Dispersion compensation in a chirped pulse amplification system

• US 8,189,971 B1
• Filed: 03/19/2008
• Issued: 05/29/2012
• Est. Priority Date: 01/23/2006
• Status: Expired due to Fees

• Current Assignee: Rayd LLC
• Original Assignee: Raydiance, Inc. (Coherent Corp.)
• Inventors: Vaissie, Laurent, Brennan, III, James Francis
• Primary Examiner(s): ROJAS, OMAR R
• Application Number:
  US12/077,658
• Time in Patent Office: 1,532 Days
• Field of Search: None
• US Class Current: 385/37
• CPC Class Codes: G02B 6/2706 as bulk elements, i.e. free space arrangements external to a light guide, e.g. polarising beam splitters
• CPC Class Codes: G02B 6/2931 Diffractive element operating in reflection
• CPC Class Codes: G02B 6/2932 comprising a directional router, e.g. directional coupler, circulator
• CPC Class Codes: H01S 3/0057 Temporal shaping, e.g. pulse compression, frequency chirping soliton generation and propagation G02F1/3513, H01S3/063 and H01S3/108
• CPC Class Codes: H01S 3/0675 Resonators including a grating structure, e.g. distributed Bragg reflectors [DBR] or distributed feedback [DFB] fibre lasers
• CPC Class Codes: H01S 3/06754 Fibre amplifiers H01S3/06708 takes precedence
• CPC Class Codes: H01S 3/083 Ring lasers fibre ring lasers H01S3/06791
• CPC Class Codes: H01S 3/2308 Amplifier arrangements, e.g. MOPA
• CPC Class Codes: H01S 3/235 Regenerative amplifiers

Abstract

Systems and methods for producing ultra-short optical pulses are provided. According to various embodiments, optical pulses are generated, stretched, amplified, and compressed to ultra-short lengths. In order to achieve the ultra-short lengths, dispersion compensation is provided prior to amplification and optionally before compression. Dispersion compensation prior to amplification can be performed by passing the optical pulses through a polarization-maintaining fiber that includes a nonlinear Bragg grating. In some embodiments, the optical pulses are repeatedly circulated through the polarization-maintaining fiber that includes the nonlinear Bragg grating. Dispersion compensation before compression can be achieved by passing the amplified optical pulse through another length of polarization-maintaining fiber.

Claims

1. A method comprising:

generating an optical pulse;

stretching the optical pulse to produce a stretched optical pulse;

producing a dispersion-compensated optical pulse by passing the stretched optical pulse through a polarization-maintaining fiber including a nonlinear Bragg grating;

circulating the dispersion-compensated optical pulse through the polarization-maintaining fiber including the nonlinear Bragg grating;

producing an amplified optical pulse from the dispersion-compensated optical pulse; and

compressing the amplified optical pulse.

2. The method of claim 1 further comprising passing the amplified optical pulse through a length of polarization-maintaining fiber before compressing the amplified optical pulse.

3. A method comprising:

generating an optical pulse;

producing a dispersion-compensated optical pulse by passing the optical pulse through a polarization-maintaining fiber including a nonlinear Bragg grating;

circulating the dispersion-compensated optical pulse through the polarization-maintaining fiber including the nonlinear Bragg grating;

stretching the dispersion-compensated optical pulse to produce a stretched optical pulse;

producing an amplified optical pulse from the stretched optical pulse; and

compressing the amplified optical pulse.

4. The method of claim 3 further comprising passing the amplified optical pulse through a length of polarization-maintaining fiber before compressing the amplified optical pulse.

5. A method comprising:

generating an optical pulse;

producing a stretched and dispersion-compensated optical pulse by passing the optical pulse through a polarization-maintaining fiber including a nonlinear Bragg grating;

circulating the stretched and dispersion-compensated optical pulse through the polarization-maintaining fiber including the nonlinear Bragg grating;

producing an amplified optical pulse from the stretched and dispersion-compensated optical pulse; and

compressing the amplified optical pulse.

6. The method of claim 5 further comprising passing the amplified optical pulse through a length of polarization-maintaining fiber before compressing the amplified optical pulse.

7. The method of claim 5 further comprising directing the compressed amplified optical pulse toward a target as an ablation beam.

8. The method of claim 7 further comprising focusing the ablation beam through a variable-focus lens onto the target using a controller.

9. The method of claim 7 further comprising sensing a reflection from the target and controlling the ablation beam according to a color of the target area.