SENSING DEVICE HAVING CAPACITIVE FORCE SENSOR

摘要

A sensing device is provided for interacting with a substrate. The sensing device has a force sensor for detecting whether the sensing device is interacting with the substrate and an image sensor for sensing coded data disposed on the substrate. The force sensor has a capacitive sensor circuit incorporating a sensor capacitor having variable capacitance C_sen arranged so that an output of the capacitive sensor circuit is proportional to 1/C_sen.