Acoustic based pointing device

A system for moving a cursor on a display screen, comprising:

• a display device having the display screen;
• four microphones M1, M2, M3, and M4 at fixed positions such that no three of M1, M2, M3, and M4 are colinear;
• a wireless pointing device having an acoustic source, wherein the acoustic source is located at a position P0 having an associated position vector P0, wherein the acoustic source is adapted to generate and propagate an acoustic signal, wherein the microphone Mi is adapted to detect the acoustic signal, and wherein the acoustic signal detected at the microphone Mi is adapted to be converted to a periodic electrical signal Si, for i=1, 2, 3, and 4;
• a computing system to which the cursor, S1, S2, S3, and S4 are each electrically coupled, wherein the computing system is adapted to calculate P0 by solving triangulation equations that comprise a dependence on a phase-shift time delay between S1 and Sj, for j=2, 3, and 4, and wherein the computing system is adapted to compute a position vector PC for the cursor such that PC depends on:
• P0, a scale vector A, and a shape function of the display screen;
• and
• means for moving the cursor to a position PC associated with the position vector PC.

A pointing device, said pointing device being wireless and comprising an acoustic source at a position P0 having an associated position vector P0:

• wherein the acoustic source is adapted to generate and propagate an acoustic signal that can be detected by each of four microphones M1, M2, M3, and M4 at fixed positions such that no three of M1, M2, M3, and M4 are colinear;
• wherein the acoustic signal at the microphone Mi is adapted to be converted to a periodic electrical signal Si that is coupled to a computing system, for i=1, 2, 3, and 4;
• wherein the computing system is adapted to calculate P0 by solving triangulation equations that comprise a dependence on a phase-shift time delay between S1 and Sj, for j=2, 3, and 4;
• and
• wherein the computing system is adapted to compute a position vector PC for a cursor on a display screen such that PC depends on:
• P0, a scale vector A, and a shape function of the display screen.