Imra America, Inc.

University of Michigan

Other

Alliedsignal Inc.

Irma America, Inc.

Aisin Seiki Company, Ltd.

Donald J Harter

Martin E Fermann

Almantas Galvanauskas

Gregg D Sucha

Ingmar Hartl

Gyu Cheon Cho

Zhenlin Liu

Mark P Bendett

Lawrence Shah

Xinhua Gu

Salvatore F Nati

Liang Dong

Min Jiang

Rajesh S Patel

Gennady Imeshev

Alan Y Arai

Tadashi Yamamoto

Otho E Ulrich, Jr

William S Wong

James Bovatsek

Anand Hariharan

Ferenc Raksi

Yuzuru Uehara

Gyu Choen Cho

Ka K Wong

Wayne A Gillis

Mark Alan Arbore

Martin M Fejer

Michelle L Stock

Gerard A Mourou

Jeffrey A Squier

Jeff A Squier

John S Coe

Xinhu Gu

Jeff Squier

The invention describes classes of robust fiber laser systems usable as pulse sources for Nd: or Yb: based regenerative amplifiers intended for industrial settings. The invention modifies adapts and incorporates several recent advances in FCPA systems to use as the input source for this new class of regenerative amplifier.

Yb: and Nd: mode locked oscillators and fiber systems incorporated in solid-state short pulse laser systems

Holey fibers provide optical propagation. In various embodiments, a large core holey fiber comprises a cladding region formed by large holes arranged in few layers. The number of layers or rows of holes about the large core can be used to coarse tune the leakage losses of the fundamental and higher modes of a signal, thereby allowing the non-fundamental modes to be substantially eliminated by leakage over a given length of fiber. Fine tuning of leakage losses can be performed by adjusting the hole dimension and/or spacing to yield a desired operation with a desired leakage loss of the fundamental mode. Resulting holey fibers have a large hole dimension and spacing, and thus a large core, when compared to traditional fibers and conventional fibers that propagate a single mode. Other loss mechanisms, such as bend loss and modal spacing can be utilized for selected modes of operation of holey fibers.

Large core holey fibers

System for converting relatively long pulses from rep-rate variable ultrafast optical sources to shorter, high-energy pulses suitable for sources in high-energy ultrafast lasers. Fibers with positive group velocity dispersion (GVD) and self phase modulation are advantageously employed with the optical sources. These systems take advantage of the need for higher pulse energies at lower repetition rates so that such sources can be cost effective.

Inexpensive variable rep-rate source for high-energy, ultrafast lasers

A femtosecond laser based laser processing system having a femtosecond laser, frequency conversion optics, beam manipulation optics, target motion control, processing chamber, diagnostic systems and system control modules. The femtosecond laser based laser processing system allows for the utilization of the unique heat control in micromachining, and the system has greater output beam stability, continuously variable repetition rate and unique temporal beam shaping capabilities.

Femtosecond laser processing system with process parameters controls and feedback

An electronic circuit for controlling a laser system consisting of a pulse source and high power fiber amplifier is disclosed. The circuit is used to control the gain of the high power fiber amplifier system so that the amplified output pulses have predetermined pulse energy as the pulse width and repetition rate of the oscillator are varied. This includes keeping the pulse energy constant when the pulse train is turned on. The circuitry is also used to control the temperature of the high power fiber amplifier pump diode such that the wavelength of the pump diode is held at the optimum absorption wavelength of the fiber amplifier as the diode current is varied. The circuitry also provides a means of protecting the high power fiber amplifier from damage due to a loss of signal from the pulse source or from a pulse-source signal of insufficient injection energy.

Method and apparatus for controlling and protecting pulsed high power fiber amplifier systems

A laser utilizes a cavity design which allows the stable generation of high peak power pulses from mode-locked multi-mode fiber lasers, greatly extending the peak power limits of conventional mode-locked single-mode fiber lasers. Mode-locking may be induced by insertion of a saturable absorber into the cavity and by inserting one or more mode-filters to ensure the oscillation of the fundamental mode in the multi-mode fiber. The probability of damage of the absorber may be minimized by the insertion of an additional semiconductor optical power limiter into the cavity.

Multi-mode fiber amplifier

Yb: and Nd: mode-locked oscillators and fiber systems incorporated in solid-state short pulse laser systems

By compensating polarization mode-dispersion as well chromatic dispersion in photonic crystal fiber pulse compressors, high pulse energies can be obtained from all-fiber chirped pulse amplification systems. By inducing third-order dispersion in fiber amplifiers via self-phase modulation, the third-order chromatic dispersion from bulk grating pulse compressors can be compensated and the pulse quality of hybrid fiber/bulk chirped pulse amplification systems can be improved. Finally, by amplifying positively chirped pulses in negative dispersion fiber amplifiers, a low noise wavelength tunable seed source via anti-Stokes frequency shifting can be obtained.

All-fiber chirped pulse amplification systems

A modular ultrafast pulse laser system is constructed of individually pre-tested components manufactured as modules. The individual modules include an oscillator, pre-amplifier and power amplifier stages, a non-linear amplifier, and a stretcher and compressor. The individual modules can typically be connected by means of simple fiber splices.

Modular fiber-based chirped pulse amplification system

YB: and ND: mode-locked oscilltors and fiber systems incorporated in solid-state short pulse laser systems

Growing community of inventors

Ann Arbor, MI, United States of America

Donald J Harter