Evaluation Of Television Technology

Amongst many technologies, Television is also the one that has evolved rapidly in 20^th century as a result of market competition. This evolution has come a way long from huge boxes to flat screens with high definition display, which give more colourful experience than reality itself.

In early 1940s, people enjoyed Black and White Television which worked merely on the basis of white phosphor coated screen which represented an image, when an electron beam painted that image on it resulting into a black and white image. Later on, CRT (Cathode Ray Tube) Technology for generation of coloured images in television came up with three electron beams one for each additive primary colour (red, green, and blue).

Switching to Color

Televisions were black and white by design in the early days, with the first color televisions available by 1940. This early type of color television employed a rotating color disc as a stopgap solution to showing programming in its natural color. The designer of this innovation, John Logie Baird, was dissatisfied with the technology.

LCD or Plasma

Flat screen sets started to appear in the late 1990s. Their immediate advantage over CRT was space. They were also lighter, so could be mounted on a wall and came in bigger screen sizes.

But the choice between CRT and flat screen wasn’t straightforward - in the early 2000s you had the choice of two flat-panel technologies: LCD or Plasma.

LCD panels have a backlight made from CCFL lamps, which shine through a polarising filter and a matrix of colour liquid coloured crystal cells. Each cell lets in a different amount of colour creating a picture.

Digital Broadcasting

The most sweeping change since color television involved digital broadcasts. Rather than employing analog waveforms with distinct signals, digital employs multiplex signal to deliver more information in the same data stream.

From a technical standpoint, the analog signal relays images at 640 x 480, 480i, with a 4:3 ratio. The digital HD form includes enhanced 16:9 ratio options such as 1280 x 720, 720p, and 1920 x 1080, 1080i. Interlaced signals require half the bandwidth of progressive signals, because they do not separate images. Even the smallest digital signal cannot broadcast over an analog channel due to the heightened bandwidth demands.

3D

In the early 2010s 3D television was being pushed as the next big viewing trend, and not for the first time - over the last century there have been numerous experiments with 3D in cinema, such as House of Wax (1953) and Dial M for Murder (1954).

3D even made a comeback back on the huge success of 3D films like Avatar (2009), and that popularity was expected to translate into sales of 3D TVs.

But despite the efforts of manufacturers, 3D TV failed to capture the public’s imagination.

It wasn’t particularly comfortable to watch, you had to wear glasses and you needed to sit directly in front of the set to get the full benefits of the technology.

Happy Learning!

Anamika Gupta

IAAN