Patent ID: 7248251
Filing Date: 2007-07-24
Classification: G06F

Abstract:
1. A stylus comprising: a stylus tip; a first ultrasonic transmitter controllable by application of pressure to the stylus tip; a second ultrasonic transmitter; a first switch to control the second ultrasonic transmitter; and a higher frequency transmitter to provide a time reference for the first and second ultrasonic transmitters; wherein the stylus is to use with a wireless display system having a projection plane and at least three ultrasonic receivers, wherein the first ultrasonic transmitter is to transmit ultrasonic energy to at least two of the ultrasonic receivers in determining a position of the stylus relative to the projection plane in two dimensions, and wherein the second ultrasonic transmitter is to transmit ultrasonic energy to at least three ultrasonic receivers in determining a position of the stylus relative to the projection plane in three dimensions.