The processor uses 51 series single

The processor uses 51 series single chip 89C51. The whole system works under the control of system software. The infrared probe set at the monitoring point converts the infrared spectrum of human body radiation into electrical signal, and amplifies and compares the circuits.

When the infrared thermoelectric sensor reaches the infrared radiation source, the temperature of the internal sensitive material increases, the electrode decreases and the surface charge decreases.

The number of thermal charges can reflect the change of material temperature, and the output voltage of circuit conversion can also reflect the change of material temperature, so as to measure the change of infrared energy. Radiation. The optical system of the infrared detector focuses the energy of infrared radiation in many directions of the detector.

When there is no moving human body in the reserve, the alarm cannot be triggered, because the infrared radiation energy of all background objects (such as walls, furniture, etc.) is relatively small and stable at room temperature. When the human body suddenly enters the detection area, it will cause the sudden change of infrared radiation energy. Infrared detector transforms the infrared radiation energy change between moving human body and background object into corresponding electric signal and electric signal. According to the temperature change speed of the sensor, the comparator and the state controller generate the corresponding output signal U, and send it to the alarm device to send out the alarm signal. The detection wavelength of the infrared detector is 8-14 microns, and the infrared radiation wavelength of the human body is in this range.

This can detect changes in the infrared energy radiated by humans and contact them and convert them into voltage signals. Expanded voltage signals can activate multiple control circuits.