Coherent, Inc.

Andrei Starodoumov

Norman Hodgson

Dmitri Simanovski

Paul Crittenden

Andreas Diening

Skip Bettencourt

Sergei V Govorkov

R Russel Austin

Serguei Anikitchev

Murray Keith Reed

Arnaud Lepert

Ronald Lambert

Kevin Elton Lindsay

Michael Snadden

An apparatus for generating visible light including a laser source emitting a fundamental beam, an optically nonlinear crystal, and a seed source emitting a seed beam. The optically nonlinear crystal receives the fundamental beam. The fundamental beam propagates in the nonlinear crystal at a first phase-matching angle for second-harmonic generation. A portion of the fundamental beam is converted into a second-harmonic beam that propagates in the nonlinear crystal at the first phase-matching angle for optical parametric generation. The seed source emits a seed beam having a wavelength longer than the second-harmonic beam. The seed beam is directed into the nonlinear crystal and propagates at a second phase-matching angle for the optical parametric amplification. A portion of the second-harmonic beam is converted into a signal beam at the seed wavelength and an idler beam by the optical parametric amplification.

Single Crystal optical parametric amplifier

Laser-apparatus includes a fiber-MOPA arranged to deliver amplified seed optical pulses having a wavelength of about 1043 nanometers to a multi-pass ytterbium-doped yttrium aluminum garnet solid-state optical amplifier for further amplification.

High power sub-400 femtosecond MOPA with solid-state power amplifier

An apparatus for generating and amplifying laser beams at approximately 1 micrometer wavelength is disclosed. The apparatus includes an ytterbium-doped gain-crystal pumped by an ytterbium fiber-laser. The fiber-laser enables a pump wavelength to be selected that minimizes heating of the gain-crystal. The apparatus can be configured for generating and amplifying ultra-fast pulses, utilizing the gain-bandwidth of ytterbium-doped gain-crystals.

Fiber-laser pumped crystal-laser

A mode-locked fiber MOPA delivers pulses of laser-radiation. A super-continuum generator including a bulk spectral-broadening element and a negative group-delay dispersion (NGDD) device is arranged to receive a pulse from the MOPA and cause the pulse to make a predetermined number of sequential interactions with the broadening element and the NGDD device. After making the predetermined interactions, the pulse is delivered from the super-continuum generator with a very broad spectral-bandwidth and a very short duration.

Tunable femtosecond laser-pulse source including a super-continuum generator

Pulses from a mode-locked Yb-doped laser () are spectrally broadened in an optical fiber (), and temporally compressed in a grating compressor (), then frequency-doubled () and used to pump an optical parametric oscillator (OPO) (). The OPO output is tunable over a wavelength range from about 600 nm to about 1100 nm. Mode-locking in the Yb-doped laser () is accomplished with a SESAM () or by Kerr-lens mode-locking with a Kerr medium () and a hard aperture ().

Optical parametric oscillator pumped by femtosecond thin-disk laser

A mode-locked fiber laser has a resonator including a gain-fiber, a mode-locking element, and a spectrally-selective dispersion compensating device. The resonator can be a standing-wave resonator or a traveling-wave resonator. The dispersion compensating device includes only one diffraction grating combined with a lens and a mirror to provide a spatial spectral spread. The numerical aperture of the gain-fiber selects which portion of the spectral spread can oscillate in the resonator.

Short-pulse fiber-laser

An optical amplifier for use as a final amplification stage for a fiber-MOPA has a gain-element including a thin wafer or chip of ytterbium-doped YAG. An elongated gain-region is formed in gain-element by multiple incidences of radiation from a diode-laser bar.

High-gain face-pumped slab-amplifier

A fiber-MOPA includes a seed-pulse source followed by fiber amplifier stages. The seed pulse source delivers signal pulses for performing a laser operation and delivers radiation between the seed pulses to maintain the collective average of the seed pulse power and intermediate radiation power constant. Keeping this average power constant keeps the instantaneous available gain of the fiber amplifier stages constant. This provides that the seed pulse delivery can be changed from one regime to a next without a period of instability between the regimes.

Fiber-MOPA apparatus for delivering pulses on demand

A hybrid CW MOPA includes an OPS-laser resonator delivering radiation in a plurality of longitudinal lasing-modes or wavelengths. The multiple longitudinal mode output is amplified in a fiber-amplifier. Amplified lasing-modes from the fiber-amplifier are frequency-converted by an optically nonlinear crystal in a ring-resonator having the same length as the laser resonator, such that the ring-resonator is resonant for all of the amplified lasing-modes.

Externally frequency-converted CW hybrid MOPA

A mode-locked fiber laser has a resonator including a gain-fiber, a mode-locking element, and a spectrally-selective dispersion compensating device. The resonator can be a standing-wave resonator or a traveling-wave resonator. The dispersion compensating device includes only one diffraction grating combined with a lens and a minor to provide a spatial spectral spread. The numerical aperture of the gain-fiber selects which portion of the spectral spread can oscillate in the resonator.

In a frequency-tripled fiber-MOPA, a pre-amplified plane-polarized seed-pulse having a fundamental frequency is divided into two pulse-components, plane-polarized in polarization-orientations at 90-degrees to each other. The fundamental-wavelength pulse-components are amplified in a common amplifier-fiber. The amplified components are separately propagated on different optical paths. One of the amplified components is frequency-doubled. The frequency-doubled component on one path and fundamental-frequency component on the other path are then combined on a common-path and sum-frequency mixed to provide a frequency-tripled pulse.

Frequency-tripled fiber-MOPA

Pulses from a mode-locked Yb-doped laser are spectrally broadened, and temporally compressed, then frequency-doubled and used to pump an optical parametric oscillator (OPO). The OPO output is tunable over a wavelength range from about 600 nm to about 1100 nm.

Master oscillator power amplifier (MOPA) apparatus includes two seed-pulse sources coupled to a single fiber amplifier including one or more stages of amplification. One of the seed-pulse sources is a single-mode source generating pulses having a duration selectively variable between about 0.1 ns and 10 ns. The other seed-pulse source is a multi-mode source generating pulses having a duration selectively variable between about 1 ns and 10 &#x3bc;s. Selectively operating one or the other of the seed-pulse sources provides that the apparatus can deliver pulses selectively variable in a range between about 0.1 ns and 10 &#x3bc;s.

Pulsed fiber-MOPA with widely-variable pulse-duration

Fundamental-wavelength pulses from a fiber a laser are divided into three or more pulse portions and the three or more portions are separately amplified. Two or more of the amplified fundamental-wavelength pulse-portions are combined and frequency-doubled. The frequency doubled portion is sum-frequency mixed with one or more of the other amplified fundamental wavelength pulse-portions to provide third-harmonic radiation pulses.

Growing community of inventors

Cupertino, CA, United States of America

Andrei Starodoumov