Laser safety glasses can be used for visible and invisible light.
Visible Light Laser Safety Glasses
If you are trying to protect yourself from visible laser beams or other forms of hazardous visible light, visible light laser safety glasses are what you need.
Laser safety glasses that protect from invisible light are often clear or nearly clear, because they do not block wavelengths in the visible spectrum (roughly between 400 and 700nm wavelengths of light). Visible light laser safety glasses, on the other hand, provide protection from lasers that operate in the visible spectrum. Because of this, they cannot be completely clear and still be protective.
Okay, so maybe it’s obvious to you that laser glasses that block visible wavelengths of light can’t possibly be clear. But if you’re wondering what the correlation is between visible light laser safety glasses and the beams they protect from, here’s some helpful information:
- Visible light laser safety glasses protect from laser beams within the visible spectrum, which is roughly between 400nm and 700nm wavelengths of light.
- Visible light laser safety glasses are never clear, because if they were they wouldn’t be protecting from any visible beams!
- Laser safety glasses for visible light are basically the opposite color of the beam they are protecting against. This is directly from the principles of what a “color” really is: if it reflects or transmits a certain color, it will appear to be that color. If it absorbs a color, that color will NOT appear through or reflected from the material.
- Laser safety glasses that protect from blue light are generally red.
- Laser safety glasses that protect from red light will generally be blue or green.
- Laser safety glasses that protect from colors in the middle of the visible spectrum, such as yellow beams, will generally be dark purple or brown.
- Visible light transmission (VLT) is correlated roughly with how much protection you have in the visible spectrum. The more wavelengths you’re protecting from, and the higher the optical density (OD), the darker the lenses.
Visible light laser safety glasses are usually the ones people associate with cool colors, lower VLT, and more “space-age” looks when they’re worn by technicians.
The fact of the matter is that, no matter how much intelligence a person has in relation to science and lasers, there will always be people looking for laser safety glasses with clear lenses and really high VLT that protect against visible light. Conversely, there will also be people who are wondering why there are no laser safety glasses that protect from everything between 400-700nm. Neither of these is possible; you can’t protect from visible light without blocking some visible light, and you can’t use a pair of glasses that blocks 400-700nm, because they’d be opaque!
If you have any questions about laser safety glasses or goggles, or visible light laser safety glasses, please leave us a comment below. We’d love to help you out.
Thanks for reading, and stay safe!