Low-dispersion optical fiber highly transparent in the UV spectral range

2004 ◽  
Vol 43 (12) ◽  
pp. 2896 ◽  
Author(s):  
Galina M. Ermolaeva
Keyword(s):  
Optical Fiber ◽  
Spectral Range ◽  
Low Dispersion

scholarly journals Vortex Polymer Optical Fiber with 64 Stable OAM States

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2776
Author(s):  
José A. Borda-Hernández ◽  
Claudia M. Serpa-Imbett ◽  
Hugo E. Hernandez Figueroa
Keyword(s):  
Optical Fiber ◽  
Optical Fibers ◽  
Communication Systems ◽  
Low Cost ◽  
Higher Order ◽  
Coupling Coefficients ◽  
Polymer Optical Fiber ◽  
Optical Polymer ◽  
Polymer Optical Fibers ◽  
Low Dispersion

This research introduces a numerical design of an air-core vortex polymer optical fiber in cyclic transparent optical polymer (CYTOP) that propagates 32 orbital angular momentum (OAM) modes, i.e., it may support up to 64 stable OAM-states considering left- and right-handed circular polarizations. This fiber seeks to be an alternative to increase the capacity of short-range optical communication systems multiplexed by modes, in agreement with the high demand of low-cost, insensitive-to-bending and easy-to-handle fibers similar to others optical fibers fabricated in polymers. This novel fiber possesses unique characteristics: a diameter of 50 µm that would allow a high mechanical compatibility with commercially available polymer optical fibers, a difference of effective index between neighbor OAM modes of around 10−4 over a bandwidth from 1 to 1.6 µm, propagation losses of approximately 15 × 10−3 dB/m for all OAM modes, and a very low dispersion for OAM higher order modes (±l = 16) of up to +2.5 ps/km-nm compared with OAM lower order modes at a telecom wavelength of 1.3 µm, in which the CYTOP exhibits a minimal attenuation. The spectra of mutual coupling coefficients between modes are computed considering small bends of up to 3 cm of radius and slight ellipticity in the ring of up to 5%. Results show lower-charge weights for higher order OAM modes.

scholarly journals Miniaturized Interferometric Sensors with Spectral Tunability for Optical Fiber Technology—A Comparison of Size Requirements, Performance, and New Concepts

Photonics ◽  
2021 ◽  
Vol 8 (8) ◽  
pp. 332
Author(s):  
Hartmut Hillmer ◽  
Carsten Woidt ◽  
Aliaksei Kobylinskiy ◽  
Matthias Kraus ◽  
André Istock ◽  
...  
Keyword(s):  
Optical Fiber ◽  
Spectral Range ◽  
Optical Sensors ◽  
Near Infrared ◽  
Detailed Comparison ◽  
Arrayed Waveguide Gratings ◽  
Interferometric Sensors ◽  
Fiber Technology ◽  
Infrared Spectral ◽  
Reflection Gratings

Optical interferometric sensors have acquired significant importance in metrology and information technology, especially in terms of their potential application in launching size, selectivity, sensitivity, resolution, spectral tuning ranges, efficiency, and cost. However, these demands are often contradictory and counteract one another, and are thus difficult to simultaneously fulfill during their interaction. This review focuses on a detailed comparison of seven different strongly miniaturized sensor concepts investigating the limits of these demands. For the visible and near-infrared spectral range, seven optical sensors were reviewed based on the following methodologies: classical optical transmission and reflection gratings, arrayed waveguide gratings, static Fabry–Pérot (FP) filter arrays, MEMS tunable FP interferometers, MEMS tunable photonic crystals, plasmonic filters, and fiber tip sensors. The comparison between the selected concepts concentrates on (i) the minimum space required for a particular spectral range, (ii) resolution, (iii) the integration in optical fiber technology, (iv) tunability to save space, (v) efficiency in using available light, (vi) multiplexing, (vii) miniaturization limits, and (viii) the potential of nanoimprint for cost reduction. Technologies for enhancing efficiency to obtain more available light and their applicability to the different methodologies were studied.

scholarly journals KOOLS–IFU: Kyoto Okayama Optical Low-dispersion Spectrograph with optical-fiber Integral Field Unit

2019 ◽  
Vol 71 (5) ◽  
Author(s):  
Kazuya Matsubayashi ◽  
Kouji Ohta ◽  
Fumihide Iwamuro ◽  
Ikuru Iwata ◽  
Eiji Kambe ◽  
...  
Keyword(s):  
Optical Fiber ◽  
Gamma Ray ◽  
Field Of View ◽  
Resolving Power ◽  
Optimal Conditions ◽  
Total Field ◽  
Fiber Array ◽  
Field Unit ◽  
Low Dispersion ◽  
Integral Field

Abstract Observations of transient objects, such as short gamma-ray bursts and electromagnetic counterparts of gravitational wave sources, require prompt spectroscopy. To carry out prompt spectroscopy, we have developed an optical-fiber integral field unit (IFU) and connected it with an existing optical spectrograph, KOOLS. KOOLS–IFU was mounted on the Okayama Astrophysical Observatory 188 cm telescope. The fiber core and cladding diameters of the fiber bundle are 100 μm and 125 μm, respectively, and 127 fibers are hexagonally close-packed in the sleeve of the two-dimensional fiber array. We conducted test observations to measure the KOOLS–IFU performance and obtained the following conclusions: (1) the spatial sampling is ${2{^{\prime\prime}_{.}}34}$$\, \pm \,$${0{^{\prime\prime}_{.}}05}$ per fiber, and the total field of view is ${30{^{\prime\prime}_{.}}4}$$\, \pm \,$${0{^{\prime\prime}_{.}}65}$ with 127 fibers; (2) the observable wavelength and the spectral resolving power of the grisms of KOOLS are 4030–7310 Å and 400–600, 5020–8830 Å and 600–900, 4160–6000 Å and 1000–1200, and 6150–7930 Å and 1800–2400, respectively; and (3) the estimated limiting magnitude is 18.2–18.7 AB mag during 30 min exposure under optimal conditions.

scholarly journals Optical Spectrophotometry of Nova PW Vulpeculae

1990 ◽  
Vol 122 ◽  
pp. 159-160 ◽  
Author(s):  
J. Mikołajewska ◽  
M. Mikołajewski
Keyword(s):  
Spectral Sensitivity ◽  
Spectral Range ◽  
Atmospheric Extinction ◽  
Absolute Flux ◽  
Classical Nova ◽  
The Absolute ◽  
Cassegrain Telescope ◽  
Optical Spectrophotometry ◽  
Low Dispersion ◽  
Flux Calibration

PW Vul (Nowa Vul 1984 #1) was a slow classical nova which began its outburst in July 1984 and reached optical maximum in the first week of August 1984. Eight low dispersion spectra (160 A/mm) in the blue spectral range (λλ3400-5100 A) were secured between October 1984 and July 1985, with the CCS spectrograph equipped with 3.5 arcsec aperture image slicer and mounted on 90 cm Schmidt-Cassegrain telescope at Toruń Observatory. Kodak IIa-O plates were used. In addition two moderate dispersion (40 A/mm) spectra in the Hγ-Hβ range were obtained on 28 October and 3 November 1984, using the same instrumentation. Standard stars were observed on each night to remove the influence of spectral sensitivity of the photographic emulssion and atmospheric extinction. The calibration of the absolute flux scale was performed by comparing synthetic B magnitudes calculated from our spectra with published B photometry of PW Vul (Voloshina 1985, Noskova et al. 1985, Kolotilov and Noskova 1986). The accuracy of the flux calibration is ±0.1 mag.

Low-dispersion optical fiber for the UV region: Method of monitoring the strength

2004 ◽  
Vol 71 (4) ◽  
pp. 258
Author(s):  
K. V. Dukel'skii ◽  
Yu. N. Kondrat'ev ◽  
V. S. Shevandin
Keyword(s):  
Optical Fiber ◽  
Region Method ◽  
Low Dispersion

scholarly journals Spectrophotometry of Shell Galaxies

1987 ◽  
Vol 127 ◽  
pp. 463-464
Author(s):  
W.D. Pence
Keyword(s):  
Spectral Range ◽  
Surface Brightness ◽  
Low Dispersion

Low dispersion spectra of two shell galaxies, NGC 3923 and NGC 3051, have been obtained covering the 5300Å to 10000Å spectral range. These long-slit spectra go through the nucleus of each galaxy and also through 12 shells in NGC 3923 and through 3 shells in NGC 3051. the main results are:1) In NGC 3051 the surface brightness of the 2 inner shells is nearly constant with radius. These plateaus of luminosity have very abrupt outer cutoffs but have no detectable inner limits.

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