Method and apparatus for generating long output pulses from flashlamp-excited lasers

• US 5,287,380 A
• Filed: 02/19/1993
• Issued: 02/15/1994
• Est. Priority Date: 02/19/1993
• Status: Expired due to Term

• Current Assignee: Candela Corporation
• Original Assignee: Candela Laser Corporation
• Inventors: Hsia, James C.
• Primary Examiner(s): Epps, Georgia Y.
• Assistant Examiner(s): Wise, Robert E.
• Application Number:
  US08/020,118
• Time in Patent Office: 361 Days
• Field of Search: 372/38, 372/53, 372/69, 372/70, 606/2
• US Class Current: 372/69
• CPC Class Codes: A61B 18/20 using laser
• CPC Class Codes: A61B 18/203 applying laser energy to the outside of the body
• CPC Class Codes: A61B 2018/00452 Skin
• CPC Class Codes: H01S 3/092 of flash lamp H01S3/0937 takes precedence ; flash lamps per se H01J61/80; circuit arrangements for operating flash lamps in general H05B41/30
• CPC Class Codes: H01S 3/213 including an organic dye

Abstract

A flashlamp-excited laser for producing a pulsed beam of laser light of long duration (e.g., greater than 500 microseconds) comprises a flashlamp driven by a pulse forming circuit which generates a ramp pulse having an amplitude generally increasing with time during substantially the entire duration of the pulsed beam of laser light produced by the laser.

Claims

1. A method of generating a pulsed beam of laser light of long duration from a flashlamp-excited laser, comprising:

generating a ramp pulse having an amplitude which generally increases with time during substantially the entire duration of a pulsed beam of laser light produced by a flashlamp-excited laser, and

driving the flashlamp-excited laser with the ramp pulse.

2. The method of claim 1 wherein the duration of the pulsed beam of laser light is greater than 500 microseconds.

3. The method of claim 1 wherein the amplitude of the ramp pulse increases by a factor of about 2 or greater during substantially the entire duration of the pulsed beam of laser light.

4. The method of claim 1 wherein the pulsed beam of laser light has an energy level of about 0.5 Joules or greater.

5. The method of claim 1 wherein the flashlamp-excited laser is used to treat cutaneous vascular lesions.

6. The method of claim 1 wherein a lasing medium associated with the flashlamp-excited laser comprises a dye carried by a liquid.

7. A method of generating a pulsed beam of laser light of long duration, comprising:

providing a flashlamp-excited dye laser for producing a pulsed beam of laser light,

generating a ramp pulse having an amplitude which generally increases with time during substantially the entire duration of the pulsed beam of laser light, and

driving the flashlamp-excited laser with the ramp pulse.

8. A flashlamp-excited laser for producing a pulsed beam of laser light of long duration, comprising:

a flashlamp driven by a pulse forming circuit which generates a ramp pulse having an amplitude generally increasing with time during substantially the entire duration of a pulsed beam of laser light produced by the laser.

9. The flashlamp-excited laser of claim 8 wherein a lasing medium associated with the laser comprises a dye carried by a liquid.

10. The flashlamp-excited dye laser of claim 9 wherein the duration of the pulsed beam of laser light is greater than 500 microseconds.

11. The flashlamp-excited dye laser of claim 10 wherein the amplitude of the ramp pulse increases by a factor of about 2 or greater during substantially the entire duration of the pulsed beam of laser light.

12. The flashlamp-excited dye laser of claim 11 wherein the pulsed beam of laser light has an energy level of about 0.5 Joules or greater.

13. The flashlamp-excited dye laser of claim 12 wherein the laser is used to treat cutaneous vascular lesions.