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William M Louis: Membrane keyboard and method of using same. TypeRight Keyboard, Bernard L Kleinke, Jerry R Potts, William Patrict Waters, May 18, 1993: US05212473 (339 worldwide citation)

A membrane keyboard producing audible and tactile responses when individual character keys are depressed. To facilitate typing efficiency, the keyboard has membrane characters keys with different transverse heights and adjustable sensory responses.


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William M Louis: Ergonomic keyboard apparatus with left and right key section separated by an irregularly shaped space. TypeRight Keyboard Corporation, Bernard L Kleinke, Jerry R Potts, December 13, 1994: US05372441 (91 worldwide citation)

A keyboard arrangement with a pair of angularly disposed, spaced apart groups of character keys dedicated for operating use respectively by the left hand and the right hand of a user. A space bar key is operable by either thumb of the user and bridges between the two groups of character keys. The ro ...


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William M Louis: Ergonomic keyboard apparatus and method of using same. Typeright Keyboard Corporation, Bernard L Kleinke, Jerry R Potts, Peter P Scott, April 2, 1996: US05503484 (81 worldwide citation)

A keyboard arrangement with a pair of angularly disposed, spaced apart groups of character keys dedicated for operating use respectively by the left hand and the right hand of a user. A space bar key is operable by either thumb of the user and bridges between the two groups of character keys. The ro ...


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Louis William M: Ergonomic keyboard apparatus and method of using same.. Typeright Keyboard, December 8, 1993: EP0572487-A1

A keyboard arrangement with a pair of angularly disposed, spaced apart groups of character keys (314, 316) dedicated for operating use respectively by the left hand and the right hand of a user. A space bar key (159) is operable by either thumb of the user and bridges between the two groups of chara ...


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Louis William M: Ergonomic keyboard apparatus and method of using same. Typeright Keyboard, KLEINKE Bernard L, September 3, 1992: WO/1992/014612

A keyboard arrangement with a pair of angularly disposed, spaced apart groups of character keys (314, 316) dedicated for operating use respectively by the left hand and the right hand of a user. A space bar key (159) is operable by either thumb of the user and bridges between the two groups of chara ...


8
Louis William M: Membrane keyboard and method of using same. Typeright Keyboard, KLEINKE Bernard L, September 3, 1992: WO/1992/015083

A membrane keyboard (10, 110) producing audible (94, 187) and tactile (80, 182) responses when individual character keys are depressed. To facilitate typing efficiency, the keyboard has membrane characters keys with different transverse heights and adjustable sensory responses (84, 184).


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Louis William M: Membrane keyboard and method of using same.. Typeright Keyboard, December 8, 1993: EP0572482-A1

A membrane keyboard (10, 110) producing audible (94, 187) and tactile (80, 182) responses when individual character keys are depressed. To facilitate typing efficiency, the keyboard has membrane characters keys with different transverse heights and adjustable sensory responses (84, 184).