Patents Examined by Jolio Cesas Gonzalez
  • Patent number: 6476537
    Abstract: A method and apparatus for controlling a piezo-electric actuator coupled to a driven member is disclosed. The piezo-electric actuator is responsive to waveforms with asymmetrical voltage/current profiles on the rising and falling edge to effect consistent and cumulative movement of the driven member in one of two directions throughout the reciprocations of the piezo-electric actuator. The waveforms are digitally generated from a stored set of numbers or a function for generating the set of numbers. The numbers correspond with the discrete digital values associated with the desired waveforms for moving the driven member in either of at least two directions. The controller may be used to drive more than one piezo-electric actuator. The controller may include responsiveness to a feedback of the position of the driven member to accurately position the driven member.
    Type: Grant
    Filed: November 3, 2000
    Date of Patent: November 5, 2002
    Assignee: New Focus, Inc.
    Inventors: John Pease, Sherwin D. Cabatic, Dennis E. Melvin