TCRT5000L IR Reflectance Sensor (2.5mm)
This IR reflective sensor utilizes a TCRT5000 to detect color and distance. This sensor is often used in line following robots, because this module can sense if a surface is white or black. The measuring distance range range from 1mm to 8mm, where the central point is set to 2.5mm. There is also an on-board potentiometer to adjust the sensitivity.