Abstract:
An optical fiber for converting a Gaussian laser beam into a Bessel laser beam may include a first segment optically coupled to a second segment with a transition region, the first segment having a first outer diameter greater than a second outer diameter of the second segment. The first segment may include a first core portion with a first cladding portion extending around the first core portion. The second segment may include a second core portion with a second cladding portion extending around the second core portion. The optical fiber may have a non-axisymmetric refractive index profile or may be coupled to an end cap with a non-axisymmetric refractive index profile.
Abstract:
A light-diffusing optical fiber having nanostructured inner and outer core regions is disclosed. The nanostructured inner core region (30) is defined by a first configuration of voids (34) that defines a first amount of light scattering. The outer core region (50) is defined by a second configuration of voids (54) that defines a second amount of light scattering that is different from the first amount of light scattering. A cladding (100) surrounds the nanostructured core. Light scattered out of the inner core region scatters from the outer core region and then out of the cladding as scattered light. Selective bending of the light-diffusing optical fiber is used to define a bending configuration that allows for tailoring the intensity distribution of the scattered light emitted from the fiber as a function of the length of the fiber.
Abstract:
A system and method are provided for coupling a plurality of optical signals, such as data signals, between a corresponding plurality of single mode optical fibers (SMFs) and a multi-mode optical fiber (MMF), by optically coupling the optical signals of the SMFs with respective spaced-apart regions at a facet of the MMF, such that at least some of the regions partially overlap with a plurality of different spatial modes supported by the MMF. The optical coupling is performed by utilizing imaging and beam shaping optics configured to couple each of the SMF optical signals and the respective region at the MMF's optical pupil by carrying out the following: (i) imaging the SMF optical signal propagating in between the associated SMF and the respective region of the MMF to focus the optical signal emanating from the SMF onto the respective region or vice versa; and (ii) shaping the optical signal being focused to convert a lateral field distribution thereof, between a first predetermined field distribution corresponding to the SMF's spatial mode and a second predetermined field distribution at the respective region.
Abstract:
A sensing optical fiber comprising: a few-moded multi-segment core, said core comprising one core segment surrounded by another core segment, and at least one cladding surrounding said core; said core having an F factor (μm 2 ) of 100 μm 2 to 350 μm 2 , and is constructed to provide (i) an overlap integral between the fundamental optical guided mode and the fundamental acoustic guided mode of greater than 0.7 and (ii) the overlap integral between the LP11 optical guided mode and the fundamental acoustic guided mode at least 0.45.
Abstract:
An embodiment of an apparatus includes an optical fiber for which a complete orthogonal basis of propagating modes at an optical telecommunication frequency includes ones of the propagating modes with different angular momenta. The optical fiber has a tubular optical core and an outer optical cladding in contact with and surrounding the tubular optical core. The tubular optical core has a larger refractive index than the optical cladding. The tubular optical core is configured such that those of the propagating modes whose angular momenta have the lowest magnitude for the propagating modes have substantially the same radial intensity profile.
Abstract:
A few-mode optical fiber comprises a core surrounded by a cladding, having a step index profile that is structured to support propagation of a plurality of desired signal-carrying modes, while suppressing undesired modes. The core and cladding are configured such that the undesired modes have respective effective indices that are close to. or less than, the cladding index such that the undesired modes are leaky modes. The index spacing between the desired mode having the lowest effective index and the leaky mode with the highest effective index is sufficiently large so as to substantially prevent coupling therebetween.