When searching for free-licensed fonts for a project, I've found that a lot of fonts looks pale and thin on screen, unless enlarged to a very big size. Others are dark enough, but somewhat blurred. Theirs glyphs don't have homogeneous black color with sharp outlines which distinguishes them from the background.
At the picture above [[http://www.megaupload.com/?d=6W0D0HSM|(at the file I've uploaded to this link it is much more obvious to see)]], only line 3 (DejaVu Sans) and 5 (Arial) are clear and sharp.Lines 1 and 2 are blurred, and line 4 is blurred and also not dark enough.
So I would like to ask what makes some fonts sharper then others, and weather making a font to look sharper on screen involved a lot of work.