Understanding Passive infrared sensors (PIR Sensor)

You've probably used an infrared (IR) sensor, whether you realize it or not. Most of us have changed the channel on the television using an infrared (IR) remote control, and many of us have walked past security sensors that detect movement using IR radiation. IR sensors are widely used by manufacturers, and you've probably seen them in action on automated garage doors. An emitter is a standard IR sensor fires invisible light at a receiver located some distance away. If the signal is not picked up by the receiver, the sensor indicates that an object is in its path. What Does PIR Stand For? A passive infrared (PIR) sensor is a type of electronic sensor that measures the amount of infrared (IR) light emitted by objects in its field of view. They're most commonly found in PIR-based motion detectors. PIR sensors are commonly used in security alarms and automatic lighting applications. PIR sensors detect general movement but do not provide information about who or what moved. An imaging infrared sensor is required for this purpose. PIR sensors are commonly referred to as "PIR" or "PID," which stands for "passive infrared detector." The term passive refers to the fact that PIR devices do not emit energy for detection purposes. They operate entirely by detecting infrared (radiant heat) emitted or reflected from objects. PIR Sensor Functions To begin, recognize that all humans, animals, and even inanimate objects emit some IR radiation. The amount of IR radiation they emit is proportional to the body's or object's warmth and material composition. Humans cannot see infrared radiation, but we have developed electronic detection devices to detect it. Thermal sensing applications such as security and motion detection use PIR sensors. They are frequently employed in security alarms, motion detection alarms, and automatic lighting applications. How Do PIR Sensors Work? Passive infrared (PIR) sensors detect heat energy in their surroundings using a pair of pyroelectric sensors. These two sensors are placed next to each other, and when the signal differential between the two sensors changes (for example, if a person enters the room), the sensor will engage. That could mean it sounds an alarm, notifies authorities, or turns on a floodlight. Using a series of lenses built into the sensor's housing, IR radiation is focused on each of the two pyroelectric sensors. These lenses increase the sensing area of the device. Read more:https://robocraze.com/products/hcsr501-pir-motion-sensor-passive-infrared-sensor