Frequency: Quarterly E- ISSN: 2277-6303 P- ISSN: Awaited Abstracted/ Indexed in: Ulrich's International Periodical Directory, Google Scholar, SCIRUS
"Inventi Impact: Optical Technologies" is the peer reviewed journal of Engineering & Technology. It has the research and review paper related to optical engineering and technologies, optical instruments and computational optics useful to engineers, researchers, physicists and mathematicians.
Optical wireless power transmission (OWPT) is a promising technology for remote energy supply, especially for powering Internet of things (IoT) terminals. Light-emitting diode (LED)-based power sources of OWPT are attractive for the development of high-performance systems without the constraints of safety issues. In this paper, the electricity output of a near-infrared LED-OWPT is significantly improved. The saturation output caused by the small lens aperture in the LED array collimation scheme was analyzed. The experiment achieved a maximum electricity output of more than 1 W from a 50 × 50 mm2 GaAs solar cell at 1 m transmission distance. In addition, the thermal features also proved the feasibility of a high-output LED-OWPT system for practical applications....
The BP/InSe heterojunction has attracted the attention of many fields in successful combined high hole mobility of black phosphorus (BP) and high electron mobility of indium selenide (InSe), and enhanced the environmental stability of BP. Nevertheless, photonics research on the BP/InSe heterostructure was insufficient, while both components are considered promising in the field. In this work, a two-dimensional (2D) BP/InSe heterostructure was fabricated using the liquidphase exfoliation method. Its linear and non-linear optical (NLO) absorption was characterized by ultraviolet−visible−infrared and Open-aperture Z-scan technology. On account of the revealed superior NLO properties, an SA based on 2D BP/InSe was prepared and embedded into an erbiumdoped fiber laser, traditional soliton pulses were observed at 1.5 μm with the pulse duration of 881 fs. Furthermore, harmonic mode locking of bound solitons and dark-bright soliton pairs were also obtained in the same laser cavity due to the cross-coupling effect. The stable mode-locked operation can be maintained for several days, which overcome the low air stability of BP. This contribution further proves the excellent optical properties of 2D BP/InSe heterostructure and provides new probability of developing nano-photonics devices for the applications of double pulses laser source and long-distance information transmission....
This paper presents an automatic optical equalizer based on a pair of in-house developed high efficiency, acousto-optic variable\r\noptical attenuators (AO-VOAs). The system is polarization insensitive and presents a wide bandwidth compatible with coarse\r\nwavelength division multiplexing (CWDM) requirements: 340 nm. The system operation is automatic and bidirectional and\r\nequalization is obtained in one single iteration of algorithm loop....
OFDM modulated millimeter wave (mm-wave) at 60GHz. In order to improve transmission of this system, the discrete Fourier\ntransform spread (DFT-Spread) technology and the averaging of the channel frequency response (H-averaging) technology are\napplied. The DFT-Spread technology helps to reduce the peak-to-average power ratio (PAPR) of the OFDM signal, and the Haveraging\ntechnology helps to optimize channel estimation.This is the first time that the two kinds of technologywere used together\nin this reverse modulation system. According to the simulation, the 22Gbit/s 16QAM-OFDM at 60GHz can be generated and\ntransmitted for 90km fiber transmission under the soft decision forward error correction (SD-FEC) threshold 3.8Ã?10-3.The results\nshow that the two jointed DSP algorithms can improve the reverse modulation system transmission performance obviously...
The structural modification of Ba0.5Sr0.5TiO3 (BST) nanocatalyst was successfully synthesized via sol-gel process. The BST\ncatalyst was modified by A-site (A-BST), A-B-site (A-B-BST), and B-site (B-BST) in order to investigate the effect of structurally\nmodified BST catalyst for photocatalytic decolorization of methylene blue. The structurally modified BST catalysts can increase\nthe non radiation energy such as phonon energy compared to that of BST one. The partial incorporation of the A-BST catalyst\nwas evidenced by the higher-ordered structure by increasing number of Ti4+ ions and the lattice oxygen. The A-B-BST and ABST\ncatalysts were given more electron-transfer in the TiO6 than that of BST and B-BST catalysts, respectively. The A-B-BST\ncatalyst promoted the oxidation of the lattice oxygen by holes capturing to form the chemisorbed oxygen, presenting the highest\nphotobleaching activity of methylene blue. On the other hand, more oxygen vacancies recombination of BST catalyst compared to\nthat of structurally modified BST catalysts presented the reduction of photocatalytic activity....
A monochromatic continuous millimeter-wave imaging system coupled with an infrared temperature sensor has been used to investigate artistic objects such as painting artworks or antiquities preserved at the museum of Aquitaine. Especially, 2D and 3D analyses have been performed in order to reveal the internal structure of a nearly 3500-year-old sealed Egyptian jar....
Various applications require an antenna to provide coverage in the azimuthal plane while still retaining a\nlow profile. Transformation Optics method can be used to provide novel solutions to fulfill this objective. In this paper,\nthe design of dielectric superstrate inspired from Transformation Optics has been reported which completely reorients\nthe electromagnetic waves emanating from a directive antenna in the azimuthal plane. The physical space is modeled\nusing a virtual space composed of two opposed quarter circles. It is shown analytically that a dielectric-only solution\ncan be obtained from the transformation relations. Use of shift and compression factors has been applied to the\nmaterial parameter profile to achieve the reorientation. A full wave solution has been presented which reorients\nthe radiation pattern of a classical patch antenna in the azimuthal plane. The solution can be fabricated from isotropic\ndielectric materials....
This paper presents a method for gas concentration determination based on the measurement of the refractive index dispersion of a gas near the gas resonance in the near-infrared region (NIR). The gas refractive index dispersion line shape is reconstructed from the variation in the spectral interference fringesâ?? periods, which are generated by a low-finesse Fabry-Perot interferometer during the DFB diodeâ??s linear-over-time optical frequency sweep around the gas resonance frequency. The entire sensing system was modeled and then verified experimentally, for an example of a low concentration methane-air mixture. We demonstrate experimentally a refractive index dispersion measurement resolution of ..............
The key technology and main difficulty for optical fiber intrusion pre-warning systems\n(OFIPS) is the extraction of harmful-intrusion signals. After being processed by a phase-sensitive\noptical time-domain reflectometer (-OTDR), vibration signals can be preliminarily extracted.\nGenerally, these include noises and intrusions. Here, intrusions can be divided into harmful and\nharmless intrusions. With respect to the close study of signal characteristics, an effective extraction\nmethod of harmful intrusion is proposed in the paper. Firstly, in the part of the background\nreconstruction, all intrusion signals are first detected by a constant false alarm rate (CFAR). We then\nreconstruct the backgrounds by extracting two-part information of alarm points, time and amplitude.\nThis ensures that the detection background consists of intrusion signals. Secondly, in the part of the\ntwo-dimensional Kolmogorov-Smirnov (K-S) test, in order to extract harmful ones from all extracted\nintrusions, we design a separation method. It is based on the signal characteristics of harmful\nintrusion, which are shorter time interval and higher amplitude. In the actual OFIPS, the detection\nmethod is used in some typical scenes, which includes a lot of harmless intrusions, for example\nconstruction sites and busy roads. Results show that we can effectively extract harmful intrusions....
The work presented in this paper shows that Fiber Bragg Grating (FBG) optical fiber sensors\ncan potentially be used as receivers in a long-range guided wave torsional-mode pipe inspection\nsystem. Benefits over the conventional pulse-echo method arise due to reduced total travel distance\nof the ultrasonic guided wave reflections, since reflections from defects and structural features do not\nneed to propagate a full round trip back to the transmitting collar. This is especially important in\npipe configurations with high attenuation, such as coated and buried pipelines. The use of FBGs as\nreceivers instead of conventional piezoelectric or magnetostrictive elements also significantly reduces\ncabling, since multiple FBG receivers can be placed along a single optical fiber which has a diameter\non the order of only around 100 �¼m. The basic approach and sample results are presented in the\npaper. Additionally, a brief overview of some topics in ultrasonic guided waves is presented as a\nbackground to understand the inspection problem presented here....
Loading....