Computer input device with two cursor positioning spheres

Claim 1

An input device for moving a cursor on a computer display screen, said input device comprising (a) a keyboard, having a plurality of rows of depressible type keys oriented for general operation of said keyboard from an operator side of said keyboard, one of said rows containing home keys to which a user's hands normally return while operating said input device; (b) a first cursor positioning sphere rotatably mounted on said keyboard between said rows of type keys and said operator side of said keyboard to permit manual rotation of said first sphere by a thumb of the user while the user's fingers remain in contact with said home keys; (c) first sensing means connected with said first sphere for sensing the rotation thereof, said first sensing means generating first and second output signals corresponding with the magnitude and direction of the sensed rotation with respect to first and second perpendicular axes of said first sphere, respectively; (d) a second cursor positioning sphere rotatably mounted on said keyboard between said rows of type keys and said operator side of said keyboard to permit manual rotation of said second sphere by a thumb of the user while the user's fingers remain in contact with said home keys; (e) second sensing means connected with said second sphere for sensing the rotation thereof, said second sensing means generating third and fourth output signals each corresponding with the magnitude and direction of the sensed rotation with respect to first and second perpendicular axes of said second sphere, respectively, said first, second, third, and fourth output signals controlling the position of said cursor on the display screen, respectively, said first, second, and third output signals controlling cursor movement on the display screen along the X, Y, and Z axes, respectively, of the screen.