If the TV is well made, the plasma, LCD or OLED credentials will make very little difference to the quality of the image.
In our latest test, the screens are either LCD or LCD IPS.
LCD: An LCD (liquid-crystal display) screen needs a light source behind it, which will either be CCFL (cold cathode fluorescent lamp) or LED (light-emitting diode) technology.
CCFL technology still exists but it's older and is being replaced by LEDs. These cost more at the outset, but are cheaper to run because the lights have a relatively lower power usage.
LCD IPS: In Plane Switching (IPS) is a technology introduced to help improve the viewing angle of LCD screens.