1920x1080 is resolution per se, not per inch or any other measurement. A film or other source would be created digitally or transferred to that format to be shown on any size screen with its own native resolution, optimally one with a 1920x1080 pixel count across the entire panel. A display with any other native resolution would have to downconvert the 1920x1080 to its own format. (No 1920x1080 material actually exists yet in the consumer world.) In other words, display size and pixel count are not inherently related. The requisite pixel count is theoretically possible on displays of any size and kind, except that plasma cells are generally too big to achieve it on anything but a monster, and CRTs have a similar problem with real estate to create the neecessary scan lines.

The area in which scale measurements become important is the chip size that holds the pixels that create each screen image. The tiny LCD and LCoS chips can actually hold that many pixels. The DLP chips wobulate a smaller pixel count to reach the full resolution.