How far can the green laser light?

In today’s society, the compact and easy-to-use green laser pen is used as a guide. The light source has been widely used in conferences, teaching, museum visits, mountain climbing, and construction. There are many places such as physical inspection, military command, help, astronomy, etc., in all parts of the world.There is a very large market sales volume. The main core structure of the green laser pen is a miniature solid laser pumped by a laser diode (Laser Diode or LD). Currently, using.The most common crystal for making green laser pointers is the combination module of Nd: YV0 4+KTiOP0 4(KTP). The Nd: YV0 4 crystal produces 1064nm near-infrared laser, and the KTP crystal converts 1064nm laser into cavity through frequency doubling. 532nm green visible light output, the inner light-passing end faces of the two crystals are glued (or photoglue) together, and the light-passing end faces are plated with a dielectric film (such as Nd: YV04 The outer end face of the crystal is plated with 808nm anti-reflection and 1064nm, 532nm anti-reflection coating near the pump source end, and the KTP crystal's outer end face is plated with 808nm, 1064nm high-reflection and 532nm anti-reflection coating away from the pump source end) to form the fundamental frequency Resonant cavity for light oscillation and green light output.