Microchip-Yb fiber hybrid optical amplifier for micro-machining and marking

An optical fiber termination and mode matching system for increasing an optical damage threshold at fiber ends, comprising:

• an optical element bonded to ends of the fiber, and having a diameter at least as great as that of an inner cladding of the fiber;
• a beam being focused at a first location relative to said optical element and said fiber;
• such that a beam waist of said beam is reduced to a value approximating a beam waist of a fundamental mode in a core of said fiber, said fiber being multimode fiber;
• and
• said optical element permitting beam expansion at an exit end of said fiber.

A multimode amplifier, comprising;

• a multimode fiber having a core region and a cladding region;
• and input and output ends;
• and
• an optical element bonded to said input and output ends, and
• configured to increase an optical damage threshold of said multimode fiber.

A fiber amplifier, comprising;

• a fiber having at least a cladding region;
• and input and output ends;
• and
• an optical element bonded to said input and output ends, and
• configured to increase an optical damage threshold of said fiber.

A high power fiber amplifier, comprising;

• a fiber having at least a core region and a cladding region;
• and
• input and output ends;
• and
• a coreless rod bonded to said input and output ends, and having a diameter at least as large as that of said cladding region, and
• being configured to increase an optical damage threshold of said fiber.

A buffer pigtail, comprising;

• a light input end;
• a light output end coupled to a fiber amplifier in a manner as to eliminate or minimize any interface therebetween;
• said pigtail having a composition matching that of the fiber of
• said fiber amplifier, and functioning to increase an optical damage threshold of said fiber amplifier.

An optical fiber termination and mode matching system for increasing an optical damage threshold at one or both ends of a fiber amplifier, said amplifier containing at least one core and one cladding region with different diameters;

• said amplifier comprising:
• an optical element bonded to at least one end of the fiber, and having a diameter substantially larger than said core region of said fiber;
• a pump beam being input into said fiber amplifier at a first location;
• and
• a signal beam being input into said fiber amplifier at a second location.

A fiber amplifier comprising;

• at least one core region and one cladding region,
• said amplifier further containing at least one end face used for the extraction of optical energy from said fiber amplifier, said optical energy being contained in a beam of a certain diameter;
• the diameter of said extracted optical beam at said at least one fiber end face being larger than the diameter of said fiber core;
• said increase in diameter at said fiber end face functioning to increase an optical damage threshold of said fiber amplifier.