TFT Display: Resolution, Color Intensity, Response Time
Getting hold of a suitable TFT panel presents no difficulties, as we said before: an old 15.1" flatscreen monitor makes the ideal basis for building a powerful projector. Most displays offer a physical resolution of 1024x768 (i.e. 786,432) pixels, for playing back high-quality DVD videos or displaying the Windows screen. Some models even offer resolution of 1280x1024 pixels, making them suitable for 3D games, too.
| Designation | Resolution | Pixels | Suitability |
|---|---|---|---|
| VGA | 640x480 | 307,200 | unsuitable |
| SVGA | 800x600 | 480,000 | partially suitable |
| XGA | 1024x768 | 786,432 | highly suitable |
| SXGA | 1280x1024 | 1,310,720 | highly suitable |
| UXGA | 1600x1200 | 1,920,000 | - |
| WUXGA | 1920x1200 | 2,304,000 | - |
The table above lists the principal resolutions; note that resolutions higher than SXGA are seldom available in 15" format, with the exception of some notebook displays. This means the display no longer fits the overhead projector, as its dimensions exceed the light frame. The panel on our projector was taken from an older flatscreen from Iiyama, the 15.1" BX3814UT .
Aside from display size, simple disassembly was a major criterion in our search for a suitable flatscreen monitor. Several factors must be taken into account to avoid destroying any components.
We don't really need to mention color accuracy, as almost all older displays support 24 bit color depth, and hence 16.7 million colors for perfect DVD screenings. Response time poses no problems, even on relatively small displays up to 15 inches: less than 30 ms average is completely adequate for perfect picture reproduction.
