TV's have risen in popularity tremendously since their invention, and despite continuing advancements in communication they continue to be a major project across the world. This relevance is in a large part due to the innovation which has kept them higher quality, easier to operate, and/or more useful than ever.
TV's started out using cathode ray tube technology to display a picture. In this setup, a vacuum tube rockets electrons towards a phosphorescent screen. Anodes accelerate the electrons before they are deflected by two coils of electrically charged wire, creating an electric field. These deflected electrons strike the screen and glow in different colors due to the intensity with which the tube shoots them out. It scans left to right, top to bottom, until it finally reaches the bottom, and repeats.
Nowadays, however, TV's work very differently. One style is the liquid crystal display. Lights on the bottom of the TV shine upwards, illuminating the inside of the TV. Two polarizing planes at 90 degree angles to each other block all regular light from reaching the screen. However, between the planes is a section of nematic liquid crystals which are twisted. On each end are glass planes coated with electrons to adjust intensity. As different voltages are applied to these glass panels, they twist and untwist the crystals in order to selectively block light from passing through the polarized plane to the screen. After the polarizing plane are one of three colorizing planes: red, green, or blue. By placing three of these arrangements next to one another, a pixel is created.
Another style is the plasma display. In plasma displays, there are cells of ions and electrons free flowing, which are each pixels. Each pixel has a different color lens to transform visible light into one of the average three RBG. When an electric charge is sent to the cell, the positive ions and negative electrons both move around and combine with their opposites, creating light which passes through the colored panel and hits the screen.
Whew! We need to stop making TV's and get back to books! Seriously, when's the last time someone reinvented the book? I want a plasma book.