An infrared line follower!
We highly recommend that you purchase these sensors in pairs! Therefore you place one sensor either side of the line you want to follow. Sensors are low, and go high when they see a white surface. If it detect reflective surface it goes high.
Based on the TCRT5000 these sensors consist of a pair of reflective sensors which include an infrared emitter and phototransistor. The sensors can be used for line/track following and obstacle avoidance in robots!
Features & Specification