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340 points jbornhorst | 2 comments | | HN request time: 0.001s | source

I’m digging into an idea around eyeglasses, screen-time, and vision discomfort. If you wear prescription glasses but still get headaches, eye strain, or blurry vision after long screen days, I’d love to chat briefly (20–30 min).

Pure research, zero selling.

Interested? Drop a comment below or email me directly at jbornhorst [at] gmail.com. I’ll coordinate a convenient time to talk.

1. klaff ◴[] No.43295626[source]
One solution I haven't seen mentioned is trifocals. Progressive lenses used to be sold against bifocals and trifocals by saying "no lines" but there are some advantages to the old school designs. In particular, progressive designs tend to end up with an hourglass-shaped field of view[^1] in which the horizontal field of view at mid-distance can be so narrow you can't see your whole monitor screen without pivoting your head. The mid-view area on trifocals is significantly wider than on progressives and I found it much more useful for medium distance work of computer monitor or car instrument panel. In addition, the area of distance vision is much wider on the traditional trifocal, which means you don't have to move your head as much or not at all to see out car side mirrors.

[1] It's been maybe a decade since I researched this - at the time I concluded that the hourglass FOV shape was a result of progressive lens designers not having enough surfaces to play with and was unavoidable if they wanted decent near and far areas, which tends to work well when your presbyopia isn't too bad yet. Maybe since then someone has introduced a different compromise in that space (maybe narrower close window trading for wider middle distance region?) but I'm not aware of it.

replies(1): >>43295698 #
2. jayknight ◴[] No.43295698[source]
I've recently started wearing progressives, previously I was constantly putting on and taking off reading glasses (I'm far sighted). My usable field of view is more funnel shaped than hourglass shaped. At the bottom I can barely get both eyes to focus on something up close at the same time, it's only really wide at the top (wear I don't need much correction, just for slight astigmatism). It's better all around than no glasses or keeping my readers on all the time, but it's not as nice as I had hoped.