Stylus input device utilizing a permanent magnet

Abstract

A stylus that operates utilizing magnetic fields, wherein a permanent magnet is disposed within a passive stylus that is detectable by a plurality of magnetic sensors that remove the magnetic field of the stylus from the earth's relative magnetic field to thereby obtain vectors that are used in a triangulation equation to determine the location of the stylus in two or three dimensions, depending upon the number of magnetic sensors that are used, wherein one set of magnetic sensors can be used as a reference for earth's magnetic field, and wherein each of the magnetic sensors includes a polarizing coil to change direction of sensitivity, a null coil and a flipping coil.

What is claimed is:  
     
         1 . A passive stylus system for providing input to an electronic appliance, wherein the passive stylus utilizes a permanent magnet to provide location information to a magnetic sensor system, said passive stylus comprising: 
 a passive stylus including at least one permanent magnet;    a magnetic sensor system for detecting a location of the at least one permanent magnet disposed within the passive stylus, wherein the magnetic sensor system further comprises a plurality of magnetic sensors that are capable of (1) detecting the at least one permanent magnet, (2) determining a location of the at least one permanent magnet relative to a reference point, and (3) transmitting the location of the at least one permanent magnet; and    a display system, wherein the display system utilizes the location of the at least one permanent magnet to display data on the display system that represents movement of the passive stylus within a field of operation.    
     
     
         2 . The passive stylus system as defined in  claim 1  wherein the magnetic sensor system further comprises at least two magnetic sensors that provide x and y coordinate information.  
     
     
         3 . The passive stylus system as defined in  claim 2  wherein the system further comprises utilizing a circular triangulation formula for determining a location of the passive stylus, wherein data from the at least two magnetic sensors is utilized in the circular triangulation formula to reduce inaccuracies in passive stylus position determination due to inclination or movement of the passive stylus.  
     
     
         4 . The passive stylus system as defined in  claim 3  wherein the passive stylus further comprises: 
 a stylus body for housing components of the passive stylus;  
 an ink cartridge;  
 an actuator disposed on a non-inking end of the ink cartridge;  
 at least one position magnet disposed adjacent to an inking end of the ink cartridge, having a hole through which the ink cartridge is disposed;  
 a spring disposed around the ink cartridge, and between the at least one position magnet and a stylus tip;  
 a trigger magnet disposed above a non-inking end of the ink cartridge, and having a hole through which the actuator can pass;  
 a ferrous washer disposed above the trigger magnet, the ferrous washer having an outer shelf and an inner conical depression in a surface thereof;  
 a signaling magnet disposed at rest so as to be inclined, a bottom surface disposed at least partially at rest against the inner conical depression, wherein the ink cartridge will push the signaling magnet from an inclined position to an upright position so that the bottom surface of the signaling magnet is at least partially at rest against the outer shelf.  
 
     
     
         5 . A method for providing input to an electronic appliance utilizing a stylus system that incorporates a permanent magnet, said method comprising the steps of: 
 (1) providing a stylus body having a permanent magnet associated therewith, and a magnetic sensor system;    (2) detecting the permanent magnet utilizing the magnetic sensor system;    (3) determining a location of the permanent magnet relative to a reference point; and    (4) transmitting the location of the permanent magnet in the stylus body.