Granted Patent B2

US 7,143,769 · App. 10/916,367 · Granted Dec 5, 2006

Abstract

Claims (51)

1. A method of surgical material removal from a body by optical-ablation with controlled pulse energy, comprising the steps of:

utilizing an optical oscillator in the generation of a series of wavelength-swept-with-time pulses;

passing electrical current through at least one pump diode to generate pumping light;

optically pumping an optical amplifier using the pumping light;

amplifying the wavelength-swept-with-time pulses using the optical amplifier to produce amplified pulses;

measuring an energy of the amplified pulses;

controlling pump diode current in order to vary the pulse energy of amplified pulses;

time-compressing the amplified pulses using a compressor to produce time-compressed amplified pulses;

illuminating a portion of the body with the time-compressed amplified pulses; and

using more than one optical amplifiers in a mode in which amplified pulses from a first of the optical amplifiers are delayed such that they arrive one or more nanoseconds after amplified pulses from a second of the optical amplifiers, to enable control of ablation rate independent of pulse energy.

2. The method of claim 1 , wherein the optical oscillator, optical amplifier and compressor are within a man-portable system.

3. The method of claim 1 , wherein the compressor includes an air-path between gratings compressor.

4. The method of claim 1 , wherein the time-compressed amplified pulses have a sub-picosecond duration.

5. The method of claim 1 , wherein a member of the wavelength-swept-with-time pulses have a duration between 10 picoseconds and one nanosecond.

6. The method of claim 1 , wherein the ablation is from an outside surface of the body.

7. The method of claim 1 , wherein the ablation is done inside of the body.

8. The method of claim 1 , wherein the optical amplifier is a fiber amplifier.

9. The method of claim 1 , wherein the amplified pulses applied to the portion of the body have a pulse energy between 2.5 and 3.6 times an ablation threshold of the portion of the body.

10. The method of claim 1 , wherein the generation of a series of wavelength-swept-with-time pulses is at a fixed repetition rate.

11. A method of surgical material removal from a body by optical-ablation with controlled pulse energy, comprising the steps of:

utilizing an optical oscillator in the generation of a series of wavelength-swept-with-time pulses at a fixed repetition rate;

passing electrical current through or least one pump diode to generate pumping light;

optically pumping an optical amplifier using the pumping light;

amplifying the wavelength-swept-with-time pulses using the optical amplifier to produce amplified pulses;

measuring an energy of the amplified pulses;

controlling pump diode current in order to vary the pulse energy of amplified pulses;

time-compressing the amplified pulses using a compressor to produce time-compressed amplified pulses;

illuminating a portion of the body with the time-compressed amplified pulses; and

selecting pulses from the series of wavelength-swept-with-time pulses, pulse selection being configured to be controllably varied to give a selected pulse repetition rate that is a fraction of the fixed repetition rate as a first control of ablation rate and controlling pump diode current as a second control of ablation rate, whereby ablation rate is controllable independent of pulse energy.

12. A method of material removal by optical-ablation with controlled pulse energy, comprising the steps of:

utilizing an optical oscillator in the generation of a wavelength-swept-with-time pulse;

passing electrical current through at least one pump diode to generate pumping light;

optically pumping an optical amplifier, using the pumping light;

controlling pump diode current;

amplifying the wavelength-swept-with-time pulse using the optical amplifier to generate an amplified pulse;

time-compressing the amplified pulse to generate a time-compressed amplified pulse;

illuminating a portion of the body with the time-compressed amplified pulse, whereby controlling the pump diode current controls the pulse energy of the amplified pulse; and

delivering the amplified pulse to a target in a manner such that an ablation rate of the material is independent of the pulse energy of the amplified pulse.

13. The method of claim 12 , wherein a multi-position selector switch is used to select an optical-pumping-power level and the pump diode current is controlled to control optical-pumping power to that level.

14. The method of claim 12 , wherein a selector switch is used to select a pump diode current level and the pump diode current is controlled to that level.

15. The method of claim 12 , wherein the optical amplifier is a fiber amplifier.

16. The method of claim 12 , wherein an ablation rate is responsive to a first control comprising pulse selection and to a second control comprising varying the amplification of the wavelength-swept-with-time pulses by adjusting a pump diode current, whereby the ablation rate is controllable independent of pulse energy.

17. A system for material removal from a body by optical-ablation with controlled pulse energy, comprising:

an optical oscillator to generate a series of wavelength-swept-with-time pulses;

a pulse selector configured for selecting pulses from the series of wavelength-swept-with-time pulses for controlling ablation rate independent of the pulse energy;

an optical amplifier configured for amplifying the wavelength-swept-with-time pulses to produce amplified pulses;

a measurement feedback configured for measuring an energy of the amplified pulses and controlling the pulse selector; and

a compressor configured for time-compressing the amplified pulses.

18. The system of claim 17 , wherein the ablation rate is responsive to a first control comprising the pulse selector and to a second control comprising the optical amplifier wherein amplification of the wavelength-swept-with-time pulses is variable using a pump diode current, whereby ablation rate is controllable independent of pulse energy.

19. The system of claim 17 , wherein the measurement feedback is used to control the pump diode current.

20. The system of claim 17 , wherein the pulse selector selects a fraction of a total number of the wavelength-swept-with-time pulses, the fraction being responsive to the measurement feedback.

Assignments (7)