Step-index profile

About: Step-index profile is a research topic. Over the lifetime, 3104 publications have been published within this topic receiving 53199 citations.

Refractive index variable element and method of varying refractive index

Abstract: A refractive index variable element includes a structure including quantum dots having discrete energy levels and a dielectric matrix surrounding the quantum dots, and an electron injector injecting an electron into the quantum dots through the dielectric matrix.

Refractive index distribution measuring method and refractive index distribution measuring apparatus

Abstract: A method includes the steps of measuring a first transmitted wavefront in a first medium having a first refractive index and a second transmitted wavefront in a second medium having a second refractive index different from the first refractive index, and obtaining a refractive index distribution projected value of the object in each orientation by removing a shape component of the object utilizing measurement results of the first transmitted wavefront and the second transmitted wavefront and each transmitted wavefront of a reference object that has the same shape as that of the object and a specific refractive index distribution and is located in one of the first medium and the second medium with the same orientation as that of the object, and calculating a three-dimensional refractive index distribution of the object based on a plurality of refractive index distribution projected values corresponding to the plurality of orientations.

Simultaneous measurement of refractive index and temperature by integrating an external Fabry-Perot cavity with a fiber Bragg grating

Abstract: A fiber sensor for simultaneous measurements of refractive index and temperature based on the integration of a fiber Bragg grating (FBG) with an external Fabry-Perot (F-P) cavity is presented. The fringe contrast of the interference spectrum generated by the F-P cavity is used to determine the external refractive index, while the wavelength shift of the FBG is used to measure temperature. The result showed that the refractive index and temperature sensitivity for the integrated sensor is 8.1 × 10(-6) and 0.01006 nm/°C, respectively.

Photonic bandgap fibre, and use thereof

Abstract: An object of the present invention is to provide new designs of microstructured optical fibres that may be fabricated without use of voids, such as fibres being realized using silica and silica doping techniques. The invention relates to a microstructured optical fibre that guides light in a core region (52), where the fibre has a cladding region that comprises a background material (51) and a number of cladding features or elements (50) that are elongated in the longitudinal direction of the fibre and have a higher refractive index than the cladding background material. The core region has a lower effective refractive index than the cladding, and the fibre may guide light in the core by photonic bandgap effects. The present invention provides designs of photonic bandgap fibres that may operate without the use of voids in the cladding, thereby simplifying fabrication of photonic bandgap fibres compared to prior art. The invention further provides photonic bandgap fibers with tuneable waveguiding properties, such as tuneable polarization. The invention further relates to a number of specific fibre designs that provide improvements with respect to dispersion characteristics, mode field diameters, propagation losses, polarization mode dispersion and other issues of relevance to optical communication systems.