Computer input device with encoders having flexible shafts and conical rollers

A method and apparatus for replacing two separate photo detectors chips and two photo emitters by a single photo detector chip and a single photo emitter. This is achieved by using CombiDisks having a flexible shaft. The flexible section allows for the bending of the CombiDisks so that the encoder disks are next to each other and tangent to the same vertical plane. This allows for the placement of both the x and the y sensors in a single plane. This will in turn allow for the two photo detectors to be integrated in a single semiconductor chip, saving a separate photo detector chip, and its associated packaging. This additional savings is significant since the packaging itself contributes to approximately one half of the cost of such a detector.