The characteristics are that a solid white screen will tend to be blue tinted
on one side and red tinted on the other. This is usually a subtle effect and
may be unavoidable with some designs.
|NotTaR of Television Sets : Color balance changes across screen from..
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<< Left portion of screen is.. |
| Bleeding highlights >>
There are several possibilities:
- Purity - this means the beams are landing on the wrong phosphor dots.
This is what would be affected by moving from one location to another
or even rotating the TV on its base without degaussing. If the problem
just appeared, degaussing may be needed.
What do you have near the TV or monitor? Loudspeakers or other devices
which generate magnetic fields can easily cause all sorts of color purity
problems. Relocate the offending device(s) or the TV or monitor and then
See the section: Degaussing (demagnetizing) a CRT.
If the problem still persists, purity adjustment may be needed. However,
this isn't likely to have changed so look for other causes before tackling
- Unequal electron gun to shadowmask/screen distance - the electron beams for
the red and blue video travel slightly different distances on the left and
right sides of the screen so their intensity (due to focus not being optimal
and other factors) in each case may differ slightly affecting color balance.
- Doming - This would only happen in very bright areas and causes the
shadow mask to expand and distort. (Doming should not be a problem with
Trinitron CRTs which use tensioned wires in their aperture grill.) This
would also not really affect left-right color balance in particular.
I don't really know how much of a problem (2) is in practice or whether some
manufacturers compensate for it.
<<Left portion of screen is.. |
| Bleeding highlights>>