JP2006226988A - Infrared sensor system - Google Patents

Abstract

To provide an infrared sensor system for detecting a temperature distribution in a room and the presence and behavior of a human body by a simple configuration, control, and signal processing as compared with the prior art.
An infrared sensor, a thermopile signal processing unit, and a pyroelectric sensor, in which a thermopile and a pyroelectric infrared detector are combined so that the indoor temperature distribution detection range and the human body detection range are the same area. Type infrared detector signal processing unit 3, vertical driving means 5 and horizontal driving means 6 for scanning the infrared sensor in the vertical and horizontal directions, and vertical and horizontal controlling the vertical driving means and horizontal driving means. The drive control unit 7 and the area-specific infrared sensor information storage unit 8 are configured.
[Selection] Figure 1

Description

  The present invention relates to an infrared sensor system that detects temperature distribution in a room in a home, presence detection of a human body, behavior detection, and the like.

  Conventionally, there are two methods for measuring temperature in a non-contact manner: a quantum infrared sensor and a thermal infrared sensor. Quantum infrared sensors have high sensitivity and quick response, but require cooling and are not suitable for consumer use. On the other hand, a thermal infrared sensor has a relatively low sensitivity and a low response speed, but has not been cooled, and thus has been put to practical use in the consumer market (for example, see Patent Document 1).

  FIG. 13 shows a thermal image detection apparatus using a pyroelectric infrared sensor having relatively high sensitivity and response speed among the thermal infrared sensors described in Patent Document 1. In FIG. 13, the thermal image detection apparatus includes an infrared sensor composed of a plurality of pyroelectric thermal detection element groups arranged in a one-dimensional manner on a linear axis, an infrared transmission lens, and the infrared transmission lens. A chopper mechanism that controls the amount of infrared rays incident on the pyroelectric heat detection element group, a rotation axis that is inclined by a certain angle with respect to the linear axis, and the pyroelectric heat detection element group that rotates around the rotation axis A two-dimensional thermal image is obtained.

In the conventional configuration, in order to detect the temperature of the object surface, a chopper mechanism for controlling the amount of infrared rays incident on the infrared sensor composed of the pyroelectric heat detection element group is indispensable. In addition, in order to ensure the reliability and accuracy of the detected thermal image, acquisition of signals output from the chopper opening / closing and pyroelectric thermal detection element group, horizontal drive synchronization, and detection of the presence of a human body from a two-dimensional thermal image It was necessary to detect the behavior.
JP-A-6-105236

  However, in such a thermal image detection apparatus using a pyroelectric infrared sensor, a chopper mechanism that controls the amount of infrared light incident on the pyroelectric thermal detection element group is indispensable in order to detect the temperature of the object surface. However, there has been a problem that the structure of the thermal image detection device becomes complicated.

  For thermal image acquisition, detection of the presence of a human body and human body behavior are performed by processing the signals output from the chopper opening and closing, pyroelectric heat detection element group, horizontal drive synchronization, and two-dimensional thermal image processing. There is a problem that it is necessary to perform and perform complicated control and signal processing using a high-performance microprocessor for these processes.

  The present invention solves the above-mentioned conventional problems, and by using an infrared sensor that combines a thermopile and a pyroelectric infrared detector so that the indoor temperature distribution detection range and the human body detection range are the same area, The object is to detect the temperature distribution in the room and the presence and position of the human body and the behavior of the human body by simple configuration, control, and signal processing.

In order to solve the above-described conventional problems, an infrared sensor system of the present invention includes an infrared sensor in which a thermopile and a pyroelectric infrared detector are combined so that an indoor temperature distribution detection range and a human body detection range are the same area. A thermopile signal processing unit, a pyroelectric infrared detector signal processing unit, vertical driving means and horizontal driving means for scanning the infrared sensor in the vertical and horizontal directions, and the vertical driving means and horizontal driving means. It comprises a vertical / horizontal drive control unit to be controlled and an infrared sensor information storage unit for each area.

  Accordingly, it is possible to detect the temperature distribution in the room and the presence and position of the human body and the behavior of the human body with a simpler configuration, control, and signal processing than in the past.

  The infrared sensor system of the present invention can detect the temperature distribution in the room and the presence and position of the human body and the behavior of the human body with a simple configuration, control, and signal processing as compared with the prior art.

  A first invention is an infrared sensor in which a thermopile and a pyroelectric infrared detector are combined so that an indoor temperature distribution detection range and a human body detection range are the same area, a thermopile signal processing unit, and a pyroelectric infrared detector. A signal processing unit, vertical driving means and horizontal driving means for scanning the infrared sensor in the vertical and horizontal directions, vertical / horizontal driving control units for controlling the vertical driving means and horizontal driving means, and for each area It is comprised with an infrared sensor information memory | storage part, and can detect indoor temperature distribution with a simple structure compared with the past.

  According to a second aspect of the present invention, in the infrared sensor system, the horizontal direction driving means is operated so as to overlap the field of view of the left and right infrared sensors, and the horizontal direction is compared with the more accurate infrared sensor system by a relatively simple method. The human body position can be detected.

  According to a third aspect of the present invention, in the infrared sensor system, the vertical direction driving means is operated so as to overlap the visual field of the infrared sensor in the vertical direction. It is possible to detect the human body position in the front-rear direction and to estimate the behavior of the human body.

  According to a fourth aspect of the present invention, in the infrared sensor system, the horizontal driving means causes the left and right infrared sensors to overlap the viewing angle, and the vertical driving means causes the vertical infrared sensors to overlap the visual field. By doing so, it is possible to more accurately detect the relative positions of the human body with respect to the infrared sensor system in the left-right and front-back directions.

  5th invention improves the precision of presence detection of a human body by complementing the information of a pyroelectric infrared detector signal processing part using the time change of the information of a thermopile signal processing part in the said infrared sensor system. be able to.

  According to a sixth aspect of the present invention, in the air conditioner equipped with the infrared sensor system, the horizontal direction driving range of the field of view of the infrared sensor is determined based on the installation information of the air conditioner stored in the air conditioner. Human body detection in a range where no human body can exist can be avoided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 shows a configuration diagram of an infrared sensor system according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes an infrared sensor in which a thermopile and a pyroelectric infrared detector are combined so that the indoor temperature distribution detection range and the human body detection range are the same area. As shown in FIG. 2, the infrared sensor 1 is characterized in that a thermopile hot junction 10 is formed on the light receiving electrode 12 of the pyroelectric infrared detector (see Japanese Patent Laid-Open No. 2000-275100). Thereby, the infrared sensor which makes an indoor temperature distribution detection range and a human body detection range the same area is comprised.

  An electromotive force corresponding to the amount of infrared rays incident from the viewing angle of the infrared sensor is generated between the hot and cold junctions 10 and 11 of the thermopile, and the thermopile signal processing unit 2 converts the temperature of the output signal. , Non-contact temperature detection in the area 4 becomes possible. In addition, a change in the infrared ray incident from the viewing angle of the infrared sensor according to the movement of the person generates a change in the electrical signal of the pyroelectric infrared detector 12 output, which is converted into a pyroelectric infrared detector signal processing unit. By filtering at 3, the human body in the area 4 can be detected.

  Reference numeral 5 denotes vertical driving means for scanning the infrared sensor in the vertical direction to change the temperature distribution detection and human body detection areas in the depth direction of the room, and 6 is the temperature distribution detection and human body detection areas in the horizontal direction. Horizontal driving means for changing. The infrared sensor 1 detects the temperature distribution in the area and the human body in A1 → A2 → A3 → A4 → A9 in FIG. 1 according to the command from the vertical / horizontal direction drive control unit 7 by the two driving means. As a result, temperature distribution detection and human body detection of the entire room are performed.

  The pyroelectric infrared detector 12 generates a signal output against vibration and shock, and the thermopile has a large thermal time constant. Therefore, the vertical / horizontal drive control unit 7, the thermopile signal processing unit 2, and the pyroelectric type are used. The infrared detector signal processing unit 3 is tuned.

  For example, vertical or. After the elapse of 1 to 2 seconds from the horizontal scanning, the temperature distribution in the area and the human body are detected. Thereby, the erroneous detection by the characteristic of a thermopile and a pyroelectric infrared detector can be reduced.

  FIG. 3A shows the time elapse of the output of the pyroelectric infrared detector signal processing unit 3, where ◯ indicates human body detection in the area, x indicates absence of a human body, and _ indicates indefinite. At the same time, human bodies cannot be detected in all areas in the room, so the situation is as shown in FIG. The vertical and horizontal scanning of the infrared sensor is repeated N times and N + 1 times, and the human body position information is stored in the area-specific sensor information storage unit 8. By performing statistical processing on this result, the human body position in the room can be estimated.

  Further, FIG. 3B shows a time lapse of the output of the thermopile signal processing unit 2 and shows a result of radiation temperature in the area. The vertical and horizontal scanning of the infrared sensor can be repeated N times and N + 1 times and stored in the area-specific sensor information storage unit 8.

  Accordingly, it is possible to provide an infrared sensor system that detects the indoor temperature distribution and the presence and position of the human body and the behavior of the human body by simple configuration, control, and signal processing as compared with the related art.

(Embodiment 2)
FIG. 4 shows the configuration of an infrared sensor system according to the second embodiment of the present invention.

In the above-described infrared sensor system, overlapping portions such as A1-A2-A3,..., A7-A8-A9 in FIG. A temperature distribution detection and human body detection area having For example, in A1 and A2 of FIG. 4, when a human body is detected in both areas by the infrared sensor system, it can be estimated that a human body exists in the overlapping area of the vertical line portion of A1 and the horizontal line portion of A2. That is, the human body position in the three areas can be estimated using the logical sum of the human body detection results in the two areas A1 and A2. The same can be said for A2 and A3, and A4-A5-A6 and A7-A8-A9 arranged in the left-right direction with respect to the infrared sensor system.

  Accordingly, it is possible to provide an infrared sensor system that estimates the human body position in the left-right direction more than the detection area by using an inexpensive, simple configuration, control, and signal processing compared to the conventional technology. it can.

(Embodiment 3)
FIG. 5 shows a configuration diagram of an infrared sensor system according to the third embodiment of the present invention.

  In the above infrared sensor system, the vertical direction driving means is operated so as to overlap the visual field of the infrared sensor in the vertical direction, whereby the temperature distribution as shown in A1-A6-A7,..., A3-A4-A9 in FIG. Detection and human body detection areas are obtained. For example, in A2 and A5 of FIG. 5, when a human body is detected in both areas by the infrared sensor system, it can be estimated that a human body exists in an overlapping area of the horizontal line portion of A2 and the vertical line portion of A5. That is, the human body position in the three areas can be estimated using the logical sum of the human body detection results in the two areas A2 and A5. The same can be said for A5 and A8, and A1-A6-A7 and A3-A4-A9 arranged in the front-rear direction with respect to the infrared sensor system.

  FIG. 6 is a vertical light distribution diagram of the infrared sensor viewing angle according to the third embodiment of the present invention. Reference numeral 13 denotes an infrared sensor system, which is installed at a high place in a room to detect a human body. The infrared sensor system 13 has a constant viewing angle in the vertical direction, and is moved by vertical driving means, for example, to detect temperature distribution detection and human body detection areas corresponding to A2, A5 and A8 in FIG. It will be placed on the floor. On the other hand, in the sitting position 14, the chair seat 15, and the standing position 16, the human body has a height, and the area where the human body is detected in A2-A5-A8 differs depending on the state.

  FIG. 7 shows the relationship between the viewing angle of the infrared sensor corresponding to the human body detection area and the posture of the occupant. 17 shows an outline of a limit range in which a human body is detected only in the range of the viewing angle corresponding to A2, and can be estimated as a sitting position in the vicinity of the infrared sensor system 13. 18 schematically shows a limit range in which a human body is detected at a viewing angle corresponding to A2 and A5, and it can be estimated that a human body exists relatively close to the infrared sensor system 13 regardless of the posture. Reference numeral 19 schematically shows a limit range in which a human body is detected at a viewing angle corresponding to A2, A5, and A8, and it can be estimated that a human body exists at a distance from the infrared sensor system 13 regardless of the posture. Reference numeral 20 schematically shows a limit range in which a human body is detected at a viewing angle corresponding to A5 and A8, and it can be estimated that the human body exists relatively far from the infrared sensor system 13 regardless of the posture. 21 schematically shows a limit range in which a human body is detected only in the viewing angle corresponding to A8, and it can be estimated that the human body exists far away from the infrared sensor system 13 regardless of the posture. Of course, the distance from the infrared sensor system to the human body depends on the viewing angle and the elevation angle of the infrared sensor.

  As a result, the human body position in the front-rear direction is estimated by subdividing it beyond the detection area with respect to the infrared sensor system, and the behavior and posture of a part of the human body are less expensive and simpler than conventional methods. It is possible to provide an infrared sensor system that estimates

(Embodiment 4)
FIG. 8 shows the floor surface distribution of the human body position detection area by the infrared sensor system according to the fourth embodiment of the present invention.

In the present invention, the infrared sensor system performs an operation of overlapping the viewing angles of the left and right infrared sensors by the horizontal driving means, and operates so as to overlap the visual fields of the vertical infrared sensors by the vertical driving means. By doing so, an overlapping area of human body detection areas such as 22 can be secured in the left-right direction, and a human body overlapping area such as 23 can be secured in the front-rear direction.

  As a result, in the temperature distribution detection and human body detection areas A1,... A9, the human body detection is sequentially performed by the infrared sensor system 13, and the adjacent temperature distribution detection and human body detection areas A1,. Thus, the human body position can be estimated in an area divided into 25 rooms.

(Embodiment 5)
FIG. 9 shows a flow of human body detection by the infrared sensor system in the fifth embodiment of the present invention. The pyroelectric infrared detector 12 of the infrared sensor system 13 generates a signal output even with respect to vibration, impact, and change in the incident infrared ray from the outside. Therefore, according to the movement of the viewing angle of the infrared sensor, it depends on the behavior of the human body. An unnecessary human body detection signal is generated due to a cause other than a change in incident infrared rays. Therefore, the human body detection information capture by the pyroelectric infrared detector 12 is prohibited (902) from the start of viewing angle movement (901). In addition, since the time constant of the pyroelectric infrared detector 12 is 0.5 to 1 Hz even after the viewing angle movement is completed (903), unnecessary human body detection signals continue for T1 time (about 1 to 2 seconds). Therefore, for a time period T1 after the end of viewing angle movement, the determination of the presence of a human body by the pyroelectric infrared detector 12 is a prohibited time zone.

  FIG. 10 (a) shows the time change of the radiation temperature 25 of the area calculated by the output signal 24 of the pyroelectric infrared detector 12 and the thermopile signal processing unit when there is no human behavior at time T1 26. It is. By appropriately setting the T1 time 26, it is possible to avoid erroneous detection of human body presence. However, the movement and behavior of the human body may occur only within the T1 time 26.

  On the other hand, the temperature time constants of the indoor walls and floors are long, and the occurrence of temporal changes in the area radiation temperature determined by the thermopile signal processing unit is considered to be a large behavior or movement of the human body. FIG. 10B shows the time change of the output signal 24 of the pyroelectric infrared detector 12 and the radiation temperature 25 of the area calculated by the thermopile signal processing unit when the movement or behavior of the human body occurs within the T1 time 26. Indicated. A time change of ΔT or more of the radiation temperature 25 of the area occurs with a large behavior or movement of the human body.

  Therefore, during T1 time 26, the presence of a human body is determined by detecting time change (904, 905, 906) of ΔT or more of the area radiation temperature obtained by the thermopile signal processing unit (907).

  This can prevent erroneous human detection within T1 time 26 due to the characteristics of the pyroelectric infrared detector, and human body detection by the thermopile signal processing unit is possible as a supplement to prohibiting pyroelectric infrared detection within T1 time 26. Thus, it is possible to reliably perform the human body presence determination in the room or in the area.

(Embodiment 6)
FIG. 11 shows the configuration of an infrared sensor system mounted on an air conditioner according to the sixth embodiment of the present invention. The thermopile signal processing unit 2, pyroelectric infrared detector signal processing unit 3, vertical / horizontal drive control unit 7, and area-specific sensor information storage unit 8 are configured in the control device 28 of the air conditioner. Moreover, it also has the installation information storage part 27 of air conditioners, such as indoor right end installation and left end installation, and can determine the horizontal direction drive range of the visual field of an infrared sensor based on the installation information of an air conditioner.

  FIG. 12 shows the temperature distribution detection and human body detection area when the air conditioner 29 is installed at the right end of the room. A3, A4, and A9 are areas where a human body cannot exist. For these three areas, temperature distribution detection and human body detection are not required. Therefore, while A1-A2-A3-A4-A5-A6-A7-A8-A9 and temperature detection and human body detection were sequentially performed, A1-A2-corresponding to the installation state of the air conditioner 29 The horizontal direction driving means and the vertical direction driving means can be controlled to perform temperature distribution detection and human body detection with A5-A6-A7-A8.

  As a result, the number of areas in which indoor temperature distribution detection and human body detection are performed can be reduced, and the indoor temperature distribution detection and human body detection cycle per room can be shortened. The time difference between the human body position detection time point and the actual human body position is reduced, and more accurate human body position information can be obtained.

  As described above, the infrared sensor system according to the present invention is capable of detecting the temperature distribution in the room and detecting the behavior, position, and occupancy of the human body with a simple configuration as compared with the prior art. It can be used for applications such as ventilation fans and air purifiers.

  In particular, it is suitable for comfortable air-conditioning control of an indoor space such as an air conditioner whose refrigeration cycle is controlled at intervals of 30 to 60 seconds.

Configuration diagram of infrared sensor system in Embodiment 1 of the present invention Configuration diagram of infrared sensor with temperature distribution detection range and human body detection range as the same area (A) Explanatory drawing of the pyroelectric infrared detector signal processing part output result in the information storage part classified by area in Embodiment 1 of this invention (b) Thermopile signal in the information storage part classified by area in Embodiment 1 of this invention Explanation of processing unit output result Configuration diagram of infrared sensor system in Embodiment 1 of the present invention Configuration diagram of infrared sensor system in Embodiment 2 of the present invention Vertical light distribution diagram of infrared sensor viewing angle in the third embodiment of the present invention Relationship diagram between infrared sensor viewing angle and occupant's posture Floor surface distribution map of human body position detection area of infrared sensor system in fourth embodiment of the present invention Flowchart of human body detection process of infrared sensor system in the fifth embodiment of the present invention (A) The figure which shows the time change of the pyroelectric infrared detector output signal radiation temperature when there is no human body behavior (b) The time change of the pyroelectric infrared detector output signal radiation temperature when there is a human body behavior Illustration The block diagram of the infrared sensor system mounted in the air conditioner in the 6th Embodiment of this invention The figure which shows the temperature distribution detection and human body detection area when the air conditioner is installed in the right end of the room Sectional view of a conventional thermal image detector

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Infrared sensor 2 Thermopile signal processing part 3 Pyroelectric infrared detector signal processing part 4 Area 5 Vertical direction drive means 6 Horizontal direction drive means 7 Vertical / horizontal drive control part 8 Area-specific sensor information storage part 10 Thermopile hot junction 11 Thermopile Cold junction 12 Pyroelectric infrared detector 14 Sitting position 15 Chair 16 Standing position 17 Limit range where a human body is detected only within the range of the viewing angle of A2 18 Limit range where a human body is detected at the viewing angles of A2 and A5 19 A2, Limit range in which a human body is detected at the viewing angles of A5 and A8 20 Limit range in which a human body is detected at the viewing angles of A5 and A8 21 Limit range in which a human body is detected only at the viewing angle of A8 22 Human body detection area in the horizontal direction Overlap area 23 Overlap area of human body detection area in the front-rear direction 24 Time change of output signal of pyroelectric infrared detector 12 25 Thermopie The signal processing unit time of the radiation temperature of the calculated area by changing 26 unnecessary human body detection signal do not get time 27 air conditioner installation information storage unit 28 an air conditioner control device 29 air conditioner

Claims (6)

An infrared sensor in which a thermopile and a pyroelectric infrared detector are combined so that the indoor temperature distribution detection range and the human body detection range are the same area, a thermopile signal processing unit, a pyroelectric infrared detector signal processing unit, Vertical direction drive means and horizontal direction drive means for scanning the infrared sensor in the vertical and horizontal directions, vertical / horizontal drive control section for controlling the vertical direction drive means and horizontal direction drive means, and infrared sensor information storage section for each area An infrared sensor system characterized by comprising: 2. The infrared sensor system according to claim 1, wherein in the infrared sensor system, the horizontal direction driving means is operated so as to overlap the visual fields of the left and right direction infrared sensors. 2. The infrared sensor system according to claim 1, wherein the infrared sensor system is operated by vertical driving means so as to overlap the visual field of the vertical infrared sensor. In the infrared sensor system, the horizontal direction driving means is operated so as to overlap the viewing angles of the left and right direction infrared sensors, and the vertical direction driving means is operated so as to overlap the visual fields of the vertical direction infrared sensors. The infrared sensor system according to claim 1. 2. The infrared ray according to claim 1, wherein in the infrared sensor system, the position of a human body in a room is estimated based on time changes of information of a pyroelectric infrared detector signal processing unit and information of a thermopile signal processing unit. Sensor system. 2. An air conditioner equipped with the infrared sensor system, wherein a horizontal driving range of the field of view of the infrared sensor is determined based on installation information of the air conditioner stored in the air conditioner. The infrared sensor system according to claim 1, 2, or 4.

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