Abstract: A low-cost x-y digitizing system for use in consumer electronic devices, such as portable digital assistants, mobile telephones, web browsers and the like. The digitizer includes a resonant stylus, an excitation winding for energizing the resonant stylus and a set of sensor windings for sensing the signal generated by the stylus, from which the x-y position of the stylus is determined. A novel stylus design is described together with novel digitizer windings and novel excitation and processing circuitry.

Abstract: A low cost x-y digitizing system is described for use in consumer electronic devices, such as portable digital assistants, mobile telephones, web browsers and the like. The digitizer includes a resonant stylus, an excitation winding for energizing the resonant stylus and a set of sensor windings for sensing the signal generated by the stylus, from which the x-y position of the stylus is determined. A novel stylus design is described together with novel digitizer windings and novel excitation and processing circuitry.

Abstract: A position detector is provided for detecting the relative movement of first and second members which are mounted for relative movement along a measuring path. One of the members comprises a magnetic field generator for generating a magnetic field and the other member comprises first and second conductors which are inductively coupled to said magnetic field generator. The arrangement of the first and second conductors and the magnetic field generator is such that output signals are generated in a first and second receive circuits whose position varies with the relative movement between the two members. In addition to carrying information relating to the relative position between the two members, the signals induced in the receive circuits also comprise information defining the relative orientation of the two movable members, and by suitable processing of the received signals the relative orientation of the two members can also be determined.

Abstract: A low cost x-y digitising system is described for use in consumer electronic devices, such as portable digital assistants, mobile telephones, web browsers and the like. The digitizer includes a resonant stylus, an excitation winding for energising the resonant stylus and a set of sensor windings for sensing the signal generated by the stylus, from which the x-y position of the stylus is determined. The excitation signals applied to the excitation winding are designed to reduce the power drawn from the power supply which makes the digitising system particularly suited to battery operation.

Abstract: A low cost x-y digitising system is provided for use in consumer electronic devices, such as portable digital assistants, mobile telephones, web browsers and the like. The digitiser includes a resonant stylus, an excitation winding for energising the resonant stylus and a set of sensor windings for sensing the signal generated by the stylus, from which the x-y position of the stylus is determined.

Abstract: A method of manufacturing a transducer used in sensing or generating magnetic fields in a position detector wherein the transducer has a substrate and a conductor fixed to the substrate in a predetermined pattern. A wire laying device controllably lays wire onto the substrate so as to form the predetermined pattern. Relative movement is caused between the laying device and the substrate, and the wire is bonded to the substrate as it is laid thereon.

Abstract: A rotary position detector includes first and second members, the first member generating a magnetic field which spatially varies around the axis of rotation in a cyclic manner and the second member sensing the generated magnetic field. In response to the generated magnetic field, first and second signals are generated by first and second sensors respectively, which signals vary with the relative angular position of the first and second members and the relative angular position of the first and second members is determined from the first and second signals.

Abstract: A position detector is provided for detecting the relative movement of first and second members which are mounted for relative movement along a measuring path. One of the members comprises a magnetic field generator for generating a magnetic field and the other member comprises first and second conductors which are inductively coupled to said magnetic field generator. The arrangement of the first and second conductors and the magnetic field generator is such that output signals are generated in a first and second receive circuits whose position varies with the relative movement between the two members. In addition to carrying information relating to the relative position between the two members, the signals induced in the receive circuits also comprise information defining the relative orientation of the two movable members, and by suitable processing of the received signals the relative orientation of the two members can also be determined.

Abstract: An electric motor is described in which a position sensor is provided which generates a plurality of output signals each dependent upon the relative position of the rotor and the stator. These signals are processed to generate a set of commutation control signals for controlling the commutation of the drive current to the stator coils. In one embodiment, a phase shift can be electronically applied to each of the position sensor coils to adjust the timing of the switching in accordance with the motor's current speed and load demands. In another embodiment, these signals are also used in a servo-control loop, in order to control, for example, the speed and/or output torque of the motor.

Abstract: A position detector is provided for detecting the relative movement of first and second members which are mounted for relative movement along a measuring path. One of the members comprises a magnetic field generator for generating a magnetic field and the other member comprises first and second conductors which are inductively coupled to said magnetic field generator. The arrangement of the first and second conductors and the magnetic field generator is such that output signals are generated in a first and second receive circuits whose position varies with the relative movement between the two members. In addition to carrying information relating to the relative position between the two members, the signals induced in the receive circuits also comprise information defining the relative orientation of the two movable members, and by suitable processing of the received signals the relative orientation of the two members can also be determined.