JPH08122145A - Infrared detector - Google Patents
Infrared detectorInfo
- Publication number
- JPH08122145A JPH08122145A JP26042594A JP26042594A JPH08122145A JP H08122145 A JPH08122145 A JP H08122145A JP 26042594 A JP26042594 A JP 26042594A JP 26042594 A JP26042594 A JP 26042594A JP H08122145 A JPH08122145 A JP H08122145A
- Authority
- JP
- Japan
- Prior art keywords
- human body
- temperature
- circuit
- infrared
- infrared detector
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000001514 detection method Methods 0.000 claims abstract description 54
- 230000007423 decrease Effects 0.000 claims abstract description 4
- 230000007613 environmental effect Effects 0.000 claims description 24
- 238000009529 body temperature measurement Methods 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000013459 approach Methods 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
Landscapes
- Photometry And Measurement Of Optical Pulse Characteristics (AREA)
- Geophysics And Detection Of Objects (AREA)
- Arrangement Of Elements, Cooling, Sealing, Or The Like Of Lighting Devices (AREA)
- Burglar Alarm Systems (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は赤外線検出器に係り、よ
り詳しくは、人体から発する赤外線を検出してその人体
の存在を検知し、例えば警報を鳴らしたり照明を点灯し
たりする制御信号を送出する赤外線検出器に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infrared detector, and more particularly, it detects infrared rays emitted from a human body to detect the presence of the human body, and outputs a control signal for, for example, sounding an alarm or turning on a lighting. It relates to an infrared detector for sending.
【０００２】[0002]
【従来の技術】従来の赤外線検出器においては、人体を
検出する際に、この人体周辺の環境温度と人体表面温度
との差を赤外線感熱センサで検出するようにしている。
このため、気温が上昇し、人体周辺の環境温度が人体表
面温度に接近すると、出力信号の波形のレベルが小さく
なってしまうため、これらの差を検出することが困難に
なり、失報（即ち、人体検知信号を出力すべきときに出
力できないこと。）の原因になるという問題があった。2. Description of the Related Art In a conventional infrared detector, when detecting a human body, an infrared thermosensitive sensor detects a difference between the ambient temperature around the human body and the human body surface temperature.
For this reason, when the ambient temperature rises and the environmental temperature around the human body approaches the human body surface temperature, the level of the waveform of the output signal becomes small, making it difficult to detect these differences, resulting in a false alarm (ie , The human body detection signal cannot be output when it should be output.)
【０００３】また従来の赤外線検出器の場合、誤動作防
止のため、パルスカウント機能（例えば、出力信号のレ
ベルがしきい値を超える回数が２回で警報を出す。）を
具備し、通常、警報発生回数を２回に設定している。こ
のため、出力信号のレベルが小さくなってしきい値を超
える回数が１回となった場合、やはり失報の原因になる
という問題があった。Further, the conventional infrared detector is equipped with a pulse counting function (for example, an alarm is issued when the number of times the level of the output signal exceeds the threshold value is 2 times) to prevent malfunction, and usually an alarm is issued. The number of occurrences is set to 2 times. Therefore, when the level of the output signal becomes small and the number of times of exceeding the threshold value becomes once, there is a problem that it also causes a false alarm.
【０００４】このような従来の赤外線検出器における失
報防止対策として、赤外線検出器に温度センサを組み込
み、人体周辺の環境温度が人体表面温度に近付いたと
き、温度センサの検出結果を基に人体検出信号に対する
増幅率を上げる（又はしきい値のレベルを下げる）よう
にする試みもなされている（例えば、特公昭６１−１８
２３６号公報参照）。しかしながら、このような構成に
すると、ノイズマージンが下がり、警報を出力すべきで
ないときに出力してしまう、いわゆる誤報が生じ易いと
いう問題がある。As a measure for preventing a false alarm in such a conventional infrared detector, a temperature sensor is incorporated in the infrared detector, and when the environmental temperature around the human body approaches the human body surface temperature, the human body is detected based on the detection result of the temperature sensor. Attempts have also been made to increase the amplification factor (or lower the threshold level) of the detection signal (for example, Japanese Patent Publication No. 61-18).
236). However, with such a configuration, there is a problem in that a noise margin is reduced and a so-called false alarm is likely to occur, which is an alarm that is output when it should not be output.
【０００５】[0005]
【発明が解決しようとする課題】本発明は、上記事情に
鑑みてなされたものであり、人体周辺の環境温度が人体
表面温度付近になった場合でも、失報や誤報が無く、正
確な人体検出動作を発揮する赤外線検出器を提供するこ
とを目的とするものである。SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and does not cause false alarms or false alarms even when the environmental temperature around the human body is close to the surface temperature of the human body. An object is to provide an infrared detector that exhibits a detection operation.
【０００６】[0006]
【課題を解決するための手段】請求項１記載の発明は、
人体から発する赤外線を検出する赤外線感熱センサと、
この赤外線感熱センサの検出信号のレベルが所定のしき
い値を超える回数を計数する計数回路と、この計数回路
の計数値が所定の設定値ｎ（ｎは正の整数）になったと
き人体検出信号を送出する出力回路とを有する赤外線検
出器において、前記人体周辺の環境温度を検出する温度
検出センサと、この温度検出センサによる人体周辺の環
境温度の検温結果が人体表面温度付近になったとき前記
出力回路の所定の設定値ｎをこれより少ない値に減少さ
せる出力制御回路とを設けたものである。According to the first aspect of the present invention,
An infrared thermal sensor that detects infrared rays emitted from the human body,
A counting circuit that counts the number of times that the level of the detection signal of the infrared thermal sensor exceeds a predetermined threshold value, and a human body detection when the count value of the counting circuit reaches a predetermined set value n (n is a positive integer) In an infrared detector having an output circuit for transmitting a signal, when a temperature detection sensor for detecting the environmental temperature around the human body and the temperature detection result of the environmental temperature around the human body by the temperature detection sensor are close to the human body surface temperature And an output control circuit for reducing the predetermined set value n of the output circuit to a value smaller than this.
【０００７】請求項２記載の発明は、前記出力制御回路
により、温度検出センサによる人体周辺の環境温度の検
温結果が人体表面温度付近になったとき前記出力回路の
所定の設定値ｎを、（ｎ−１）（ｎは１以外の正の整
数）又は（ｎ−２）（ｎは１，２以外の正の整数）に減
少させ、また、上記人体表面温度から温度低下したとき
は前記出力回路の所定の設定値ｎに復帰させる構成とし
たものである。According to a second aspect of the present invention, the output control circuit causes the predetermined set value n of the output circuit to be set when the temperature detection result of the environmental temperature around the human body by the temperature detection sensor is close to the human body surface temperature. n-1) (n is a positive integer other than 1) or (n-2) (n is a positive integer other than 1 or 2), and when the temperature decreases from the human body surface temperature, the output The configuration is such that the circuit is restored to a predetermined set value n.
【０００８】[0008]
【作用】請求項１記載の赤外線検出器における赤外線感
熱センサは、人体から発する赤外線を検出し、検出信号
を送出するが、このとき、計数回路は、赤外線感熱セン
サの検出信号のレベルが所定のしきい値を超える回数を
計数する。また、温度検出センサは、前記人体周辺の環
境温度を検出する。前記出力回路は、前記計数回路の計
数値が所定の設定値ｎ（ｎは正の整数）になったとき人
体検出信号を送出するが、この場合、出力制御回路は、
温度検出センサによる人体周辺の環境温度の検温結果が
人体表面温度付近になったとき前記出力回路の所定の設
定値ｎをこれより少ない値に減少させる。The infrared thermal sensor in the infrared detector according to claim 1 detects infrared rays emitted from the human body and sends out a detection signal. At this time, the counting circuit has a predetermined level of the detection signal of the infrared thermal sensor. Count the number of times the threshold is exceeded. Further, the temperature detection sensor detects an environmental temperature around the human body. The output circuit sends out a human body detection signal when the count value of the counting circuit reaches a predetermined set value n (n is a positive integer). In this case, the output control circuit
When the temperature detection result of the environmental temperature around the human body by the temperature detection sensor is close to the human body surface temperature, the predetermined set value n of the output circuit is reduced to a value smaller than this.
【０００９】これにより、人体周辺の環境温度が人体表
面温度付近になった場合においても、前記出力回路が計
数回路による通常よりも少ない計数値で人体検出信号を
送出することになり、失報や誤報が無くなって正確な人
体検出動作を発揮させるとができる。As a result, even when the environmental temperature around the human body becomes close to the surface temperature of the human body, the output circuit sends the human body detection signal with a count value smaller than usual by the counting circuit, resulting in a false alarm. Accurate human body detection operations can be performed without false alarms.
【００１０】請求項２記載の赤外線検出器によれば、前
記出力制御回路により、温度検出センサによる人体周辺
の環境温度の検温結果が人体表面温度付近になったとき
前記出力回路の所定の設定値ｎを、（ｎ−１）（ｎは１
以外の正の整数）又は（ｎ−２）（ｎは１，２以外の正
の整数）に減少させる構成としたので、人体周辺の環境
温度が人体表面温度付近になった場合においても、前記
出力回路が計数回路による通常よりも１回又は２回少な
い計数値を基に人体検出信号を送出することになり、失
報や誤報が無くなって正確な人体検出動作を発揮する。
また、上記人体表面温度から温度が低下したときは、前
記出力回路の所定の設定値ｎに復帰させる構成としたの
で、環境温度が通常値に戻っても、出力制御回路により
初期の設定値に復帰しえ、同様に失報や誤報が無くな
る。According to the infrared detector of the present invention, the output control circuit causes the temperature detection sensor to detect the ambient temperature around the human body when the temperature is close to the human body surface temperature. n is (n-1) (n is 1
Other than a positive integer) or (n-2) (n is a positive integer other than 1 and 2), so that even when the environmental temperature around the human body becomes near the human body surface temperature, The output circuit sends out the human body detection signal based on the count value which is smaller than the normal count value by the counting circuit once or twice, so that there is no false alarm or false alarm and the accurate human body detection operation is performed.
Further, when the temperature lowers from the surface temperature of the human body, the output circuit is configured to return to the predetermined set value n. Therefore, even if the environmental temperature returns to the normal value, the output control circuit returns the initial set value. You can recover, and likewise, there will be no false alarms or false alarms.
【００１１】[0011]
【実施例】以下、本発明の実施例を図１乃至図３を参照
して詳細に説明する。図１に示す赤外線検出器１は、人
体から発する赤外線を検出し、図２に示す正負連続的な
検出信号Ｓを送出する赤外線感熱センサ２と、この赤外
線感熱センサ２の検出信号Ｓのレベルが図２に示す正負
の所定のしきい値を超える回数、即ち図２に示す例では
２回、図３に示す例では１回、を計数する計数回路３
と、この計数回路３の計数値が所定の設定値ｎ（ｎは正
の整数，２，３，４，５等）になったとき人体検出信号
Ｏを送出する出力回路４と、前記人体周辺の環境温度を
検出する温度検出センサ５と、この温度検出センサ５に
よる人体周辺の環境温度の検温結果が人体表面温度（例
えば３６乃至３７℃）付近になったとき前記出力回路４
の所定の設定値ｎを、これより少ない（ｎ−１）（ｎは
１以外の正の整数）又は（ｎ−２）（ｎは１，２以外の
正の整数）に減少させる出力制御回路６とを有してい
る。なお、この出力制御回路６では、人体周辺の環境温
度の検温結果が人体表面温度より低温に戻ったときは、
出力回路４の所定の設定値ｎに復帰させるようにされて
いる。Embodiments of the present invention will be described in detail below with reference to FIGS. The infrared detector 1 shown in FIG. 1 detects the infrared rays emitted from the human body and sends out the positive and negative continuous detection signals S shown in FIG. 2 and the level of the detection signal S of the infrared heat sensitive sensor 2 A counting circuit 3 that counts the number of times the positive / negative predetermined threshold value shown in FIG. 2 is exceeded, that is, twice in the example shown in FIG. 2 and once in the example shown in FIG.
An output circuit 4 for transmitting a human body detection signal O when the count value of the counting circuit 3 reaches a predetermined set value n (n is a positive integer, 2, 3, 4, 5 etc.), and the human body surroundings Temperature detection sensor 5 for detecting the ambient temperature of the human body and the output circuit 4 when the temperature detection result of the ambient temperature around the human body by the temperature detection sensor 5 becomes close to the human body surface temperature (for example, 36 to 37 ° C.).
The output control circuit for reducing the predetermined set value n of (n-1) (n is a positive integer other than 1) or (n-2) (n is a positive integer other than 1) less than this. 6 and 6. In addition, in the output control circuit 6, when the temperature measurement result of the environmental temperature around the human body returns to a temperature lower than the human body surface temperature,
The output circuit 4 is made to return to a predetermined set value n.
【００１２】この赤外線検出器１の動作は以下のとおり
である。赤外線感熱センサ２は、この赤外線感熱センサ
２の近くに接近する人体から発する赤外線を検出して検
出信号を送出するが、このとき、計数回路３は、赤外線
感熱センサ２の検出信号のレベルが所定のしきい値を超
える回数を計数する。また、温度検出センサ５は、前記
人体周辺の環境温度を検出する。前記出力回路４は、通
常、即ち、前記人体周辺の環境温度が人体表面温度（３
６乃至３７℃）付近ではない場合、前記計数回路３の計
数値が所定の設定値ｎ、例えば、図２に示すように２回
となったとき、人体検出信号Ｏを送出する。The operation of the infrared detector 1 is as follows. The infrared thermal sensor 2 detects infrared rays emitted from a human body approaching the infrared thermal sensor 2 and sends out a detection signal. At this time, the counting circuit 3 sets the level of the detection signal of the infrared thermal sensor 2 to a predetermined level. Count the number of times the threshold of is exceeded. Further, the temperature detection sensor 5 detects the environmental temperature around the human body. In the output circuit 4, normally, that is, when the environmental temperature around the human body is the human body surface temperature (3
6) to 37 ° C.), the human body detection signal O is transmitted when the count value of the counting circuit 3 reaches a predetermined set value n, for example, twice as shown in FIG.
【００１３】一方、前記出力制御回路６は、温度検出セ
ンサ５による前記人体周辺の環境温度の検温結果が人体
表面温度（３６乃至３７℃）付近となった場合、前記出
力回路４の設定値ｎを２回より少ない１回に減少させ
る。On the other hand, the output control circuit 6 sets the set value n of the output circuit 4 when the temperature detection result of the environmental temperature around the human body by the temperature detection sensor 5 is near the human body surface temperature (36 to 37 ° C.). To 1 less than 2 times.
【００１４】これにより、人体周辺の環境温度が人体表
面温度付近になり赤外線感熱センサ２の検出信号Ｓのレ
ベルが低下する場合においても、前記出力回路４が計数
回路３による図３に示すような通常よりも少ない計数値
１回で人体検出信号Ｏを送出することになり、失報や誤
報が無くなって正確な人体検出動作を発揮させることが
できる。なお、人体周辺の環境温度の検温結果が再び人
体表面温度より低温に戻ったときは、これを検出して出
力制御回路６により、出力回路４の所定の設定値ｎに復
帰させる。As a result, even when the environmental temperature around the human body becomes close to the human body surface temperature and the level of the detection signal S of the infrared thermosensitive sensor 2 decreases, the output circuit 4 by the counting circuit 3 as shown in FIG. Since the human body detection signal O is sent out once with a smaller count value than usual, it is possible to perform accurate human body detection operation by eliminating false alarms and false alarms. When the temperature measurement result of the environmental temperature around the human body returns to a temperature lower than the human body surface temperature again, this is detected and the output control circuit 6 restores the predetermined set value n of the output circuit 4.
【００１５】上述した出力制御回路６による出力回路４
の設定値ｎの変更は、２回から１回への変更のほか、３
回から１回又は２回へ、４回から３回又は２回へ、５回
から４回又は３回へというように任意に選定できること
は言うまでもない。なお、本発明は上述した実施例のほ
か、その要旨の範囲内で種々の変更が可能である。Output circuit 4 by the output control circuit 6 described above
In addition to changing the setting value n from 2 to 1,
It goes without saying that it is possible to arbitrarily select from once to once or twice, from four times to three times or twice, from five times to four times or three times. The present invention can be modified in various ways within the scope of the invention in addition to the embodiments described above.
【００１６】[0016]
【発明の効果】請求項１記載の発明によれば、温度検出
センサによる人体周辺の環境温度の検温結果が人体表面
温度付近になったとき、出力制御回路が、前記出力回路
の所定の設定値ｎをこれより少ない値に減少させるよう
にしたので、赤外線感熱センサの検出信号のレベルが低
下する場合でも、失報や誤報が無くなって正確な人体検
出動作を発揮させ得る赤外線検出器を提供することがで
きる。According to the first aspect of the present invention, when the temperature detection result of the environmental temperature around the human body by the temperature detection sensor is close to the human body surface temperature, the output control circuit causes the output control circuit to set a predetermined set value. Since n is reduced to a value smaller than this, an infrared detector capable of exhibiting accurate human body detection operation by eliminating false alarms or false alarms even when the level of the detection signal of the infrared thermal sensor is lowered is provided. be able to.
【００１７】請求項２記載の発明によれば、人体周辺の
環境温度が人体表面温度付近になった場合においても、
出力回路が計数回路による通常よりも１回又は２回少な
い計数値を基に人体検出信号を送出することになり、失
報や誤報が無くなって正確な人体検出動作を発揮させ得
る赤外線検出器を提供することができる。According to the second aspect of the present invention, even when the environmental temperature around the human body is close to the surface temperature of the human body,
The output circuit will send the human body detection signal based on the count value once or twice smaller than usual by the counting circuit, and an infrared detector that can perform accurate human body detection operation without missing or false alarms Can be provided.
【図１】本発明の赤外線検出器の実施例を示すブロック
図である。FIG. 1 is a block diagram showing an embodiment of an infrared detector of the present invention.
【図２】人体周辺の環境温度が人体表面温度付近以外の
場合の赤外線感熱センサの検出信号を示す波形図であ
る。FIG. 2 is a waveform diagram showing a detection signal of the infrared thermal sensor when the environmental temperature around the human body is other than near the human body surface temperature.
【図３】人体周辺の環境温度が人体表面温度付近の場合
の赤外線感熱センサの検出信号を示す波形図である。FIG. 3 is a waveform diagram showing a detection signal of the infrared thermal sensor when the environmental temperature around the human body is near the human body surface temperature.
１ 赤外線検出器 ２ 赤外線感熱センサ ３ 計数回路 ４ 出力回路 ５ 温度検出センサ ６ 出力制御回路 1 infrared detector 2 infrared thermal sensor 3 counting circuit 4 output circuit 5 temperature detection sensor 6 output control circuit
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.6 識別記号 庁内整理番号 ＦＩ 技術表示箇所 Ｇ０８Ｂ 13/191 9419−2Ｅ ─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. 6 Identification code Internal reference number FI technical display location G08B 13/191 9419-2E
Claims (2)
感熱センサと、この赤外線感熱センサの検出信号のレベ
ルが所定のしきい値を超える回数を計数する計数回路
と、この計数回路の計数値が所定の設定値ｎ（ｎは正の
整数）になったとき人体検出信号を送出する出力回路と
を有する赤外線検出器において、前記人体周辺の環境温
度を検出する温度検出センサと、この温度検出センサに
よる人体周辺の環境温度の検温結果が人体表面温度付近
になったとき前記出力回路の所定の設定値ｎをこれより
少ない値に減少させる出力制御回路とを設けたことを特
徴とする赤外線検出器。1. An infrared thermal sensor for detecting infrared rays emitted from a human body, a counting circuit for counting the number of times the level of a detection signal of the infrared thermal sensor exceeds a predetermined threshold value, and a count value of the counting circuit is predetermined. In the infrared detector having an output circuit that sends out a human body detection signal when the set value n (n is a positive integer) is reached, a temperature detection sensor for detecting the environmental temperature around the human body and the temperature detection sensor An infrared detector, comprising: an output control circuit for reducing a predetermined set value n of the output circuit to a value smaller than this when the temperature measurement result of the environmental temperature around the human body is close to the human body surface temperature.
よる人体周辺の環境温度の検温結果が人体表面温度付近
になったとき前記出力回路の所定の設定値ｎを（ｎ−
１）（ｎは１以外の正の整数）又は（ｎ−２）（ｎは
１，２以外の正の整数）に減少させ、また、上記人体表
面温度付近から温度低下したときに前記出力回路の所定
の設定値ｎに復帰させるように構成されていることを特
徴とする請求項１に記載の赤外線検出器。2. The output control circuit sets a predetermined set value n of the output circuit to (n−) when the temperature detection result of the environmental temperature around the human body by the temperature detection sensor is near the human body surface temperature.
1) (n is a positive integer other than 1) or (n-2) (n is a positive integer other than 1 and 2), and when the temperature decreases from around the human body surface temperature, the output circuit The infrared detector according to claim 1, wherein the infrared detector is configured to return to a predetermined set value n.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26042594A JPH08122145A (en) | 1994-10-25 | 1994-10-25 | Infrared detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26042594A JPH08122145A (en) | 1994-10-25 | 1994-10-25 | Infrared detector |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH08122145A true JPH08122145A (en) | 1996-05-17 |
Family
ID=17347761
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP26042594A Pending JPH08122145A (en) | 1994-10-25 | 1994-10-25 | Infrared detector |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH08122145A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010256045A (en) * | 2009-04-21 | 2010-11-11 | Taisei Corp | Wide-area, high-precision human body detection sensor |
| CN102878775A (en) * | 2012-10-25 | 2013-01-16 | 合肥美的荣事达电冰箱有限公司 | Refrigerator and refrigerator control method |
| CN114495070A (en) * | 2018-03-12 | 2022-05-13 | 深圳鼎然信息科技有限公司 | UBI dangerous driving data processing method, device, equipment and storage medium |
-
1994
- 1994-10-25 JP JP26042594A patent/JPH08122145A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010256045A (en) * | 2009-04-21 | 2010-11-11 | Taisei Corp | Wide-area, high-precision human body detection sensor |
| CN102878775A (en) * | 2012-10-25 | 2013-01-16 | 合肥美的荣事达电冰箱有限公司 | Refrigerator and refrigerator control method |
| CN114495070A (en) * | 2018-03-12 | 2022-05-13 | 深圳鼎然信息科技有限公司 | UBI dangerous driving data processing method, device, equipment and storage medium |
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