Why can't the monitor display half a pixel?
Take the most common liquid crystal display (LCD) as an example to answer it.
Note: LED display is a kind of LCD
As shown in the figure, 3 (not necessarily, only the most typical) liquid crystal is a group, through the red, green and blue three primary colors of different proportions of light mixing, can produce the specific color we need. Such a group of liquid crystals as the smallest element of the display is considered to be a pixel point (such as the point on the right side of the graph).
Just like 1 dollar coins can not break apart in two halves to use, but two 5 cents equals 1 yuan. So if there is a demand to display the existing half pixel point, can only add one pixel to achieve.
So, what do you do if you don't want to add a pixel to the display of half a half or even one-fourth pixels? There is a way to achieve a higher pixel effect than actually dividing pixels. Image jitter. It belongs to the software level optimization method. The left side is the result of the jitter, the right is the image before the jitter.