Personal computing discussed
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just brew it! wrote:LCDs don't flicker just because you reduce the refresh rate. They just refresh the image less frequently.
I call BS.
morphine wrote:No offense, OP, but almost nothing you said actually makes any sense. CRTs will just make a bad situation worse because then you have to try and focus on blurry pixels and end up tiring your eyes even further.
joselillo_25 wrote:just brew it! wrote:LCDs don't flicker just because you reduce the refresh rate. They just refresh the image less frequently.
I call BS.
You are not right sorry, reducing the brightness and the hz of your lcd could make your monitor flick, not too much like a ctr but a bit to have some good effects in your eyes. This is called Pulse Width Modulation and you can search about it.
joselillo_25 wrote:Is not as good as a crt but could work for some people.
The trick works, just if some of you have the same eye problem a lot of people is having try it for some weeks.
I have visit several doctors and no one have help me on this like return to CRT. And this eyes problem has appear the last decade, prior to this people usually have eye strain or headaches but not this focus problems that have appear just when people started to use lcd and phones.
Obviously if you do not have this problem you are not going to understand anything.
joselillo_25 wrote:The more common problem usually is a lack of focus, a permanent damage in the motor muscles of our eyes that makes focus really slow in real life situations.
just reduce the LCD to 25hz progressive, you will start to see good effects in your eyes from the first day.
just brew it! wrote:I know how PWM works. If turning down the monitor to 25 Hz also slows the PWM down to 25 Hz that is a horrible design which will look terrible. 25 Hz flicker is not something you want!
jensend wrote:Increases in screen related eye strain since the advent of smartphones aren't due to LCDs, which many of us were using rather earlier than that. It's because everyone's staring at their darn phones all the time.
K-L-Waster wrote:OP, I hate to say it, but the reason you're having trouble focusing now more than you did in the 90s is because your eyes are 25+ years older and the lenses are getting stiffer.
K-L-Waster wrote:I do understand. Now that I'm 50 (ouch!) trust me, I understand.
Thing is, I get the exact same thing when I read stuff on paper -- it takes several minutes to be able to focus on distant things after reading a paper document. Pretty sure that has nothing to do with the refresh rate....
joselillo_25 wrote:No no, this is a terrible mistake my friends. People have been using monitors, tvs etc... massively since the 80s, is not true that people use screens more now.
joselillo_25 wrote:sure, that’s why my 20-year-old cousin has the same problem and the eye doctor tell her to make "eye exercises" to recover the focus again. You can go and ask an eye doctor if is true that more and more people are asking them for this specific problem.
just brew it! wrote:joselillo_25 wrote:No no, this is a terrible mistake my friends. People have been using monitors, tvs etc... massively since the 80s, is not true that people use screens more now.
Desktop monitors and TVs of the 80s were typically at arms' length or further away. Now people stare at laptop and smartphone screens, which are typically much closer to their eyes. Makes a big difference.
Also, unless you were a software developer back in the '80s, you did not typically stare at a monitor 40+ hours a week.
The Egg wrote:just brew it! wrote:joselillo_25 wrote:No no, this is a terrible mistake my friends. People have been using monitors, tvs etc... massively since the 80s, is not true that people use screens more now.
Desktop monitors and TVs of the 80s were typically at arms' length or further away. Now people stare at laptop and smartphone screens, which are typically much closer to their eyes. Makes a big difference.
Also, unless you were a software developer back in the '80s, you did not typically stare at a monitor 40+ hours a week.
Yeap. Not sure where the OP is living, but the majority of today's kids (in western countries) all have their own personal phones/tablets, which they're using all day, every day (even during school), and then laying in bed with the screen 6 inches away from their face. This is compared to the 80's and earlier, where you had a 27" or less TV halfway across the room (thus, a substantially smaller fraction of the field of vision being occupied), and your parents yelled at you if you were watching or playing games on it for more than a couple hours at a time.
If it were somehow possible to come up with a useful number based on daily screentime (in seconds) multiplied by % FOV occupied, it would probably be 10x higher in today's kids than in the 80's and prior.
Redocbew wrote:I wonder how many phones are made today that still have an LCD panel instead of AMOLED or some other kind of OLED display. Seems like those are a lot more common now even outside of flagship devices.
Taxythingy wrote:OP: Unless and until you can provide proper citations for what you are describing, I strongly disagree with your conclusions.
I can give three partial explanations which might fit:
1. CRT monitors have (or may have, I forget) a tendency to be brighter than many LCDs, which will generally reduce the eye's pupil size more than an LCD, given similar ambient lighting conditions. That results in a greater depth of field which will mitigate some out-of-focus issue that are present in the eye. It isn't a reason to use CRTs, it means you need more light in the room.
2. The ambient light in the room is now provided by watt-equivalent compact fluorescent bulbs rather than incandescent. These emit on specific wavelengths and are rather peaky, even after going through the phosphors on the bulb. They don't provide the same useful illumination when at an equivalent lumen output, as some wavelengths of light are rather lacking. This might result in the eye's pupil getting larger, and i refer you back to #1 at this point.
3. You have an uncorrected vision difficulty, which is leading to eye strain. Tired muscles don't want to work as well. Go see an optometrist.
What you describe otherwise isn't how the body mechanics work. The eye doesn't use peripheral muscles vs central muscles - it's all one system. A lack of focus is generally either presbyopia, myopia, or astigmatism, which are essentially permanent but correctable changes in the eye shape and/or lens hardening, where the eye muscles can't adapt the lens to the shape needed. Slow focus is primarily driven by tired muscles and by age - see lens hardening above, and indirectly by illumination levels, also as described above.
Generally, I would suggest you increase the brightness in the room, dump any fluorescent bulbs in the room and replace with high-CRI LED bulbs (or incandescents, if that rings your bell), make sure you have a decent monitor to use, get up and move around frequently rather than sitting for long periods of time, and get outside frequently so your eyes get to use that long-distance mode that was bred into them over quite some time. Visit your local qualified optometrist/optician, preferably one who has the skills to refract without relying on the autorefractor. Bonus points if they run their own private practice, and/or have a complimentary degree in optical physics, and/or can't take you for the next 6 weeks because all the professional musicians and sports people are filling up their appointment book.