Reading text on a lighted display has become part of our daily routine. Web fonts have established themselves, and more and more content is read on tablets or mobile devices. This raises the bar on font quality on different displays. Nonetheless, most fonts used today were not designed for a digital environment. Font drafts from pre-digital times are often optimized for onscreen usage using technological means, like hinting, for example. But onscreen optimization has to start much earlier!
I have compiled a few characteristics that improve the readability on screens. When looking for a well-made font for onscreen texts, pay attention to these aspects:
Open Counters, Generous Tracking (Fonts Left to Right: Tuna, Garamond, Arial and Fira)
For small font sizes, counters, the non-printing insides of the letters, quickly fill up, creating dark spots in the font’s gray level, capturing the reader’s attention, and thus, hindering the reading flow. To keep the non-printing white spaces visible on small font sizes, as well as allowing for a well-visible light incidence, open apertures, and a large x-height in relation to the ascenders are helpful.
Generous Tracking and Wide Letters
Pay attention to the pitches! Tight, slim fonts are suitable for headings and high font sizes, but fonts need more space in a running text. The individual characters need to be wider, in order for the white space within a glyph to be large enough. Generous pitches avoid clashes between the characters, while clear word spaces ease the forming of word groups when reading quickly.