Patent ID: 8194049

Claim:
A capacitive motion detection device comprising: a device main body; two or more detection electrode/drive electrode pairs in each of which a capacitance is formed between a detection electrode and a drive electrode, the detection electrode/drive electrode pairs being provided at detection positions of the device main body; a motion detection circuit configured to detect motions of an object to be detected in two or more axis directions from a variation in a capacitance obtained in each of the detection electrode/drive electrode pairs, the motion detection circuit including a drive circuit and a detection circuit; and a switching circuit configured to selectively coupling the drive circuit and the detection circuit to the detection electrode/drive electrode pairs, wherein the device main body includes a substantially rectangular first area having four sides, the detection electrode/drive electrode pairs including: first and second electrodes disposed on first two opposing sides of the first area; third and fourth electrodes disposed on second two opposing sides of the first area; and a fifth electrode disposed outside the first area, and wherein the switching circuit is configured to: connect the third and fourth electrodes to the drive circuit and the first and second electrodes to the detection circuit such that the motion detection circuit detects a motion of the object in a first axis direction; connect the first and second electrodes to the drive circuit and the third and fourth electrodes to the detection circuit such that the motion detection circuit detects a motion of the object in a second axis direction crossing the first axis direction; and connect the first, second, and fifth electrodes, or the third, forth, and fifth electrodes, to the motion detection circuit such that the motion detection circuit detects a motion of the object in a third axis direction crossing the first axis direction and the second axis direction.