he IR obstacle detection sensor from Robot Base is designed for robust operation.  Using a modulated LED light source of 40Khz, and a sensitive tuned IR receiver, the module effectively discriminates against most indoor light sources.  The board supports an adjustable gain potentiometer, as well as an adjustable threshold potentiometer.  The sensor module outputs a logic high if no obstacle is detected, and outputs a logic low if an obstacle is detected.  A convenient LED is supported which provides an immediate status of the sensor. 

The detection range of the IR sensor is between 2-40cm, with an operating voltage of 3.5-5V. The IR detector is compatible with most Arduino Boards as well as several other microcontrollers.  See datasheet for more details of this exciting sensor product.