Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Easing Eye Strain with the Right Lenses (2012)

nytimes.com

Post reply on HN
Print view View original

31–40 of 97 posts

Re: Easing Eye Strain with the Right Lenses (2012)

#31

Post by mikeash »

jdavis703 wrote: post #3

I have tried programming with contacts in (usually when my glasses were damaged beyond repair or lost). I can barely work for 6 hours before the contacts dry out, even when using contact lens drops. Does anyone know of tips for finding contacts that are good for computer use?

Have you tried different brands? I started out with Bosch and Lomb contacts, which I thought were excellent. Then one year my doctor suggested that I try Biofinity Toric instead, and it was a revelation. Most of the time I can't feel that they're even there. If I forget whether I have them in, I literally have to see if my distance vision is clear to check.

That is not to say that Biofinity is the better choice, but it's worth trying out some different kinds to see if there's one that works better for you.

Re: Easing Eye Strain with the Right Lenses (2012)

#32

Post by walterbell »

ScottBurson wrote: post #19

There's a more subtle issue with high-index plastic lenses and the new RGB LED monitors: the high dispersion of the plastic interacts badly with the red and green wavelengths of the RGB LED backlight, to produce a much more severe color separation effect when you're looking through a part of the lens not near the optical center. I wrote a blog post about this [0]. For the last couple of years I have been using lenses…

Freeform single vision lenses are marketed as having a larger optical center and less distortion for strong prescriptions, but they are expensive, https://www.2020mag.com/article/premium-free-form-single-vis...

Are the CR-39 lenses noticeably thicker?

Edit: first I’ve heard of wide gamut RGB LED monitors, https://pcmonitors.info/articles/the-evolution-of-led-backli...

Re: Easing Eye Strain with the Right Lenses (2012)

#33

Post by BlackjackCF »

mikeash wrote: post #31
jdavis703 wrote: post #3

I have tried programming with contacts in (usually when my glasses were damaged beyond repair or lost). I can barely work for 6 hours before the contacts dry out, even when using contact lens drops. Does anyone know of tips for finding contacts that are good for computer use?

Have you tried different brands? I started out with Bosch and Lomb contacts, which I thought were excellent. Then one year my doctor suggested that I try Biofinity Toric instead, and it was a revelation. Most of the time I can't feel that they're even there. If I forget whether I have them in, I literally have to see if my distance vision is clear to check. That is not to say that Biofinity is the better choice, but…

Same here! I swapped optometrists and my new optometrist recommended me this brand that had EXTREMELY thin lenses. She said that even though they were more fragile, they were better for people who looked at computer screens all day, since we're much less likely to blink, which causes them to dry out. Thinner lenses require much less moisture from your eye to feel comfortable.

Re: Easing Eye Strain with the Right Lenses (2012)

#34

Post by lobster_johnson »

csomar wrote: post #25
lobster_johnson wrote: post #21

Earlier quoted context omitted.

This is overly sensationalistic and seems to be based on a single bad personal experience. Most people can wear contacts just fine with zero side effects. I've been wearing contacts for more than 20 years. I started with yearly lenses, then monthlies, then dailies, then multi-focal dailies. They've all been superb, and I've never had any issues with dryness. I use contacts from morning to night, only switching to gla…

> overly sensationalistic Maybe, but you can check the Internet about eye dryness. I think there is a lack of stats in this area. The problem is that people react differently. And for some people the damage from dryness is quasi-permanent. So unless there are very established measures/stats, I'd not take risks.

Don't go to the Internet for medical advice. Your opthamologist will determine, based on your experiences, whether contacts are right for you.

The opthamologist will also fit you with the contacts that are right for you. There are tons of different brands and contact lens products. For example, I use Alcon Focus Dailies, and Alcon also launched Focus Dailies Total 1, a more expensive "water gradient" lens that increases breathability and lubrication [1], and for some people who have dryness issues they are much more comfortable. For me, there was zero difference, so I went back to the cheaper kind.

Your comment is a bit like saying that no one should ride bicycles because people with Ménière's fall of their bikes. It's not a proportional response. Plus, you can get training wheels.

[1] https://www.medgadget.com/2014/09/alcons-dt1-water-gradient-...

Re: Easing Eye Strain with the Right Lenses (2012)

#36

Post by corey_moncure »

walterbell wrote: post #32
ScottBurson wrote: post #19

There's a more subtle issue with high-index plastic lenses and the new RGB LED monitors: the high dispersion of the plastic interacts badly with the red and green wavelengths of the RGB LED backlight, to produce a much more severe color separation effect when you're looking through a part of the lens not near the optical center. I wrote a blog post about this [0]. For the last couple of years I have been using lenses…

Freeform single vision lenses are marketed as having a larger optical center and less distortion for strong prescriptions, but they are expensive, https://www.2020mag.com/article/premium-free-form-single-vis... Are the CR-39 lenses noticeably thicker? Edit: first I’ve heard of wide gamut RGB LED monitors, https://pcmonitors.info/articles/the-evolution-of-led-backli...

CR-39 is great. They're scratch resistant, light, have high Abbe number (basically a measurement of the rainbow effect; higher is better), and UV opaque. I've had a pair of CR-39s in a lightweight titanium frame for over 15 years and still going strong.

Re: Easing Eye Strain with the Right Lenses (2012)

#37

Post by ScottBurson »

walterbell wrote: post #32
ScottBurson wrote: post #19

There's a more subtle issue with high-index plastic lenses and the new RGB LED monitors: the high dispersion of the plastic interacts badly with the red and green wavelengths of the RGB LED backlight, to produce a much more severe color separation effect when you're looking through a part of the lens not near the optical center. I wrote a blog post about this [0]. For the last couple of years I have been using lenses…

Freeform single vision lenses are marketed as having a larger optical center and less distortion for strong prescriptions, but they are expensive, https://www.2020mag.com/article/premium-free-form-single-vis... Are the CR-39 lenses noticeably thicker? Edit: first I’ve heard of wide gamut RGB LED monitors, https://pcmonitors.info/articles/the-evolution-of-led-backli...

The maximum thickness is about 4mm -- very reasonable, given the strength of the correction. This is with a fairly small round frame (lens width 41mm).

The first RGB LED monitor I ran into was an Apple Cinema Display, several years ago. I initially didn't understand why I found it so uncomfortable to use. I think all the iMacs built in the last 7 years or so are RGB, as are all the Retina MacBook Pros. -- Well, as the article you linked to explains, they might be GB-r instead (green and blue LEDs with a red phosphor). From a dispersion perspective, GB-r is just as bad as RGB; so are quantum dots and the now-obsolete wide-gamut CCFL. All of these wide-gamut technologies will have much more red-green dispersion than either the old standard CCFLs or WLED.

I wasn't aware of Freeform; I guess that's because I don't use progressives -- I just switch glasses, or slide them down my nose to adjust focus. But it seems to be a lens shaping technology, not a lens material.

Re: Easing Eye Strain with the Right Lenses (2012)

#38

Post by walterbell »

ScottBurson wrote: post #37
walterbell wrote: post #32

Earlier quoted context omitted.

Freeform single vision lenses are marketed as having a larger optical center and less distortion for strong prescriptions, but they are expensive, https://www.2020mag.com/article/premium-free-form-single-vis... Are the CR-39 lenses noticeably thicker? Edit: first I’ve heard of wide gamut RGB LED monitors, https://pcmonitors.info/articles/the-evolution-of-led-backli...

The maximum thickness is about 4mm -- very reasonable, given the strength of the correction. This is with a fairly small round frame (lens width 41mm). The first RGB LED monitor I ran into was an Apple Cinema Display, several years ago. I initially didn't understand why I found it so uncomfortable to use. I think all the iMacs built in the last 7 years or so are RGB, as are all the Retina MacBook Pros. -- Well, as th…

Hmm, does it apply to iPhone and iPad screens, especially with Apple’s “True Tone” display? Given the size of the iPhone user base, your blog post should be better known.

edit: web search did not locate definitive statements about RGB LED in either iPhone or Macbook retina screens.

Re: Easing Eye Strain with the Right Lenses (2012)

#39

Post by superkuh »

At my -10 diopter in both eyes there's no winning with multi-monitor setups. It's a trade-off between chromatic abberation, internal reflection, and edge distortion.

All the high refractive index lens materials I have tried have terrible abbe number and so their chromatic abberation is so bad I can't even LCD text out of the corner of my eye; or read a license plate on a car to the front left of me. I don't even bother with high index anymore.

But moderate refractive index (and decent abbe number) means my lenses are more than a centimeter thick at the edges. In addition to being heavy they are so thick that the nose pad arms don't fit. So the edges of the lenses have to be carved off. This leads to very bad internal reflections.

I've tried exaggerated spherical curvature in order to minimize thickness while keeping a good lens material (high abbe) but that tends to distort (compressing) the image out of the sides the lenses and that leads to nausea.

I wish there were companies out there that would make custom achromatic lens for eye glasses. Their internal reflections can't be worse than what I have now.

Post reply on HN