So, with just two cheap modules, you can build a laser proximity sensor—whether it is the thru-beam type or the reflective type. But I will not go into the build ideas as there are countless tutorials ...

The sensor shown here is essentially two plates mounted side-by-side, attached to an Arduino Nano using the Capacitor library which uses just two pins, one digital and one analog.

This tiny proximity sensor looks like a nifty chip, providing distance measurements up to 200 mm and an ambient light sensor in one package. The routing table has an LCD display and buttons, ...

I recently had to build an infrared close proximity sensor that could tell if something was dropped in a parcel delivery drop box. After some searching, I ended up using a microcontroller and a piece ...