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The physics of the TV you want to buy.

If you're still reading you're interested in a High-Def(HD) TV, but the options are mind boggling and they all sound the same. I'll try to shed from light on the physics of these types to try show the difference between LED and LCD.

Any TV runs using electricity, so we can be sure they use an electric current to excite small pixels of some type to display a picture. The type of pixel will be discussed later in this blog. For now we shall discuss the pixel resolution. the choices are 1080p,1080i, and 720p. the number stands for the lines of vertical resolution, for simplicity we will say that the more lines of vertical resolution the more precise the picture will be. Imagine you see a sand castle, the finer the grains of sand(the more grains total), the less you will notice that the castle in comprised of many small pieces. same with the pixels. the more there are the smaller they are and the clearer the picture. The p or i refer to the way that each screen changes from one moment to the next. The p is for progressive scan which means that the images that move on the screen will be primary at any point so the moving images stand out more than the stationary ones(this allows allows for less data to be saved for a background of the scene since there is less dynamic picture). The i stands for interlaced, which also means that the pixels refresh at the same time in a line. This gives no depth for moving objects and forces the tv to refresh pixels unnecessarily.

Now we can focus on the difference between LED,LCD and plasma. LED stand for light emitting diode, which is an electrical gate that only allows the flow of a current through a certain direction. depending on the amount of current passed certain LED's will light displaying a color. the efficiency of a light like this is better than 90 percent of the power put in is gotten back as light. to put that into perspective a standard light bulb puts out around 5 percent of the energy used as light. so the LED is a very cheap TV power and the screen looks great from all directions.

LCD stands for a liquid crystal display. this is basically a complicated version of the display on a calculator. The particular crystal used in these TV's has properties that react when a current is passed through. on a calculator the segments turn black when a current is applied to the segment. The TV works the same way but the varied level of current applied to each pixel creates a different color. The reason this happens is that the current polarizes the pixel or segment of crystal which allows only certain wavelengths of light to pass. The downside of this screen is that it is best viewed from the front. a similar occurrence is a sunset with is viewed through our atmosphere which does the same thing that the screen does to the light passed through it where the relative thickness of the screen and atmosphere is slightly thicker than when viewed from the front.

Now that you really don't care about why each TV is better I'll tell you that LED is more energy efficient and can be viewed from any angle with the same lovely picture. so to recap, 1080p LED will be lovely and cheaper over the years.