Eyeglasses mainly prevent laser damage to eyes. Because the laser energy is highly concentrated, it is very harmful to the eyes and even has the risk of blinding, so laser workers must wear laser protective glasses. Laser protective glasses mainly include absorption type, reflection type, compound type, explosive type, photochemical reaction type, glass-ceramic type and so on.
Absorption is to add various absorbers to glass or plastic lenses to absorb laser light and make it impenetrable. The reflection type is to plate a group of high refractive index dielectric films on the lens. When the light hits the dielectric film, the phase of all the reflected light on the interface is the same, so that the reflection of light at this wavelength is strengthened, which can reflect the laser to protect the glasses The purpose is to have a high transmission capacity for other visible light.
The compound consists of two reflective dielectric films, separated by a layer of color-absorbing glass in the middle to suppress unwanted internal reflection between the two reflective films. This kind of glasses has a better protection performance for lasers and a large safety factor, which is suitable for the protection of large and medium power lasers.
Explosive type is to coat a layer of explosives on the lens. When the incident laser intensity reaches a certain value, it quickly detonates to shield the laser and is used in the military to prevent laser weapons from injuring the eyes. Each type of laser safety glasses has its own characteristics. Generally, it can only prevent one wavelength of laser light, and a few can prevent two or more wavelengths of laser light. Therefore, you must choose the appropriate laser goggles according to the laser used.