computer filters

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hi i was wondering if anyone knew what the best type of computer filter screen was to get for an epileptic to stop the comp affecting me so much??? emily :o) x x x

Comments

more computer info

Submitted by Trish on Sun, 2007-12-09 - 17:12

A pair of poloroid glasses would be more useful than a screen filter. The glasses not only cuts the glare, but you can carry them around and not rely on others to have the filters. The glasses a are also great for tv and night driving(esp in the rain). Now they make clear lenses that change with the light. I have a pair of light blue tinted poloroid glasses that I use for computer and tv and will be getting the clear glasses soon. Get an LCD moniter because the screen isn't made of glass and that alone cuts the glare factor down. Lower the contrast and brightness levels....lowering the levels will probably give you a couple of more hours of computer time :) It did for me! Make sure the room is well lit and take breaks. If the refresh rate is your problem I would go digital!!! Analog LCD monitors have refresh rates. The digital LCD monitors don't have a refresh rate, but you need a graphics card that supports digital through DIV or hdmi. If the flicker rate bothers you, the digital moniter is the way to go. They cost a bit more money than analog LCD but the picture is much nicer than analog. Patti

and more computer info

Submitted by Trish on Sun, 2007-12-09 - 18:58

The refresh rates of the VGA(analog) LCD monitors are different than the CRT monitors. There isn't a FLICKER refresh because the backlight is constantly on. The digital(DVI) LCD monitor has a much better response time so there is less strain on the eyes. AS long as you do digital to digital and don't buy a converter(VGA to DVI). A warning to anyone shopping for any type of LCD monitor: some of the backlights are florescent light. Check the specs of the monitor if you have a problem with florescent light. Patti

Re: and more computer info

Submitted by prezno on Fri, 2008-02-01 - 12:58

Some people recommend LCD monitors for their reduction in the FLICKER. This is WRONG. FLICKER and REFRESH in monitors are two DIFFERENT things which may have ta similra source.

Here is some information if you suffer from headaches or dizziness from monitors, INCLUDING LCD monitors. This may not be 100% accurate, and more research is needed, but this makes sense to me:

(1) CRT monitors provide light from glowing phosphors. To simplify, phosphors glow when a picture signal is sent to them. Therefore, whenever the computer "refreshes" the video signal with a new picture, the phosphor will change state and glow. Thus, the image refresh rate on CRTs directly affects the imaging AND the visible flicker of light on the screen (because the image IS the light source). Different refresh rates may be better/worse for different people. Generally, higher is better in reducing flicker (you should see numbers like 85hz and above).

(2) When a video signal refreshes an LCD, tiny liquid crystal molecules in the flat panel line up to allow varying levels of light to pass through. This NOT a light source. This is a LIGHT FILTER and affects the imaging only, NOT the light source or "flicker". The standard 60hz refresh rate on LCD's has nothing to do with the visible flicker because the crystals hold their state once set. It is the BACKLIGHT, typically fluorescent backlight, which is causing the flicker. *****FLUORESCENT LIGHT IS NOT ALWAYS ON.***** Some fluorescent light can flicker based on some multiple of the frequency of the electric current. Some people are badly affected by such fluorescent light.

(3) DVI does NOT have a better response time than VGA. DVI is restricted to 60hz. VGA signal can go higher. But as I noted above, it is not likely the imaging refresh rate on LCD which causes flicker given the nature of the technology. It is the flicker of the light source. So comparing the response/refresh rate of DVI/VGA is like comparing apples to oranges: CRT REFRESH RATE relates to the imaging and the light source, while LCD REFRESH RATE relates ONLY to the imaging.

This information is from my own research. I may be wrong. Please look into this yourself if you suffer from headaches, dizziness, etc. from LCD monitor use. With more and more cheap LCDs hitting the market daily, this is a subject ripe for research.

See this site on people affected by LCD monitors and flicker:
http://www.freewebs.com/eclectives/monitorpain.htm

Some people recommend LCD monitors for their reduction in the FLICKER. This is WRONG. FLICKER and REFRESH in monitors are two DIFFERENT things which may have ta similra source. Here is some information if you suffer from headaches or dizziness from monitors, INCLUDING LCD monitors. This may not be 100% accurate, and more research is needed, but this makes sense to me: (1) CRT monitors provide light from glowing phosphors. To simplify, phosphors glow when a picture signal is sent to them. Therefore, whenever the computer "refreshes" the video signal with a new picture, the phosphor will change state and glow. Thus, the image refresh rate on CRTs directly affects the imaging AND the visible flicker of light on the screen (because the image IS the light source). Different refresh rates may be better/worse for different people. Generally, higher is better in reducing flicker (you should see numbers like 85hz and above). (2) When a video signal refreshes an LCD, tiny liquid crystal molecules in the flat panel line up to allow varying levels of light to pass through. This NOT a light source. This is a LIGHT FILTER and affects the imaging only, NOT the light source or "flicker". The standard 60hz refresh rate on LCD's has nothing to do with the visible flicker because the crystals hold their state once set.  It is the BACKLIGHT, typically fluorescent backlight, which is causing the flicker. *****FLUORESCENT LIGHT IS NOT ALWAYS ON.***** Some fluorescent light can flicker based on some multiple of the frequency of the electric current.  Some people are badly affected by such fluorescent light. (3) DVI does NOT have a better response time than VGA. DVI is restricted to 60hz. VGA signal can go higher. But as I noted above, it is not likely the imaging refresh rate on LCD which causes flicker given the nature of the technology.  It is the flicker of the light source.  So comparing the response/refresh rate of DVI/VGA is like comparing apples to oranges: CRT REFRESH RATE relates to the imaging and the light source, while LCD REFRESH RATE relates ONLY to the imaging. This information is from my own research. I may be wrong.  Please look into this yourself if you suffer from headaches, dizziness, etc. from LCD monitor use. With more and more cheap LCDs hitting the market daily, this is a subject ripe for research. See this site on people affected by LCD monitors and flicker: <a href="http://www.freewebs.com/eclectives/monitorpain.htm" title="http://www.freewebs.com/eclectives/monitorpain.htm" target="_blank">http://www.freewebs.com/eclectives/monitorpain.htm</a>

Some people recommend LCD monitors for their reduction in the FLICKER. This is WRONG. FLICKER and REFRESH in monitors are two DIFFERENT things which may have ta similra source.

Here is some information if you suffer from headaches or dizziness from monitors, INCLUDING LCD monitors. This may not be 100% accurate, and more research is needed, but this makes sense to me:

(1) CRT monitors provide light from glowing phosphors. To simplify, phosphors glow when a picture signal is sent to them. Therefore, whenever the computer "refreshes" the video signal with a new picture, the phosphor will change state and glow. Thus, the image refresh rate on CRTs directly affects the imaging AND the visible flicker of light on the screen (because the image IS the light source). Different refresh rates may be better/worse for different people. Generally, higher is better in reducing flicker (you should see numbers like 85hz and above).

(2) When a video signal refreshes an LCD, tiny liquid crystal molecules in the flat panel line up to allow varying levels of light to pass through. This NOT a light source. This is a LIGHT FILTER and affects the imaging only, NOT the light source or "flicker". The standard 60hz refresh rate on LCD's has nothing to do with the visible flicker because the crystals hold their state once set. It is the BACKLIGHT, typically fluorescent backlight, which is causing the flicker. *****FLUORESCENT LIGHT IS NOT ALWAYS ON.***** Some fluorescent light can flicker based on some multiple of the frequency of the electric current. Some people are badly affected by such fluorescent light.

(3) DVI does NOT have a better response time than VGA. DVI is restricted to 60hz. VGA signal can go higher. But as I noted above, it is not likely the imaging refresh rate on LCD which causes flicker given the nature of the technology. It is the flicker of the light source. So comparing the response/refresh rate of DVI/VGA is like comparing apples to oranges: CRT REFRESH RATE relates to the imaging and the light source, while LCD REFRESH RATE relates ONLY to the imaging.