Search Menu
Photonics Media Photonics Buyers' Guide Photonics EDU Photonics Spectra BioPhotonics EuroPhotonics Industrial Photonics Photonics Showcase Photonics ProdSpec Photonics Handbook
More News
Email Facebook Twitter Google+ LinkedIn Comments

Telecommunication Systems Minimize Laser Risks

Photonics Spectra
Feb 1999
Bryan A. Tozer, Lasermet Ltd.

The rapid development and implementation of optical telecommunication technology have significantly aided the growth of Information Technology in the 1990s. Ready access to the Internet and the decreasing cost of telephone calls, both nationally and internationally are both the result of the low capital cost and high capacity of optical fiber telecommunication links.
Light-emitting diode and laser optical links that operate in "free space" are increasingly used for short-range data transmission between computers within the same office and between offices where a direct visual contact is available. Free-space ground-to-air and ground-to-satellite communication can also benefit from the use of lasers.
Whenever lasers are mentioned, questions of safety are never far away. The International Electrotechnical Commission is responsible for the most widely accepted laser safety standard, IEC 60825-1, which provides advice on maximum permissible exposures to laser light and classifies laser systems based on a hazard assessment. ("Hazard" is the potential to cause harm. It must be distinguished from "risk" which is the probability that harm will actually be caused.) Except for wavelengths longer than 1400 nm, the possibility of injury from exposure to the radiation arises because the intense laser radiation can be focused to a very small point on the retina, causing local heating and damaging the photosensitive receptors. In most cases where excessive exposure occurs, the damage is permanent and, if the radiation is focused on the macula, there will be serious loss of central vision.
At 1550 nm the anterior portions of the eye absorb the radiation, causing excessive heating and hence corneal burning or cataract. Because the radiation is not focused in this case, the threshold for biological damage is greater than at the shorter wavelengths.

CommunicationsFeature ArticlesFeatureslasers

Terms & Conditions Privacy Policy About Us Contact Us
back to top
Facebook Twitter Instagram LinkedIn YouTube RSS
©2018 Photonics Media, 100 West St., Pittsfield, MA, 01201 USA,

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.