From: Christopher Fry <70353.3056@CompuServe.COM>
Subject: Re: Integrated laser arrays for Eyephones
Date: 01 Nov 91 22:39:52 EST



brucec@phoebus.labs.tek.com (Bruce Cohen) writes:

>> The beauty of the fixed array is no moving parts and the whole thing made 
>>by VLSI technology. How to you make a laser scan with those constraints?

>Same way you scan an LCD array or an electroluminescent panel: you have
>some (well, a lot, in terms of number of transistors) switching
>electronics which controls when current gets sent to each pixel; the
>switching is timed by the synchronization pulses in the video signal.

Good point. I was assuming the reason you wanted to scan was to cut down on 
the number of lasers. When you've got 1 laser per pixel, whether you scan them
or just keep them on at low power doesn't matter too much, except if the 
minimum power to make them lase is too much for continuous operation [which at
present, I guess it is.]

>Some of the new active-matrix displays are as good we need both in speed 
>and resolution, but they're a tad expensive yet.

How small can you make an LCD? Microlasers are down to 1 micron.

I'm also quite concerned with contrast. I've never seen a CRT that had good 
enough contrast. [I've seen B&W 300dpi monitors. The difference between them 
and a laserwriter output is glare and contrast.]

I've never seen an LCD [backlit or not] that had contrast even as good as the 
best contrast CRT.

>When the TV manufacturers or the laptop computer makers see a significant 
>market demand, they'll use the better displays.

Yeah, and when Detroit sees a significant market demand for better cars, they 
lobby in congress to make them illegal.

Were CDs market driven? I don't think so. Yet they are a higher resolution
audio "display" that's now widely accepted.