INTERACTION DESIGN PRINCIPLES FOR INTERACTIVE ...

Tom Buehler provides a helpful tutorial on making computer graphics NTSC
compliant, and addresses issues related to luma values, color values, lines and edges, as
well as safe zones (2003).
4.2.6 Typography
Text poses difficult challenges on television screens, as viewers are not
accustomed to reading static blocks of text on screen. Other contributing factors include
poor display quality of still images, the difficulty of rendering detail at low screen
resolutions, color bleeding, and interlacing flicker. At the same time, the relatively large
text size required for legibility on a television screen makes it difficult for designers to
create effective screen layouts.
As a general rule, fonts must be used with care. Very light weights or fonts with
very narrow and broad strokes should be avoided. It is a good idea to use simply
constructed sans-serif fonts and use anti-aliasing to increase readability (Quesenbery &
Reichart, 1996). Anti-aliasing, also known as smoothing, is a technique of blending
bitmap-based images and text to reduce the jagged appearance of aliased text. The
process of anti-aliasing blends the edge pixels in areas of transition to give the text a
smoother looking appearance.
BBC interactive television services use Tiresias, a typeface specifically developed
for television in conjunction with the Royal National Institute of the Blind, and adopted
as a standard by the UK Digital Television Group as the resident font for interactive
television (http://www.tiresias.org/fonts/design_report_sf.htm). This alphabet displays
well at small sizes, and functions when stretched or squashed by televisions attempting to
compensate for 4:3 or 16:9 ratios. Careful attention has also been paid to character
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