MCU Examples.com
PIC Microcontroller Project Examples, free source codes and resources collection.
Infrared Sensors
An infrared sensor is a device that is capable of emitting or receiving infrared waves in the form of heat. While the vast majority of infrared sensors transmit and receive infrared waves, some infrared sensors are only able to receive them. These types of infrared sensors are known as passive infrared sensors, or PIR sensors, and are usually found in the form of motion detectors.
How Infrared Sensors Work
All infrared sensors are dependent on pyro-electric materials, which produce an electrical voltage whenever it is heated or cooled. Most infrared sensors are coated with either parabolic mirrors or Fresnel lenses in order to retrieve infrared waves from an entire room or area. As infrared waves reach the sensor from different areas, they cause the sensor to generate a voltage in different waves and can be used to trigger an alarm or activate another type of system.
Applications
Infrared sensors can be used in a number of applications but usually involve
measuring distance,
detecting motion, or transferring data
In televisions and motion detectors, with televisions being activated by an infrared remote
and motion detectors being, naturally, activated by motion.
Used in heat-seeking missile in order to detect their target.
Advantages
Infrared sensors are advantageous because
They operate by using a type of electromagnetic wave
That is invisible to human eyes, harmless to users, and is naturally emitted by all objects.
Relatively inexpensive
Provide the most efficient method of detecting objects, especially while they are moving.
Simple in design and provide a reliable method of detection.
Small in size and can be installed into virtually any electronic device. (infrared remote)
