LCD, DLP, PLASMA

[rvincerob1]

I would like to know if all lcd, dlp, plasma tv's are digital? I have a friend that is telling me that they are all digital, except crt. Regardless of the resoultion that the lcd, dlp, plasma display he says that they are all digital tv's because of the circuitry. True or False. Any information on this subject is greatly appreciated.

[meuge]

LCDs are truly digital. I think that plasmas are digital as well. I am not so sure about DLP. However, something you have to keep in mind is this - while CRTs are analog, they have the best picture quality of any display technologies. Large CRTs are bulky and heavy, and they are limited to the ~40s" diagonal size, but the contrast, color and response rate are second to none.

[WMcD]

I'm quite sure they all have digital circuits, someplace before the display.

This is because the all have a single native resolution mode, say around 720 x 1270 for example. If they are fed with a source having a lower resolution it must be up converted. If a higher resolution it must be down converted. You need digital computers (video processors) inside to do this.

The processors can also do other neat things, like reversing the 3:2 pulldown used to put film movies into video.

BTW, the native mode of the display sets the quality of what you're seeing after conversion. So it is one big indication of what the set can do with a good source.

OTOH: A Cathode Ray Tube is an analog devise because the electron gun at the cathode shoots electrons across the phosphor sceen at the front in successive lines to build up (paint) the image. Of course old TV's using pure analog processing via vacuum tubes used them, even before transistors.

LCDs and DLPs (displays) have a matix of elements which are individually addressed to make them tranparent or alter their reflective properties. This is more like a digital thing even though there is always some scheme to get a gray scale (vary the light throughput).

I'd say, therefore, the main analog part of any of them is the CRT.

Gil