At What Laser Wavelength Do You Need Safety Glasses?

When using lasers, eye protection is not optional, but crucial. Whether in industrial processing, scientific research, or medical applications, understanding which laser wavelengths require safety glasses can effectively prevent irreversible eye damage.

1. Why are laser safety glasses crucial for eye safety?

Laser wavelength determines how light interacts with the eye and tissues. Different wavelengths penetrate and damage the eye in different ways:

①Ultraviolet lasers (100-400nm) typically damage the cornea and lens, leading to photokeratitis or cataracts.

②Laser wavelengths in the 400-1400nm range can directly penetrate the lens of the eye, damaging the retina and even the optic nerve, causing irreversible damage. Visible lasers (400-780nm) pose the greatest threat to the retina because they are directly focused on it; near-infrared lasers (780-1400nm), although invisible to the naked eye, are also extremely harmful because the eye cannot blink or naturally avoid them. 

③Lasers in the wavelength range above 1400nm and ultraviolet lasers cause similar damage to the human eye, primarily affecting the cornea and lens. Mid- and far-infrared lasers above 1400nm can cause heating and burns to the corneal or lens surface.

Even low-power lasers can cause serious damage if the beam or reflected light enters the eye, especially in the visible or near-infrared range.

2. When Should You Wear Laser Protective Glasses?

You should wear laser safety glasses in the following situations:

①When you are operating or near a working laser source (even during calibration or testing).

②When the laser power exceeds the Class 1 laser limit (typically Class 2, 3, or 4 lasers).

③When you are exposed to invisible laser radiation, such as infrared or ultraviolet light.

For example:

532 nm (green) and 650 nm (red) lasers require glasses with the corresponding optical density (OD) rating.

1064 nm (Nd:YAG) or 10,600 nm (CO₂) lasers require specialized filters that block infrared wavelengths.

3. How to Choose the Right Laser Safety Glasses

When choosing safety glasses, please check the following key parameters:

①Wavelength Range: Ensure the glasses cover the precise wavelength of the laser you are using (e.g., 532 nm, 808 nm, 1064 nm). If the laser's operating wavelength is 808 nm, you can choose our LP-ATD laser safety glasses from LaserPair; if the laser's wavelength is 1064 nm, you can choose our LP-DTY laser safety glasses from LaserPair.

②Optical Density (OD): Optical density (OD) refers to the laser safety glasses' ability to attenuate laser energy. The higher the OD value, the stronger the ability to attenuate laser energy. Choose an appropriate OD value based on the power of the laser equipment you are using. For power below 800 watts, you can choose OD5 laser safety glasses; for power between 800-1500 watts, you can choose OD7 laser safety glasses.

③Certification: Check for compliance with standards such as EN 207/208, ANSI Z136, or GB 30863.

Even if they look similar, glasses may malfunction if the laser wavelength does not match the protection range of the glasses.

4. Conclusion

Regardless of whether the laser is visible or invisible, we should wear laser safety glasses for any laser above Class 1. Each wavelength carries specific risks, and only wavelength-matched and certified glasses can truly protect our eyes.