US 7,248,251 B2 · Wireless display systems and stylii

Abstract

A wireless coordinate input system for a display system includes a stylus that transmits ultrasonic energy to a plurality of ultrasonic receiving stations in a projection plane. In an embodiment, the stylus may include one ultrasonic transmitter used for determination of three-dimensional coordinates of the stylus relative to the projection plane. The stylus may also include a second ultrasonic transmitter controlled by a pressure-activated switch. When the stylus is pressed against the projection plane, the second transmitter turns on and is used for determination of two-dimensional coordinates of the stylus in the projection plane. The stylus may also include a higher frequency burst transmitter used to generate a time reference. One or more of the ultrasonic receiving stations may also include an ultrasonic transmitter for calibration.

Claims23

Dependent claims

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.

4 more elements

Dependencies are inferred from the claim text.

Wireless display systems and stylii

Life of this patent

Wireless display systems and stylii

Life of this patent

Abstract

Claims23