Abstract: An optical fibre that use index-guidance formed with a low index cladding or a microstructured cladding using voids/holes or low index features (404) together with multiple high index resonant cladding features (1205, 1206). One to three resonant cross sectional extending structure act as a filter by resonantly coupling light out to part of the cladding (1202) or other structures (fx. a high index outer cladding ring) that acts as light sink(s) at one to three wavelength when using one to three materials or features with different size, shape, refractive index profile or normalized frequency parameter. The fibre can be asymmetrical. The fibre can be adapted for suppression of higher order modes (HOM) and/or guiding light in a narrow spectral wavelength range and act as a band pass filter.

Abstract: The present invention relates to an optical fiber comprising at least a first end with an first end facet, the optical fiber comprising a core region capable of guiding light at a first wavelength ?; and a microstructured cladding region surrounding said core region. The cladding region comprises an inner cladding region and an outer cladding region. The inner cladding region comprises inner cladding features arranged in an inner cladding background material having a refractive index n1, said inner cladding features comprising thermally collapsible holes or voids. The outer cladding region comprising outer cladding features arranged in an outer cladding background material, said outer cladding features comprising solid material with refractive index n2, wherein n2 is lower than n1. The invention further relates to methods for splicing such an optical fiber to an optical component and to methods for using such an optical fiber.

Abstract: A method of manufacturing a microstructured fiber, includes: providing a preform having a plurality of elongate holes; mating at least one, but not all, of the holes with a connector to connect the hole(s) to an external pressure-controller; drawing the preform into the fiber while controlling gas pressure in the hole(s) connected to the pressure-controller.

Abstract: The disclosure relates to an optical fiber including a core and a cladding having a core material and a cladding material, respectively, wherein the fiber is a non-linear microstructured optical fiber, the microstructured optical fiber being obtainable by a method including loading the core material and optionally the cladding material with hydrogen and/or deuterium whereby the lifetime of the fiber may be extended in high pulse applications.

Abstract: A new deep blue extended super continuum light source is provided wherein said super continuum at least extends to a low wavelength border ?low low below 480 nm comprising a pump source which operates at a at least one wavelength ?pump and produces pump pulses of a duration (full width half maximum) longer than 0.1 picoseconds with a repetition rate higher than 1 MHz, and a peak power ?peak, and a micro-structured optical transmission medium having at least one wavelength of zero dispersion ?zero, and for the parameters for said pump source exhibiting a second order dispersion parameter ?2, and a non-linear parameter ? arranged so that the optical transmission medium exhibits a modulation instability gain extending to wavelengths above a wavelength ?high?1300 nm and a phase match between ?1ow and a wavelength ?match??high, wherein the pump is adapted to provide energy within the region of anomalous dispersion of the transmission medium.

Abstract: In a blue extended super continuum light source, when pulses of partly coherent monochromatic “pump” radiation of essentially constant amplitude are propagating through a microstructure fiber medium within a region of anomalous dispersion of the medium, then, provided the medium has a finite nonlinear coefficient of the index of refraction, the pump pulse is subject to a modulation instability. This results in formation of a train of narrow pulses with Tera Hertz repetition rate. Phase match between red shifted Raman solitons generated by the pump pulse and energy shed by the pump pulse at all frequencies with a group velocity below the pump pulse group velocity may lead to the formation of Cherenkov radiation. The solitons may seed Cherenkov radiation at different wavelengths depending on the actual fiber parameters. This allows extension of generated super continuum light beyond the four wave mixing limit when applying picosecond or nanosecond pump pulses.

Abstract: The invention relates to optical fibers for use in optical amplification of light, such as in optical fiber amplifiers and lasers and for use in delivery of high power light, in particular to a scheme for reducing amplified spontaneous emission at undesired wavelengths. The invention further relates to articles, methods and use. An object of the invention is achieved by a micro-structured optical fiber, which is adapted to guide light by the photonic bandgap effect and to have one or more pass bands and at least one stop-band over a wavelength range from ?stop1 to ?stop2. In an aspect of the invention, the at least one stop-band provides filter functions that suppress nonlinear effects.

Abstract: A method of generating supercontinuum optical radiation, the method comprising: (a) providing an optical waveguide (22), said optical waveguide exhibiting a dispersion characteristic of guided optical radiation, said dispersion characteristic comprising: (i) a first dispersion parameter (?21) at a first wavelength (?1), (ii) a second dispersion parameter (?22) at a second shorter wavelengths (?2), and (iii) a zero-dispersion parameter at a wavelength in between said first and said second shorter wavelengths; said optical waveguide further comprising at least one entrance for receiving optical radiation, and at least one exit for emitting guided optical radiation; (b) applying at least two laser radiation of said first (25) wavelength, (?1) at a first power (P1) and applying laser radiation of said second (26) shorter wavelength (?2) at a second power (P2) into said optical waveguide, said laser radiations at least partially overlapping between said at least one entrance and said at least one exit of said opti

Abstract: A new blue extended super continuum light source is claimed. When pulses of partly coherent monochromatic “pump” radiation of essentially constant amplitude is propagating through a microstructure fibre medium within a region of anomalous dispersion of the medium, then, provided the medium has a finite nonlinear coefficient of the index of refraction, the pump pulse is subject to a modulation instability. This instability results in the generation and exponential growth of sidebands, the two closest to the “pump” frequency being the dominant ones. The modulation frequency is proportional to the square root of the power in the carrier wave. In the time domain this leads to that the interaction between the medium and the radiation results in contraction of the width of the amplitude peaks, which results in formation of a train of narrow pulses with Tera Hertz repetition rate.

Abstract: The invention relates to an optical system arranged to provide an output which, in operation, comprises at least one figure of merit, Q. The system comprises an optical component having multiple working areas, said component being mounted on a support member. The system further comprises an optical beam path arranged to bring light into interaction with at least one working area of the optical component wherein the position of said working area(s) may be selected by relative movement between said path and said component while keeping Q substantially unaffected by said movement.

Abstract: An optical component including an acceptance fiber, e.g. a photonic crystal fiber, for propagation of pump and signal light, a number of pump delivery fibers and a reflector element that reflects pump light from the pump delivery fibers into the acceptance fiber. An optical component includes a) a first fiber having a pump core with an NA1, and a first fiber end; b) a number of second fibers surrounding the pump core of the first fiber, at least one of the second fibers has a pump core with an NA2 that is smaller than NA1, the number of second fibers each having a second fiber end; and c) a reflector element having an end-facet with a predetermined profile for reflecting light from at least one of the second fiber ends into the pump core of the first fiber.

Abstract: The present invention deals with optical systems for providing short laser pulses. An object of the invention is to provide an optical system providing compact and cost-effective short laser-pulses using fibers with anomalous dispersion and high non-linear thresholds. The object is achieved by a short pulse optical system for generating or processing short laser-pulses, said optical system comprises an optical fiber in the form of a photonic crystal fiber arranged to provide guidance of light in the core region due to the photonic bandgap effect (PBG), where light propagates in a hollow or solid core surrounded by a Silica cladding comprising a substantially periodic distribution of micro-structural elements, and where the refractive index of the core is lower than the effective refractive index of the cladding. The invention may be useful in applications such as laser-based micromachining, thin-film formation, laser cleaning, in medicine and biology.

Abstract: The invention relates to an article comprising a length of an optical fiber and a package, the optical fiber comprising a fiber Bragg grating dispersed over a FBG-section of the length of the optical fiber, the package comprising a carrier with a carrier surface for supporting at least a supported part of the optical fiber including the FBG-section. The invention further relates to an apparatus comprising the article, to its use and to a method of manufacturing such an article. The object of the present invention is to seek to provide an optimized (e.g. elongate) package having a relatively low sensitivity to mechanical vibrations from the environment. This is achieved by providing that the carrier surface for supporting the optical fiber comprising a fiber Bragg grating is convex in a longitudinal direction of the optical fiber during use of the article.

Abstract: A birefringent elongate waveguide for guiding light, comprises: a core region (110), comprising an elongate region of relatively low refractive index; and a cladding region (100), comprising elongate regions (105) of relatively low refractive index interspersed with elongate regions (117,120) of relatively high refractive index. In a transverse cross-section of the waveguide, a (5) relatively high refractive index boundary region (115) is provided that surrounds the core region and has either (1) at most two-fold rotational symmetry or (2) a rotational symmetry that reduces the rotational symmetry of the waveguide to at most two-fold rotational symmetry. The symmetry of the boundary region (115) results at least in part from azimuthal variations therein, which are substantially uncharacteristic of the cladding region (100).

Abstract: In a blue extended super continuum light source, when pulses of partly coherent monochromatic “pump” radiation of essentially constant amplitude are propagating through a microstructure fiber medium within a region of anomalous dispersion of the medium, then, provided the medium has a finite nonlinear coefficient of the index of refraction, the pump pulse is subject to a modulation instability. This results in formation of a train of narrow pulses with Tera Hertz repetition rate. Phase match between red shifted Raman solitons generated by the pump pulse and energy shed by the pump pulse at all frequencies with a group velocity below the pump pulse group velocity may lead to the formation of Cherenkov radiation. The solitons may seed Cherenkov radiation at different wavelengths depending on the actual fiber parameters. This allows extension of generated super continuum light beyond the four wave mixing limit when applying picosecond or nanosecond pump pulses.

Abstract: Refractive index modifications such as e.g. Fiber Bragg gratings in micro-structured Fiber are according to an aspect of the invention fabricated by first filling and/or purging the holes of the micro-structured fiber with inert gas or by evacuation and, optionally subsequently scaling the ends. Alternatively, the ends of the micro-structured fiber may be sealed without a preceding purging or evacuation of the holes. In this way hydrogen or deuterium present in the holes after photosensitizing loading will not react with atmospheric oxygen to form water. Water formed this way would otherwise seriously impair the grating formation process. Bragg gratings and other refractive index structures can thus be fabricated with high quality and predictable specifications in micro-structured fiber. Sealing the fiber ends also prevents in-diffusion of moisture. The invention may e.g. find application in connection with fiber optical sensors, high-power fiber lasers, etc.

Abstract: The light includes a laser (4), which operates at or near its fundamental wavelength and produces pulses of a duration longer than 0.5 ns, and a micro-structured optical fibre (9) arranged to guide the pulses, wherein the light is generated by the pulses in the fibre (9). The light source may e.g. be useful in applications such as spectral testing of fibre components and spectral analysis of chemical and biological samples.