OPTICAL FIBERS, SOURCES OF OPTICAL RADIATION AND METHODS FOR PROVIDING LOW-SPECKLE OPTICAL RADIATION

摘要

The present disclosure relates more particularly to active optical fibers, amplified spontaneous emission (ASE) sources using such active optical fibers, and imaging and detection systems and methods using such ASE sources. In one aspect, the disclosure provides an active optical fiber that includes a rare earth-doped gain core configured to emit radiation at at least a peak wavelength emitted wavelength when pumped with pump radiation having a pump wavelength; a pump core surrounding the gain core; and a cladding surrounding the pump core, wherein the value M=16R2(NA)2/λ2 in which R is the gain core radius, NA is the active optical fiber numerical aperture, and λ is the peak emitted wavelength, is at least 50, or at least 100. The present disclosure also provides an optical source that includes the optical fiber coupled to a pump source.

主权项

1. A source of optical radiation comprising
an active optical fiber having a first end and a second end, the active optical fiber comprising
a gain core, the gain core being configured to emit radiation at at least a peak wavelength emitted wavelength when pumped with pump radiation having a pump wavelength, the gain core being doped with a rare earth element, the gain core having a refractive index at the peak emitted wavelength;a pump core surrounding the gain core, the pump core having a refractive index at the peak emitted wavelength less than the refractive index of the gain core at the peak emitted wavelength, the pump core being configured to substantially confine radiation of the peak emitted wavelength within the gain core;a cladding surrounding the pump core, the cladding having a refractive index at the pump wavelength less than the refractive index of the pump core at the pump wavelength, the cladding being configured to substantially confine radiation of the pump wavelength within the pump core and the gain corewherein the value M=16R2(NA)2/λ2 in which R is the gain core radius, NA is the active optical fiber numerical aperture, and λ is the peak emitted wavelength, is at least 50, or at least 100; and one or more pump sources operatively coupled to the active optical fiber, the one or more pump sources being configured to pump the active optical fiber with radiation of the pump wavelength,wherein the source of optical radiation is configured to output radiation of at least the peak emitted wavelength from the second end of the active optical fiber.