Screen resolution is the number of pixels (dots) on the screen, regardless of the physical size of screen. For example, a 60″ screen could present any of the following resolutions:
- 2K = 1920 x 1080 (aka HD or 1080)
- 4K = 3840 x 2160
- 5K = 5120 x 2160
- 8K = 7680 x 4320
- 10K = 10240 x 4320
The graphic below give you a sense of what would be shown on the screen at different resolutions. Remember that the physical size of the screen is not key. What is important is the number of dots, or pixels:
It is the number of “vertical lines” by the number of “horizontal lines” of pixels that really counts. When you start doing the math the numbers get big quickly. For instance, there are 2.1 million (1920 x 1080) pixels on a typical screen today. 4K screens have 8.3 million (3840 x 2160) pixels. This means the process to produce the screens and the costs associated with them are substantially different.
Note the tiny little box in the top left corner labeled 480 x 480 STANDARD. That is what North American TV was until about the year 2000 when 720 (not shown) and 1080 (2K) became the standards. That means we used to look at screens that showed a mere .23 Million (480 x 480) pixels.
That is why when you show old content on a new screen it looks fuzzy; the screen makes the image larger by using more pixels to show the same image.
That is also why people often say they cannot see a difference between the various high resolution standards; the images are already shown with millions of dots making them super crisp. You need to get to a physically very large screen to see the difference between a 4K screen and a 10K screen.