Environmentally stable passively modelocked fiber laser pulse source

• US 5,689,519 A
• Filed: 12/20/1993
• Issued: 11/18/1997
• Est. Priority Date: 12/20/1993
• Status: Expired due to Term

• Current Assignee: IMRA America Incorporated (Aisin Corp.), Board of Regents of the University of Michigan (University of Michigan)
• Original Assignee: IMRA America Incorporated (Aisin Corp.), Board of Regents of the University of Michigan (University of Michigan)
• Inventors: Harter, Donald J., Fermann, Martin E.
• Primary Examiner(s): Bovernick, Rodney B.
• Assistant Examiner(s): Wise, Robert E.
• Application Number:
  US08/169,707
• Time in Patent Office: 1,429 Days
• Field of Search: 372/6, 372/18, 372/99, 372/105
• US Class Current: 372/18
• CPC Class Codes: H01S 3/067 Fibre lasers
• CPC Class Codes: H01S 3/08059 Constructional details of the reflector, e.g. shape mirrors in general G02B5/08; mountings for mirrors G02B7/18
• CPC Class Codes: H01S 3/1112 Passive mode locking
• CPC Class Codes: H01S 3/1115 using intracavity saturable absorbers
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

The present invention is directed to providing an environmentally stable, ultra-short pulse source. Exemplary embodiments relate to passively modelocked ultra-short fiber lasers which are insensitive to temperature variations and which possess only negligible sensitivity to pressure variations. Further, exemplary embodiments can be implemented in a cost-effective manner which render them commercially practical in unlimited applications. Arbitrary fiber lengths (e.g., on the order of 1 millimeter to 1 kilometer, or greater) can be used to provide an ultra-short pulse with a cost-effective architecture which is commercially practical.

Claims

1. A passively modelocked laser comprising:

means for generating laser energy, said laser energy generating means having a cavity which includes;

a gain medium for amplifying energy in the cavity;

means for reflecting energy along an axis which passes through the gain medium;

means for compensating linear phase drifts of the gain medium;

means for outputting laser energy generated within said cavity;

a doped highly-birefringent fiber; and

low-birefringent fiber operably connected with said highly-birefringent fiber for transmitting laser energy along said axis of the cavity.

2. A passively modelocked laser according to claim 1, wherein said gain medium includes highly-birefringent fiber.

3. A passively modelocked laser comprising:

means for generating laser energy, said laser energy generating means having a cavity which includes;

a gain medium for amplifying energy in the cavity;

means for reflecting energy along an axis which passes through the gain medium;

means for compensating linear phase drifts of the gain medium;

means for outputting laser energy generated within said cavity; and

a polarization beam splitter and a fiber isolator for output coupling of laser light from the cavity.

4. A passively modelocked laser comprising:

means for generating laser energy, said laser energy generating means having a cavity which includes;

a gain medium for amplifying energy in the cavity;

means for reflecting energy along an axis which passes through the gain medium;

means for compensating linear phase drifts of the gain medium;

means for outputting laser energy generated within said cavity; and

a fiber stretcher for initiating modelocking of the laser.

5. A passively modelocked laser comprising:

means for generating laser energy, said laser energy generating means having a cavity which further includes;

a low-birefringent fiber; and

a doped highly-birefringent fiber connected to said low-birefringent fiber along an axis through which laser energy is transmitted within the cavity.

6. A passively modelocked laser according to claim 5, wherein said laser energy generating means is a fiber laser for producing ultra-short pulses.