This Infrared IR Distance Sensor has a range of 10 to 80cm. It is an easy to use Distance or Proximity Sensor which uses infrared lights to measure distance or proximity rather than ultrasonic sounds like the Ultrasonic Sensor. The connection to the Arduino is very easy, only need Power, Ground and Analog Input pin. Check out the example link below.
Features / Specifications
Infrared Distance (Proximity) Sensor – Sharp GP2Y0A21YK0F (10 to 80 cm)
Tutorials / Manuals / Documents