How Did It Happen: The Evolution Of The Television

By Author: Heather Protz
Total Articles: 46
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A little more than half of the Gen X was roused by the mysterious invention of the device that could show the happenings around the world either stationary or moving. On a screen none the less! How is that images and videos including full motion pictures were carried across tubes and wires to your doorstep? Since when did viewing things become electronic? How can the television decode the electric signals and produce pictures? Television was not a common appliance in the households of the pre war era. People, although fascinated, were still wary of buying expensive gizmos during that period of time. Never mind that they didn't know much about its advantages. Well, they wouldn't have known much about electricity either. But, decades later, does the present generation know about how the earliest television worked? How the big, tubes and boxes evolved to what it is now? Yes, it's definitely more than just electricity. But do you know what that 'more' includes? Read on further to find out.
Let's get to the basic principle behind the TV. The theory behind producing images on a screen mainly involves the ability of the brain ...
... to connect dots and form images at a distance. For example, if you dissect an image into tiny squares and blow it up, the image will be unrecognizable to a point that the human eye could perceive only a collection of bloated dots. However, if you move to a certain distance away from the screen, you will be able to make out the image. Any display unit uses an image dissector that breaks these images into electric signals and sends them across to the produce or the TV screen
The T.V., as we know it now, is a flat out all electronic device that can broadcast millions of channels through a cable wire or a satellite. But the first T.V. like device that was invented wasn't entirely electrical. It had important mechanical components that produced the images. The first known mechanical T.V. was the one invented by Nipkow in the early 1820's. He used a perforated rotator disk to scan images and reproduce them. His prototype had selenium as a photo conducting device. This was located behind an image dissecting camera with a light detector. The disk scanned the images and passed it over to the photocell, in tiny little sections. It was then carried over to the TV reproducer (usually a neon tube and not a light detector) by radio waves. It might look easy, but it was a lot of work and the images were produced on a reddish screen about the size of a business card. They had poor brightness and contrast, and as electronic tube TVs were being invented simultaneously, mechanical T.V's were soon forgotten.
Up until recently, electronic televisions (mainly CRT) dominated the TV industry. Karl Braun is responsible for inventing the cathode ray tube (CRT), the major component that replaced all other mechanical components in a Visual Display Unit. The CRT was used as both a receiver and an emitter in the electronic television. The images produced by the earliest CRT camera tubes had extremely low electrical output and hence, poor sensitivity to light. Although, independent researches were going on the usage of different receiver tubes, not many were successful. But later on the problem was solved by the invention of a camera tube that could not only receive but also store the electronic signals through each scanning cycle. This new feature of the camera tube has been retained in many electronic display units till this day.
But in the past three years, CRT TV's are going down. With many big players in the cable industry like ATT Uverse switching to Digital TV broadcasts, consumers opt to buy LCD and LED TV.

Heather is a techno geek, who is interested in keeping herself updated with the technology. As a freelancer she likes to write about programming and recent improvements in the computer field. She enjoys watching TV connected to ATT Uverse