I always sit in front of the computer all day. And my eyes always feel tired. My friend said that radiation glasses will protect my eyes from the computer radiation. So will it work well?
"Computer radiation"? What's that? My suspicion is the whole notion is a scam to get people to buy unnecessary stuff. Can you provide any reference to it?
CRTs work by shooting electrons at a phosphor screen. The electrons can be said to be very low energy beta radiation but if you are farther than about 12" from the screen there is no way for any of the electrons to reach you. If you are using a flat screen there is no significant radiation. Your eyes probably feel tired due to eye strain. During work you should focus our eyes on distant objects and stretch at least every 30 miinutes or so and that should solve your problem.
color CRTs require a metal shadow mask and the anode potential will be greater than 10,000 volts. this can produce very low levels of x-rays. like you said though, you must be very close to the screen for long periods of time to get any significant dose. flatscreens are a different technology and emit zero radiation.
They will not protect your eyes from radiation. If you have bad eyes and the glasses help you see better, your eyes will indeed feel less tired.
It's (late) 2013 -- who still has a CRT? Well, anyway, even if you have a color CRT, the eyes aren't going to be more sensitive to ionizing radiation (bones can be more sensitive) and most CRTs have thick glass that blocks much of the X-ray emission. In the US, CRT have safety emission standards because CRTs are treated like closed-circuit television recievers: http://www.fda.gov/Radiation-Emitti...es/HomeBusinessandEntertainment/ucm116389.htm By comparison, background radiation is about (varies widely by location) 0.023 milliroentgens per hour. 1 banana = 0.078 μSv, 1 roentgen = 0.96 rem = 9600 µSv = 123077 bananas. Background radiation: 0.023 milliroentgens per hour = 0.2208 µSv/hour = 2.8 bananas/hour US CRT testing requirement: less than 0.5 milliroentgens per hour = less than 5 µSv/hour = less than 62 bananas/hour at a distance of 5 cm. Your eyes might very well feel tired, because of a need for prescription lens, dry eyes, excessive workplace glare, or other reasons. For further reading: http://en.wikipedia.org/wiki/Banana_equivalent_dose http://en.wikipedia.org/wiki/Roentgen_equivalent_man
yes, the viewable area will probably be 1.5 to 2 inches thick or more. the back however is very thin but is coated to absorb almost all of the x-rays emitted. it should be pointed out that CRTs are very dangerous to be playing around with. they are very fragile and require thousands of volts to operate. i once saw where an imploding CRT put a hole through the wall of a trailer.
The radiation glasses would help but unfortunatly it is impossible to completely shield you from radiation, check out this Wikipedia diagram that depicts gamma rays can even go through lead which is the current material used to block radiation: en.wikipedia.org/wiki/Radiation
CRTs do not emit gamma rays. electron emission is relatively harmless. x-rays are mostly absorbed. the radiation emitted by CRTs, for the most part, is harmless with todays CRTs x-ray radiation is probably non existant or at such a low level as to be irrelevant.
Most monitors USED to operate at a refresh rate at or lower than 60Hz. The human visual system could detect that as a subliminal flicker and that adds to eye strain. Modern monitors have selectable refresh rates up to several hundred Hz. Once you get above about 70 Hz, the strain begins to go away. By about 120Hz it is gone from that factor.
Your eyes are tired because your staring at something that less then 60 cm away! LCD don't give off "radiation" other then light and lower EM waves, maybe a few x-rays from a CRT screen but even that is very weak.
