"Detecting was possible without lens." "should I have unconditional cap?"
Many people say and ask like this, so I will show you why you have to use fresnel lens for PIR(Sensor Cap) through a short movie.
Not to mention that the modules in this movie are dealt with byDIYPRO, and sensors have high specifacation including quad element (NiCERA), not dual.
(You can find the specifications of fresnel lens at the end of this movie. If you want to check this, you should increase the resolution of the video.)
Question for motion detection sensor, PIR sensor, module
Myung Joong KIM