JP3403246B2 - Passive infrared detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermopile, a pyroelectric
Passive infrared for mechanical security using ceramics, etc.
The present invention relates to a detection device. [0002] 2. Description of the Related Art Infrared energy radiated from the human body
Passive red that uses to detect the presence of intruders
Outside line detectors are widely used in mechanical security systems
ing. This type of passive infrared detector is designed to display intruders.
Far-infrared energy radiated from the surface is converted to electrical energy
For example, to convert to pyroelectric ceramics
It is equipped with a conversion element, and one
Or when intruders cross multiple sensitive zones
The level change of the output signal generated from the conversion element
Is configured to detect the presence of [0003] This will be described in more detail.
Radiation from intruders as they cross the city zone
Of the output signal generated by the conversion element in response to the infrared
The magnitude of the change in level in a given direction is determined by the level of the output signal.
Is measured by the time when exceeds the specified reference value.
Configuration to determine that there is an intruder if the time is longer than the specified time
It is. [0004] Therefore, the conventional receiving device
What kind of discrimination algorithm does the dynamic infrared detector use?
Regardless, by adjusting the above reference value,
Intruder output and small animals or sunlight, drafts, cooling and heating
Distinguishes between spontaneous output from bunch etc.
Adjusted to give alert output only in response to intruders
There is a need. [0005] However, it is necessary to reliably detect intruders.
If you attempt to do so, you must set the reference
It is necessary to respond to small animals and generate false alarms.
Performance will increase. Especially for mechanical security systems.
In addition, this type of false alarm increases the number of unnecessary dispatches of patrols.
If you increase the operating cost of the mechanical security system,
Problem arises. [0006] The object of the present invention is, therefore, to address the prior art.
Improved passives that can solve the above problems
To provide a type infrared detecting device. [0007] That is, the present invention provides a low-level device other than an intruder.
The presence or absence of an infrared radiation source.
To be able to accurately determine the presence or absence of
To provide an improved passive infrared detector
Things. [0008] [0009][Means for Solving the Problems] To solve the above problems
The features of the present invention are: From multiple preset monitoring fields
Red to get electrical output according to the input infrared level of
Outside line-to-electrical converter, and output from the infrared-to-electrical converter
Significant change in infrared input level per predetermined time in response to a signal
Measuring means for measuring the number of times of
Intrusion detection information when the number of significant changes is equal to or greater than a predetermined number
Passive infrared detector comprising:
In the sensing device, the number of times of the significant change in response to the
Whether the number reaches a predetermined level less than the predetermined number of times
Identification means for identifying whether or not the identification information is provided, and the identification means and the first output
Means that the number of significant changes has reached the predetermined level.
The intrusion detection information within a predetermined time after reaching
If no false intrusion detection information is output
And two output means. [0010] [0011] [0012][Action] According to a feature of the invention, Intruders move
Greatly changes the infrared input level of each monitoring field of view.
You. Significant level of output signal from infrared-electrical converter
The number of changes does not exceed a predetermined number per predetermined time.
Intrusion detection indicating presence of an intruder from the first output means
Information is output. On the other hand, a significant change was observed in the level of the output signal.
The number of significant changes per predetermined time
, Even if it does not reach
The predetermined number of times that the number of significant changes is less than the predetermined number
The bell has been reached and a second output means
Within a predetermined time since this identification was performed in
It is determined that intrusion detection information was not output to
Although it cannot be said that there is an intruder, invasion of small animals etc., the sun
Similar to the case of an intruder due to light, draft, etc.
Pseudo intrusion detection information indicating that
You. [0014] BRIEF DESCRIPTION OF THE DRAWINGS FIG.
Will be described in detail. FIG. 1 shows a passive infrared ray according to the present invention.
It is a block diagram of one example of a detection device. Passive infrared
The detection device 10 detects the input red from a preset monitoring field of view.
Infrared rays for outputting an output signal P corresponding to the outside line level
Processing the output signal P with the electric conversion unit 11 and
Process to output information for determining the presence or absence of an intruder
A road 12 is provided. In FIG. 1, reference numeral 13 denotes a power source.
DC output from the power supply unit 13 is a regulator 1
4 and the stabilized DC voltage + Vcc
As shown in FIG. The infrared-electric conversion unit 11 is a pyroelectric ceramic.
Infrared-electric conversion element (not shown) comprising
For forming the two sensitive zones Z1, Z2
And a medical device (not shown)
An infrared sensor unit 22 having a known configuration.
You. Illustration stored in the infrared sensor unit 22
For the infrared-to-electric conversion element that does not
DC voltage + Vcc is supplied from the
For example, when an intruder enters the zone Z1, Z2, the radiation red
The voltage signal E corresponding to the level of the outside line is
Output from the port 22. In this embodiment, the voltage signal E is
This voltage signal is applied to a resistor 23 for
E is amplified by the amplifier 24, and the amplified output signal is
Input to the processing circuit 12 as the output signal P of the electric conversion unit 11
Is forced. Note that the resistor 23 and the amplifier 24 are
Needless to say, it may be configured to be housed in one. FIG. 2 shows the sensitive zones Z1, Z2.
Like the level change of voltage signal E when intruder X crosses
An example of a child is shown. As can be seen from FIG.
When there is no intruder in the active zones Z1 and Z2
, The value of the voltage signal E was kept constant at approximately 1/2 of Vcc.
Have been. The sensitive zone Z1 is located in the positive detection area.
Intruder X crosses sensitive zone Z1
Then, the value of the voltage signal E greatly changes in the positive direction (increase direction).
Voltage peak IP1 occurs. Meanwhile, sensitive zo
Z2 is a negative detection area, and the sensitive zone
When intruder X crosses Z2, the value of voltage signal E becomes negative.
The voltage peak IP2 occurs due to a large change in the negative direction.
You. The infrared-electrical converter 11 outputs the voltage signal E
Output signal P, which is a voltage signal corresponding to the level change, is output
Is done. When intruder X crosses the sensitive zone
And invading from the magnitude of the peak value generated in the output signal P
Processing circuit 1 to obtain information for determining the presence or absence of
2 are provided. FIG. 3 shows a detailed circuit diagram of the processing circuit 12.
Have been. The processing circuit 12 affects the level of the output signal P.
Voltage levels VH1 and VH1, which are reference levels for detecting an entrant,
And VL1 to determine the presence or absence of an intruder
The level of the output signal P is set to the voltage level VH1
Voltage level VH which is another reference level different from VL1 and VL1
2 and VL2, the level of infrared radiation from intruders
The presence or absence of infrared input above a predetermined low level
And a second determination unit 40 for performing the determination. The first discriminating section 30 receives a signal from the resistance voltage dividing circuit 31
Reference voltage VH1 is input to the − input terminal and the + input terminal
And a voltage comparator 32, to which the output signal P is input.
The reference voltage VL1 from the anti-voltage dividing circuit 33 is input to the + input terminal.
The output signal P is input to its negative input terminal.
And a pressure comparator 34. Reference voltages VH1 and VL
1 is the level SH1, SL1 of the voltage signal E shown in FIG.
Respectively. The comparison output voltage G1 from the voltage comparator 32
Is the clock pulse C from the clock pulse generator 35.
First counter in which L is input as a count pulse
36 is input as a count control signal. First counsel
The level of the comparison output voltage G1 becomes "H"
The clock pulse CL is counted only while the
The level of the output signal M1 is reached by reaching the predetermined value K.
Changes from “L” to “H”. And the ratio
When the level of the comparison output voltage G1 changes from "H" to "L"
The first counter 36 is reset by the timing. Sand
That is, when a positive peak occurs in the output signal P, the output signal P
After the level of the signal P becomes higher than the reference voltage VH1, the first
When the count value of the counter 36 reaches K, the output signal M1
Level becomes “H”, and this “H” level state
Continue until the level of signal P becomes lower than reference voltage VH1
I do. The comparison output voltage G2 from the voltage comparator 34
Indicates that the clock pulse CL is input as a count pulse.
Input to the second counter 37 as a count control signal.
Have been. The second counter 37 measures the comparison output voltage G2.
Only when the bell is "H", the clock pulse CL is
Counting, and when the counted value reaches a predetermined value K,
A structure in which the level of the output signal M2 changes from “L” to “H”
It is good. Then, the level of the comparison output voltage G2 is "H".
The second counter 37 resets at the timing when
Is set. That is, the output signal P has a negative peak.
When this occurs, the level of the output signal P becomes higher than the reference voltage VL1.
The count value of the second counter 37 reaches K after the value has also become smaller.
Then, the level of the output signal M2 becomes “H”,
In the “H” level state, the level of the output signal P is equal to the reference voltage VL.
Continue until greater than one. The output signals M1 and M2 enter the OR gate 38.
And one of the output signals M1 and M2 is
Intrusion detection that becomes "H" level by becoming "H"
The informing signal HL is output from the OR gate 38. That is, the value of the voltage signal E exceeds SH1.
State continues for a time corresponding to the count value K, or
The state where the value of the voltage signal E becomes smaller than SL1 is the count value K.
, The intrusion detection signal HL
Level becomes “H”, which causes an intruder
The presence can be determined. From the above explanation
Thus, the reference level VH1 (SH
1), VL1 (SL1) can be obtained from intruders through experiments, etc.
Is determined to be the optimal value that can reliably detect infrared radiation
You. The same applies to the value of K. Next, the second discriminating section 40 will be described.
The second determination unit 40 determines whether the reference voltage V
H2 is input to the-input terminal, and the + input terminal
A voltage comparator 42 to which the output signal P is input and a resistor
The reference voltage VL2 from the voltage circuit 43 is input to the + input terminal.
The voltage ratio at which the output signal P is input to the input terminal
And a comparator 44. Reference voltages VH2 and VL2
Correspond to the levels SH2 and SL2 of the output current I shown in FIG.
Each corresponds. The comparison output voltage G3 from the voltage comparator 42
Indicates that the clock pulse CL is input as a count pulse.
Is input to the third counter 45 as a count control signal.
Have been. The third counter 45 measures the comparison output voltage G3.
Only when the bell is "H", the clock pulse CL is
Counting, and when the counted value reaches a predetermined value K,
A structure in which the level of the output signal M3 changes from “L” to “H”
It is good. Then, the level of the comparison output voltage G3 is “H”.
The third counter 45 resets at the timing when
Is set. That is, the output signal P has a positive peak.
When this occurs, the level of the output signal P becomes higher than the reference voltage VH2.
The count value of the third counter 45 reaches K after it has increased.
And the level of the output signal M3 becomes "H".
The level state is such that the level of the output signal P is higher than the reference voltage VH2.
Continue until small. The comparison output voltage G4 from the voltage comparator 44
Indicates that the clock pulse CL is input as a count pulse.
Input to the fourth counter 46 as a count control signal.
Have been. The fourth counter 46 measures the comparison output voltage G4.
Only when the bell is "H", the clock pulse CL is
Counting, and when the counted value reaches a predetermined value K,
A structure in which the level of the output signal M4 changes from “L” to “H”
It is good. Then, the level of the comparison output voltage G4 is "H".
The counter 46 resets at the timing when
Is set. That is, the output signal P has a negative peak.
When this occurs, the level of the output signal P becomes higher than the reference voltage VL2.
The count value of the fourth counter 46 reaches K after the value has also become smaller.
Then, the level of the output signal M4 becomes “H”,
In the “H” level state, the level of the output signal P is equal to the reference voltage VL.
Continue until greater than 2. The output signals M3 and M4 enter the OR gate 47.
And one of the output signals M3 and M4 is
Low level which becomes “H” level state by becoming “H”
The infrared detection signal OL is output from the OR gate 47.
You. That is, the value of the voltage signal E exceeds SH2.
State continues for a time corresponding to the count value K, or
The state where the value of the voltage signal E becomes smaller than SL2 is the count value K.
Radiation from an intruder if it lasts longer than the time corresponding to
Infrared light above a predetermined low level that is lower than the infrared level
The low-level infrared detection signal OL, which indicates that power has been applied,
Is output. Therefore, it is used in the second discriminating section 40.
The values of the reference voltages VH2 and VL2 are shown in FIG.
Thus, for example, when the small animal Y is the sensitive zone Z1, Z
2 caused by a change in the voltage signal E as it crosses
At the level where the peak values IP3 and IP4 can be detected.
As described, it is appropriately determined based on experiments and the like. Next, the operation of the processing circuit 12 will be described with reference to FIG.
This will be described in detail with reference to FIG. The level of the output signal P is
Explanation will be given by taking the case where it changes as shown in (a) as an example.
Then, the comparison output voltages G1 and G3 become the level of the output signal P.
When the voltage exceeds the reference voltages VH1 and VH2 respectively
High level state only (see (b) and (d) of FIG. 5).
See). On the other hand, the comparison output voltages G2 and G4
The levels are lower than the reference voltages VL1 and VL2, respectively.
High level state only when the operation is performed (FIG. 5 (c),
(E)). The comparison output voltage G1 thus obtained is
To G4 are counting control signals to counters provided correspondingly.
The high level state of each comparison output voltage is
The predetermined time t until the counter value reaches the predetermined value K
It is measured whether or not it is continuing. Therefore, the comparison
When the input voltage goes from low to high
After the time t has elapsed, the corresponding output signals M1 to M4
The bell becomes a high level ((f), (s) (h) in FIG. 5,
(See (i)). In the case of the example of the level change shown in FIG.
In the case, the intrusion detection signal HL and the low-level infrared detection signal
Each level of OL is as shown in (j) and (h) of FIG.
Will change. Therefore, the intrusion detection signal HL
Intruders are detected when the level of
Of course, the intrusion detection signal H
Despite the fact that the level of L remains low,
The infrared detection signal OL has a high level
Some sort of cause other than intruders, such as small animals
It is possible to determine that the user has entered the area. In addition,
Input detection signal HL and low-level infrared detection signal OL
If they happen to be in a high state,
For example, the high-level state of both signals generated per unit time
Also checks the difference in the frequency of the state, low-level infrared detection signal
The frequency at which OL is at a high level depends on the intrusion detection signal HL.
If the number is extremely large, small animals
It can be determined that the possibility is extremely high. As described above, the passive infrared detecting apparatus 1
The first determining unit 30 has a function of determining the presence or absence of an intruder.
In addition, certain lower than infrared radiation level from intruder
A second format to determine the presence or absence of infrared input above the level
A separate unit 40 is provided, and the low-level infrared detection
Since the configuration is such that the knowledge signal OL is output,
In the case of an intruder in the specified alert area,
It can be detected separately from the case where it is inserted. You
That is, based only on the determination result in the first determination unit 30,
Signal to detect the presence of an intruder.
Considering both HL and low level infrared detection signal OL
Intruder presence is more accurately determined by intruder presence
Can be understood. Incidentally, in the embodiment of FIG.
The case where there are two
The configuration of the region is not limited to this.
It is sufficient if there are two sensitive zones.
In some cases, only one set of reference levels is needed.
Is easily understood from the description of the above-described embodiment.
Where you can do it. In addition, positive and negative sensitive
Intrusion by determining whether or not the
The same processing can be performed even when performing person identification. Next, the passive infrared detecting device shown in FIG.
Another embodiment will be described. This passive infrared detecting device 50 is also
More accurately determine the presence or absence of an intruder.
Input infrared ray from a plurality of monitoring fields set in advance.
Infrared-to-electric conversion to obtain electrical output according to the bell
A section 51 is provided. The infrared-electric conversion unit 51 is
Infrared-electric conversion element (shown
) And a plurality of sensitive zones W1, W2,.
An optical device (not shown) for configuring the WN and a case
61, an infrared sensor unit having a known configuration.
A knit 62 is provided. In this embodiment, the sensitive
The zones W1, W2,..., WN have a detection polarity of 1
Every other is positive (+) and negative (-).
In response to entering or leaving these sensitive zones
The level-changed voltage signal U is supplied to the infrared sensor unit 62.
Output from The voltage signal U is used for impedance conversion.
Applied to the resistor 63. This voltage signal U is supplied to the amplifier 64
, And the amplified signal is
It is taken out as an output signal Q and inputted to the measuring section 52.
You. The input resistor 63 and the amplifier 64 are housed in the case 61.
It is good also as a structure to store. In the embodiment shown in FIG.
Illustrates the power supply system that supplies the stabilized DC voltage + Vcc to each part
It has been omitted. FIG. 7A shows a sensitive zone W
1, W2, ... when an intruder crosses
The state of the level change of the output signal Q corresponding to the pressure signal U
An example is shown. As you can see from this waveform, the intruder
The level increases in the positive and negative directions as the
Change. Returning to FIG. 6, the intruder is sensitive
, W1, W2,...
Measure the number of significant changes per level that occur in the level
Therefore, the output signal Q is input to the measuring unit 52. Real truth
In the case of the present embodiment, the output signal Q is
Positive reference voltage PL and predetermined negative reference voltage NL and level
Are compared (see FIG. 7A), and based on the result of the comparison.
The positive and negative peaks occurring in the output signal Q are detected for a predetermined time.
By counting the number of positive and negative peaks
The number of significant changes in the input infrared level per unit time is measured.
Configuration. Referring to FIG. 8, the configuration of the measuring section 52 will be described.
explain in detail. 71 is a first level discriminating unit,
The reference voltage PL obtained by the voltage dividing circuit 72 and the output signal Q
The level is compared by the voltage comparator 73, and the level of the output signal Q is
Is higher than the reference voltage PL, the output of the voltage comparator 73 is
The configuration is such that the level of the force line 73A is in a high level state.
On the other hand, reference numeral 74 denotes a second level discriminating unit, which
The reference voltage NL obtained in step 5 and the output signal Q are used as voltage comparators.
The level is compared at 76, and the level of the output signal Q is
The output of the voltage comparator 76 when the level is lower than NL
In this configuration, the level of the line 76A is set to a high level state. Each output line 73 of the voltage comparison circuits 73 and 76
A and 76A are connected to the input of the OR gate 77,
From the OR gate 77, the peak detection shown in FIG.
The knowledge output CP is output. The peak detection output C thus obtained
Check the significance of each pulse of P based on its pulse width.
The peak detection output CP generates a clock pulse.
The clock pulse CL from the creature 78 is used as a counting pulse.
A signal for counting control is input to the counter 79 which is being input.
Has been entered. The period of the clock pulse CL is
To measure the duration of each pulse of the peak detection output CP.
The counter 79 is set to a relatively short cycle.
The level of the peak detection output CP changes from low to high
Start counting the clock pulse CP from the time when it changes
You. Then, when the count value reaches a predetermined value K, it is output.
The level of the force line 79A becomes high. This high level
The state of the peak detection output CP is changed from high level to low level.
To the point where it changes to Therefore, the counter
From 79, a significant pulse output of the waveform shown in FIG.
OP is obtained. As can be seen from FIG. 7, the first output signal Q
Slightly exceeds the reference voltage level PL, such as a positive peak value.
Are identified by the first level discriminating unit 71
Even if the count value of the counter 79 reaches the predetermined value,
Output as a significant pulse output OP
Never be. Thus, in this embodiment, the output signal
Of each peak of signal Q at a predetermined reference voltage level
Significant peak when the time length exceeds the specified value
And the significant pulse output corresponding to the significant peak
Is output from the counter 79.
You. Returning to FIG. 8, this significant pulse output OP
Change of output signal Q per predetermined time based on
A circuit for counting the number of times
And the counter 82 as shown in the figure.
Therefore, it is constituted. Timer 80 outputs significant pulse output O
In response to P changing from low to high,
The timer pulse TP having a predetermined pulse duration M
It is a configuration to output. This pulse time width M is
After the Lus TP has been output once,
It is not affected by the pulse output OP. The timer pulse TP is applied to the AND gate 81.
In addition to being input as a
It is input as a pulse for numerical control. Counter 82
Is set by the rise of the timer pulse TP and counts
Possible state, and then occur during the pulse duration M
The number of pulses of the significant pulse output OP is counted. Accordingly
The counter 82 outputs a count value indicating the count value there.
The power KS is the number of significant changes in the infrared input level per predetermined time
It will be output as data indicating the number. The count output KS is, as shown in FIG.
Whether the number of significant changes is equal to or greater than a predetermined number
And if it is more than a predetermined number of times, intrusion
The alarm signal KH is input to the first output unit 53 that outputs the signal.
You. Referring to FIG. 9, the first output unit 53 is a
Circuit 91 and a first reference value setting device 92, and the first reference value
The first reference count value data KK set by the setter 92
Is compared with the count output KS. This first reference count value data
The content of data KK is the number of significant pulses within the time width M.
Criteria for judging presence of intruder when output is counted
Values and should be determined experimentally and / or empirically.
It is something that can be done. In this embodiment, it is set to 4.
Therefore, when the content of the count output KS becomes 4, the comparison circuit
The coincidence output IS is output from the
The vibrator 93 is triggered by this, and an intrusion alarm
Signal KH is output for a predetermined time. As can be seen from the above description, the pulse time width M
And the value of the first reference count value data KK are detected by an intruder.
Various experimental data and experience to ensure accurate knowledge
It can be set to an appropriate value based on this. Referring back to FIG. 6, the present device 50 is used by an intruder.
To make it more accurate
The significant change in the infrared input level over a given period of time
The number of times becomes four times indicated by the first reference number value data KK.
Not reached, but not more than a predetermined number within a preset period
If there is a significant change above, separate the false alarm signal.
It has a function to output immediately. For this reason, in this device 50
Responds to the count output KS and the number of significant changes reaches two
Identification unit 54 for identifying whether or not the
Identification indicating that the number of significant changes to be applied has reached 2.
False alarm signal GK in response to force SS and intrusion alarm signal KH
And a second output unit 55 that outputs the same. Referring to FIG. 10, the identification unit 54 is provided with the second
Second reference count value data output from the reference setter 101
The comparison circuit 102 compares KL with the count output KS.
Configuration. In this embodiment, the second reference count value
Since the content of data KL is set to twice, counting
When the content of the force KS becomes 2, the identification output SS is output.
It is. The identification output SS is output from the second output unit 55
Is applied to the set input S of the
Flip-flop 11 at the rising timing of force SS
1 is set, and the output Q is at a high level. This
As a result, the timer 112 is started, and the D flip
Whether the trigger of the flop 113 has a low input T level
Change to a higher level. D flip flop 113
Is reset by the timer 114 during the immediately preceding operating cycle.
Output, its output Q remains low.
You. Here, the number of significant changes per predetermined time is 4
Time set by the timer 112 before reaching
Has elapsed, the output of the flip-flop 111
When the output of timer 112 is
Level to low level, and D flip flop 113
Is in a high level state. The signal from this output Q
Is output as a pseudo alarm output GK and the timer 1
14 is applied as a start signal. Timer 114 starts
After a lapse of a predetermined time from the start, the D flip-flop 113
A reset signal to a reset input R. This
The output Q of the D flip-flop 113 is low.
Will be returned. At the same time, the output QA goes high.
Flip-flop 1 through the OR gate 115
11 is reset. On the other hand, the identification output SS is output and the timer 1
12 is started and then set by timer 112
Number of significant changes per specified time until the timer expires
When the number reaches 4 and the intrusion alarm signal KH is output
Indicates that the intrusion alarm signal KH is free via the OR gate 115.
Applied to the flip-flop 111 and the flip-flop
Since 111 is reset, the false alarm signal GK
Is not output. As can be seen from the above description, the infrared input level
When the number of significant changes in the bell per predetermined time reaches four
, An intrusion alarm signal KH is output from the first output unit 53,
It can be notified that an intruder has been detected. this
In contrast, the number of significant changes reached two, but four
The state that has not been reached is set by the timer 112.
After a certain period of time, it cannot be declared that there is an intruder
However, some abnormality such as entry of small animals has occurred.
Is output. Therefore, similar to the embodiment of FIG.
First, the state of occurrence of these two alarm signals KH and GK is solved.
Analysis of events occurring in the alert area
These two alarms can be grasped with the accuracy of
Precisely determine the presence or absence of an intruder based on the notification signals KH and GK
It can be carried out. Note that a significant change in the infrared input level
How to detect the number of times, how many significant changes
To generate an alarm output in case of
The conditions for the occurrence of phenomena are limited to those described in this example.
It is needless to say that this is not a
You. [0058] [0059]【The invention's effect】 According to the present invention, as described above, Set in advance
Time of infrared input level from multiple monitored fields of view
Configuration to detect intruders based on the number of significant changes per interval
In the number of significant changes to determine that there is an intruder
If a predetermined condition that is less than
Since it outputs the intelligence information,
The current low-level infrared radiation situation
be able to. Therefore, also in this case, the first and second
2 By considering each information content from the output means,
The presence or absence of an intruder can be determined more accurately.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing one embodiment of a passive infrared detection device according to the present invention. FIG. 2 is a voltage waveform diagram showing an example of a change in output voltage from the infrared sensor unit shown in FIG. FIG. 3 is a detailed circuit diagram of the processing circuit shown in FIG. 1; FIG. 4 is a voltage waveform chart showing an example of a change in output voltage of the infrared sensor unit shown in FIG. 1 when a small animal enters. FIG. 5 is a waveform chart of signals of respective units for explaining the operation of the processing circuit shown in FIG. 3; FIG. 6 is a block diagram showing another embodiment of the passive infrared detection device according to the present invention. FIG. 7 is a waveform chart showing an example of a signal waveform of each unit for explaining the operation of the passive infrared detection device shown in FIG. 6; FIG. 8 is a circuit diagram of a measuring unit shown in FIG. 6; FIG. 9 is a detailed block diagram of a first output unit shown in FIG. 6; FIG. 10 is a detailed block diagram illustrating a detailed configuration of an identification unit and a second output unit illustrated in FIG. 6; DESCRIPTION OF SYMBOLS 10, 50 Passive infrared detection device 11, 51 Infrared-electric conversion unit 12 Processing circuit 22 Infrared sensor unit 30 First determination unit 40 Second determination unit 52 Measurement unit 53 First output unit 54 Identification unit 55 2nd output part GK False alarm output HL Intrusion detection signal KH Alarm output OL Low-level infrared detection signal P, Q Output signal X Intruder Y Small animal

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01V 8/12 G01J 1/42 G01J 5/02

Claims (1)

(57) [Claims] [Claim 1] Input from a plurality of monitoring fields set in advance
Infrared to obtain electrical output according to the power infrared level
An electrical converter and an output signal from the infrared-electrical converter
Response time of the infrared input level per predetermined time
Measuring means for measuring the number;
Outputs intrusion detection information when the number of changes is
Passive infrared detecting device comprising:
The number of significant changes in response to the measuring means is the predetermined number of times.
Less than a predetermined level.
Another means, and the significant change in response to the identification means and the first output means.
When the number of times reaches a predetermined level and reaches a predetermined level
If the intrusion detection information is not output during
And a second output means for outputting intrusion detection information .