The highest display resolution of the UN40JU6700 is 4K Ultra HD. That's over four times the display resolution of a Full HD TV, which is the most common display resolution. 4K Ultra HD TVs have a resolution of 3840 x 2160 pixels.
This TV's display resolution (4K Ultra HD) is in fact the best display resolution across all similar spec TVs that have been on the market for a comparable time to the UN40JU6700.
The worst display resolution amongst similar types of TV is HD Ready.
4K Ultra HD TVs have a resolution of 3840 x 2160 pixels.