Determining forces of contacts between styluses and objects

摘要

An apparatus comprising a stylus with a dynamically switch tip shield is provided. The apparatus includes an elongated stylus housing having an end, a conductive tip disposed at least partially inside the stylus housing and extending from the end, a force sensor coupled to the conductive tip and configured to detect contact between the conductive tip and an object, a tip shield coupled with the stylus housing and extending from the end, and a switch coupled to the tip shield and the conductive tip. The force sensor may be an inductive sensor, a capacitive sensor, a piezo sensor, a force sensing resistor sensor, or an optical sensor.

主权项

1. An apparatus comprising:
a stylus housing having an end; a transmit (TX) drive circuit disposed at least partially inside the stylus housing; a tip shield configured to be coupled to the TX drive circuit to receive a TX potential from the TX drive circuit; a conductive tip disposed at least partially inside the stylus housing and extending from the end, the conductive tip configured to receive the TX potential from the TX drive circuit and capacitively couple a transmit signal to a sense array when the tip shield is coupled to the TX drive circuit, when the tip shield is not coupled to the TX drive circuit, and without a change in contact between the conductive tip and a touch surface; a force sensor coupled to the conductive tip and configured to measure a force of a contact between the conductive tip and the touch surface; and a switch configured to electrically couple the tip shield to the conductive tip when the measured force of contact indicates that the conductive tip is not in contact with the touch surface.