Patent ID: 8587527

Claim:
A coordinate input device, comprising: a pressure-sensitive sensor for detecting a coordinate position input defined by coordinates regardless of an amount of pressure imparted upon said pressure-sensitive sensor and obtaining a first input value indicative of the coordinate position input as detected by the pressure-sensitive sensor; an electromagnetic-induction sensor for detecting the position input defined by coordinates and obtaining a second input value indicative of the position input as detected by the electromagnetic-induction sensor, the pressure-sensitive sensor and electromagnetic-induction sensor configured to permit simultaneous detection of the position input and to simultaneously obtain the first and second input values, the electromagnetic-induction sensor having a tendency to be a more accurate indication of the position input than the pressure-sensitive sensor; a position indicator configured to simultaneously perform the position input on the pressure-sensitive sensor and the electromagnetic-induction sensor; a determining unit configured to determine whether the position indicator performs the position input on the pressure-sensitive sensor and electromagnetic-induction sensor to simultaneously obtain coordinates of the first input value and the second input value, respectively; a difference detecting unit to detect a difference value between the coordinates of the first input value and the second input value when the determining unit determines that the position indicator performs the position input on the pressure-sensitive sensor and electromagnetic-induction sensor to simultaneously obtain coordinates of the first input value and the second input value, respectively; a storing unit configured to store the difference value as correction information; and a correcting unit configured to correct the first input value using the stored correction information, the corrected first input value used as the coordinate position input when the second input value is not obtained, wherein said storing unit updates the correction information in real time to account for degradation in performance of the pressure-sensitive sensor that occurs with repeated use of the pressure-sensitive sensor.