Even when I shot it 10m in front, it didn't collect any light at all and produced a 10cm won. A closer look at the beam reveals that the focus is 10cm in front of the laser designator and diffuses behind it. The focal point is too far forward, and the farther it is, the more the light travels, so if you use a concave lens to move the focal point a little further it seems to work fine. Low power laser pointer (power less than 0.4MW). In any case, the MPE values of the eyes and skin will not be exceeded even after the optical system is focused. It is safe to a certain extent and does not require special attention. This type is mainly used for geological exploration equipment, laboratory analyzers, short distance communication and transmission. The power is less than 0.4MW, harmless to the eyes.
I couldn't get a concave lens with a diameter of about 10 mm that I could fit in front of the laser designator. The smallest concave lens on the market has a diameter of 30 mm. I shaved so many lenses. Since the lenses are not glass, they can be fabricated or easily finished, and the light travels just right, shooting the lenses left in the house forward. Laser Pointers are known for their common demonstration and astronomical uses. Do you remember when you were a kid you could easily buy lasers in stationery? Laser Pointers come in blues, yellows and purples as well as the usual reds and greens. Depending on the color, these different Laser Pointer can be expensive.