Wednesday 29 May 2013

LED Light Can Damage Your Eyes Permanently

A new research has demanded that LED light may cause everlasting damage to your eyes.
A new research has demanded that LED light may cause everlasting damage to your eyes. The research claimed that the exposure of LED light can cause permanent harm to the retina of human eyes.

Once the retina cells are destroy by prolonged and continuous exposure to LED rays, they cannot be replaced and will not re-grow, ThinkSpain.com explained. So, it’s a very worried situation because computer, mobiles and TV screens, and even traffic and street lights, have been gradually replaced with LED.

What is LED?

A light-emitting diode (LED) is a semiconductor light source. LEDs are used as indicator lamps in many devices and are increasingly used for other lighting.

blue LEDs and cool-white LEDs are now capable of exceeding safe limits of the so-called blue-light hazard as defined in eye safety specifications such as ANSI/IESNA RP-27.1–05: Recommended Practice for Photo biological Safety for Lamp and Lamp Systems.

Other disadvantage:-

LEDs are more expensive than any other lighting technologies; in 2010 the cost per thousand lumens (kilolumen) was about $18. The price is expected to reach $2/kilolumen by 2015.

Cool-white LEDs with high color temperature emit proportionally more blue light than conventional outdoor light sources such as high-pressure sodium vapor lamps, the strong wavelength dependence of Rayleigh scattering means that cool-white LEDs can cause more light pollution than other light sources. The International Dark-Sky Association discourages using white light sources with correlated color temperature 2700K-3000K.

Dr. Celia Sanchez Ramos, investigator at Madrid’s Complutense University, told that “retina never regenerates itself once it has become damaged.”


Dr. Ramos said LED lights are made up of rainbow longitude waves, and it is the blue part, which causes the problem.
“LED is fantastic if there is adequate protection,” she claimed.       
 
Blue LED light bulbs are the most utilized color of LEDs, and are used on everything from cell phones to television sets to medical equipment. Theories about harmful effects began with complaints from consumers about the intensity of the light and include such things as eyestrain, headaches, sleep disturbances and cancer.

Researcher said that everyone should use LCD monitor for their computer because everyone works on computer from very near distance.

UV light radiation

from 100 to 280 nm. (The radiations with wavelengths from 10 to 180 nm propagate only in vacuum and thus are of little value for our investigation. (Navy Environmental Health Centre, Ultraviolet Radiation Guide, 1992 'UVRG1992') The radiation is transmitted through air and through quartz but absorbed by ordinary glass. (UVRG1992)

UVB: from 280 to 315 nm; (The radiation is transmitted through air and through quartz but absorbed by ordinary glass.) [UVRG1992]

UVA: from 315 to 400 nm; is easily transmitted through air and glass. (UVRG1992)

UVA2: from 320 to 340 nm. (It is harmful to the skin.)

UVA1: from 340 to 400 nm. (It is protective.) [Source: National Institute of Health]

Visible radiation: from 380 to 800 nm

The absorption of UVB induces direct DNA damage: basis changes, induced covalent (abnormal formation of chemical bonds), strand breaks (DNA strands drift apart). UVA radiation and visible light are not absorbed by DNA but by exogenous or endogenous chromospheres that can, in an excited form, degrade the genome.

Humans have their eyes open for around 6,000 hours a year, and most of this time they are exposed to artificial light — for which reason Dr. Ramos says the best way to prevent damage is to “close your eyes often to soften the impact”.

She also said “using good sunglasses with UV filter rays, and a healthy and varied diet rich in Vitamin A, which comes from spinach and peppers — will protect the eyes”.


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