JournalTOCs

Advances in Optical Technologies
Journal Prestige (SJR): 0.214

Citation Impact (citeScore): 1
Number of Followers: 3

This is an Open Access Journal

Open Access journal
ISSN (Print) 1687-6393 - ISSN (Online) 1687-6407
Published by Hindawi

[340 journals]

Microfluidic Optical Shutter Flexibly - Actuated via
Electrowetting-on-Dielectrics with
- Abstract: Tunable microoptics deals with devices of which the optical properties can be changed during operation without mechanically moving solid parts. Often a droplet is actuated instead, and thus tunable microoptics is closely related to microfluidics. One such device/module/cell type is an optical shutter, which is moved in or out of the path of the light. In our case the transmitting part comprises a moving transparent and electrically conductive water droplet, embedded in a nonconductive blackened oil, that is, an opaque emulsion with attenuation of 30 dB at 570 nm wavelength over the 250 μm long light path inside the fluid (15 dB averaged over the visible spectral range). The insertion loss of the cell is 1.5 dB in the “open shutter” state. The actuation is achieved via electrowetting-on-dielectrics (EWOD) with rectangular AC voltage pulses of V peak-to-peak at 1 kHz. To flexibly allow for horizontal, vertical, and diagonal droplet movement in the upright x-y plane, the contact structures are prepared such that four possible stationary droplet positions exist. The cell is configured as two capacitors in series (along the axis), such that EWOD forces act symmetrically in the front and back of the 60 nl droplet with a response time of
  PubDate: Sun, 31 Dec 2017 11:34:33 +000
Finite Element Analysis of Thermal Effects in Diode End-Pumped Solid-State
Lasers
- Abstract: Thermal effects are the main obstacle to getting high power and good beam quality in diode end-pumped solid-state lasers. In this work, a theoretical investigation of thermal effects in single and dual end-pumped solid-state lasers is carried out using finite element analysis (FEA) for a selected number of widely used laser producing materials, namely, Nd:YAG, Yb:YAG, and Nd:KGW. Crystals with different dimensions are also investigated both in single and in dual end-pumped configuration. Finally, the effect of using composite crystals on thermal lensing is investigated. An experiment to measure the thermal focal length for two different crystals was carried out and a comparison with FEA computed focal length of the thermal lens is made. In all cases studied in this work, results show clear effects of thermal lensing with some differences depending on crystal type, pump power, and size.
  PubDate: Mon, 10 Apr 2017 07:43:05 +000
Long-Term Structural Modification of Water under Microwave Irradiation:
Low-Frequency Raman Spectroscopic Measurements
- Abstract: Raman scattering has been used to study the influence of 2.45 GHz microwave on the structure of water. It has been shown that treatment of the distilled water samples by electromagnetic field leads to long-term changes in the vibrational density of states. It was established that the retention time of structural changes of the water samples depends on the sample volume. The experimental results have been interpreted on the basis of the percolation model. It has been suggested that the change in the chemical composition of the water treated by microwaves can lead to a change in the structure of the percolation cluster formed by the network of hydrogen bonds. The time of the equilibrium structure recovery of the percolation cluster after termination of the microwaves depends on the cluster size and is much slower than the recovery in the chemical composition of water.
  PubDate: Tue, 28 Feb 2017 07:24:59 +000
Comparison of the Optical Amplifiers EDFA and SOA Based on the BER and
-Factor in C-Band
- Abstract: Currently it is not possible to create a fully optical communication system without a software tool which simulates an optical communication line in real conditions prior to its construction. The aim of this article is to establish a comparison between the EDFA (erbium doped fibre amplifier) and SOA (semiconductor optical amplifier) optical amplifiers in the WDM (wavelength division multiplexing) system. The system contains a four-channel WDM with speed of 10 Gbps and optical fibre with length of 80 km. Simulations are conducted in the programme environment “OptSim.” The quality of the optical communication system is evaluated by the BER (bit error rate) and -factor for individual wavelengths, namely, of 1558 nm and 1562 nm, which are within the C-band.
  PubDate: Mon, 09 Jan 2017 13:46:51 +000

HOME > Browse the 73 Subjects covered by JournalTOCs
Subject	Total Journals