This article explains how each TV technology displays an image and the differences between them. You can learn about it in more detail here. Plasma screens contain tiny pockets of gas that get excited when voltage is applied to them, turning them into a state of plasma.
In that state, the voltage then strikes electrons of mercury, turning them into ultraviolet UV light, which isn't visible to the human eye. The UV light then passes through phosphor cells; each pixel contains red, green, and blue phosphor cells. Thanks to these phosphor cells, the TV can turn the UV light into colors that are visible on the light spectrum. Essentially, plasma TVs don't require a light, and each pixel is self-emissive, so how one pixel displays itself is independent of the next pixel.
Since each pixel emits its own light, blacks are really deep. When the television wants to display black, it simply emits no light at all for the selected pixels. However, these aren't perfect blacks because each pixel retains a bit of voltage, leaving a bit of light to pass through.
Each pixel emits light in all directions, creating wide viewing angles , so the image remains accurate when viewing from the side. The pixels aren't excited continuously, but in short pulses, and some plasma TVs can pulse up to times every second.
The naked eye perceives this as flickering, and some people are very sensitive to this. There can also be some advantages to this; since each pixel holds a certain charge, it's ready to turn on and off as needed, resulting in minimal motion blur. This means that fast-moving content, like in sports or video games, appears smooth. One of the downsides of plasmas was how they suffered from occasional image retention if they displayed the same image for a long period.
So if you watched the news for about an hour, with all of its static displays, then switch channels, you'd still see the outline of the static elements. Eventually, they disappeared, but it could have been particularly annoying. Also, after several years in use, plasmas suffered from permanent burn-in. This happened when the phosphor cells simply stayed stuck in one color and couldn't display any colors. Unfortunately, there was no way to avoid eventual burn-in, and almost every plasma TV suffered from it.
OLED TVs have similar characteristics to plasmas with their infinite contrast ratio, wide viewing angles, near-instant response time, and to a lesser extent, the risk of permanent burn-in. An LCD screen is composed of two parts: the actual liquid crystal display and a light source at the back of the screen called backlight.
A light diffuser is placed between the backlight and the LCD screen to make the source of light uniform across the screen. The LCD panel doesn't emit light by itself, and this is why it needs a backlight; it only acts as a filter to block the light on a per-pixel basis.
The backlight is always on, and the pixels in the display rotate to allow light through, creating the colors needed for the image. Computers — History and facts about the invention of the computer. A historical timeline of the first mechanical and electronic computers to modern day computers.
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TV Technology. Cite This! Buying a TV can be frustrating. A baffling array of acronyms, formats and tech jargon. Then you can make your choice and crack on with watching your favourite show or movie! This article was updated in May The image was created by firing electrons through the gun onto a screen, exciting the particles on it. These TV formats have been on the decline since the early s with the introduction of far smaller LCD screens and these days you would be extremely hard pushed to find any retailer selling them.
Go here to shop for televisions at Ebuyer. LCDs are thin displays normally used in laptops, computer monitors and TV screens. A liquid crystal display is a special flat panel which can block light, or allow it to pass. The panel is made up of segments with each block filled with liquid crystals. The colour and transparency of these blocks can be changed by increasing or reducing the electrical current.
LCD crystals do not produce their own light, so an external light source like a flourescent bulb is needed to create an image. Instead they are simply an updated version of the previous LCD generation. These are far more efficient and smaller in size, meaning the TV can be even narrower. This enables focused lighting areas — meaning specific cells of brightness and darkness can be displayed more effectively.
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