Keypads Row Similar to a Telephone Keypad

An apparatus for inputting letters of a natural alphabetic language having a first array of a plurality of keys having a first layout of a plurality of said letters from a natural alphabetic language assigned to various of said keys with at least one of said keys having more than one of said letters thereon, said first array and said first layout being break similar to a second apparatus having a second array of a plurality of keys and a second distribution of a plurality of letters taken from the group of standard telephone keypads having substantially alphabetic ordering of letters and standard typewriter keyboards for said natural language.

Wherein said first layout meets both the even-as-possible constraint on a row-wise basis and the smoothness property.

An apparatus for inputting letters of a natural alphabetic language having an array of a plurality of keys having a layout of a plurality of said letters from a natural alphabetic language assigned to various of said keys with at least one of said keys having more than one of said letters thereon, said first layout meeting at least one constraint from the group a predetermined maximum of letters assigned to any one key and row-similarity, maximizing the number of isolated letters.

An apparatus for inputting letters of a natural alphabetic language having an array of a plurality of keys having a layout of a plurality of said letters from a natural alphabetic language assigned to various of said keys with at least one of said keys having more than one of said letters thereon, further comprising means for inputting digits, said means comprising either a digit key or a digit label interposed generally between an adjacent pair of keys.

An apparatus for inputting letters of a natural alphabetic language having a first configuration comprising a first array of a plurality of keys arranged over a predetermined columns and a first layout of a plurality of letters from a natural language assigned to various of said keys with at least one of said keys having more than one of said letters thereon, said first configuration and said first layout being row-similar to a second apparatus having a second array of a plurality of keys arranged over three columns and a second layout of a plurality of letters taken from the group of standard telephone keypads having substantially alphabetic ordering of letters and standard typewriter keyboards for said natural language, said first layout differing from said second layout in that, where there are more than one letter assigned to a key, said letters on said key are displayed on said key in a different order in said first layout as compared to said second layout.

An apparatus for inputting letters of a natural alphabetic language having a first array of a plurality of keys having a first layout of a plurality of letters from a natural language assigned to various of said keys with at least one of said keys having more than one of said letters thereon, said first array and said first layout being row-similar to a second apparatus having a second array of a plurality of keys and a second layout of a plurality of letters taken from the group of standard telephone keypads having substantially alphabetic ordering of letters and standard typewriter keyboards for said natural language, each of said keys being separated horizontally from an adjacent key by at least a first amount of negative space.

An apparatus for inputting letters of a natural alphabetic language having a first array of a plurality of keys having a first layout of a plurality of letters from a natural language assigned to various of said keys with at least one of said keys having more than one of said letters thereon, said first array and said first layout being row-similar to a second apparatus having a second array of a plurality of keys and a second layout of a plurality of letters taken from the group of pseudo-standard telephone keypads having substantially alphabetic ordering of letters and pseudo-standard typewriter keyboards for said natural language.