The principle of reflective clothing

Reflective materials are produced by optical refractive index directed regression using glass microspheres or microprism materials. Basically, it is possible to return the direct light from a distant place to the same effect as the light. But if there is no source of light, then there is no luminous effect, because it does not emit light by itself. So many people who don’t understand at night see that the clothes don’t shine. It’s a misunderstanding. The reflective material must work in the presence of a light source.