As a sensor detection device, the detector is used to detect the invasion behavior of intruders and various abnormal situations. There are many places that need security precautions in various smart buildings and ordinary buildings. These places also have a variety of safety purposes and requirements according to the actual situation.Therefore, a variety of alarm detectors are needed to meet different safety requirements.
In the burglar alarm field, infrared detection technology is one of the most widely used. There are active infrared detectors and passive infrared detectors.
Active infrared detectors are more applied on the outside wall fence or the outside of the building Windows protection. And generally it is with passive infrared detectors direction recognition technology together, used for protection of buildings, such as residential balcony door. The technology can automatically determine whether the user passes through the defense area from the inside and returns from the outside or enters the room directly from the outside. If users passes through from indoor to outdoor, it will not alarm. Otherwise, it will alarm. And it also gives an allowed return time without alarm. Over the return time, it is back to arm status. So, it makes the perimeter prevention more humanized.
Infrared detection medium has good anti-interference for the environment sound, lightning, vibration, all kinds of artificial light source and electromagnetic interference source. Only when the infrared beam is blocked, the alarm will be triggered. So the active infrared intrusion detector is widely applied for perimeter security protection.
Active intrusion detection of infrared technology products are: traditional active infrared intrusion detector, frequency discrimination type of active infrared intrusion detector, infrared curtain wall, which are respectively applied to the analog pulse modulation, multi-frequency point pulse modulation, pulse modulation based on the code modulation. The difference is that the products have different prevention heights. The first two types of active infrared intrusion detectors have low (about 30 cm) prevention height and clear single-direction prevention direction. The infrared wall protection height can reach to 2 meters or higher, which can realize both sides intrusion and defense direction is hidden.
Active infrared detector technology mainly adopts infrared light transmitting and receiving, which belongs to linear prevention.The transmitter of the active infrared detector sends out a modulated infrared beam, which is received by the infrared receiver, thus forming a warning line consisting of an infrared beam.When encountered leaves, rain, small animals, snow, dust, fog cover will produce a false alarm. Now the active infrared detector has been developed from the original single beam to multi-beam, using multi-frequency point transmission, frequency conversion transmission and other technologies, to minimize the false alarm rate, so as to enhance the stability and reliability of the product.
The application of solar wireless infrared detector technology is a new starting point of detector development. Solar infrared detector has built-in rechargeable lithium battery, and the power is supplied by solar panels, and the energy consumption is very low. Even in rainy weather, it can be used normally with the stored power for 20 days. In this way, solar energy can be recycled without laying power cables.Generally speaking, solar panels are amorphous silicon and do not require direct sunlight to generate electricity.In addition, solar panels can provide much more power than they consume in light, allowing them to operate without light at night and in continuous rainy weather.
Solar infrared beam, solar infrared fence and solar infrared wall make good use of solar power supply and wireless transmission, and become all wireless active infrared beam perimeter protection products. It solved the troubles of construction and maintenance of active infrared beam system.