Are you wondering why your laser safety goggles are so dark? Here is the explanation you’re looking for.
Why Your Laser Safety Glasses Seem So Dark:
Some laser safety goggles may offer coverage over a relatively short band of wavelengths and be very dark, while others offer coverage over far more wavelengths and yet are very clear. This can be confusing when you consider the fact that all of these wavelengths are considered wavelengths of light.
- Laser safety goggles can cover wavelengths of light between 100 and 15,000 nanometers. The visible light spectrum resides (roughly) between 400 and 700 nanometers. This means that coverage outside of the 400-700nm range will not affect your vision because it’s blocking light that you can’t see (such as ultraviolet and infrared).
- Many different lasers operate at different wavelengths, and the operating wavelength doesn’t necessarily correlate with the danger of the laser. If you have a laser capable of harming your eyes which operates at a wavelength in the visible spectrum, you will need to have laser safety glasses that will not be clear (and may be dark) because you need protection in the visible spectrum.
- If you are working with a laser in the visible spectrum and you need high optical density coverage from it, you will need darker lenses than if you needed lower optical density coverage (3 or below), as lower OD’s let more light through the lens.
- If you are ordering a plastic material of laser safety goggles (polycarbonate, acrylic, etc.), your lenses will probably be dark due to the nature of plastic laser lenses.
- If VLT is especially important to your laser operation, it is a good idea to look for glass laser lenses that have the coverage you need. Glass generally has higher VLT than plastic, and is therefore a lighter color.
Some laser types require darker lenses, and there is nothing that can really be done to get around it. Conversely, other laser applications operate well outside of the visible light spectrum, so they are easy to find with higher VLT. Some lasers fall in between these two categories. In that case, you should shop around or call your supplier to see what can be done to get the highest VLT possible for your laser application.
If you have any questions about laser safety goggles, take a look at some of our other posts, and thanks for reading!