Some solutions to the ambient light issue
As we have repeatedly emphasized, this module is very sensitive to ambient light, so it is necessary to take some measures to block the ambient light. Here are some of our buyers' solutions that effectively block ambient light interference to make the module work well. We thank them for sharing!
1.Use a black plastic project enclosure Sensitivity is high, so it is necessary to block off ambient light or it will be overwhelmed by ordinary room light. I used a black plastic project enclosure with a small hole drilled in the end. Placing the module inside the box, moving the sensor some distance from the hole attenuates ambient light reaching the sensor. This sets Day/Night threshold, and prevents stray light triggering. A Laser light beam projected through the hole triggers the sensor quite well regardless of internal distance.
2.With a black straw They do get triggered by sunlight/incandescent/and many others (just cuz sunlight et al have plenty of 650nm light).But if you properly cover it (like with a black straw) it works just great.
3. Put sensor on the back to point the other way. They are sensitive to visible light.
4.A small 3D printed enclosure One important point that I took for granted is that I mounted these in a small 3D printed enclosure that only allows light directly in the front. That obviously helps with the ambient light issue.