The invention relates to a microstructured optical fiber for generating supercontinuum light upon feeding of pump light. The light can be incoherent light. The microstructured optical fiber has a first section and a second section, where the first and second sections have one or more different features. The invention also relates to a supercontinuum source comprising a microstructured optical fiber according to the invention.

An optical fiber for guiding an optical signal, the optical fiber includes: a core region; a cladding region surrounding the core region, the cladding region including an inner cladding region and an outer cladding region, wherein a plurality of the plurality of inner cladding features are of a first type of feature, wherein a plurality of the plurality of inner cladding features are of a second type of feature including an air hole in direct contact with the background material having a refractive index, n.sub.b, and wherein the inner cladding features are arranged in a substantially hexagonal lattice and the six nearest neighbors surrounding a first type of feature are of the second type of feature, and wherein no first type of feature is surrounded by less than six nearest neighbors of the second type of feature.

A microstructured optical fiber for generating supercontinuum light. The optical fiber includes a core and a cladding region surrounding the core. The optical fiber includes a first fiber length section, a second fiber length section as well as an intermediate fiber length section between said first and second fiber length sections. The first fiber length section has a core with a first characteristic core diameter larger than about 7 ?m. The second fiber length section has a core with a second characteristic core diameter, smaller than said first characteristic core diameter. The intermediate length section of the optical fiber includes a core which is tapered from said first characteristic core diameter to the second characteristic core diameter over a tapered length. Also, a supercontinuum light source including an optical fiber and a pump light source.

The invention concerns a Photonic Crystal Fiber (PCF) a method of its production and a supercontinuum light source comprising such PCF. The PCF has a longitudinal axis and comprises a core extending along the length of said longitudinal axis and a cladding region surrounding the core. At least the cladding region comprises a plurality of microstructures in the form of inclusions extending along the longitudinal axis of the PCF in at least a microstructured length section. In at least a degradation resistant length section of the microstructured length section the PCF comprises hydrogen and/or deuterium. In at least the degradation resistant length section the PCF further comprises a main coating surrounding the cladding region, which main coating is hermetic for the hydrogen and/or deuterium at a temperature below Th, wherein Th is at least about 50? C., preferably 50? C.<Th<250? C.

The invention relates to a supercontinuum light source comprising a microstructured optical fiber and a pump light source. The microstructured optical fiber comprises a core and a cladding region surrounding the core, as well as a first fiber length section, a second fiber length section and an intermediate fiber length section between said first and second fiber length sections. The first fiber length section comprises a core with a first characteristic core diameter. The second fiber length section comprises a core with a second characteristic core diameter, smaller than said first characteristic core diameter, where said second characteristic core diameter is substantially constant along said second fiber length section. The intermediate length section of the optical fiber comprises a core which is tapered from said first characteristic core diameter to said second characteristic core diameter over a tapered length.

A photonic displacement sensor comprises a photonic fiber including a) a core section having a first band gap aligned along an extended longitudinal axis, and b) a cladding section surrounding the core section having a second band gap. The first band gap is adapted to block a spectral band of radiation centered on a first wavelength that is directed along the longitudinal axis, and the second band gap is adapted to block a spectral band of radiation centered on a second wavelength that is directed transversely to the longitudinal axis, and wherein displacement is detected based on a shift in at least one of the first and second band gap of the photonic fiber, enabling an intensity of radiation to be detected that is in proportion to the displacement in the photonic fiber.

An optical fiber that is a photonic crystal fiber in which a plurality of holes is arranged along a longitudinal direction of the optical fiber, having a predetermined bending radius R determined according to a transmission distance L of the optical fiber and optical power output from the optical fiber, and having an inter-hole distance and a ratio d/ between a hole diameter d and the inter-hole distance such that light of a predetermined number of modes is transmitted and a bending loss of the light of a fundamental mode with the predetermined bending radius R is equal to or smaller than a predetermined value.

In an approach to measuring a magnetic field of a sample, a system includes an optical fiber comprising a first end and a second end, the optical fiber having a core; and a nitrogen vacancy (NV) diamond sensor; where the first end of the optical fiber is configured to receive excitation light from an optical excitation source; and the NV diamond sensor is coupled to the second end of the optical fiber with an optical matching material, the optical matching material configured to optically match the NV diamond sensor to the core of the optical fiber.

An illuming device for use in medically illuminating tissue of interest within a patient generally includes a light diffusing optical fiber and an at least partially optically opaque sheath that is mounted over the fiber for selective, sliding movement along the length thereof. By sliding the sheath relative to the optical fiber after it has been inserted into a patient to illuminate a particular area of tissue, the length, size, and/or shape of the light that is exposed to the tissue can be selectively controlled. Such in situ variation of the properties of the exposed light permit use of a single instrument and a single procedure regardless of variation in the size and shape of the diseased tissue being medically treated.

An optical fiber design method according to the present invention is a design method of a photonic crystal fiber having a plurality of holes arranged in the optical fiber along a longitudinal direction, in which a required effective cross-sectional area is calculated from a light wavelength, a transmission distance, and output power such that, in a cross section, a hole ratio which is an area of the holes per unit area is larger in a central side than in an outer side in a portion corresponding to a cladding, and a fiber structure (hole diameter and hole interval) corresponding to the effective cross-sectional area is calculated.