Sharp Proximity Detector IS417F
Infrared light sensor with built in pulse driver circuit and sync detector.
Useful as a short-range wide-angle proximity detector or for non-contact bump sensing.
The pulse driver modulates the output of an external infrared LED (not included).
The LED will illuminate the target with modulated IR; reflected IR in sync with the output is detected by the IS471F, making detection relatively insensitive to ambient lighting.