Patent ID: 7485106

Claim:
A phacoemulsification apparatus comprising: a phacoemulsification handpiece having a needle, having a tip, the needle configured to be ultrasonically vibrated; a power source configured to provide pulsed electrical power, having a power level, a pulse duty cycle and a drive voltage, to the handpiece; a foot pedal that enables a surgeon to select the power level of the pulsed electrical power; and a computer operatively coupled to the foot pedal, power source, and handpiece and programmed to control the power source by varying the pulse duty cycle of the pulsed electrical power supplied to the handpiece in accordance with the power level selected by the surgeon via the footpedal, wherein the computer is enabled to control the pulsed electrical power to have a power pulse of less than 20 milliseconds, and further wherein the computer is configured to increase the drive voltage in response to a load occurring at the tip of the needle and to decrease the drive voltage in response to the load being removed.