PEN TYPE INPUT DEVICE

摘要

PROBLEM TO BE SOLVED: To accurately detect the tilt of the device and perform accurate writing detection when the detection result of writing input is inaccurate because of the tilt of the device. SOLUTION: A stationary state decision part 47 decides a stationary sate from the difference between the composite vector of acceleration detected by an acceleration sensor 2 (2a-2e) and gravitational acceleration and an initial tilt angle arithmetic part 45 calculates the initial tilt angle of a penholder on the basis of the acceleration detected by the acceleration sensor 2. A tilt angle variation arithmetic part 46 calculates variation in the tilt angle of the penholder on the basis of a rotational angular velocity detected by a gyro 3 (3a-3c), and an in-writing tilt angle arithmetic part 48 calculates the tilt angle of the penholder on the basis of those values. A coordinate conversion arithmetic part 49 converts the coordinate system of the acceleration detected by the acceleration sensor 2 to a gravitational coordinate system on the basis of the tilt angle of the penholder in writing operation.