Thread Subject: Re: Revised 2.1.A
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From: Robert_Nerhood@Dell.com
Date: Fri, Oct 19 2007 6:50 AM
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Contrast ratio in this case is the luminance of the bright state (white
screen) divided by luminance of the dark state (black screen). In
talking with the LCD engineers here, they will take anywhere from 5 to
13 measurements across the display and utilize the averages for each
state to calculate the contrast ratio.
From: = EMAIL ADDRESS REMOVED =
[mailto: = EMAIL ADDRESS REMOVED = ] On Behalf Of Gregg
Vanderheiden
Sent: Friday, October 19, 2007 1:15 AM
To: 'TEITAC desktop/portable (hardware) subcommittee'
Subject: Re: [teitac-hardware] Revised 2.1.A
Robert
I think we need to define 'contrast ratio' here so it doesn't
inherit the definition from software content since this is real
luminance. Do we want to use the same formulae we have been talking
about for labels? (e.g. use "luminance contrast" and use
(L1-L2)/L2 with minimum L1 )
Or do you want to use the contrast ratio (L1 + 0.05) / (L2 +
0.05)
Gregg
-- ------------------------------
Gregg C Vanderheiden Ph.D.
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