JP3510736B2 - Object detector - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active type object detector which emits detection light in a detection space and detects an object from a change in the amount of received light reflected in the detection space. The present invention relates to an object detector that emits detection light at time intervals.

[0002]

2. Description of the Related Art Conventionally, various object detectors have been put to practical use, such as those that detect the approach of products in a manufacturing factory line, those that approach people such as automatic doors, and those who intrude into buildings. Has been converted.

Here, a CD (Cash Dispenser) of a financial institution is used.
er: automatic teller machine), an example of an object detector that detects the presence of a CD user will be described.

The object detector sets a region in which a user is present when using a CD as a detection space, and is installed, for example, on the ceiling above the CD. This object detector emits, for example, near infrared rays of detection light in a detection space at regular time intervals, receives reflected light reflected by an object in the detection space, and monitors the amount of detection light received. .

When a person exists in the detection space,
The amount of received light is larger than that when there is no such object. That is, comparing the case where the detection light is reflected by the person and the case where the detection light is reflected by the floor without the person, the attenuation amount is small because the optical path distance of the detection light in which the person exists in the detection space is short. Therefore, the amount of light detected by the object detector increases when a person is present.

Thus, when the amount of received light exceeds a predetermined amount, the object detector outputs a human presence signal and can be used for controlling other devices. For example, when the output signal is input to the CD, the CD operation guidance can be started. Further, in an unmanned store where the CD corner is operated unattended, it can be used to judge the start of a store closing operation such as closing the shutter depending on the presence or absence of this signal in the automatic store opening / closing device.

[0007]

By the way, at the CD corner, a plurality of CDs may be installed adjacent to each other due to space limitations, and an object detector may be installed above each CD.

In this case, the respective object detectors are arranged in such a state that a part of the detection areas overlap each other, and when the object detectors installed adjacent to each other emit light at substantially the same time, the detection by itself is detected. In addition to the light, the detection light emitted from another adjacent object detector is also received, so that it is determined that a person exists even though the person does not exist.

As described above, when the object detectors are arranged so that the detection areas are partially overlapped with each other, the influence of light from other object detectors is exerted even if the object does not exist in the detection space. As a result, the amount of light received increases, and there is a risk that the presence signal of the object will be output and erroneously determined to operate.

The present invention has been made in view of the above problems, and there is no object even in an environment where the detection light emitted by another object detector or other periodic noise is present. It is an object of the present invention to provide an object detector that does not malfunction due to the presence signal of an object despite the fact.

[0011]

In order to achieve the above object, the object detector according to claim 1 of the present invention comprises a light emitting means for emitting detection light in a detection space at a predetermined time interval in a normal state, and A light receiving means for receiving the reflected light from the detection space,
An object determining means for determining presence or absence of an object based on the received light amount of said light receiving means at the time of light emission of the detection light, determines the disturbance determine the presence or absence of disturbance on the basis of the received light amount of said light receiving means definitive before emission of the detection light means, wherein the disturbance judgment unit
When it is determined that ambient light has been detected immediately before the light-emitting means emits light.
The light emission timing of the light emitting means according to the number of times of disturbance detection.
And a light emission timing control means for delaying the light emission at different times .

According to a second aspect of the present invention, the light emitting means for emitting the detection light to the detection space at a predetermined time interval in normal times, the light receiving means for receiving the reflected light from the detection space, and the emission of the detection light. a disturbance determining means for determining the object determining means for determining presence or absence of an object based on the received light amount, the presence or absence of disturbance on the basis of the received light amount of said light receiving means after light emission of the detection light of the light receiving means at the time, the disturbance The determining means is the light emitting means.
When it is determined that ambient light has been detected immediately after flashing, the above-mentioned flash
And a light emission timing control means for advancing the light emission timing of the means.

According to the invention of claim 3, the normal time is a predetermined time period.
Light emitting means for emitting detection light to the detection space at a distance,
Light receiving means for receiving the reflected light from the exit space, and the detection light
Of the object based on the amount of light received by the light receiving means during the light emission of
An object determining means for determining the presence or absence of the detection light,
Is the disturbance due to the amount of light received by the light receiving means after the light emission.
The disturbance determining means for determining the presence or absence, and the disturbance determining means are
When it is determined that ambient light has been detected immediately before the light-emitting means emits light.
The emission timing of the light emitting means to the number of times of disturbance detection.
Depending on the time, the disturbance determination means
It was determined that ambient light was detected immediately after the light emission of the light emitting means.
Occasionally, the light emission timing of the light emission means is accelerated.
And an aiming control means .

[0014]

[0015]

According to the present invention, the detection light is normally emitted from the light emitting means to the detection space at a predetermined time interval. Then, the reflected light from the detection space due to this light emission is received by the light receiving means. The object determining means determines the presence or absence of an object based on the amount of light received by the light receiving means when the detection light is emitted.

Here, immediately before the detection light is emitted from the light emitting means, if the disturbance determining means determines that there is disturbance based on the amount of light received from the light receiving means, the light emission timing control means delays the light emission timing of the light emitting means to emit light. To drive.
At this time, the light emission timing of the light emitting means can be delayed by a different time according to the number of times of disturbance detection when the disturbance determination means determines that there is disturbance. Further, immediately after the detection light is emitted from the light emitting means, if the disturbance determination means determines that there is disturbance based on the amount of light received from the light receiving means, the light emission timing control means advances the light emission timing of the light emitting means to drive light emission.

[0018]

1 is a block diagram showing an embodiment of an object detector according to the present invention, and FIG. 2 is a view showing an example of an installed state of the object detector.

The object detector 1 is provided with a light emitting means 3, a light receiving means 4, a light receiving detection determining means 5, an output means 6, a display means 7, and a light emission timing control means 8 in a case 2 forming an outer housing. Comprises one unit.

As shown in FIG. 2, in the object detector 1, for example, in a CD corner where a plurality of CDs 9 are juxtaposed side by side, a region where a user exists when using the CDs 9 is defined as a detection space E. , A position above each CD 9 (for example, the ceiling) so that a part of the detection space E overlaps with the area Ea.
Is installed in.

The light emitting means 3 comprises a light emitting element 3a and a drive circuit 3b for driving the light emitting element 3a. As the light emitting element 3a, for example, an LED in which a plurality of light emitting diodes that emit near infrared light are arranged in parallel at regular intervals
Composed of arrays. Light of a predetermined wavelength from the light emitting element 3a is applied to the detection space E. The light emitting element 3a is
In addition to a light emitting diode that emits near infrared light, a semiconductor laser may be used, and the emitted light is not limited to near infrared light.

The driving circuit 3b is a light emitting element 3 driven by a DC power source.
a is DC-driven, or the light-emitting element 3a is AC-driven at a predetermined frequency by a built-in oscillator.

The light receiving means 4 includes a light receiving element 4a and a conversion circuit 4 for converting the light received by the light receiving element 4a into an electric signal.
b. As the light receiving element 4a, for example, a photodiode, an avalanche photodiode, a phototransistor, or the like is used, as long as it is sensitive to the light emitted by the light emitting element 3a. The light receiving element 4a receives the near-infrared light from the detection space E and outputs the received light signal to the conversion circuit 4b.

The conversion circuit 4b has a structure including, for example, an amplifier circuit and a smoothing circuit, a predetermined frequency component in the photoelectric current of the light reception signal from the light receiving element 4a is amplified by the amplification circuit, and this amplified AC component is amplified. A smoothing circuit smoothes and outputs a DC electric signal to the received light detection determination means 5. In the DC electric signal at that time, the voltage level indicating the amount of electricity corresponds to the amplitude value of the AC signal, and also corresponds to the amount of received light.

The received light detection determination means 5 comprises a disturbance detection determination means 5a and a human body presence / absence detection determination means 5b.
The disturbance detection determining means 5a compares the output from the conversion circuit 4b of the light receiving means 4 with a reference value for disturbance determination that is predetermined inside, and the signal received by the light receiving means 4 indicates that there is disturbance. It is determined whether or not When the output from the conversion circuit 4b exceeds the reference value,
It is determined that the signal received by the light receiving means 4 indicates the presence of disturbance, and the disturbance detection signal is emitted as the light emission timing control means 8
(Detection number counting means 10 and timing control means 14 described later)
Is output to.

The human body presence / absence detection determination means 5b is the light receiving means 4
The output from the conversion circuit 4b is compared with a predetermined reference value for human body determination, and whether the signal received by the light receiving means 4 indicates the presence of a human body in the detection space E or not. Is being determined. Then, when the output from the conversion circuit 4b exceeds the reference value, it is determined that the signal received by the light receiving means 4 indicates the presence of the human body in the detection space E, and the human body presence signal is output to the output means 6. ing.

The reference value for the disturbance determination in the disturbance detection determination means 5a and the reference value for the human body determination in the human body presence / absence detection determination means 5b may be at the same level or different levels.

The output means 6 outputs a human body presence signal input from the human body presence / absence detection determination means 5b to the display means 7 or an external control device (not shown) when it is determined that a human body exists in the detection space E. is doing. For example, output this output signal to a CD
When inputting into 9, it is possible to start the operation guidance of the CD 9. Further, in an unmanned store where the CD corner is operated unattended, it can be used to judge the start of a store closing operation such as closing the shutter depending on the presence or absence of this signal in the automatic store opening / closing device.

The display means 7 is composed of a display such as a light emitting diode, a liquid crystal display or a fluorescent display tube, and based on a human body presence signal inputted from the output means 6, a display indicating that the human body is present in the detection space E. It is carried out.

Specifically, when the display means 7 is composed of a light emitting diode, when a human body presence signal is input from the output means 6, the light emitting diode is, for example, green to indicate that the human body is present in the detection space E. Lights up. Further, when the display means 7 is constituted by a display device such as a liquid crystal display or a fluorescent display tube, when a human body presence signal is input from the output means 6, a message indicating that a human body is present in the detection space E is displayed. .

The light emission timing control means 8 includes a detection number counting means 10, a detection number determining means 11, and a first time counting means 1.
2, a second timing means 13, a timing control means 14, and a drive control means 15 are provided.

The light emission timing control means 8 always controls the light emission drive by the light emitting means 3 at a predetermined time interval during the normal time when the disturbance is not detected. Further, the light emission timing control means 8 controls the light emission drive of the light emitting means 3 so as to delay or accelerate the light emission timing when the light receiving means 4 detects the disturbance and receives the disturbance detection signal from the light reception detection determining means 5. is doing.

The detection number counting means 10 is composed of, for example, a shift register, and counts the disturbance detection signal input from the disturbance detection determining means 5a immediately before the light emitting means 3 is driven to emit light from the stopped state, and counts the number of times. It is output to the detection number determination means 11 as disturbance detection data. The number of times counted by the detection number counting means 10 immediately before the light emitting means 3 emits light is reset to 0 after the light emitting means 3 is turned on.

The detection number judging means 11 judges whether the content of the disturbance detection data from the detection number counting means 10 indicates the detection number of 1 to 3 times, and outputs the judgment signal to the clock control means 14. Is output to.

The first clocking means 12 is composed of a timer circuit which counts a timer period T (for example, T = 50 msec) of a predetermined cycle in a state where no disturbance is detected. When the disturbance is detected immediately after the light emission means 3 emits light at the timer time T interval, the first time measurement means 12 shortens the time-up time to a predetermined time (for example, 40 msec) by the control of the time measurement control means 14 described later. Is set. The first clock means 12 outputs a time-up signal to the drive control means 15 every time the time is up.

The second timing means 13 is used for varying the waiting time until the first timing means 12 starts timing when a disturbance is detected, and the first timing means 12 is used. It is composed of a timer circuit that measures a shorter timer time interval. The time-up time in the second time measuring means 13 is variably set to a different time according to the number of times of disturbance detection under the control of the time measuring control means 14.

Specifically, when the disturbance is detected for the first time, the time t1 is set to 10 msec. Further, when the disturbance is detected for the second time, the time t2 =
It is set to a time delayed by 5 mesc. Then, the second timing means 13 outputs a time-up signal to the timing control means 14 every time the time is up.

The clocking control means 14 controls the start of clocking by the first clocking means 12 in response to a power-on signal when the power is turned on. Further, the time counting control means 14 measures the time by the respective time counting means 12, 13 so as to change the standby time of the first time counting means 12 according to the number of times of disturbance detection included in the determination signal from the detection number determination means 11. The start is controlled.

Explaining further, the timing control means 14 is
When the determination signal indicating the first detection is input from the detection number determination means 11, the second timing means 13 is activated to start and control the timing, and after the time t1 elapses, the first count is performed. The time counting means 12 is reset, and the time counting by the first time counting means 12 is controlled to start with a delay of time t1.

When the determination signal indicating the second detection is input from the detection number determination means 11, the second timing means 13 passes the time t1 and the time t2. First time measuring means 12 after time is up
Is reset, and the time counting by the first time counting means 12 is controlled to start with a delay of time t1 + t2.

Further, the timing control means 14 does not activate the second timing means 13 when the determination signal indicating the third detection is input from the detection number determination means 11, and the first timing means 12 has no waiting time. Keeps the timekeeping by.

Further, the timing control means 14 is provided when the disturbance detection signal is inputted from the disturbance detection determination means 5a immediately after the first timing means 12 emits light at the timer time T intervals.
The timer time T by the first clocking means 12 is a predetermined time T
The time counting by the first time counting means 12 is controlled to start so that the time is shortened to a (for example, 40 msec). Then, when the time-up time shortened by the first clocking means 12 is reached, the first clocking means 12 is reset and returned to the normal timer time T.

As described above, in the case of delaying the light emission control of the light emitting means 3, when the disturbance is detected by the first time measuring means 12 immediately before the light emission at the timer time interval T, the second time measuring means 13 measures the time. Is started, and the time counting of the first clocking means 12 is restarted by the time-up of the second clocking means 13.

On the other hand, when the light emission control of the light emitting means 3 is advanced, the timer time T by the first time measuring means 12 is set.
When the disturbance is detected immediately after the light emission at the interval, the time-up time of the first clocking means 12 is shortened and set. The time-up time is shortened only once when the disturbance detection signal is detected immediately after the light emission, and next time, the timer time T by the normal first time measuring means 12 is reset and returned.

The drive control means 15 normally outputs a drive signal to the drive circuit 3b of the light emitting means 3 at the timing of the time-up signal input at each timer time T by the first timing means 13 to output the light emitting element 3. It controls the light emission drive of.

Next, the operation of the object detector having the above structure will be described with reference to FIGS. FIG. 3 is a flowchart showing a light emission control operation in the object detector of the present invention, and FIG. 4 is a view showing a light emission state depending on the presence or absence of disturbance.

First, the operation when no disturbance occurs will be described. For example, as shown in FIG.
At the CD corners in which D9 are adjacently arranged side by side, the object detector 1 is so arranged that a partial area Ea of the detection space E overlaps.
Are installed on the ceiling above each CD 9. After the installation of the object detector 1 is completed, when the power is turned on and turned on (S1), the first clocking means 12 is activated to start clocking (S2). Then, the light receiving means 4 receives and receives the near infrared rays in the detection space E (S3).

Next, the disturbance detection determining means 5a compares the signal taken in from the light receiving means 4 with the reference value for disturbance determination. Then, if the signal from the light receiving unit 4 exceeds the reference value, it is determined that the signal from the light receiving unit 4 indicates the presence of disturbance (S4-YES), and the process proceeds to S16 described below.

On the other hand, if the signal from the light receiving means 4 does not exceed the reference value, it is determined that there is no disturbance (S4-N
O), the light emission means 3 is driven to emit light by the drive control means 15 (S5). Then, the detection number counting means 10 used in S16 described later is reset (S6).

The detection light is sent to the detection space E by the emission drive of the light emitting means 3, and the detection light is stably reflected in the detection space E and can be received (for example, 2 ms).
When ec) has elapsed (S7-YES), the light receiving means 4 receives and captures the near infrared light in the detection space E (S8),
The drive control means 15 stops the light emission drive of the light emitting means 3 (S9).

Next, the human body presence / absence detection determination means 5b compares the signal received from the light receiving means 4 with the reference value for human body determination. Then, if the signal from the light receiving means 4 exceeds the reference value, it is determined that the signal from the light receiving means 4 indicates the presence of the human body (S10-YES), and the presence of the human body is displayed on the display means 7 of the object detector 1. The display output is performed or a signal indicating the presence of a human body is output to an external control device (S20).

Next, immediately after the light emission driving by the light emitting means 3 is stopped, when a time (for example, 2 msec) when the influence of the detection light by the light emitting means 3 disappears (S11-YES),
The disturbance detection determination means 5a compares the signal received from the light receiving means 4 in S12 with the reference value for the disturbance determination. Then, if the signal from the light receiving means 4 exceeds the reference value, it is determined that the signal from the light receiving means 4 indicates disturbance (S).
13-YES), and proceeds to the process of S21 described later.

On the other hand, if the signal from the light receiving means 4 does not exceed the reference value, it is determined that there is no disturbance (S13-
NO), when the timer time T = 50 msec, which is the time-up time of the first timekeeping means 12 in the normal time, has elapsed (S14-YES), the timekeeping control means 14 resets the first timekeeping means 12 (S15), Return to S2.

Thus, when no disturbance is detected,
As shown in FIG. 4A, light emission / stop of the light emitting means 3 is repeated every timer time T = 50 msec of the first clocking means 12.

Next, the operation when the disturbance is detected immediately before the light emission of the light emitting means 3 and the light emission timing is delayed will be described.

In the process of the disturbance detection determining means 5a in S4, if the signal from the light receiving means 4 exceeds the reference value and it is determined that the signal from the light receiving means 4 indicates the presence of disturbance (S).
4-YES), and proceeds to S16. At this time, the timing control means 14 sets the time-up time of the second timing means 13 and variably controls the waiting time of the first timing means 12 according to the number of times the disturbance is detected immediately before the light emission means 3 emits light. ing.

That is, when the detection number counting means 10 counts the first disturbance detection signal, the second time counting means 13 is t.
The time is up at 1 = 10 msec, after which the first clocking means 12 is reset and the process returns to S2. When the detection number counting means 10 counts the disturbance detection signal for the second time, the second timing means 13 is further timed up with a delay of t2 = 5 msec, after which the first timing means 12 is reset and S2. Return to.

When the detection number counting means 10 counts the disturbance detection signal for the third time, the first time counting means 12 continues the time measurement by the first time counting means 12 without waiting, and the first time counting means 12 continues to emit light. The process proceeds to the light emitting operation (S5).

As described above, the standby time of the first timing means 12 is changed depending on the number of continuous disturbance detections when the disturbance does not occur at a predetermined time interval or when the emission timing is shifted depending on the intensity of the disturbance. May be different.

When a disturbance is detected immediately before the light emitting means 3 emits light, as shown in FIG. 4 (b), the timer time T of the first time measuring means 12 is T = 50 msec and t1 = 10 m.
After the waiting time of sec has elapsed, the light emitting means 3 emits light in the next cycle.

When the disturbance is detected twice consecutively immediately before the light emitting means 3 emits light, as shown in FIG. 4C, the timer time T = 50 msec of the first clocking means 12 is compared with t1. = In addition to the waiting time of 10 msec, t2 =
After the waiting time of 5 msec has elapsed, the light emitting means 3 emits light in the next cycle.

Further, when the disturbance is continuously detected three times immediately before the light emitting means 3 emits light, the light emitting means 3 emits light without waiting time as shown in FIG. 4 (d).

Next, the operation of detecting the disturbance immediately after the light emission of the light emitting means 3 and advancing the light emission timing will be described.

In the processing of the disturbance detection determining means 5a in S13, when the signal from the light receiving means 4 exceeds the reference value and it is determined that the signal from the light receiving means 4 indicates the presence of disturbance (S13-YES), the process proceeds to S21. Transition. In S21,
By the control of the time counting control means 14, the time-up time of the timer time T = 50 msec by the first time counting means 12 is set to be shortened to the predetermined time Ta = 40 msec, and when the mimer time Ta has elapsed, the first time counting means 12 is set. And time up time T = 50ms
Set to ec and return to S2.

As described above, when the disturbance is detected immediately after the light emitting means 3 emits light, the timer time is shortened from T = 50 msec in S14 to Ta = 40 msec as shown in FIG. Is emitted.

Therefore, according to the above-described embodiment, the object detectors 1 that emit the detection light into the detection space E at regular time intervals can be installed at positions where they interfere with each other. For example, as shown in FIG. 2, even when a plurality of CDs 9 are arranged close to each other in a CD corner of a financial institution formed in a limited space, the area where the user is present when using the CDs 9 is detected as a detection space. It is possible to install the object detector 1 for each CD so that the area Ea of the detection space E overlaps with each other. Further, since the object detector 1 can be installed by overlapping the partial area Ea of the detection space E in this manner, the object detector already installed is not taken into consideration, and the object detector 1 can be easily installed later. An object detector can be added to the and the load on the mounting work can be reduced.

Further, even if the object detector 1 is installed in an environment where a disturbance is periodically generated, the light emission timing of the light emitting means 3 is either before or after the time-up time of the timer time T by the first timing means 12. Since it can be shifted to, the influence of noise can be avoided and malfunction can be prevented.

Further, even if the environment surrounding the object detector 1 changes, the light emission timing of the light emitting element 3 can be automatically changed and shifted, so that the worker can go to the installation place to change the light emission timing. Can be saved.

By the way, the object detector 1 having the above-mentioned configuration is not limited to the one arranged for each CD 9 in the CD corner of the financial institution as shown in FIG. 2, but can be applied to other technical fields. . For example, it can be used as an object detector for detecting the presence or absence of an object conveyed on a belt conveyor in a manufacturing factory line.

Further, in the above embodiment, the light emission timing of the light emitting element 3 in the next cycle is delayed only when the disturbance is detected once or twice in succession immediately before the light emitting means 3 emits light. As described above, only when the disturbance is detected once, or when the disturbance is continuously detected three times or more, the light emission of the light emitting element 3 is driven so as to delay the light emission timing of the light emitting element 3 in the next cycle. You may control. If disturbance is detected multiple times in succession,
The standby time based on the second time count time 13 is, for example, 10 msec when the number of times of disturbance detection is the first, 5 msec when the second time is detected, 3 msec when the third time is detected, and 1 msec when the fourth time is detected. The length is set to be gradually shorter according to the number of detections.

[0071]

As is apparent from the above description, according to the present invention, the object detectors that emit the detection light into the detection space at a constant time interval can be installed at positions where they interfere with each other. Therefore, it is possible to easily add the object detector by retrofitting. Further, even if the light emitting device is installed in an environment where a disturbance is periodically generated, the light emission timing can be shifted to either the front or the rear, so that the influence of noise can be avoided and a malfunction can be prevented. Further, even if the environment surrounding the object detector changes, the light emission timing can be automatically shifted, so that it is possible for the worker to save the trouble of going to the installation place and changing the light emission timing.

[Brief description of drawings]

FIG. 1 is a block configuration diagram showing an embodiment of an object detector according to the present invention.

FIG. 2 is a diagram showing an example of an installation state of the object detector.

FIG. 3 is a flowchart showing a light emission control operation in the object detector.

4A is a diagram showing a light emission timing when there is no disturbance in the object detector, and FIG. 4B is a diagram showing a light emission timing when one disturbance is detected immediately before light emission in the object detector. ) A diagram showing a light emission timing when two disturbances are continuously detected immediately before light emission in the same object detector (d) A light emission timing when three disturbances are continuously detected immediately before light emission in the same object detector The figure (e) The figure which shows the light emission timing when a disturbance is detected immediately after light emission in the same object detector.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Object detector, 3 ... Light emission means, 4 ... Light reception means, 5 ... Light reception detection determination means, 5a ... Disturbance detection determination means, 5b ... Human body presence / absence detection determination means, 8 ... Light emission timing control means, 10
... Detection number counting means, 11 ... Detection number determining means, 12 ...
1st timing means, 13 ... 2nd timing means, 14 ... Timing control means, 15 ... Drive control means, E ... Detection space.

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H03K 17/78 G01S 17/02

Claims (3)

(57) [Claims] 1. A light emitting unit that emits detection light in a detection space at a predetermined time interval in normal times, a light receiving unit that receives reflected light from the detection space, and the light receiving unit when emitting the detection light. an object determining means for determining presence or absence of an object based on the amount of light received, the disturbance determining means determines the presence or absence of disturbance on the basis of the received light amount of said light receiving means definitive before emission of the detection light, the light emission disturbance determination means The ambient light is detected immediately before the emission of the means.
The light emission timing of the light emitting means when it is determined that the light is emitted
And a light emission timing control means for delaying the light emission at different times according to the number of times of disturbance detection. 2. A light emitting unit that emits detection light in a detection space at a predetermined time interval during normal times, a light receiving unit that receives reflected light from the detection space, and the light receiving unit when emitting the detection light. an object determining means for determining presence or absence of an object based on the amount of light received, and the disturbance determining means for determining whether a disturbance on the basis of the received light amount of said light receiving means after light emission of the detection light, disturbance decision means the emission The ambient light is detected immediately after the emission of the means.
The light emission timing of the light emitting means when it is determined that the light is emitted
And a light emission timing control means for accelerating the light emission. 3. Normally, the detection space is set at a predetermined time interval.
A light emitting unit that emits detection light, a light receiving unit that receives reflected light from the detection space, and a light receiving amount of the light receiving unit when the detection light is emitted.
Of the light receiving means before or after the detection light is emitted.
Disturbance determining means for determining the presence or absence of disturbance based on the amount of received light, and the disturbance determining means detects the disturbance light immediately before the light emitting means emits light.
When it is determined that the light is emitted, the light emitting timing of the light emitting means
Delay the delay at different times depending on the number of disturbance detections.
That is, the disturbance determining means causes the disturbance immediately after the light emitting means emits light.
When it is determined that light is detected, the light-emitting
Equipped with a light emission timing control means for accelerating the aiming
An object detector characterized in that