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HP Forum Archive 19

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LCD darkening
Message #1 Posted by Peter Klein on 15 Feb 2009, 3:20 p.m.

In scanning ads for HP calculators, I have noticed a couple of photos that show significant darkening of the pixels. It looks like every pixel and annunciator in the display is half-darkened even when they are not active. I'm wondering if this is real burn-in, or just an artifact of the camera flash going twice through layers of the LCD as it reflects back at some angles.

Here's an example: http://www.auctiva.com/hostedimages/showimage.aspx?gid=103745&image=229927191&images=229927173,229927191,229927213&formats=0,0,0&format=0

Edited: 15 Feb 2009, 3:23 p.m.

      
Re: LCD darkening
Message #2 Posted by Garth Wilson on 15 Feb 2009, 3:24 p.m.,
in response to message #1 by Peter Klein

The camera angle was just not what the LCD's viewing angle was set for. If you adjust one or the other so they match, the "off" pixels will be pretty much invisible.

      
Re: LCD darkening
Message #3 Posted by Juergen Keller on 15 Feb 2009, 3:32 p.m.,
in response to message #1 by Peter Klein

The contrast can be adjusted by pressing and holding the "C" key, then press "+" for darker and "-" for lighter display.
Never heard that LCD displays can burn-in (but unfortunately, they can leak). The effect on the picture you referenced is just a matter of viewing angle (and perhaps a high contrast setting).
Juergen


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