Search Menu
Photonics Media Photonics Buyers' Guide Photonics Spectra BioPhotonics EuroPhotonics Vision Spectra Photonics Showcase Photonics ProdSpec Photonics Handbook

Reconsidering What 'Visible' Means

Facebook Twitter LinkedIn Email Comments
Laser safety standards have called the spectral band between 400 and 700 nm "visible" for Class 2 lasers since the drafting of the first ANSI Standard in the early 1970s. Although it's technically true that these wavelengths are visible, a wider range can be seen by the human eye. In developing the new ANSI Standard Z36.6 the exact definition of the term "visible" is under debate.

Many standardization efforts define visible light as that which elicits a visual response, and clearly this varies from individual to individual. The International Commission on Illumination defined the visible spectrum as 380 to 790 nm. But even this range is questionable because some human eyes can detect UV wavelengths down to 310 nm. Before the definition of visible is solidified, US Army researchers are awaiting results of studies of aversion response, looking particularly at how pupils close in the 400- to 440- and 650- to 700-nm spectral regions under laser light.

Photonics Spectra
Jan 2003
ANSI Standard Z36.6As We Go To PressBreaking Newslaser safety standardsPresstime Bulletinvisible light as that which elicits a visual responselasers

back to top
Facebook Twitter Instagram LinkedIn YouTube RSS
©2020 Photonics Media, 100 West St., Pittsfield, MA, 01201 USA, [email protected]

Photonics Media, Laurin Publishing
x Subscribe to Photonics Spectra magazine - FREE!
We use cookies to improve user experience and analyze our website traffic as stated in our Privacy Policy. By using this website, you agree to the use of cookies unless you have disabled them.