TYPABILITY OPTIMIZED AMBIGUOUS KEYBOARDS WITH REDUCED DISTORTION

It has been discovered how to make novel ambiguous keyboards which are both a) sufficiently typable to be attractive to expert users, and b) sufficiently similar to conventional keyboards [330] to be attractive to novice users. In general, unambiguous conventional keyboard [330] layouts make poor text-entry devices when straight-forwardly reduced in size. The straight-forward reduction involves reducing the number of keys and placing several letters on each of the keys whereby the keyboard [330] becomes ambiguous. The highly non-obvious engineering feat is to perform the reduction while maintaining a familiar look and feel, and without overly compromising text-entry capacity. The secret is to conceive of keyboards [330] which are a small perturbation of a conventional keyboard [330], choosing the perturbation adroitly so that typability is maximized.