With its outstanding performance such as rapidity, accuracy and safety, laser rangefinders gradually replace tape measure in more and more fields. Laser rangefinders, as the name suggests, use lasers as the main working substance to work. At present, the working materials of the handheld laser rangefinders on the market mainly include the following: semiconductor lasers with working wavelengths of 905 nanometers and 1540 nanometers, and YAG lasers with working wavelengths of 1064 nanometers. The wavelength of 1064 nanometers is harmful to human skin and eyes, especially if the eyes are accidentally exposed to the laser of 1064 nanometers, the damage to the eyes may be permanent. Therefore, when purchasing a laser rangefinder, there are "safe" and "unsafe" points.
