4K resolution(分辨率)

4K resolution

4K resolution, also called 4K, refers to a horizontal resolution in the order of 3840 (or 4096) pixels and vertical resolution in the order of 2160 pixels.[1]
Several 4K resolutions exist in the fields of digital television and digital cinematography. In the movie projection industry, Digital Cinema Initiatives (DCI) is the dominant 4K standard. In television and consumer media, 4K UHD or UHD-1 is the dominant 4K standard. By 2015, 4K television market share had increased greatly as prices fell dramatically during 2014[2]
and 2015. By 2025, more than half of U.S. households are expected to have a 4K-capable TV (2160p), which would be a much faster adoption rate than that of Full HD (1080p).[3]

4K分辨率主要有两个标准:
The DCI 4K(分辨率:4096 * 2160)和UHD-1(分辨率:3840 * 2160)。

• The DCI 4K

The DCI 4K resolution standard, which has a resolution of 4096 × 2160 pixels (256:135, approximately a 1.9:1 aspect ratio). This standard is widely respected by the film and video production industry.[5]
The DCI 4K standard has twice the horizontal and vertical resolution of DCI 2K.

主要用于电影院。

• UHD-1

UHD-1, or ultra-high-definition television (UHDTV), is the 4K standard for television and computer monitors. UHD-1 is also called 2160p[6]
[7]
since it has twice the horizontal and vertical resolution of 1080p.[6]
It has a resolution of 3840 × 2160 (16:9, or approximately a 1.78:1 aspect ratio). UHD-1 is used in consumer television and other media, e.g. video games.

主要用于普通消费者。

DCI 4K(`4096*2160`) 与UHD(`3840*2160`) 比较示意

注:
2160是1080的2倍
3840是1920的2倍
4096=1024*4

4K

可以看出 The DCI 4K和 UHD 4K大约为 800万像素。

References:

https://en.wikipedia.org/wiki/4K_resolution