The Difference Between Plasma, LCD, LED, OLED, And QLED Televisions. There have been many changes in television technology over the years. Technology has had a major impact on the television market in the twenty-first century. While CRT and rear-projection TVs were prominent in the year 2000, plasma, LCD, LED, OLED, and QLED TVs quickly overtook those technologies and are now the most widely used displays on the market. 1. Plasma TV. When an electrical current is supplied, the gas inside each of the three small cells emits either red, green, or blue light. There is a pixel-by-pixel display on the screen that shows the percentage of red, green, or blue in each individual picture element (pixel).It does not emit x-rays, unlike cathode ray tubes, which do. Thinner screens are more common. excellent brightness and contrast. As a result of the screen's high power consumption, it becomes uncomfortable to use. "Burn in" can be caused by bright, static visual eleme...