What is LED TV ? ( Light Emitting Diode)

LED TV is a kind of LCD television that uses light-emitting diodes (LEDs) to backlight the display rather then cold cathode fluorescent lights (CCFLs) used in standard LCD televisions. LED Television are also known as LED-backlight LCD TV.

An LED is a semiconductor device that release visible light when an electric current passes through it. The light is not especially bright, but in most LEDs it is monochromatic, happening at a single wavelength. In comparison with fluorescent lights, LEDs have significantly lower power needs and convert power to light more efficiently so that less is lost as heat and focus it more exactly so that there is less light leakage, which can cause fuzziness. An LED also remain much longer than most other lighting technologies.

There are three different LED technologies used. The most frequently used of the three is edge-lit LED, in which white LEDs are situated around the edge of the screen and a diffusion panel employed to illuminate the display evenly. Edge-lit LED displays can be very thin. Another type is dynamic RGB LED, which are put behind the panel. RGB LEDs make it possible to target areas for dimming more exactly, which in turn leads to truer copying of blacks and whites. In the third type of display, full-array LED, LEDs are positioned behind the panel similarly to the way they are with RGB LED displays but there is no volume for localized dimming.

Quantum dot-based LED displays, in the research stage, are expected to enable LED TVs that will rival plasma for picture quality, and maybe even OLED.

Vendors of LED TVs include Kogan, LG, Panasonic, Philips, ProScan, Samsung, Toshiba and Vizio.

Pros: Use less power and make less heat than plasma or other LCD TVs. RGB LED: Brighter, sharper display and greater contrast ratio than other LCD TVs. Edge-lit LED: Thinner format.

Cons: More costly than plasma or other LCD TVs.

What is 4K resolution? Our guide to Ultra HD viewing

4K Ultra HD: the resolution offering you more pixels than ever in your home television.

Remember when Full HD appear like the sharpest picture you could get? With four times as more pixels as HD, 4K resolution has completely changed the level of visual detail and clarity we’ve come to expect from our screens.

Whereas traditional HD is limited to 1920 vertical columns and 1080 horizontal rows of pixels, Ultra HD has a total resolution of 3,840 pixels by 2,160 – a bit smaller resolution than the 4,096 x 2,160 pixels spot on most cinema screens (that, for the record, is called Cinema 4K).

It’s pretty hard these days to get a TV that isn’t 4K, with even budget small TVs opting for the detailed resolution to entice viewers – and the truly premium sets out there opting for 8K resolution instead. With Black Friday and Cyber Monday around the corner, too, catch a new 4K TV among the best Black Friday TV deals could well be on your agenda.

There’s no doubt about it: 4K Ultra HD is now the industry standard for television panels, with the increased detail posture even more fruit at larger television sizes where you’re able to see the difference more clearly.

At the end of the day, though, it might not be the raw resolution of 4K that induce you into your next TV purchase, but the addition of other cool technologies like High Dynamic Range (HDR), Quantum Dot and OLED panels.

Before we get into the state of each technology, here’s a video outlining 4K in a nutshell.

What is 4K?

Perfect and simple, 4K means a clearer picture. It’s more pixels (8,294,400 to be exact) on the screen at once that creates images that are hard and capable of showing more details than standard HD.

What is the resolution of 4K?

4K resolution, at least the way most TVs explain it, is 3840 x 2160 or 2160p. To place that in perspective, a full HD 1080p image is only a 1920×1080 resolution. 4K screens have about 8 million pixels, which is around four times what your current 1080p put can display.

Think of your TV like a mesh, with rows and columns. A full HD 1080p image is 1080 rows high and 1920 columns wide. A 4K image roughly doubles the numbers in both directions, yielding approximately four times as many pixels total. To place it another way, you could fit every pixel from your 1080p set onto one quarter of a 4K screen.

4k vs Ultra HD: What’s the difference?

4K is more frequently used, but you’ll also find people calling it Ultra HD, or UHD. For the standard customer buying a TV, these are one and the same. But there is a little difference.

In its correct usage, true 4K refers to a resolution of 4096 x 2160, which was first establish in digital cinemas. UHD refers to a resolution of 3840 x 2160, which is the resolution you literally get on the TVs you take home.

So technically, 4K is the wrong word for 3840 x 2160 displays and content, but it’s said so often that two words are interchangeable.

What does 4K offer?

Simply, the more resolution of 4K adds finer definition and clarity. The result is images that look life-like, closer to looking through a window rather than watching TV.

4K TV is mostly effective on very large screens – so ideally you’d sort out for a 55-inch set or go even bigger. The effect is more visible if you’re moving to 4K from a TV of the same size.

Let’s say you have a 50-in HD TV and you upgrade to 4K: you are pack four times the number of pixels into the same amount of space and that makes for a visible denser picture with better detail.

8K has hit the market, although it’s still in its infancy there are 8K screens available to buy. They are, expensive, however, and will required a screen of at minimum 65in to get the best out of them. There’s also no native 8K content to watch at the moment.

8K won’t reach mainstream acceptance (or affordability) for a while yet, so you’re safe to buy your 4K TV unless you’re hopeless for the features that 8K brings with it.