[PdaOd]

Vision uses tristimulous color perception. This means color is perceived as relative intensities of red, green and blue. These color ranges are broad and have slopes that overlap at the boundaries. This is how we can have a RGB display system for additive color (or CYM for subtractive) and see a range of colors. For example the wavelength of light we perceive as yellow falls on the overlap of red and green perception and registers as equal intensities of red and green. We can perceive that same color by using a display that is emitting red and green light with equal intensity. It's not really making the single wavelength yellow light but rather fooling our perception into thinking that it is. This also shows the limitations of color perception in that we can't tell if the yellow is a pure wavelength of light or a mixture of wavelengths.

The spectral width of the red, green and blue light from the display will determine how deep the colors can be. If the red has energy in the green and blue spectum, then the saturation of the red is reduced. The quality of the color filters in a LCD display determine whether the display looks dull or vibrant.

Another element of visual perception is that it is logarithmic to intensity, which is also true of aural perception. This means that vision is more sensitive in darker areas and less in brighter areas. LCDs have a more or less linear change of intensity in relation to the signal that is fed to it. When the amount of bits are reduced we start to see the quantized steps as banding in the darker areas.

The iphone displays are IMO superior to the ones HTC uses. Video and pictures looks good. Unfortunately for the iphone all that glitters is not gold.