## Dense LCDs?

Message boards : Science (non-SETI) : Dense LCDs?
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HTH
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Message 747154 - Posted: 2 May 2008, 21:14:30 UTC

According to http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19880008883_1988008883.pdf:
"The density attained in liquid crystal display (LCD) technology has increased by a factor of 100 every 7 years. For an 8" by 11" color display with laser printer resolution we need less than 3x10^7 pixels, which by extrapolation will be available by 1991 and cheap by 2000."

Hmm. Let's do some calculations:
8*rho*11*rho = 30 000 000
88*rho^2 = 30 000 000
rho^2 = 30 000 000 / 88 = 340 909
rho = 583,87 (ppi)

So, they LCD should have about 580 pixels per inch! Wow! Even 200 ppi LCDs are very expensive (thousands of dollars). Most of the LCDs are 100 ppi displays, I think.

So, what happened to LCD density development?

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ID: 747154 ·
Clyde C. Phillips, III

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Message 749529 - Posted: 7 May 2008, 18:14:59 UTC

My LCD is a 19", 1440 x 900 pixel, and measures just over 16" wide by 10" high. That means just under 90 x 90 pixels to the inch. Each pixel consists of three vertical colorbars 1/90 x 1/270 inch wide, if Viewsonic defines a pixel that way. My setup does not allow digital operation so I have to use analog. I don't know if digital would be much better or not. If native resolution is not used that degrades the view by smearing a pixel over two pixels in many places. I can definitely see room for improvement with 90 pixels to the inch at native but analog. What would be necessary is to make monitors, etc at higher pixels-per-inch and look at them until no improvement is seen. Whatever that value was would be the upper practical limit of pixels per inch. I understand that somebody can usually focus his/her eyes on something about 25 cm away, which is called "one power" in microscopy. At that distance one can see something about 0.1 millimeter in size. So a pixel per 0.1 millimeter (254/inch) would probably still be below the optimal fineness.
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HTH
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Message 750559 - Posted: 9 May 2008, 19:28:02 UTC - in response to Message 749529.

Whatever that value was would be the upper practical limit of pixels per inch. I understand that somebody can usually focus his/her eyes on something about 25 cm away, which is called "one power" in microscopy. At that distance one can see something about 0.1 millimeter in size. So a pixel per 0.1 millimeter (254/inch) would probably still be below the optimal fineness.

There were 204 ppi monitors about 7 years ago, but the price tag was something like \$4000 per monitor, huh. Now they are bringing 204 ppi monitors back to the market but the price tag is still something like \$4000! :(

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Message boards : Science (non-SETI) : Dense LCDs?