A PIR (Passive InfraRed) Passive Infrared is an electronic device that measures the infrared light emitted by objects in a given field of view. apparent motion is detected when an infrared source with a temperature, such as the human body passes in front of an infrared source with another temperature as a wall.
Every object emits what is known as black body radiation this energy is invisible to the human body but can be detected by electronic devices designated for such purpose. The term passive means that the PIR does not emit energy of any type, but passively accepts input from infrared radiation.
Components of a PIR-Lens
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pyroelectric sensor-amplifier circuitry
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-Chip Detection
Lens The lens is composed of many small lenses are called lenslets each lenslet focuses
infrared energy to the pyroelectric sensor
c ada energy focus of each lenslet is referred to as "zone"
pyroelectric sensor / Amplifier
2mm 2 items
positive -1, 1
-negative elements create two areas within a zone
If you enter in the positive zone, there is a positive charge, if you enter a negative zone , there is a negative charge. The two charges
combine to produce an output.
this result goes through an amplifier that is connected to the elements increasing it.
detection circuitry / Microcontroller
This circuitry is analyzing the amplified signals to determine if an intruder is present.
The analysis software is within the microcontroller.
The microcontroller has low power consumption
How Do Components?
6 / 2 are used for more accurate detection:
-filtering-thresholds
-Signal Analysis of Amplitude-Analysis
Time - Frequency Compensation
-Compensation
Temperature
unfinished post ............
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