An optical device with photon flipping for converting an incident light flux into a practically monochromatic light beam, the device including a cladding area including a photon crystal microstructure, the photon crystal microstructure having an allowed spectral band and a spectral band gap; a flipping area including a flipping fluorescent dye which has a spectral band for absorbing fluorescence, which covers at least part of the allowed spectral band, and a spectral band for emitting fluorescence, which covers at least part of the spectral band gap of the photon crystal microstructure; a central area arranged to enable propagation of a monochromatic light beam having a wavelength in the spectral band gap, the central area being surrounded by the photon crystal microstructure; the core area having a thickness which is less than or equal to five times the wavelength of the maximum fluorescence emission of the flipping fluorescent dye.

There is provided a photonic bandgap fiber used in a state in which at least a part of the photonic bandgap fiber is bent at radii of 15 cm or greater and 25 cm or less. A large number of high refractive index portions 57 are disposed in a nineteen-cell core type in three layers, and a V value is 1.5 or greater and 1.63 or less. In the high refractive index portions 57, conditions are defined that a relative refractive index difference is % and a lattice constant is m so as to remove light in a higher mode at the bent portion as described above.

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 includes a core extending along the length of said longitudinal axis and a cladding region surrounding the core. At least the cladding region includes 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 includes hydrogen and/or deuterium. In at least the degradation resistant length section the PCF further includes a main coating surrounding the cladding region, which main coating is hermetic for the hydrogen and/or deuterium at a temperature below T.sub.h, wherein T.sub.h is at least about 50 C., preferably 50 C.<T.sub.h<250 C.

Optical components and methods of manufacture thereof. A first optical component has a hollow-core photonic crystal fiber includes internal capillaries for guiding radiation and an outer capillary sheathing the internal capillaries; and at least an output end section having a larger inner cross-sectional dimension over at least a portion of the output end section than an inner cross-sectional dimension of the outer capillary along a central portion of the hollow-core photonic crystal fiber prior to the output end section. A second optical component includes a hollow-core photonic crystal fiber and a sleeve arrangement.

Method of laser modifying an optical fibre to form a modified region at a target location within the fibre, comprising positioning at least a portion of an optical fibre in a laser system for modification by a laser, applying a correction to an active optical element of the laser system to modify wavefront properties of the laser to counteract an effect of aberration on laser focus, and laser modifying the optical fibre at the target location using the laser with the corrected wavefront properties to produce the modified region.

Method of laser modifying an optical fibre to form a modified region at a target location within the fibre, comprising positioning at least a portion of an optical fibre in a laser system for modification by a laser, applying a correction to an active optical element of the laser system to modify wavefront properties of the laser to counteract an effect of aberration on laser focus, and laser modifying the optical fibre at the target location using the laser with the corrected wavefront properties to produce the modified region.

Optical components and methods of manufacture thereof. A first optical component has a hollow-core photonic crystal fiber includes internal capillaries for guiding radiation and an outer capillary sheathing the internal capillaries; and at least an output end section having a larger inner cross-sectional dimension over at least a portion of the output end section than an inner cross-sectional dimension of the outer capillary along a central portion of the hollow-core photonic crystal fiber prior to the output end section. A second optical component includes a hollow-core photonic crystal fiber and a sleeve arrangement.

A microstructured optical fiber including a core region and a cladding region which surrounds the core region. The cladding region includes a plurality of cladding features within a cladding background material, wherein the cladding region includes an inner cladding region with at least one inner ring of cladding features and an outer cladding region with at least three outer cladding rings of outer cladding features. The inner cladding features have a first characteristic diameter and the outer cladding region includes a plurality of outer cladding features having a characteristic diameter smaller than the first characteristic diameter. The first characteristic diameter is at least about 10% larger than an average diameter of the outer cladding features and the core region has a diameter of at least about 2 m. A cascade optical fiber with at least one fiber as described, as well as a source of optical supercontinuum generation.

An optical sensor that includes a photonic crystal fiber (PCF) and an optical coupler. The PCF includes a hollow core with a first diameter (Dc), an inner cladding section, and an outer layer surrounding the inner cladding section. The inner cladding section includes a cladding material and a plurality of spaced apart circular-shaped channels disposed in the cladding material surrounding the hollow core. The cladding material includes at least one of glass, ceramic, and glass-ceramic. Each spaced apart circular-shaped channel has substantially the same size and an average diameter (d). A first end of the PCF is in optical communication with a light source and a second end of the PCF is in optical communication with the optical coupler.

A quantum entanglement device and a method of manufacture thereof are described. Specifically, an optical fiber for generating entangled photons is described that includes an optical core and photon entanglement media disposed relative to the optical core. The photon entanglement media includes at least one non-linear crystal, such as Barium Borate. A method of manufacturing an optical fiber is also described that includes providing a fiber preform that contains a nonlinear optical crystal within it, heating the fiber preform until the fiber preform reaches a predetermined temperature, and drawing the optical fiber form the preform, thereby generating an optical fiber having a photon entanglement media disposed therein, where the photon entanglement media comprises at least one non-linear crystal.