Tech Corner
Plasma vs.
LCD
When
choosing between Plasma and LCD, you are actually selecting between two competing
technologies, both of which achieve similar features. To complicate the decision-making
process further, price and size are two previous considerations that are rapidly
becoming non-issues as LCD TV's are now being made in larger sizes and almost
at competing prices as Plasma.
Despite their similarities, the two technologies are very different in the
way they deliver the image to the viewer.
Plasma's technology consists of hundreds of thousands of individual pixel
cells, which allow electric pulses (stemming from electrodes) to excite rare
natural gases-usually xenon and neon-causing them to glow and produce light.
This light illuminates the proper balance of red, green, or blue phosphors
contained in each cell to display the proper color sequence from the light.
Each pixel cell is essentially and individual microscopic fluorescent light
bulb, receiving instruction from software contained in the rear electrostatic
silicon board.
Whether spread across a flat-panel screen or place in the heart of a projector,
all LCD displays come from the same technological background. A matrix of
thin-film transistors (TFTs) supplies voltage to liquid-crystal-filled cells
sandwiched between two sheets of glass. When hit with an electrical charge,
the crystals untwist to an exact degree to filter white light generated by
a lamp behind the screen (for flat-panel TV's). LCD TVs reproduce colors through
a process of subtraction: They block out particular color wavelengths from
the spectrum of white light until they're left with just the right color.
And, it's the intensity of light permitted to pass through this liquid-crystal
matrix that enables LCD televisions to display images chock-full of colors-or
gradations of them.