Alignment lasers are typically eye-safe and feature low optical powers. When used over long distances the small diameter laser beams diverge heavily creating a very large spot on the target. This large, low power laser spot is almost invisible to the naked eye, especially during the daytime.
To overcome this issue the beam is expanded to 16mm and then can be focused at long distances thanks to its low 0.07mrad divergence. Combined with the green 520nm laser, the FP-LR module can produce laser spots as small as 5.5mm over distances of 500m, which are visible in daylight conditions, and if used under dark conditions the laser beam can be focused up to 200m.
