Supercontinuum light source

Patent metadata

Field	Value
Publication number	US-11154189-B2
Application number	US-201916581912-A
Country	US
Kind code	B2
Filing date	Sep 25, 2019
Priority date	Jun 1, 2012
Publication date	Oct 26, 2021
Grant date	Oct 26, 2021

Abstract

A supercontinuum light source can include a seed laser arranged to provide seed pulses with a pulse frequency F seed ; a pulse frequency multiplier (PFM) arranged to multiply the seed pulses by converting pulses having the pulse frequency F seed to pump pulses with a pulse frequency F pump , where F pump is larger than F seed ; and a non-linear element arranged to receive said pump pulses and convert said pump pulses to pulses of supercontinuum light. The PFM can further include a splitter for splitting pulses into first and second sub beams each having the same pulse frequency, where the PFM is configured such that the sub beams experience different delays; and a combiner for combining said first and second sub beams into a beam having the pulse frequency that is greater than said same pulse frequency. The splitter can have an uneven splitter ratio.

First claim

The invention claimed is:

1. A supercontinuum light source comprising:
a seed laser configured to provide seed pulses with a pulse frequency F seed ;
a pulse frequency multiplier (PFM) configured to multiply the seed pulses by converting seed pulses having the pulse frequency F seed to pump pulses with a pulse frequency F pump , where F pump is larger than F seed ;
a non-linear element configured to receive said pump pulses and convert said pump pulses to pulses of supercontinuum light; and
first and second amplifiers, one of the amplifiers configured to amplify pulses having the pulse frequency F seed and the other of the amplifiers configured to amplify pulses having the pulse frequency F pump ,
wherein said PFM is located between the amplifiers.

2. The supercontinuum light source of claim 1 , wherein said PFM comprises an attenuator configured to attenuate pulses of light having a pulse frequency that is less than F pump .

3. The supercontinuum light source of claim 1 , wherein said non-linear element comprises a microstructured optical fiber.

4. The supercontinuum light source of claim 1 , wherein F pump is 150 MHz or more.

5. The supercontinuum light source of claim 1 , wherein said seed laser is configured to provide seed pulses with a pulse duration t seed that is longer than about 1 ps.

6. The supercontinuum light source of claim 5 , wherein t seed is shorter than about 50 ps.

7. The supercontinuum light source of claim 1 , wherein the supercontinuum light source is configured such that the total average optical power in the range 400 nm-850 nm is less than 100 mW.

8. The supercontinuum light source of claim 1 , wherein the amplifiers provide an increase in pulse energy and peak power relative to an output from the seed laser.

9. The supercontinuum light source of claim 1 , wherein the supercontinuum light source is configured such that peak power of the pulses out of the first amplifier is constant.

10. The supercontinuum light source of claim 1 , wherein the supercontinuum light source is configured such that peak power of the pulses out of the second amplifier is constant.

11. The supercontinuum light source of claim 1 , wherein said seed laser comprises a mode locked Yb laser.

12. The supercontinuum light source of claim 11 , wherein said mode locked Yb laser comprises a fiber laser that is passively mode locked via a SESAM (Semiconductor Saturable Absorber Mirror).

Assignees

• Nkt Photonics As

Inventors

• Thomsen Carsten L
• Andersen Thomas Vestergaard
• Feuchter Thomas

Classifications

• G02F1/35 Primary

  Non-linear optics · CPC title

• G02F1/365

  in an optical waveguide structure (G02F1/377, {G02F1/395} take precedence) · CPC title

• G02B27/0927

  Systems for changing the beam intensity distribution, e.g. Gaussian to top-hat · CPC title

• G02F1/3528

  for producing a supercontinuum · CPC title

• A61B3/0008 Primary

  provided with illuminating means (A61B3/117, A61B3/14 take precedence) · CPC title