10 May
2001
10 May
'01
4:29 a.m.
At 09:10 AM 5/10/01 -0600, Dick wrote:
Evidence of what? The shadow mask or the interference patterns created by
displaying at something close to the dot pitch? Take a 17" monitor (13.5"
across) with a .28 dot pitch. That's about 91 dots per inch (25.4mm/inch /
0.28mm/dot) which gives a top resolution of 1228.5 dots. Now run it at 1280
x 1024, see the "moire" pattern. ? Now try it at 1600 x 1200, its even
weirder.
Your correct of course, with 10 year old technology it is somewhat
difficult. With a modern video card for the PC its trivial.
--Chuck
Color monitors have a color mask, and that color mask has a 'dot pitch'
which defines where you can display pixels. If you attempt to display more
pixels on a line than there are holes in the mask, then you will get
banding artifacts.
I've seen no evidence of this. If this were the case, then the fact that many
display systems use inexpensive 1000 ppm oscillators would cause enough
variation that it would be obvious on those monitors having this feature.
Moreover, horizontal phase adjustment and vertical height/horizontal width
adjustment would be impractical. Amplifier bandwidth issues are a factor in the
practical use range of a given
monitor. However, that has nothing to do with whether a monitor is analog or
digital in nature.
All monitors are analog, they all have amplifiers to convert from the
user's video input into a voltage that can affect the brightness of the
electron beam. Now in "TTL" or "Digital" monitors there amplifiers
respond
in a very non-linear way to the input. Thats the difference. Once it gets
to the actual video electronics they are darn near all the same.
Amplifier bandwidth will determine how "cleanly" the colors shift from one
to the next, colors are produced by a set of three intensities that in turn
become beam intensities, which in turn excite three phosphors to become
light intensity. There is also a frequency response component in the phosphor.
You "can" drive monitors all over the map, eventually you will destroy them
if you allow the horizontal output driver to over heat. However, getting an
acceptable signal out of one is more constrained.
While that's true, it's hard to do.