Abstract: A Japanese character processing system containing a roman character keyboard containing a plurality of keys arranged in one or more rows. A first set of roman character consonants is provided in one row, a second set of roman character consonants is provided in a second row, and a set of roman character vowels is provided in a third row. The processing system converts a valid consonant-vowel combination into a corresponding Japanese character upon the entry of a valid consonant vowel combination and displays the Japanese character on a display device coupled to the processing system.

Abstract: A Japanese character processing system containing an on-screen keyboard which includes an array of base Japanese kana characters of a first kana character set. The first selection of a character key causes the display of the character in base kana form. A second consecutive selection of the same key causes the display of the character in a first variant form. Subsequent consecutive selections of the character cause the display of the character in further variant forms. Variant forms may include voiced, aspirated, or subscripted versions of the base character. A further variant form may include the display of the character in an alternate kana character set.