Date: Wed, 10 Oct 2001 08:59:00 +0800 From: Raymond <[EMAIL PROTECTED]> Subject: Re: [LIBRETTO] Re: Nuts and bolts of impoving LCD brightness
>So you're saying that using a material there that isn't reflective like a mirror, but >spreads/diffuses the reflected light might brighten without creating a second image. Well we used to have one of those panels that you'd put over an OHP and plug into a computer and turn the OHP into a data projector (REALLY old - this thing was black and white and couldn't even do a VGA resolution). I remember one time we were trying to figure out why it wasn't working, obviously we couldn't leave it on the OHP because we'd be blinded. We put it over a mirror surface and the double image was so bad we couldn't see a thing but we put it over a piece of paper (considerably more diffuse) and we were able to see a clear image with only the slightest blurring at the edges caused by the shadow. We only had a single light bulb source at the time, with something like a bright day the extra diffuse light would be even better. >>Of course, Palm-style PDAs get across that problem by having the reflective layer >right up against the LCD itself ... I wonder if thats possible on the Libretto ... > >"right up against the LCD itself" ... Geesh... how much room is there between the >back edge of the LCD and the case? I was of the impression that laptops had the LCD layer in FRONT of the substrate (in front of which comes the front polarizer), similar to your wristwatch. The Palm has the LCD layer on the BACK of the substrate and right up against the reflective layer. This has the dual effect (presumably) of eliminating the double pixel effect and protects the LCD from pressure when you write on the screen (notice you don't get the rainbow effect when pressing on a Palm screen that you do pressing on say a calculator screen). I got this impression because if you have a look at the parallax shift when looking at say a smudge on a Palm screen versus the pixels, its quite large (I then actually took my Palm apart and confirmed this). Doing the same on a laptop screen though results in almost no parallax shift. I'm thinking this is because the substrate is used as part of the backlight diffusion mechanism on a laptop (I don't know how a Palm does it but somehow the backlight in fact diffuses off the LCD layer and not off something behind the LCD). >I wonder how it manages to focus them all onto the flat surface of the screen. Nothing needs to focus, the double image I refer to is the image of the initial pixel plus the image of its shadow (have a close look at your wristwatch from the side). >Also, by adding the reflective material and pumping up light output from the >fluorescent illuminating bulbs, do you then end up running the risk of the image >beginning to 'wash out' How would the image get washed out given that the image is formed by the LCD BLOCKING light? (I'm thinking about how the LCD clocks and displays in your car work - the backlight is always on but during the day you see the reflection off the back layer and the backlight IS washed out, at night you seee the light from the backlight). - Raymond ************************************************************** http://libretto.basiclink.com - Libretto mailing list http://libretto.basiclink.com/archive - Archives http://www.picante.com/~gtaylor/portable/faq.html - FAQ -------TO UNSUBSCRIBE------- Reply to any of the list messages. The reply mail should be addressed to: [EMAIL PROTECTED] - Then replace any text on the message's subject line: cmd:unsubscribe --------TO UNSUBSCRIBE DIGEST------ Do above but with this on subject line: cmd:unsubscribe digest **************************************************************
