Patent ID: 8878824

Claim:
A force-sensitive stylus comprising: a housing; a first electromagnetic coil located at a fixed position within the housing; a compliant element; a tip element extending from one end of the housing and moveably coupled to the housing by the compliant element; a second electromagnetic coil attached to the tip element and positioned to interact with the first electromagnetic coil, the position of the second electromagnetic coil relative to the first electromagnetic coil dependent upon a force applied to the tip element; and a control circuit operable to: energize a transmitting coil of the first and second electromagnetic coils with a radio frequency signal; sense a signal associated with a receiving coil of the first and second electromagnetic coils and determine the force on the tip element, and encode the determined force in the radio frequency signal, wherein the transmitting coil is operable to both excite the receiving coil and communicate the force to a host electronic device.