Movie film has a resolution of ~7000 pixels/inch (~275 pixels/mm), if I remember rightly. Projection lowers the effective resolution as seen by the eye; sitting farther away from the screen increases it.
Common computer displays have a resolution of 75 or 100 (3 or 4 pixels/mm) pixels per inch.
My laptop has a display with 135 pixels per inch (5 pixels/mm). It also displays quite well at an angle: that is why I got it, so people could look over my shoulder.
Interestingly, I find the higher resolution to be much more significant than I expected. Text and pictures look sharp. The display is still not as crisp as I would like, but it is dramatically better than the lower resolution.
There is a difference between viewing a self-illuminating display such as a computer screen and a display that requires reflected light, such as a printed page. Some years ago, I noted that the minimum comfortable resolution for plain black text on white paper is 300 dots per inch (12 dots per mm). Traditionally, newspaper pictures had a resolution of 150 dots per inch (6 dots per mm). They look grainy. But with the quality of newsprint, that is probably a good resolution.
Designers create type faces to match the quality of paper. Thus, `Century Schoolbook' with its square serifs, prints well on low quality paper. The `modern' typefaces have more elongated serifs than the `traditional' designs — over the past two centuries, ordinary paper has got better. (However, for I prefer the traditional designs, even on high quality paper. I am old fashioned.)
600 dots per inch (24 dots per mm) is much better than 300 dpi, at least for text. Conventional printing runs often runs at 1200 - 1800 dots per inch (47 - 71 dots per mm); high quality printing has an even better resolution.
I sit about 21 inches (a bit more than 50 cm) from my screen (I just measured it). This means that each pixel is subtending roughly 1/2835 of a radian or about 1.2 arcminutes on my 135 pixels per inch (5 pixels/mm) display.
A few years ago in my airplane I noted how far away I could see the tower on top of a local mountain. If I rememeber rightly, I figured I could see the tower as a small vertical line when it subtended 1/3000 of a radian sideways, which is a bit more than 1 arcminute.
Traditionally, astronomers have said that a human eye can distinguish two stars that appear to the eye to be more than 1 arcminute apart.
I hold books more closely than I sit from my computer screen — round about 16 inches (40 cm) from my eyes. I do not know what distances most people use. But for a text with a resolution of 1200 dots per inch, at a distance of 16 inches, a dot or edge has a fuzziness of roughly 1/20000 of a radian or 10 arcseconds. That starts looking pretty good.
My hunch is that people will seek crisper displays until they reach that kind of resolution. Over the next generation or so, and perhaps more quickly, we should see an increase in sharpness that amounts to 6 to 12 times the contemporary resolution.
15 inch (~40 cm) displays will grow from 1024x768 pixels to 6000x4500 or 12000x9000 pixels.
(It goes without saying that multicolored printed requires that the various plates be registered very accurately; otherwise, you will see ugly artifacts.)
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