Patent ID: 8130212

Claim:
A contact-sensing device, comprising: a capacitance contact-sensing unit including a plurality of contact-sensing areas configured to at least detect contact with an external object; a calibration-value setting unit configured to set a calibration value to be used to calibrate capacitances of the contact-sensing areas based on capacitance values of each of the contact-sensing areas excluding a contact-sensing area, of the plurality of contact-sensing areas, that has been detected by the capacitance contact-sensing unit to be in contact with the external object; a calibration determining unit configured to determine whether or not calibration of the capacitances of the contact-sensing areas is to be carried out based on capacitance values of the contact-sensing areas excluding the contact-sensing area that has been detected by the contact-sensing unit to be in contact with the external object; and a capacitance calibrating unit configured to calibrate capacitances of all of the contact-sensing areas using the calibration value set by the calibration-value setting unit when the calibration determining unit determines that calibration is to be carried out, wherein the capacitance contact-sensing unit detects whether or not a contact-sensing state continues for a predetermined amount of time in the contact-sensing area detected to be in contact with the external object; and the calibration-value setting unit sets the calibration value and the calibration determining unit determines whether or not calibration is to be carried out, when the capacitance contact-sensing unit detects that the contact-sensing state is continued for the predetermined amount of time.