Intercharacter Spacing of Screen Fonts

[Peter Olcott]

Applications such as Microsoft Word have inconsistent intercharacter spacing of
their screen fonts. I initially thought that this pertained to kerning.
Apparently it does not. I am trying to understand what is going on. The pixel
spacing between any two characters seems to vary here and there by one pixel. My
current best guess is that MS Word is trying to map the on screen representation
to the printed layout. Since there are rounding errors when any font is produced
in the relatively low resolution on the screen, the inconsistent character
spacing must be an attempt to account for these rounding errors. Does this seem
correct?

Can anyone please provide any further insight?

Thanks

 

[Jezebel]

This has nothing much to do with Word: it's a computer issue in general.
It's a branch of digital typography known as 'hinting', and your
understanding of it is pretty well correct. The challenge is to get
consistent rendering on screen (as you say, at low resolution compared to
printing), for any combination of type size and screen zoom. Amongst other
effects, characters may need to be shifted left or right a little so that,
for example, all vertical strokes have the same weight.

Some fonts have had a lot more hinting work done on them than others. If you
experiment with different fonts at different sizes, you'll see that some of
them display reasonably well over quite a range of sizes, while others look
really terrible at some sizes.