Glasses mainly prevent laser damage to the eyes. Because the laser energy is highly concentrated, it is very harmful to the eyes, and even has the risk of blindness, so laser operators must wear laser-protective glasses.
Laser protective glasses mainly include absorption type, reflection type, composite type, explosive type, photochemical reaction type, glass-ceramic type, and other types.
The absorption type is to add various absorbers to the glass or plastic lens to absorb the laser light so that it cannot pass through.
The reflective type is to coat a group of high-refractive-index dielectric films on the lens. When the light hits the dielectric film, all the reflected light phases on the interface are the same, so that the light reflection of this wavelength is strengthened, which can not only reflect the laser light to protect the glasses It also has high transmittance to other visible light.
The composite type consists of two reflective medium films separated by a layer of color-absorbing glass to suppress unwanted internal reflections between the two reflective films. This kind of glass has better protection performance than lasers and has a large safety factor, and is suitable for the protection of large and medium-power lasers.
The explosive type is to coat a layer of explosives on the lens. When the incident laser intensity reaches a certain value, it will be detonated quickly to play the role of shielding the laser, and it is used in the military to prevent laser weapons from harming the eyes. Each type of laser-protective goggle has its characteristics. Generally, it can only prevent lasers of one wavelength, and a few can prevent lasers of two or more wavelengths. Therefore, appropriate laser goggles must be selected according to the laser used.