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The plasma screen
television is a relatively new development. It
used to be the case that we didn't have much
choice when it comes to the humble television.
The CRT screen was the only option. This tube
arrangement limited the size and the viewing
angle of the TV.
This all changed in 1964 when the first
prototype of the plasma screen television came
to life, the main reason for the delay being the
lack of readily available digital components.
A plasma display is an emissive flat panel
display where light is created by phosphors
excited by a plasma discharge between two flat
panels of glass.
What does that mean??
A Xenon and Neon gas mixture is contained in a
glass envelope between two sheets of glass, the
gas mixture being the plasma and the envelope
being a pixel. An electrical current is passed
through the plasma, that becomes excited. The
excited ions collide with each other and produce
rays of ultraviolet light. The ultra violet
light reacts with the phosphor that is coating
each pixel, just like in a fluorescent tube
light.
Different colors are produced by varying the
current flowing through each envelope. Each
pixel contains three sub pixels, a red, blue and
a green one. Each sub pixel is controlled
separately, meaning that each one can generate
over ten million colors.
The advantages of the Plasma screen over CRT
screens.
1. A consistently much brighter, sharper and
crisper image.
2. Very thin construction often allows a much
smaller mounting area.
3. Plasma screens have a much wider viewing
angle.
4. Glare is very minimal and even direct
sunlight does not completely wash the picture
away.
5. Almost seventeen million colors can be
displayed.
The CRT screen is far from dead and buried but
one cant help thinking that its days are
numbered. Plasma screen televisions are getting
cheaper by the year and it is easy to see why
they are dominating.
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