Was ist ein 4K (Ultra HD)?
TVs are getting bigger and resolution is getting higher. 4K TVs are now the standard, and if you haven't upgraded from your 1080p HDTV yet, here's what you need to know.
It's a 4K World
We're well into the age of 4K now. HDTVs with 1,920-by-1,080 resolutions have been effectively placed with bigger, brighter 4K TVs with four times as many pixels. 4K has gone through its early steps and various growing pains for early adopters and is now solidly mainstream as the standard type of TV you can buy. You can find 4K TVs in all sizes and prices, including 65-inch models for well under $1,000. If you haven't made the jump to 4K yet, this is a good time to do it. Here's what you need to know.
A 4K display is one with at least 8 million active pixels. For televisions, that resolution has standardized to 3,840 by 2,160. Digital cinema 4K (the resolution in 4K movie theaters) is slightly higher at 4,096 by 2,160. However you define it, it's four times the number of pixels on a 1080p display, and over 23 times the resolution of standard-definition television.
This means 4K is obviously much sharper than 1080p. In the space that a 1080p TV holds a pixel, a 4K TV of the same size can hold four. That makes for a significant jump in clarity, assuming you have native 4K source material to watch in that resolution. Even if you don't, companies like LG, Samsung, and Sony have developed impressive upconverting technologies that scale 1080p and lower resolution content to 4K with various image enhancements. It isn't as good as native 4K content because you can't simply synthesize additional detail out of nothing, but it's a good backup.
Because the resolution is much higher, it requires more bandwidth to transmit. The HDMI 2.0 standard was developed to support 4K and allows 2160p video to be displayed at 60 frames per second. This was initially a concern as HDMI 2.0 was becoming more commonplace, but right now you can count on nearly any home entertainment device you buy to support HDMI 2.0, and based on our tests you'd have to really go junk shopping to find an HDMI cable that can't transmit a 4K60 HDR picture. You can also stream 4K video over the internet, which similarly requires a fast connection; Netflix recommends a steady 25Mbps downstream speed to watch 4K content over its service.