New Non-Oxide Glasses for Optical Waveguiding

1989 ◽  
Vol 152 ◽  
Author(s):  
Jacques Lucas

ABSTRACTThe first generation of infrared optical waveguides operating in the mid I.R. region 0.3 to 4 μm is made from fluoride glasses based on zirconium tetrafluoride. A new family of vitreous materials based on indium fluoride appears to be also promising candidate. The state of art in the field including performances and limitations of these optical fibers will be described. A new class of heavy halide glasses based on tellurium chloride, bromide or iodide is presented in relation with their large optical transmission range covering the 8–12 μm region. First attempts in fiber preparation and planar waveguides deposition will be discussed and compared with the traditional chalcogenide glasses.

1995 ◽  
Vol 392 ◽  
Author(s):  
S. Raoux ◽  
S. Anders ◽  
K. M. Yu ◽  
I. C. Ivanov ◽  
I. G. Brown

AbstractWe describe a novel means for the production of optically active planar waveguides. The technique makes use of a low energy plasma deposition. Cathodic-arc-produced metal plasmas are used for the metallic components of the films and gases are added to form compound films. Here we discuss the synthesis of A12-xErxO3 thin films. The erbium concentration (x) can vary from 0 to 100% and the thickness of the film can be from Angstroms to microns. In such material, at high active center concentration (x=l% to 20%), erbium ions give rise to room temperature 1.53μm emission which has minimum loss in silica-based optical fibers. With this technique, multilayer integrated planar waveguide structures can be grown, such as Al2O3/Al2-xErO3/A12O3/Si, for example.


1985 ◽  
Vol 60 ◽  
Author(s):  
T. Miyashita

AbstractRecent advances of glass materials and fabrication processes will be reviewed in the field of guided-wave technology. A variety of optical fibers and guided-wave devices are in development by using high-silica and non-silica glasses. Following the successful development of silica fiber, a new family of optical fibers is being investigated by using non-silica glasses such as fluoride and chalcogenide glasses, which operate at mid-infrared wavelength range and offer the potential of ultra-low loss. High-silica channel waveguides are fabricated by processing a SiO2TiO2 planer waveguide on a silicon substrate. These are applied to various guided wave optical circuits such as switch and wavelength-division multi/demultiplexer, which would be used for the construction of optical communication systems. The materials and processing techniques influencing optical guided-wave performance are described.


Symmetry ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 908
Author(s):  
Perla Celis ◽  
Rolando de la Cruz ◽  
Claudio Fuentes ◽  
Héctor W. Gómez

We introduce a new class of distributions called the epsilon–positive family, which can be viewed as generalization of the distributions with positive support. The construction of the epsilon–positive family is motivated by the ideas behind the generation of skew distributions using symmetric kernels. This new class of distributions has as special cases the exponential, Weibull, log–normal, log–logistic and gamma distributions, and it provides an alternative for analyzing reliability and survival data. An interesting feature of the epsilon–positive family is that it can viewed as a finite scale mixture of positive distributions, facilitating the derivation and implementation of EM–type algorithms to obtain maximum likelihood estimates (MLE) with (un)censored data. We illustrate the flexibility of this family to analyze censored and uncensored data using two real examples. One of them was previously discussed in the literature; the second one consists of a new application to model recidivism data of a group of inmates released from the Chilean prisons during 2007. The results show that this new family of distributions has a better performance fitting the data than some common alternatives such as the exponential distribution.


Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1972
Author(s):  
Agnieszka Gierej ◽  
Thomas Geernaert ◽  
Sandra Van Vlierberghe ◽  
Peter Dubruel ◽  
Hugo Thienpont ◽  
...  

The limited penetration depth of visible light in biological tissues has encouraged researchers to develop novel implantable light-guiding devices. Optical fibers and waveguides that are made from biocompatible and biodegradable materials offer a straightforward but effective approach to overcome this issue. In the last decade, various optically transparent biomaterials, as well as different fabrication techniques, have been investigated for this purpose, and in view of obtaining fully fledged optical fibers. This article reviews the state-of-the-art in the development of biocompatible and biodegradable optical fibers. Whilst several reviews that focus on the chemical properties of the biomaterials from which these optical waveguides can be made have been published, a systematic review about the actual optical fibers made from these materials and the different fabrication processes is not available yet. This prompted us to investigate the essential properties of these biomaterials, in view of fabricating optical fibers, and in particular to look into the issues related to fabrication techniques, and also to discuss the challenges in the use and operation of these optical fibers. We close our review with a summary and an outline of the applications that may benefit from these novel optical waveguides.


2017 ◽  
Vol 6 (2) ◽  
Author(s):  
Andrea Ravagli ◽  
Christopher Craig ◽  
John Lincoln ◽  
Daniel W. Hewak

AbstractChalcogenide glasses are emerging as important enabling materials for low-cost infrared imaging by virtue of their transparency in the key short-wave infrared (SWIR) to long-wave infrared (LWIR) bands and the ability to be mass produced and molded into near-net shape lenses. In this paper, we introduce a new family of chalcogenide glasses, which offer visible as well as infrared transmission and improved thermal and mechanical properties. These glasses are based on Ga


2007 ◽  
Vol 1054 ◽  
Author(s):  
Ruth Houbertz ◽  
Herbert Wolter ◽  
Volker Schmidt ◽  
Ladislav Kuna ◽  
Valentin Satzinger ◽  
...  

ABSTRACTThe integration of optical interconnects in printed circuit boards (PCB) is a rapidly growing field worldwide due to a continuously increasing need for high-speed data transfer. There are any concepts discussed, among which are the integration of optical fibers or the generation of waveguides by UV lithography, embossing, or direct laser writing. The devices presented so far require many different materials and process steps, but particularly also highly-sophisticated assembly steps in order to couple the optoelectronic elements to the generated waveguides. In order to overcome these restrictions, an innovative approach is presented which allows the embedding of optoelectronic components and the generation of optical waveguides in only one optical material. This material is an inorganic-organic hybrid polymer, in which the waveguides are processed by two-photon absorption (TPA) processes, initiated by ultra-short laser pulses. In particular, due to this integration and the possibility ofin situpositioning the optical waveguides with respect to the optoelectronic components by the TPA process, no complex packaging or assembly is necessary. Thus, the number of necessary processing steps is significantly reduced, which also contributes to the saving of resources such as energy or solvents. The material properties and the underlying processes will be discussed with respect to optical data transfer in PCBs.


2017 ◽  
Vol 17 (2) ◽  
pp. 36
Author(s):  
Dadin Mahmudin ◽  
Shobih ◽  
Pamungkas Daud ◽  
Yusuf Nur Wijayanto

Optical waveguides are important for guiding lightwave from a place to other places. Propagation and insertion losses of the optical waveguides should be considered to be in low values. Recently, optical waveguides with circular structures, which are optical fibers, are used widely for guiding lightwave in long-distance optical communication with very low propagation and insertion losses. Simultaneously, optical waveguides with planar structure are also developed for short distance communication in optical devices. We have reported design and analysis of the planar optical waveguides. In this paper, fabrication of planar optical waveguides using a polyimide material on thin silicon dioxide combined with the silicon substrate is reported. The polyimide material is used for the core of the optical waveguides. The silicon dioxide located on the silicon substrate and the air is used for cladding of the optical waveguides. Fabrication of the optical waveguides such as oxidation, photoresist coating, masking, ultra-violet exposure, and etching was done. The fabricated optical waveguides were characterized physically using a standard microscope and scanning electron microscope (SEM). The fabrication processes and characterization results are reported and discussed in detail.


Author(s):  
Longfei Liu ◽  
Xiaoyuan Yang ◽  
Bin Wei ◽  
Liqiang Wu

Periodic sequences over finite fields, constructed by classical cyclotomic classes and generalized cyclotomic classes, have good pseudo-random properties. The linear complexity of a period sequence plays a fundamental role in the randomness of sequences. In this paper, we construct a new family of quaternary generalized cyclotomic sequences with order [Formula: see text] and length [Formula: see text], which generalize the sequences constructed by Ke et al. in 2012. In addition, we determine its linear complexity using cyclotomic theory. The conclusions reveal that these sequences have high linear complexity, which means they can resist linear attacks.


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