Path: utzoo!attcan!uunet!snorkelwacker.mit.edu!bloom-beacon!eru!hagbard!sunic!isgate!krafla!adamd
From: adamd@rhi.hi.is (Adam David)
Newsgroups: sci.electronics
Subject: Re: Liquid Crystal Terminals, TVs and Oscilloscopes
Message-ID: <2780@krafla.rhi.hi.is>
Date: 15 Feb 91 02:01:56 GMT
References: <1991Feb13.181820.25718@ms.uky.edu> <1991Feb13.203003.18739@athena.cs.uga.edu>
Organization: University of Iceland
Lines: 24

In <1991Feb13.203003.18739@athena.cs.uga.edu> mcovingt@athena.cs.uga.edu (Michael A. Covington) writes:

>(2) I'm wary of LCD screens because of the loss of readability.
>I *know* that eyestrain is bad for me. I *don't* know if the oscillating
>magnetic field from a conventional terminal will do me any harm.

You mean that CRT screens are easy to read without eyestrain? Now that is hard
to believe. A non-backlit LCD may lack contrast but at least the surface of
the darkened pixels is sharply defined and relaxing to focus on (partially due
to reduced flicker). All CRT displays that I have seen suffer from four main
problems which make them visually tiring to use:
1) flickering.
2) ion emission.
3) poorly delineated pixel dots (fuzzy edges and depth of surface. It is 
   easier to focus on an opaque surface than on a luminating phosphor).
4) CRT focussing circuitry can at best only approximate a true focus over
   the whole of the screen area.
Some of the new paper-white low-emission hi-rez CRTs that are becoming
available are a minor improvement to frying one's brains on older types,
but active-matrix LCD screens of reasonable size and response time should
be getting cheaper. It won't be so long until people will be saying
"CRT, what's that?"
--
Adam David.  adamd@rhi.hi.is