LED televisions are very popular. Consumers are replacing cathode ray televisions with modern LED TVs in large numbers. Some consumers go to their local electronic super store and buy a model a part time salesperson says is best. The consumer looks briefly at the picture on the LED TV display unit. A sale takes place if the picture looks good and the sound is okay according to the consumer.
Smart consumers take time to learn the technology aspects of an LED TV before making a purchase. The goal of this article is to help consumers understand technology as it applies to choosing LED televisions.
Before LED TV technology, televisions were the cathode ray type. A projected ray of charged particles struck the inside of a large vacuum tube. Luminescence caused the particles to appear on the screen in a quickly repeating series of lines, one line at a time. Because of the fast projection, the picture appeared to occur all at once.
LED television technology is much different. A light shines behind groups of crystal pixels set in a box like grid pattern. Each pixel has three sectors with each one of the three primary colors. The light that shines from behind the grid will shine through to the front of the screen if not controlled in some manner. An electronic gate controls how much light can shine through each of the pixel grid areas. This determines the amount of light and color that is visible on the LED television screen.
Consumers notice and wonder about differences in price and performance of LED televisions. Some LED TVs use less expensive and older technology to backlight the pixel grid. LED TV backlighting produces a light technically similar to fluorescent lighting at home. LED television backlighting has constant intensity once powered. Dim switches at home work on incandescent lights but not on fluorescent lights for the same reason. LED television sets using older backlighting technology never look completely dark when power is on. Some back lighting leaks through to the screen, leaving it a shade of grey. Inability to go black affects contrast.
Some LED TVs use newer technologies allowing variance of light to pass to the front of the screen. The best systems allow sections of the grid to go black so that better contrast is possible. This is why some LED television screens have better image contrast than other sets.
Yet another technology uses no backlighting at all. This technology provides side lighting. Benefits of this technology are the brighter picture that is possible. The downside is a return to limited contrast loss. Without the ability to control or dim the amount of light the problem of contrast is again present. Understanding LED television technology helps consumers decide which picture is more acceptable. As of today, no system provides the perfect combination of brightness and contrast.
In addition to technical aspects affecting picture quality, consumers need to investigate the number and type of connections provided on screens they may buy. There are many analog and digital content players on the market, not all using the same connector systems. These are the technical and practical considerations for buying LED television sets.