Who knows the jamming principle of outdoor visible light jamming infrared receiver?

The full name of infrared beam detector is photoelectric beam detector, and its basic structure includes aiming hole, beam intensity indicator, spherical lens, LED indicator and so on. The detection principle is that infrared light is transmitted to a long distance through LED infrared light emitting diode, and then focused by optical reflector and received by receiver. When the light is blocked, an alarm will be given. Infrared ray is a kind of invisible light, which will spread to form a cone beam when projected. Infrared light emits 1000 beams per second, so it is a pulsating infrared beam. Therefore, these opposites cannot be transmitted over a long distance (within 600 meters).

When someone crosses the monitoring protection zone, the detector using beam blocking method will block the invisible infrared beam and trigger an alarm. Often used for outdoor fence alarm, always used in pairs: one transmitting and one receiving. The emitter emits one or more infrared rays invisible to human eyes, forming a warning line. When an object passes by, the light is blocked, the receiver signal changes, and an alarm will be given after amplification. The infrared crosstalk probe should choose the appropriate response time: too short is easy to cause unnecessary interference, such as birds flying by and small animals passing by; If it is too long, it will not be able to report. The shortest shading time is usually determined at the speed of10 m/s. If the width of a person is 20cm, the shortest interruption time is 20 ms.. More than 20ms alarm, less than 20ms no alarm.

At present, there are two, three and four active infrared detectors with ranges ranging from 30 meters to 250 meters, and some manufacturers produce long-distance multi-beam "light walls", which are mainly used in factories and mines and some special places.

Advantages of infrared correlation in perimeter defense;

1, covert defense mode: let intruders contact the police unconsciously.

2. Comprehensive fortification around: there are no blind spots and dead corners.

3. Complete defense capability: The intruder cannot pass through the defense range of the invisible infrared defense beam network by jumping, lying down or other actions.

4. Good anti-interference characteristics: When insects or small animals pass through the infrared defense beam network, because the infrared defense beam cannot be completely blocked, there will be no false alarm.

5. Strict anti-sabotage ability: When the power cord or signal line of the infrared receiver is cut off, the alarm signal output circuit will automatically output wireless alarm signals.

6. You can work all day. Anti-interference ability of infrared radiation detector to bad weather environment.

Infrared fence

First, the working principle of infrared fence:

Infrared fence (also called "infrared railing") is an active infrared radiation. It uses multiple infrared rays to shoot at each other. The transmitter emits infrared light to the receiver in the way of "low frequency emission and time division detection". Once someone or an object blocks any two adjacent beams of light emitted by the transmitter for more than 30ms, the receiver immediately outputs an alarm signal. When small animals or objects block one of the beams of light, the alarm will not output an alarm signal.

Second, the advantages of infrared fence:

Low frequency infrared emission: no interference to household appliances (remote control system);

Intelligent light intensity detection: reduce power consumption and false alarm;

A variety of installation methods: surface-mounted and embedded installation can be used without accurate alignment;

Cross infrared correlation: completely avoid direct sunlight interference (unique technology);

Pursuing the perfect combination with modern family decoration.

Third, the application of infrared fence:

Infrared fence is the front-end product of new family security window and balcony, which replaces Lacan cage, door and window magnetic switch, curtain detector and other products used in traditional technical defense, and forms a powerful anti-theft alarm system with various anti-theft alarm controllers. According to its working principle, it can also be extended to a variety of uses, such as vehicle detection at the entrance and exit of indoor parking lots.