Presbyopia

I used to do terminal strip projects.. No more. I used to do breadboard prototypes... No more. I used to do throughhole prototypes...No more. Now I just use 1206 caps and resistors for quicker smd prototyping.

D from BC British Columbia Canada.

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I am short-sighted (at least in my right eye), and taking off my glasses lets me work with 0805's and SOT-23's.

A decent binocular microscope takes you quite a bit further.

-- Bill Sloman, Nijmegen

I lost my accommodation two or three years ago, but I'm lucky being shortsighted naturally. 0603s and 0.5mm pitch QFPs are no bother at all. But for someone coming from the normal-to-long end, it must be a bugger.

My brother got me some very useful clip- on short- range work glasses that fit on my normal ones, and I use these a lot for reading- so much better than varifocals, that alwatys seem wrong for everything.

I thought about getting laser eye surgery. But haven't found out yet if it could degrade my near vision. I also take off my glasses for small components.

D from BC British Columbia Canada.

Old age degrades near vision due to stiffening of the lens.

I originally had R-K in the early '90's, then had one lens replaced (cataract) with artificial about 5 years ago. I see pretty good, but I need to go back in now for a focus/astigmatism tweak.

I'm approaching bionic... Titanium hip joint, stent in heart, artificial lens in eye ;-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
         America: Land of the Free, Because of the Brave

Mostly. There was a buzz a few years back about a guy who showed some cases are due to growth in diameter of the crystalline lens.

The control muscle is roughly a torus surrounding the lens, attached to it and pulling on it with "ropes." Imagine a trampoline. Unlike the rest of your body, the lens grows throughout life. When it gets too large across, the "ropes" grow slack & the lens is left in its most relaxed, non-tensioned state, i.e., for farthest focus. Bingo, presbyopia--the loss of the ability to change focus.

Schachar, a surgeon, noticed that contrary to conventional wisdom, lots of the cataracts he was removing were *not* hard, and so went on to his theory. If your lens isn't hardened, he's got a procedure to restore your accommodation (focusing ability) by tightening things up. Looked kinda scary.

DC: If you're presbyopic and get LASIK'd for far vision, you'll not be focused at near. Once you lose the ability to control your eyes' focal length, you're stuck with one fixed, focused distance--choose it as you will--and glasses for the rest.

Cheers, James Arthur

*Nobody* can work with US-8's and leadless chip-scale packages without magnification. Get used to it.

A Mantis is worth it; it will change your life.

I was working with some SOT-23's and 0805 parts the other day and it occurred to me how big and gross they look.

John

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When I get my lenses replaced, I want to be focussed at about 10". I think they can do that.

John

I own a Mantis with 4x and 10x lenses. It's very nice and I can't work without it.

The rework lady at the place I used to work was in her mid 40's. She did

0.5mm stuff all day long and I never saw her use a microscope. Of course, she has to use glasses when driving a car.

In my next life, I plan to be severely near-sighted.

Bob

Good. I love mine.

When I was a teenager, I could focus on the tip of my own nose. And resistors were half an inch long.

John

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, Because of the Brave- Hide quoted text -

Damn Jim, you're falling apart!!

If they start packing you with lots of gauze (as in Egyptian mummys), maybe it's time to call it quits? :)

-mpm

Check out Zenni Optical--www.zennioptical.net. They'll sell you a set of single-focus glasses with the right prescription and interpupillary distance for _eight_bucks_. Add some reasonably nice frames and good coatings, and it gets up to a stratospheric $39.

I bought myself a pair of very mild reading glasses (+0.5 diopter, 71 mm interpupillary distance), and wow, do they make reading more fun. If your eyes are a bit closer together than mine (like 66 mm) you can get semi-decent ones from the drugstore, so it's reasonable to have several different strengths. I've used +2 and +3.5 for fine work, but I like my ancient Zeiss surgical microscope better.

Cheers,

Phil Hobbs

I'm naturally far-sighted and lost the capability to focus a year ago, almost overnight. My focus was fairly quickly frozen at infinity (anything under about 20' is blurry) so can no longer work without glasses but still function otherwise. My optometrist prescribed standard bifocals for computer work, claiming that engineers didn't like the varifocals because the lower portion was too small. I'm not so keen on the "line" either. I keep catching a glint of light reflecting off the line and double vision near it; very annoying.

Next time I go for glasses I'm going to get these made for monitor distance only and a new pair of perhaps varifocals for TV (more distant than these) and reading.

--
Keith