WWZMDiB 6Pcs IR Infrared Sensor 3-Wire Reflective Photoelectric Module for Arduino

Works well

Super cheap for the amount of sensors provided. They work superbly, detecting black and white like a charm. The wires that come with the sensors are also very high quality and super handy.

I bought these to sense trains passing by in my model railroad setup. All six modules work fine, I even dropped a couple of them on the floor a few times from about 3' and they survived. (Not recommending it.) After reading reviews on other modules that look similar to these, I ended up running them at 3.3V and haven't experienced any problems so far. For my needs I had to desolder both the detector and emitter from the circuit board and extend them with 6" wires. Even with this untypical installation, the modules performed as advertised. The adjustment pot seems to only work about half of its movable range, once you turn it about 50% it seems to stay in the detecting state, so you might lose a little precision in fine adjustments. It worked well enough for my purposes, but it would have been nice to have the full range which is only about 3/4 of a full-turn the way it is. In case you are wondering they acted this way before I made my modifications, so adding the length of wire did not change this characteristic. The Dupont connectors are what they are, fairly flimsy but do the job adequately for setup and testing in a breadboard. I wouldn't necessarily recommend using them in a permanent installation like mine. I custom made my own wires for my needs.

Easy to integrate into your setup, outputs a straightforward hi/low signal for digital I/O. Sensing distance is consistent, but as noted in the description can be impacted especially when the surface being reflected off of is black or otherwise absorbs the IR light. In that case, the sensor will not trigger and you'd be better served with a different technology - not a defect of this component - just a shortcoming of the specific sensor technique.

Great for hobbiests and tinkering. I had one that was inconsistant but all the others worked as intended.