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From: laser-lovers@uw-beaver
Newsgroups: fa.laser-lovers
Subject: Re: round vs. square pixels
Message-ID: <1281@uw-beaver>
Date: Wed, 5-Jun-85 13:50:46 EDT
Article-I.D.: uw-beave.1281
Posted: Wed Jun  5 13:50:46 1985
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Organization: U of Washington Computer Science
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From: Nick <NNicoll.ES@Xerox.arpa>

I would like to join and enlarge a discussion of the shape of pixels to
include the size of pixels.

As most of you might know, a scanning laser places an oval shaped pixel
with the height/width ratio dependant on the distance the pixel lies
from the centerline of the paper in the feed direction.  I believe the
ratio varies by ~15 to 20%.  Fonts designed for such printers should
take that variation into account but the ones I've seen don't.  There is
a noticable variation between characters at the edge, and characters in
the middle of a page printed on a scanning laser printer.

This variation also changes the size of the pixel, but not as much as
the different printers of either scanning or cartridge types do.  I
believe the Imagen 10-240 has a significantly smaller pixel size than
the Canon LBP-CX but I have not had a sample of both under my
microscope, I'm just going from eyeball measurements.

If anyone does have the results of actual measurements I'd be glad to
hear from them.

\\ Nick