“Ir sensor used to dectect any movement made in front of the two sensors which is IR led and photodiode.
The range of Ir sensor can be adjusted using variable resistor(preset) . the range depends on Quality and specification of Ir led and Photodiode used.
Ir sensor can be used for making hobby projects like Line follower robot without using a microcontroller, obctable detector robot or obstacle avoider robot.
Ir sensor can also be used for home automation like automatic water dispenser, automatic sliding door,automatic sliding door.
Since it has wide range of applications it can also be used for security purpose for detecting trespassing and you can create your own applications too.”