How Television Works Essay, Research Paper
How Television Works.
There have been countless inventions that have forever changed the world just by their existence. Many of these have been related to communications, such as a radio, phone, and more specifically the television. Soon after it’s release, millions of families across the nation had their own television set, adding something new and exciting to the list of American pastimes. But what is inside a television, and how do they work? Who invented them and how?
Television receives pictures and sounds from electro magnetic waves sent out from broadcasts. That is a simple and broad explanation. But many years were spent perfecting the television, and learning more about it. The first TV sets were big and bulky, and some were mechanical rather then electronic.
Inside a television set, there are many different parts, which serve different tasks. First the waves are received by an antenna, then they are shot from the electron gun, which is a device the aims and sends the signal. Those beams go through a funnel, which starts to project the image. The projection isn’t one piece as it appears though. It’s actually thousands of little dots lined in place to create a picture. But the fun doesn’t stop here!
One of the biggest parts of a working TV is the picture tube, which has four basic parts. The glass face panel is the screen that pictures appear on. It’s coated in phosphor, which is any material that when expose to radiation, emits visible light. Suspended directly behind the face is a steel shadow mask, with thousands of square holes. This panel is fused to a glass funnel, and the rear of this funnel converges into a neck, which holds the electron guns.
This is where color TV comes in. It’s more complicated then black and white TV, but holds the same principals. Rather then one electron gun there are three for the different colors red, blue, and green. With the three color beams traveling side by side, the holes in the mask ensure that each beam will only hit a certain phosphor stripe- the red, green, or blue. The three phosphors, lighted in different combinations can create any visible color when seen from a slight distance.
The three beams of electrons are directed across the screen by a series of electromagnets which draw the beams across the screen one at a time. The beam draws around 500 lines across the screen, depending on the size of it. Since the pictures have to appear to move, images on the screen must be rewritten 30 times a second!
There are many more steps to transmitting TV signals, broadcasting channels and tuning into channels. There are also many different types of television sets that were experimental before the electronic TV was invented. This is just an overview of how your basic television works.