It does not require a continuous spectrum of light, however it must
have certain wavelengths. It may require a trip to a textbook to
understand it fully, but I will make an attempt.
In a TV, even if it is an LCD, they are using an additive color
mixture. You basically need certain wavelengths of each primary color.
This differs from subtractive colorimetry which is used for example in
printers. In other words you can't make pure red out of orange and
purple. The problem might be well described as color pollution, not
much unlike impurities in a regular CRT.
Now whether we are talking about a phosphor or a color filter matters
not. The color must be pure otherwise the -Y component will have to be
accentualted for good color reproduction, and you never get it. Even
notice on some CRT sets that some of them are better at reproducing
very deep blue. Those are the RPTV CRT set in which you must defocus
the blue because that phosphor is quite inefficient. With the blue in
prefect focus you will not get the right color temperature without
overdriving the blue no matter how new the set is. Other manufacturers
intentionally pollute the blue to bring color temperature up to the
proper level. They have the advanage of being able to display a
sharp blue only part of a scene, but it simply is not AS blue.
Another example would be the low end NAPs of the past, the reds were
orange and while they looked better under bright flourescent lights,
once you got them home, in time you would fall in hate with them. And
there is no fixing this in the color circuitry.
Now I am fully aware that there have been seven color printers, but
such enhancements are simply not practical for display technology.
That's the rules of the game, I didn't make them. Actually I haven't
seen a seven color printer for quite some time, they may have
abandoned the technique. I suspect it may just be too expensive, and
think of what something like that would do to the cost of a TV set or
However, I suspect there is some actual white enhancement going on in
some LCD units, and as many are aware, the color wheel in a DLP
frequently has more than the three primary colors. I say this because
after observing the display on one of those Zeniths which had a bad
(and removed) blue polarizing filter, it could still reproduce white.
Problem is it could only do it in the OSD. There was absolutely no
modulation of the blue in the active video. So where did the white
come from ?
Red green and blue are defined scientifically as primary colors. I
don't know where those standards came from, nor do I care, but they
are there. There is an inversion in the equation when you go from
supplying the light to using incident light. A printer makes red by
mixing yellow and magenta, but in this, it simply doesn't work. In the
subtractive mode, by the same token, the yellow, magenta and cyan have
to be pretty close to the defined complimentary colors or rendition
However there is still the subjective aspect. Some people would find
more pleasing to watch a DLP, and swear that the picture looks better,
and that could be attributed to it using more than three colors. If so
are they watching a more accurate picture, or is it something they
simply prefer, like speakers with alot of bass or something like