抄録
Purpose of the study was to find out better key shapes as input devices with tactile detection of hand. Eight male students volunteered as subjects. They were right handed. Shapes of circle, square, triangle, sexangle, plus, and minus were randomly presented one by one. Subjects answer the detected shape as possible using only left hand. Size and thickness of circle, square and triangle keys were changed. As the results, key of minus shape was the best for tactile detection. Triangle key was better than square one. Regarding key size and thickness, minimum circumference of key was 18 mm, minimum thickness of key was 0.4 mm for circle, square and triangle keys.