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ghosting or artifacts that rivals the quality of CRTs.
Contrast
is defined as the ratio of black to white, more simply put, how black is black
when next to a white or clear pixel. In terms of numbers, passive matrix LCDs are usually
able to produce a contrast ratio of approximately 13 - 20:1; in real terms you get a set of
different grays and blues but no true blacks.
Color filter
works by absorbing specific wavelengths of light and only passing light of a
certain wavelengths (In other words, a red filter will remove all wavelengths of light except
for red -- thus it looks red !). White light is made up of a spectrum of wavelengths, so it
can yield the red, green, and blue for displays. However, when filtering out the unwanted
wavelengths, the overall brightness is reduced.
Pixel
is described as one element on a display screen. For a monochrome screen this is
an adequate description. However a color pixel is actually made up of three subpixels: a
red, green, and blue pixel. This is sometimes called a pixel triad. Therefore care must be
taken in describing pixels. In terms of this document, a pixel is the entire element consisting
of red, green, and blue sub- elements. A subpixel consists of the individual red, green, or
blue elements. Gray scales for LC displays are alway s calculated as a function of
subpixels.
Understanding Digital Color Pixels
4 Bits, 8 Bits, 16 Bits, 24 Bits Just how many
colors can they actually generate? Digital video divides the number of colors or gray
scales into a distinct number of points. Based on these "POINTS" the system can generate
a fixed number of colors or gray scales. Manufacturers tend to play games with numbers,
so sometimes it is very difficult to understand "BIT" color talk. First of all, the bit system is
based on the binary system so: 1 Bit color, which is 2 raised to the first power is 2. In other
words a black & white display where the pixel has a state of being either on or off. This can
currently be extended to 24 bits which (at 2 to the 24 power) yields more than 16 million
gray scales.