Some readers may recall building a line-following robot ... uses a whopping 32 IR sensors to follow a black line across a concrete workshop floor, adjusting its path using a steering motor ...

This time around he’s bent the IR emitter and receiver downward to use as a reflectance sensor. This gives it the ability to follow a dark line on a light surface.

In this article, we implement a rain and ice sensor by ... as a counter using the internal clock at 25 kHz (configured in OSC). CNT2 provides the 10-μs HIGH level pulse. IR LED emitter driver ...

Personally, I use them in closets ... discs can be placed in a line to create the look of a vanity, or on their own for extra light in drawers. Lightbiz LED Motion Sensor Light ($25.99 for pack ...