, for example, a moving object moves from the detection area (E1 +) to the detection area (E1-). The case where it moved to is shown. In this case, as shown in FIG. 4B, when the moving object first enters the detection area (E1 +), the amount of infrared energy in the detection area (E1 +) changes. The + output of the pyroelectric element corresponding to the detection area (E1 +) where the moving object has entered is output to the + side. Next, when the moving object moves from the detection area (E1 +) to the detection area (E1-), as shown in FIG. 4C, the moving object has entered the detection area (E1-). The amount of infrared energy in (E1-) changes. Since the pyroelectric element corresponding to the detection area (E1-) has the opposite polarity to the element corresponding to the detection area (E1 +), the -output is output to the-side. When the moving object leaves the detection area (E1-), the waveform in FIG. 4C gradually returns to before the change. As will be described later in <Signal processing means>, the + or − output pyroelectric element output outputted by each of the dual element pyroelectric elements is like a “composite output” shown in FIG. And output to the control means 14 at the subsequent stage.

  Note that when the moving object is kept stopped in each detection area, no waveform is output because there is no change in infrared energy. Infrared energy changes such as ambient light and background temperature cancel each other and cancel out each other, so that almost no output is generated from the pyroelectric element, for example, “background temperature change” shown in FIG.

<Signal processing means>
As shown in FIG. 1, the dual element pyroelectric elements a1 and a2 include first and second elements that perform predetermined signal processing, which will be described later, on pyroelectric element outputs indicating the amount of infrared energy change received by these elements. Two-signal processing means 13a and 13b are connected to each other. Further, the dual element pyroelectric elements b1 and b2 include third and fourth signal processing means 13c for performing predetermined signal processing, which will be described later, on the pyroelectric element output indicating the amount of infrared energy change received by each of these elements. , 13d are connected to each other.

  The signal processing means 13a, 13b, 13c, 13d are pyroelectric element outputs indicating the energy change amounts of the received infrared rays output from the dual element pyroelectric elements a1, a2, b1, b2, that is, the detection area (described above). 4+ (FIG. 4 (b)) of the element corresponding to E1 +) and −output (FIG. 4 (c)) corresponding to the detection area (E1-) are combined and amplified to obtain FIG. 4 (d). As shown in FIG. 4, the detection signal for each element corresponding to the change in the synthesized infrared energy amount is output to the control means 14 at the subsequent stage. The signal amplification factors in the signal processing units 13a to 13d are all set to be the same.

  Details of the control will be described in detail in <Regarding Control Unit> below, but the detection signals from the signal processing units 13a to 13d are given to the corresponding area determination units 14a of the control unit 14 to determine each area. The means 14a outputs an object detection signal when it is determined that the detection signal sent from each of the signal processing means 13a to 13d exceeds a predetermined threshold value. When the human body determination unit 14b of the control unit 14 determines that a moving object has been detected across a predetermined number of detection areas (three in this example), the detected movement The object is determined as a “human body”.

<About the arrangement of detection areas formed by the light collecting means>
As shown in FIGS. 1 and 2, the condensing means 12 (12a, 12b) is composed of various optical systems that collect infrared rays, such as a multi-segment lens and a condensing mirror, and the first and second pyroelectric elements. It is provided for each of the elements 11a and 11b. In the monitoring zone, the condensing means 12 transmits infrared rays from a plurality of detection areas formed radially around the apparatus so as to correspond to the plurality of dual element pyroelectric elements to the corresponding dual element pyroelectric elements. Condensed. Further, as shown in FIG. 2, the condensing means 12 includes a first pyroelectric element condensing region and a second pyroelectric element condensing area for condensing each element by limiting the optical path of the condensed infrared light. A shielding member 12c for providing an optical region is provided.

  FIG. 5 is an example of the arrangement of detection areas formed in the monitoring zone by the light collecting means 12. As shown in FIG. 5, in the present embodiment, the detection areas a1 and a2 formed by the first pyroelectric element 11a and the second pyroelectric element are formed in a monitoring zone having a shape generally recognized as a fan shape in plan view. A plurality of detection areas b1 and b2 formed by 11b are formed radially with the human body detection device 1 as the center. The plurality of detection areas a1 and a2 formed by the first pyroelectric element 11a are collectively referred to as a detection zone A, and the plurality of detection areas b1 and b2 formed by the second pyroelectric element 11b are collectively referred to as a detection zone. Called B.

  As shown in FIG. 5, the arrangement of the detection areas a1, a2, b1, b2 formed by the first pyroelectric element 11a and the second pyroelectric element 11b, which are two pyroelectric elements, is the detection of the human body in the monitoring zone. There is a difference between the inside of a short distance range N that is a predetermined distance d away from the position O directly below the apparatus and the inside of a long distance range F that is a range excluding the short distance range N in the monitoring zone.

  The predetermined distance d from the position O immediately below the boundary between the short distance range N and the long distance range F depends on the sensitivity of the pyroelectric element, the entire monitoring zone, the height of the human body detection device, the monitoring purpose, and other conditions. However, for example, as an example, the distance can be set to a distance of about 2 to 3 m from the directly below position O, which is a distance with less detection error of human body determination.

  First, as shown in FIG. 5 showing the entire monitoring zone and FIG. 6 in which the short-distance range N in the monitoring zone is enlarged, within the short-distance range N, the predetermined number of areas (the number of human body determination areas described above) In the example, the detection areas are formed so that 3) or more detection areas are not arranged next to each other in series.

  Here, the series means a direction of a straight line connecting the centers of gravity of at least two of the detection areas A1 when assuming a plurality of adjacent detection areas A1 to A3 as shown in the respective drawings of FIG. doing. Therefore, in this example, as shown in FIG. 7A, the center G3 of the third detection area A3 does not exist on the straight line passing through the centers G1 and G2 of the two detection areas A1 and A2. In this case, the three detection areas A1 to A3 are not arranged in series. Further, as shown in FIG. 7B, when there is one straight line passing through the gravity centers G1 to G3 of the three detection areas A1 to A3, the three detection areas A1 to A3 are connected in series. It will be in line.

  As shown in FIG. 6, within the short distance range N, a set of two detection areas b1 and b2, a set of two detection areas a1 and a2, and 2 A set of detection areas b1 and b2 and a set of two detection areas a1 and a2 are arranged in a staggered manner for each set, and three or more detection areas that are the number of human body determination areas are adjacent to each other. Detection area is formed so as not to line up in series

The area of the detection area formed in the monitoring zone by the light collecting means for guiding the infrared rays to the sensor is smaller in the detection area in front than the detection area in the distance. In particular, it is easy to generate a false alarm by detecting a change in infrared rays by a small animal more than the far distance range F, but according to the human body detection device of this embodiment, within the near distance range N of the monitoring zone, Since the number of human body judgment areas is not more than 3 in series, the possibility of false detection of small animals that tend to move around in a narrow short distance range N is reduced, and human body detection in the monitoring zone The prevention of false alarms by small animals in the area close to the device is ensured.
In addition, within the short-range range, when any number of detection areas adjacent to the number of human body determination areas are arbitrarily selected from among a plurality of detection areas, even if the human body moves linearly from any direction, it is selected. The detection area is formed so that the human body moves on all the detection areas. For this reason, even if the detection areas are formed so that the adjacent detection areas are not arranged in series within the short distance range, the human body larger than the size of the small animal moves the adjacent detection areas by the number of human body determination areas. Become. Therefore, it is possible to detect a human body within a short range.

  Next, as shown in FIG. 5, in the long-distance range F, a direction in which three or more detection areas that are the number of human body determination areas are away from the direct position O (radiation direction centered on the direct position O). Are formed so that they are adjacent to each other in series.

  As shown in FIG. 5, within the long distance range F, five sets of detection areas are formed along five different radial directions with the direct position O as the center. That is, in the fan-shaped monitoring zone, the four detection areas b1, b2, a1, and a2 are formed radially along the straight line L and the four radial directions on both sides thereof. Thus, the detection areas b2 and a1 partially overlap in the radial direction.

If the angles formed by the respective directions from the human body detection device to the adjacent detection areas are fixed, the distance between the adjacent detection areas is larger in the distance from the monitoring zone than in the short distance range. For this reason, unless the detection areas are arranged in series within the long-distance range F, which is far from the monitoring zone, infrared rays are detected in three or more detection areas that are the number of human body determination areas even if a human body actually enters. However, according to the human body detection device of the present embodiment, within the long distance range F, the detection areas are arranged in series in the radiation direction in the number of human body determination areas of 3 or more. As a result, misreporting can be reliably prevented.
It should be noted that the area of the detection area is farther away than the detection area in the short distance range. For this reason, even if detection areas adjacent in the distance are arranged in series, a small animal smaller than the human body is not detected.

  Further, according to the present embodiment, the condensing means is configured by a plurality of (two) mirrors, and the plurality of mirrors condense the infrared rays radiated from the monitoring zones onto different pyroelectric elements, respectively. A detection area is formed in the monitoring zone. That is, since a large number of detection areas that divide the monitoring zone are formed by a plurality of (two) mirrors, the shape of each mirror is further simplified as compared to the case where a large number of detection areas are formed by a single mirror. The effect that design and manufacture becomes easier is obtained. In other words, it is possible to form a large number of fine detection areas, particularly in the short distance range N, without performing precise design / production on a single mirror.

<About control means>
The control means 14 shown in FIG. 1 is composed of a microcomputer composed of a CPU, ROM, RAM, etc. and its peripheral circuits, and performs drive control of each means constituting the human body detection device 1. Moreover, the control means 14 is provided with the area determination means 14a and the human body determination means 14b as a functional module implement | achieved by this microcomputer and the computer program run on a microcomputer.

  As shown in FIG. 1, the control unit 14 includes four area determination units 14a so as to correspond to the signal processing units 13a to 13d, respectively. Detection signals from the signal processing units 13a to 13d are independently input to each area determination unit 14a. Each area determination means 14a determines whether or not an object has been detected in the corresponding detection area based on each detection signal, and when there is a signal of a predetermined level within a predetermined determination time T1, The detection signal is determined to be valid (there is a change in infrared rays), and the object detection signal is output to the human body determination means 14b at the subsequent stage. The control means 14 has a timer having a time measuring function in order to time the determination time as a determination reference in the area determination means 14a and the human body determination means 14b.

First, the object detection determination process performed by the area determination unit 14a will be described with reference to FIG. The graph shown in the upper half of FIG. 8 is a timing chart showing the processing contents of object detection by the area determination means 14a.
When an object with a change in infrared energy passes from the + polar area side to the -polar area side in the detection area, the pyroelectric element outputs from the pyroelectric elements a1 to ad are the signal processing means 13a. ˜13d and input to each area determination means 14a as a detection signal as shown in FIG. The area determination unit 14a processes this detection signal based on the + threshold value, the −threshold value, and the determination time T1, and determines whether or not an object exists in the target detection area. That is, the area determination unit 14a starts timing from the time when the detection signal exceeds the + threshold value, and determines that an object exists in the detection area when the threshold value is also exceeded within the determination time T1 (for example, 3 seconds). To do. In the example shown in FIG. 8, the case where the detection signal exceeds the −threshold value just after the determination time T1 from the time when the detection signal exceeds the + threshold value is shown. As described above, the area determination unit 14a sets the detection area when the object passes through the target detection area and the threshold level is exceeded within the determination time T1 after the signal level of the detection signal exceeds the + threshold value. It is determined that an object is present, and this detection signal is validated and an object detection signal is output to the human body determination unit 14b.

  The example in FIG. 8 is a level waveform when an object moves from the + polarity side detection area to the −polarity side detection area, and the object moves from the −polarity side detection area to the + polarity side detection area. In this case, the waveform is the reverse of that in FIG. Further, when the detection signal does not exceed the + threshold value and the −threshold value within the determination time T1, the detection signal is determined to be invalid, the time count of the determination time T1 is reset, and the detection signal is input again to the + threshold value or the −threshold value. When the time exceeds, determination of the determination time T1 is started.

  Next, human body determination processing by the human body determination unit 14b will be described with reference to FIGS. The graph shown in the lower half of FIG. 8 is a timing chart showing the relation between the object detection determination timing in the area determination means 14a shown in the upper half and the human body determination determination timing in the human body determination means 14b. FIG. 9 is a timing chart for explaining the human body determination process in the human body determination unit 14b, and the areas by the area determination units 14a for the four detection areas corresponding to the dual element pyroelectric elements a1, a2, b1, and b2. The determination (area determinations a1 and b2 by the area determination means) is shown.

  As shown in the timing chart of the lower half of FIG. 8 and FIG. 9, the human body determination unit 14b starts measuring the holding time T2 at this input timing when the object detection signal is input from the area determination unit 14a. This signal is held for the holding time T2. The object detection signal is valid only during the holding time T2. The human body determination unit 14b determines that the intruding object is a human body when the object detection signal is input by the amount obtained by subtracting 1 from the number of human body determination areas from other elements during the holding time T2. The human body detection signal as the determination result is output to the output means 15.

  That is, as shown in FIG. 9, the human body determination unit 14b performs the dual element focus detection during the holding time T2 in which the object detection signal based on the second pyroelectric output from the dual element pyroelectric element a2 is held. Since two object detection signals based on the pyroelectric element outputs from the electric elements b1 and b2 are input, three object detection signals that are the number of human body determination areas are input. As shown in the lowermost part of FIG. Then, it is determined that the detected object is a human body, and a human body determination signal is output to the output means 15.

  Note that the human body determination unit 14b holds the input object detection signal after the holding time T2 because the human body detection is not established when no other object detection signal is input while the input object detection signal is held for the holding time T2. Delete the object detection signal.

<About output means>
The output unit 15 receives an input of the human body determination signal output from the control unit 14, and receives a subsequent interlocking device that is an output destination (for example, an alarm device (not shown), a ringing device, and a monitor incorporated in the human body detection device 1. A human body detection signal is output to a camera or the like.

[Processing operation]
Next, a series of operation examples related to the human body detection process of the human body detection device 1 described above will be described.
First, infrared energy radiated from a plurality of detection areas formed in the monitoring zone is condensed on the infrared detecting means 11 by the condensing means 12, and the pyroelectric element output from the infrared detecting means 11 is output by the signal processing means 13. A detection signal indicating the amount of change in energy of the collected infrared light that has been processed is output from the signal processing means 13 to the area determination means 14a.

  Each area determination unit 14a determines whether or not the signal level of the detection signal exceeds the + threshold value or the −threshold value, and starts measuring the determination time T1 at a timing when the input detection signal exceeds any threshold value. To do. When the input detection signal exceeds the other threshold value within the determination time T1, it is confirmed that the object has been detected by the pyroelectric element that has output the detection signal, and the object detection signal indicating this is sent to the human body. It outputs to the determination means 14b.

  The human body determination unit 14b holds this signal for the holding time T2 from the input timing of the object detection signal. Then, the human body determination unit 14b detects within the monitoring zone when the object detection signal detected in the other detection areas is input by the number obtained by subtracting 1 from the number of human body determination areas during the holding time T2. It is determined that the object is a human body, and a human body determination signal indicating this is output to the output means 15.

  The output unit 15 outputs a human body detection signal to the subsequent interlocking device, and the subsequent interlocking device executes a necessary operation using the input human body detection signal.

[Effect of this embodiment]
As described above, the human body detection device 1 according to the present embodiment includes the infrared detection means 11 including the dual twin type first pyroelectric element 11a and the second pyroelectric element 11b, and for each pyroelectric element. Condensing means 12a and 12b are provided, and a plurality of detection areas are formed in the monitoring zone.

  In a human body detection device in which a plurality of detection areas are formed in the monitoring zone, the detection area formed in the monitoring zone is smaller in the detection area formed in front than in the distance. In this detection area, it is easier to generate false alarms by detecting a greater change in infrared rays by a small animal than in a relatively distant detection area.

  Therefore, in this embodiment, paying attention to the behavioral characteristic that small animals moving around in the short distance range N move linearly and rarely change direction in small increments, a plurality of detection areas formed in the monitoring zone Among them, the short distance range N is configured such that the number of detection areas equal to or greater than the number of human body determination areas are adjacent to each other and not arranged in series.

  For this reason, according to the present embodiment, within the short distance range N from the position directly below the human body detection device to the radial direction, the possibility of erroneous detection of a small animal that tends to move linearly within a narrow range is reduced. It is possible to prevent false alarms caused by small animals in an area close to the human body detection device in the monitoring zone.

  Further, in the long distance range F, which is farther than the short distance range N in the monitoring zone, the projected area of the detection area is widened, so if the detection area is not set in series, There is a possibility that a change in infrared rays cannot be determined in a detection area that is equal to or more than a predetermined number of areas serving as a reference for determination.

  Therefore, in the present embodiment, the number of detection areas equal to or greater than the number of human body determination areas is arranged adjacent to each other in series in the radial direction within the long distance range F that is farther than the short distance range N in the monitoring zone. In the long-distance range F, if the detection areas are arranged in series in the radial direction in this way, the width of the detection area is set to about the shoulder width of a person, and the height of the light collection space also substantially matches the height of the person. If this is the case, the possibility that the human body is detected in the three detection areas is sufficiently high, and thus it is possible to reliably prevent misreporting.

  In the embodiment described above, each detection area has a generally elongated rectangular shape as shown in FIG. 1, but this depends on the shape of the mirror in the light collecting means 12 and the element shape in the infrared detection means 11. It may be oval, circular or other shapes. Further, the arrangement pattern of the detection areas in the monitoring zone may be arbitrarily set according to the monitoring purpose. Furthermore, in the present embodiment, the monitoring zone has a shape that is generally recognized as a fan shape in plan view, but is not limited to this, and can be arbitrarily set according to the purpose of monitoring, etc. In view, the fan may have a desired center angle centered on the human body detection device or a position directly below it, or may be circular or other shapes.

DESCRIPTION OF SYMBOLS 1 ... Human body detection apparatus 11 ... Infrared detection means (11a ... 1st pyroelectric element (dual element pyroelectric element a1, a2), 11b ... 2nd pyroelectric element (dual element pyroelectric element b1, b2))
12 ... Condenser mirror (12a ... 1st collector mirror, 12b ... 2nd collector mirror, 12c ... shielding member)
13 ... Signal processing means (13a ... 1st signal processing means, 13b ... 2nd signal processing means, 13c ... 3rd signal processing means, 13d ... 4th signal processing means)
14 ... Control means (14a ... Area determination means, 14b ... Human body determination means)
15 ... Output means A, B ... Detection zone a1, a2, b1, b2 ... Detection area

Claims (2)

A plurality of infrared detecting means for individually detecting infrared rays and outputting signals;
A condensing unit that forms a plurality of detection areas in a monitoring zone set on a monitoring plane as a region for detecting a human body, and that condenses infrared rays emitted from the detection areas on the corresponding infrared detection units; ,
Area determination means for determining the presence or absence of a change in infrared for each of the detection areas based on a signal output from each infrared detection means;
A human body determination means for determining that a human body has been detected and outputting a human body determination signal when the detection area determined by the area determination means has changed to a predetermined number of areas of at least 3 or more;
A human body detection device comprising:
The condensing means is configured such that the number of detection areas equal to or greater than the predetermined number of areas is not arranged in series adjacent to each other within a short distance range that is a predetermined distance away from a position directly below the human body detection device in the monitoring zone. Thus, the human body detection device is characterized in that the detection area is formed. The condensing means are adjacent to each other in a direction in which the number of the detection areas equal to or greater than the predetermined number of areas is away from the direct position within the long distance range that is a range excluding the short distance range in the monitoring zone. The human body detection device according to claim 1, wherein the detection areas are formed so as to be arranged in series.

Images