Journal articles: 'Optical design techniques'

1

Walker, S. D., M. Li, A. C. Boucouvalas, D. G. Cunningham, and A. N. Coles. "Design techniques for subcarrier multiplexed broadcast optical networks." IEEE Journal on Selected Areas in Communications 8, no. 7 (1990): 1276–84. http://dx.doi.org/10.1109/49.59127.

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Vieira, M., M. A. Vieira, P. Louro, and V. Silva. "Optical Filter Design Using Background Wavelength Processing Techniques." Plasmonics 8, no. 1 (August 29, 2012): 121–27. http://dx.doi.org/10.1007/s11468-012-9434-5.

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Amitai, Y., and A. A. Friesem. "Design of holographic optical elements by using recursive techniques." Journal of the Optical Society of America A 5, no. 5 (May 1, 1988): 702. http://dx.doi.org/10.1364/josaa.5.000702.

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Swain, Digendranath, Jeby Philip, and S. Annamala Pillai. "Assessment of a Complex Aerospace Design through Optical Techniques." Applied Mechanics and Materials 592-594 (July 2014): 1006–10. http://dx.doi.org/10.4028/www.scientific.net/amm.592-594.1006.

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This paper reports the design assessment carried out on a subassembly of an advanced rocket using experimental techniques. The design was very complex and critical, since a cylindrical shell had a square cutout on the axial-hoop plane interacting with a notch in the axial-radial plane. Herein, two optical techniques have been employed for assessing the interaction between the notch and the cutout, and their individual contributions to the strain-field. Initially, a photoelastic model was studied to estimate the stresses at the notch tip. Subsequently, DIC was employed for measuring strains at the notch during the ground based testing of the actual component. The outcomes of these two experiments showed that the effect of the cutout to the strain concentration was negligible due to the extra stiffness provided by other assemblies.

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Zhang, Li, Tao Qian, Xingyu Zhu, Zhongli Hu, Mengfan Wang, Liya Zhang, Tao Jiang, Jing-Hua Tian, and Chenglin Yan. "In situ optical spectroscopy characterization for optimal design of lithium–sulfur batteries." Chemical Society Reviews 48, no. 22 (2019): 5432–53. http://dx.doi.org/10.1039/c9cs00381a.

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Recent advances in optimal design of lithium–sulfur batteries with the aid of in situ optical spectroscopic techniques, including Raman, infrared and ultraviolet-visible spectroscopies, are systematically summarized.

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Borella, Andrea, Giovanni Cancellieri, and Franco Chiaraluce. "Design techniques of two-layer architectures for WDM optical networks." International Journal of Communication Systems 14, no. 2 (2001): 171–88. http://dx.doi.org/10.1002/dac.448.

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Lee, Yang-Han, Jyh Yuan Wang, and Shyh-Lin Tsao. "Design of packet-switched network using optical signal processing techniques." Microwave and Optical Technology Letters 23, no. 2 (October 20, 1999): 104–9. http://dx.doi.org/10.1002/(sici)1098-2760(19991020)23:2<104::aid-mop13>3.0.co;2-p.

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Cogalan, T., H. Haas, and E. Panayirci. "Optical spatial modulation design." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, no. 2169 (March 2, 2020): 20190195. http://dx.doi.org/10.1098/rsta.2019.0195.

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Visible light communication (VLC) systems are inherently signal-to-noise ratio (SNR) limited due to link budget constraints. One favourable method to overcome this limitation is to focus on the pre-log factors of the channel capacity. Multiple-input multiple-output (MIMO) techniques are therefore a promising avenue of research. However, inter-channel interference in MIMO limits the achievable capacity. Spatial modulation (SM) avoids this limitation. Furthermore, the performance of MIMO systems in VLC is limited by the similarities among spatial channels. This limitation becomes particularly severe in intensity modulation/direct detection (IM/DD) systems because of the lack of phase information. The motivation of this paper is to propose a system that results in a multi-channel transmission system that enables reliable multi-user optical MIMO SM transmission without the need for a precoder, power allocation algorithm or additional optics at the receiver. A general bit error performance model for the SM system is developed for an arbitrary number of light-emitting diodes (LEDs) in conjunction with pulse amplitude modulation. Based on this model, an LED array structure is designed to result in spatially separated multiple channels by manipulating the transmitter geometry. This article is part of the theme issue ‘Optical wireless communication’.

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Elhelw, Ahmed Refaat, Abd El–Naser A. Mohamed, Ahmed N. Rashed, and Mohamed Z. Elsiefy. "Design of High Speed Optical Fiber Cables and Transmission Techniques in Advanced Optical Networks." Menoufia Journal of Electronic Engineering Research 29, no. 1 (January 1, 2020): 71–77. http://dx.doi.org/10.21608/mjeer.2020.69185.

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Chiwo, F. S., and And F. J. Gonzalez. "Design and implementation of a low-cost portable Raman spectrometer." Revista Mexicana de Física 65, no. 3 (May 7, 2019): 274. http://dx.doi.org/10.31349/revmexfis.65.274.

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Non-invasive medical diagnosis has become popular due to the possibility of detecting illnesses in vivo and in real time this technique, often referred to as "optical biopsy", comprises several optical techniques such as thermography, diffuse reflectance spectroscopy, optical coherence tomography and Raman spectroscopy among others. Particularly Raman spectroscopy is an optical technique based on the inelastic scattering of light that can detect disease markers, this technique has been successfully used to detect several types of diseases, however the high price of a Raman spectrometer makes it difficult for the medical community to adopt its use as a common diagnostic procedure. In this work a Raman spectroscopy system was designed and fabricated from low-cost readily available components. The system was characterized and the Raman spectra obtained was compared to commercial systems. Results show that it is possible to fabricate a custom Raman system with the desired optical configuration for non-invasive optical diagnosis at low costs and portable size.

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Li, Gang, and Chang-Hong Liang. "DESIGN TECHNIQUES FOR MICROWAVE DIPLEXERS." Progress In Electromagnetics Research B 2 (2008): 103–13. http://dx.doi.org/10.2528/pierb07102906.

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Singh, Chaturi, Joseph John, Y. N. Singh, and K. K. Tripathi. "Indoor Optical Wireless Systems: Design Challenges, Mitigating Techniques and future Prospects." IETE Technical Review 21, no. 2 (March 2004): 101–17. http://dx.doi.org/10.1080/02564602.2004.11417136.

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Bhattacharya, Shanti. "Simplified mesh techniques for design of beam-shaping diffractive optical elements." Optik 119, no. 7 (May 2008): 321–28. http://dx.doi.org/10.1016/j.ijleo.2006.12.004.

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Ghanim Wadday, Ahmed Ghanim Wadday, Faris Mohammed Ali, and Hayder Jawad Mohammed Albattat. "Design of high scalability multi-subcarrier rof hybrid system based on optical CDMA/TDM." Indonesian Journal of Electrical Engineering and Computer Science 21, no. 2 (February 1, 2021): 927. http://dx.doi.org/10.11591/ijeecs.v21.i2.pp927-937.

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<span>The technology of radio over fiber (RoF) regard a crucial point to solve problems in wireless communication system. As well as, the growth of internet applications also reveals a tremendous increase in bandwidth for different applications. Therefore, the development of optical networks is very important that have maximum bandwidth by using different multiple access techniques. Optical code division multiple access (OCDMA) technique has considered as a good solution for high bandwidth network. Hybrid optical systems of OCDMA and time division multiplexing (OTDM) has been proposed in this paper to increase the number of simultaneous users. The results of hybrid OCDMA and OTDM system demonstrate that this system can make a considerable increase in the network scalability while ensuring sufficient data rate and an acceptable bit error rate. Where M-user OCDMA signals can be transmitted in different channels of an OTDM system. Due to its wide band facility compared with other access techniques, OCDMA used here. In addition to its high scalability for our radio network, the OTDM and SCM utilized. The combination of these efficient access technique and powerful time-sharing media are lead to increase the framework system scalability.</span>

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Prasad, Alisha, Syed Mohammad Abid Hasan, and Manas Ranjan Gartia. "Optical Identification of Middle Ear Infection." Molecules 25, no. 9 (May 9, 2020): 2239. http://dx.doi.org/10.3390/molecules25092239.

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Ear infection is one of the most commonly occurring inflammation diseases in the world, especially for children. Almost every child encounters at least one episode of ear infection before he/she reaches the age of seven. The typical treatment currently followed by physicians is visual inspection and antibiotic prescription. In most cases, a lack of improper treatment results in severe bacterial infection. Therefore, it is necessary to design and explore advanced practices for effective diagnosis. In this review paper, we present the various types of ear infection and the related pathogens responsible for middle ear infection. We outline the conventional techniques along with clinical trials using those techniques to detect ear infections. Further, we highlight the need for emerging techniques to reduce ear infection complications. Finally, we emphasize the utility of Raman spectroscopy as a prospective non-invasive technique for the identification of middle ear infection.

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Sun, Ke Xue, Xian Jun Li, Shao Fang Zhang, and Hao Zheng. "A Design Technique and Structure for Optical Fibre Vibration Sensor." Applied Mechanics and Materials 687-691 (November 2014): 3462–65. http://dx.doi.org/10.4028/www.scientific.net/amm.687-691.3462.

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This paper reviewed techniques of vibration sensors, studied structure and working principle of phase modulated optical fiber vibration sensor, and designed a new structure of non-contact optical vibration sensor. Use this structure, expect accuracy of 0.1um can be obtained in the range of 1mm. At the same time, this system is simple, anti-interference ability, high reliability and ease of practical.

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Campbell, Sawyer, Eric Whiting, Ronald Jenkins, Pingjuan Werner, and Douglas Werner. "Optimization and Inverse-design Techniques for Metalens Synthesis." Applied Computational Electromagnetics Society 35, no. 11 (February 4, 2021): 1334–35. http://dx.doi.org/10.47037/2020.aces.j.351136.

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Phase-gradient metasurfaces enable designers to tailor the behavior of electromagnetic waves at surfaces by exploiting the generalized form of Snell’s law. This ability has led to the investigation of metalenses which have the potential to significantly reduce the size, weight, and power (SWaP) of conventional optical systems. While traditional lenses are made from individual glasses, metalenses are comprised of patterned meta-atom unit Cells which are arranged in such a way so as to give the metalens its desired behavior. Therefore, any metalens’s performance is ultimately determined by that of its underlying unit cell components. However, designing meta-atoms that simultaneously achieve high performance over wide frequency bandwidths and fields-of-view is an extremely challenging problem that is best addressed with powerful optimization and inverse-design techniques.

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García-Botella, Angel, Lun Jiang, and Roland Winston. "Flowline Optical Simulation to Refractive/Reflective 3D Systems: Optical Path Length Correction." Photonics 6, no. 4 (September 28, 2019): 101. http://dx.doi.org/10.3390/photonics6040101.

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Nonimaging optics is focused on the study of techniques to design optical systems for the purpose of energy transfer instead of image forming. The flowline optical design method, based on the definition of the geometrical flux vector J, is one of these techniques. The main advantage of the flowline method is its capability to visualize and estimate how radiant energy is transferred by the optical systems using the concepts of vector field theory, such as field line or flux tube, which overcomes traditional raytrace methods. The main objective this paper is to extend the flowline method to analyze and design real 3D concentration and illumination systems by the development of new simulation techniques. In this paper, analyzed real 3D refractive and reflective systems using the flowline vector potential method. A new constant term of optical path length is introduced, similar and comparable to the gauge invariant, which produces a correction to enable the agreement between raytrace- and flowline-based computations. This new optical simulation methodology provides traditional raytrace results, such as irradiance maps, but opens new perspectives to obtaining higher precision with lower computation time. It can also provide new information for the vector field maps of 3D refractive/reflective systems.

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Zavargo-Peche, Luis, Alejandro Ortega-Monux, Juan Gonzalo Wanguemert-Perez, and Inigo Molina-Fernandez. "FOURIER BASED COMBINED TECHNIQUES TO DESIGN NOVEL SUB-WAVELENGTH OPTICAL INTEGRATED DEVICES." Progress In Electromagnetics Research 123 (2012): 447–65. http://dx.doi.org/10.2528/pier11072907.

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Yang, Jing Song, Xiu Ling He, and Li Xin Li. "Multi-Sensor Life Detection Synergy Platform Design." Applied Mechanics and Materials 442 (October 2013): 520–25. http://dx.doi.org/10.4028/www.scientific.net/amm.442.520.

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Life detection based on a single type of information sources detection technology cannot completely meet the needs of the earthquake relief. The existing life detection techniques are include of acoustic wave life detection, optical life detection and radar life detection. The advantages and existing problems of the three life detection techniques are analyzed. The advantages and present situation of multi-sensor detection synergy technique are given . We explained the platform structure , multi-sensor selection strategy, and information fusion model. Finally, the development direction of life detection technique based on multi-sensor synergy is forecasted. This platform mainly realizes the infrared image and acoustic wave synchronization collection, analysis and processing of both audio life detection and video detection function, make up for the deficiency of the single sensor life detector, can get a more comprehensive and more accurate information about the scene of rescue and living organisms, is more suitable for complex quake rescue environment.

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Isaac, Annie Shalom, and Cornelius Neumann. "Optimization of freeform surfaces using intelligent deformation techniques for LED applications." Advanced Optical Technologies 7, no. 1-2 (April 25, 2018): 67–80. http://dx.doi.org/10.1515/aot-2017-0074.

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AbstractFor many years, optical designers have great interests in designing efficient optimization algorithms to bring significant improvement to their initial design. However, the optimization is limited due to a large number of parameters present in the Non-uniform Rationaly b-Spline Surfaces. This limitation was overcome by an indirect technique known as optimization using freeform deformation (FFD). In this approach, the optical surface is placed inside a cubical grid. The vertices of this grid are modified, which deforms the underlying optical surface during the optimization. One of the challenges in this technique is the selection of appropriate vertices of the cubical grid. This is because these vertices share no relationship with the optical performance. When irrelevant vertices are selected, the computational complexity increases. Moreover, the surfaces created by them are not always feasible to manufacture, which is the same problem faced in any optimization technique while creating freeform surfaces. Therefore, this research addresses these two important issues and provides feasible design techniques to solve them. Finally, the proposed techniques are validated using two different illumination examples: street lighting lens and stop lamp for automobiles.

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Tuckerman, D. B., and D. Benson. "Electrical Design Techniques for MCM-D." Microelectronics International 12, no. 3 (September 1995): 16–22. http://dx.doi.org/10.1108/eb044579.

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Wuibaut, G., G. Bois, M. El Hajem, A. Akhras, and J. Y. Champagne. "Optical PIV and LDV Comparisons of Internal Flow Investigations in SHF Impeller." International Journal of Rotating Machinery 2006 (2006): 1–9. http://dx.doi.org/10.1155/ijrm/2006/69521.

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The paper presents a comparison between two sets of experimental results in a centrifugal flow pump. The tested impeller is the so-called SHF impeller for which many experimental data have been continuously produced to built databases for CFD code validations with various levels of approximation. Measurements have been performed using optical techniques: 2D particle image velocimetry (PIV) technique on an air test model and 2D laser doppler velocimetry (LDV) technique on a water model, both for different flow rates. For the present study, results obtained by these optical techniques are compared together in terms of phase averaged velocity and velocity fluctuations inside the impeller flow passage for design flow rate.

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Singh, Rishabh, Ghanendra Kumar, and Chakresh Kumar. "Impact of encryption and decryption techniques for high speed optical domain." Computer Science and Information Technologies 2, no. 1 (March 1, 2021): 11–15. http://dx.doi.org/10.11591/csit.v2i1.p11-15.

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This project proposes the design of ultrafast communication circuit which can enable the high speed secured data transmission at 50 Gb/s and 100 Gb/s by the use of distributed Raman amplifier, EDFA (Erbium – doped fiber amplifier), filter, single mode fiber along with Fiber Bragg Grating (FBG) and attenuators. The simulation of the suggested optical circuit involves the use of parameters of Raman amplifier and EDFA and other components included in the optical structure. The design also includes the use of encryption and decryption techniques to ensure secured communication. Thus, realization of these circuits at 50 Gb/s and 100 Gb/s will enable the future optical communication applications for ultrafast data transmission to large distances.

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Yao, Jie, Yuan Wang, Kun-Tong Tsai, Zhaowei Liu, Xiaobo Yin, Guy Bartal, Angelica M. Stacy, Yuh-Lin Wang, and Xiang Zhang. "Design, fabrication and characterization of indefinite metamaterials of nanowires." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369, no. 1950 (September 13, 2011): 3434–46. http://dx.doi.org/10.1098/rsta.2011.0159.

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Indefinite optical properties, which are typically characterized by hyperbolic dispersion relations, have not been observed in naturally occurring materials, but can be realized through a metamaterial approach. We present here the design, fabrication and characterization of nanowire metamaterials with indefinite permittivity, in which all-angle negative refraction of light is observed. The bottom-up fabrication technique, which applies electrochemical plating of nanowires in porous alumina template, is developed and demonstrated in achieving uniform hyperbolic optical properties at a large scale. We developed techniques to improve the uniformity and to reduce the defect density in the sample. The non-magnetic design and the off-resonance operation of the nanowire metamaterials significantly reduce the energy loss of electromagnetic waves and make the broad-band negative refraction of light possible.

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Kaur, Jaspreet, Baljeet Kaur, and Kuldeepak Singh. "Design and Performance Investigation of Intersatellite Optical Wireless Communication System Employing Modulation Techniques." Wireless Personal Communications 94, no. 3 (September 12, 2016): 793–807. http://dx.doi.org/10.1007/s11277-016-3651-8.

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Hosseini, Amir, David N. Kwong, Yang Zhang, Harish Subbaraman, Xiaochuan Xu, and Ray T. Chen. "1× N Multimode Interference Beam Splitter Design Techniques for On-Chip Optical Interconnections." IEEE Journal of Selected Topics in Quantum Electronics 17, no. 3 (May 2011): 510–15. http://dx.doi.org/10.1109/jstqe.2010.2099210.

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Solís, D. M., J. M. Taboada, M. G. Araújo, F. Obelleiro, and J. O. Rubiños-López. "Design of optical wide-band log-periodic nanoantennas using surface integral equation techniques." Optics Communications 301-302 (August 2013): 61–66. http://dx.doi.org/10.1016/j.optcom.2013.03.047.

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Bastianini, Filippo, Raffaella Di Sante, Francesco Falcetelli, Diego Marini, and Gabriele Bolognini. "Optical Fiber Sensing Cables for Brillouin-Based Distributed Measurements." Sensors 19, no. 23 (November 26, 2019): 5172. http://dx.doi.org/10.3390/s19235172.

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Brillouin distributed optical fiber sensing (Brillouin D-FOS) is a powerful technology for real-time in situ monitoring of various physical quantities, such as strain, temperature, and pressure. Compared to local or multi-point fiber optic sensing techniques, in Brillouin-based sensing, the optical fiber is interrogated along its complete length with a resolution down to decimeters and with a frequency encoding of the measure information that is not affected by changes in the optical attenuation. The fiber sensing cable plays a significant role since it must ensure a low optical loss and optimal transfer of the measured parameters for a long time and in harsh conditions, e.g., the presence of moisture, corrosion, and relevant mechanical or thermal stresses. In this paper, research and application regarding optical fiber cables for Brillouin distributed sensing are reviewed, connected, and extended. It is shown how appropriate cable design can give a significant contribution toward the successful exploitation of the Brillouin D-FOS technique.

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Li, G., B. Wu, X. W. Dai, and C. H. Liang. "Design Techniques for Asymmetric Dual-Passband Filters." Journal of Electromagnetic Waves and Applications 22, no. 2-3 (January 2008): 375–83. http://dx.doi.org/10.1163/156939308784160785.

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Jalali, Mandana, Hamid Nadgaran, and Daniel Erni. "Semiperiodic Ultra-Broadband Double-Grating to Improve c-Si Thin-Film Solar Cell’s Optical Absorption, through Numerical Structural Optimization." Crystals 9, no. 5 (May 21, 2019): 264. http://dx.doi.org/10.3390/cryst9050264.

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Plasmonic gratings provide effective photon management techniques in thin-film solar cells, capable of extending the optical thickness of the solar cell’s active layer. However, the ultra-broadband nature of such application makes an optimal design of the grating structure quite challenging, since a fully periodic grating operates only in specific spectral ranges. To achieve a more broadband design, semiperiodicity is introduced, which, due to having controllable disorder, is an apt solution in broadband optical applications. In this work, semiperiodic double gratings as a broadband photon management technique are introduced in order to improve the optical absorption of c-Si thin-film solar cells, and optimized through numerical structural optimization. Physical parameters of both front and back gratings are determined taking the spectrally integrated optical absorption as the figure of merit and subsequently a semiperiodic double grating is established through adding defects to the fully periodic structure. It is shown that such semiperiodic structure is capable of enhancing the spectrally integrated optical absorption 88.6 % compared to a reference structure without gratings.

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Spinelli, Sebastiano, Luigina Arcangeli, Ruben Mazzoleni, Massimiliano Rossi, Marco Terraneo, and Roman Windpassinger. "NOPT – New polishing techniques for scalable, light-weighted mirrors of different materials." EPJ Web of Conferences 215 (2019): 03002. http://dx.doi.org/10.1051/epjconf/201921503002.

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In the framework of an assessment of optical polishing techniques, ESA has signed a contract with Media Lario to deliver two 250 mm mirrors with a common optical design to be polished down to very tight surface requirements. NOPT mirrors are respectively made of Zerodur and AlSi alloy with electroless nickel and will they be polished by means of bonnet polishing. Mirrors are light-weighted up to 20kg/m2; the mechanical and optical design is proven to be scalable up to 1m CA surfaces. This paper reviews the mirrors opto-mechanical design, introduce the polishing and metrology strategy while highlighting the differences and the common point in fabricating such mirror in Zerodur and metal.

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Campbell, Sawyer D., David Sell, Ronald P. Jenkins, Eric B. Whiting, Jonathan A. Fan, and Douglas H. Werner. "Review of numerical optimization techniques for meta-device design [Invited]." Optical Materials Express 9, no. 4 (March 20, 2019): 1842. http://dx.doi.org/10.1364/ome.9.001842.

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Tseng, Shin-Pin, Eddy Wijanto, Po-Han Lai, and Hsu-Chih Cheng. "Bipolar Optical Code Division Multiple Access Techniques Using a Dual Electro-Optical Modulator Implemented in Free-Space Optics Communications." Sensors 20, no. 12 (June 24, 2020): 3583. http://dx.doi.org/10.3390/s20123583.

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This study developed a bipolar optical code division multiple access (Bi-OCDMA) technique based on spectral amplitude coding for the formation and transmission of optical-polarized and coded signals over wireless optical channels. Compared with conventional Bi-OCDMA schemes, the proposed free-space optics communication system that uses a dual electro-optical modulator design improves the transmission rate. In theory, multiple access interference can be removed by using correlation subtraction schemes. The experiment results revealed that the proposed system can be employed to accurately extract codewords from an M-sequence and subsequently reconstruct the desired original data. Moreover, the proposed architecture can be implemented easily in simple and cost-effective designs and may be beneficial for broadening the use of Bi-OCDMA schemes in wireless optical communications.

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Rahman, M. Tanjidur, Nusrat Farzana Dipu, Dhwani Mehta, Shahin Tajik, Mark Tehranipoor, and Navid Asadizanjani. "CONCEALING-Gate: Optical Contactless Probing Resilient Design." ACM Journal on Emerging Technologies in Computing Systems 17, no. 3 (June 25, 2021): 1–25. http://dx.doi.org/10.1145/3446998.

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Optical probing, though developed as silicon debugging tools from the chip backside, has shown its capability of extracting secret data, such as cryptographic keys and user identifications, from modern system-on-chip devices. Existing optical probing countermeasures are based on detecting any device modification attempt or abrupt change in operating conditions during asset extraction. These countermeasures usually require additional fabrication steps and cause area and power overheads. In this article, we propose a novel low-overhead design methodology to prevent optical probing. It leverages additional operational logic gates, termed as “CONCEALING-Gates,” inserted as neighbor gates of the logic gates connected to the nets carrying asset signals. The switching activity of the asset carrying logic is camouflaged with the switching activity of the concealing-gate. The input signal and placement in the layout of the concealing-gates must be selected in such a way that they remain equally effective in preventing different variants of optical probing, i.e., electro-optical frequency mapping and Electro-optical probing. The methodology is suitable for the existing ASIC/FPGA design flow and fabrication process, since designing new standard logic cells is not required. We have performed a comprehensive security evaluation of the concealing-gates using a security metric developed based on the parameters that are crucial for optical probing. The attack resiliency of the logic cells, protected by concealing-gates, is evaluated using an empirical study-based simulation methodology and experimental validation. Our analysis has shown that in the presence of concealing-gates, logic cells achieve high resiliency against optical contactless probing techniques.

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Hassan, Gufran A., and Jawad A. Hassan. "Design and study the performance of optical nanoantenna." Al-Qadisiyah Journal for Engineering Sciences 12, no. 2 (June 30, 2019): 84–89. http://dx.doi.org/10.30772/qjes.v12i2.593.

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Recently, the light metallic interaction of nanostructures has grown to be an area of intensive care research due to advances in modern fabrication techniques. Unique effects have been observed in a nanostructure, and their applications have been found in various areas like in the manipulation of light on the nanometer scale. In this paper Nanoantenna has been introduced and invetigated by studing the effect of changing its parameters such as (shape, length, thickness, and the gap distance between two nanostructures) on the response of the nanoantenna (far field directivity, optical resonance frequency, and S-parameter). Here, a bow tie antenna has been chosen and additional parameters have been considered in the simulation, such as antenna thickness and material, and substrate material . The simulations have been generated using computer simulation technology (CST) studio. Optical antenna is performed from a pair of nanoparticles brought in close nearness, these pairs are separated by small gap to make a high electric field in its gap region. This feature can be employed for biosensing or SERS to improve the detection limit and measure the presence of single molecules.

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Chen, Han-Ting, Po-Li Chen, Jenn-Tsong Horng, and Ying-Huei Hung. "Design Optimization for Pin-Fin Heat Sinks." Journal of Electronic Packaging 127, no. 4 (December 21, 2004): 397–406. http://dx.doi.org/10.1115/1.2056572.

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An effective method for performing the thermal optimization of fully confined pin-fin heat sinks under constraints of pressure drop, mass, and space limitations has been successfully developed. This study shows how automated design optimization techniques can be successfully applied to optimal design of pin-fin heat sinks, which allows the thermal engineer to meet several design objectives and constraints simultaneously. The thermal and hydrodynamic models for pin-fin heat sinks have been developed. A statistical method for sensitivity analysis of the design factors, including the size of heat source and sink footprint, conductivity of sink base, fin material, fin pitch, fin diameter, fin height, thickness of sink base, and upstream mass flowrate, is performed to determine the key factors that are critical to the design. A response surface methodology is then applied to establish regression models for the thermal resistance and pressure drop in terms of the design factors with an experimental design. By employing the gradient-based numerical optimization technique, a series of constrained optimal designs can be efficiently performed. Comparisons between these predicted optimal designs and those evaluated by the theoretical calculations and numerical simulations are made with satisfactory agreements.

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Chang, The Nan, and Chun-Hua Chen. "Design techniques applied to partially reflective surface antenna." Microwave and Optical Technology Letters 51, no. 4 (April 2009): 1112–16. http://dx.doi.org/10.1002/mop.24251.

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Hoving, A. M., E. E. de Vries, J. Mikhal, G. J. de Borst, and C. H. Slump. "A Systematic Review for the Design of In Vitro Flow Studies of the Carotid Artery Bifurcation." Cardiovascular Engineering and Technology 11, no. 2 (December 10, 2019): 111–27. http://dx.doi.org/10.1007/s13239-019-00448-9.

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Abstract Purpose In vitro blood flow studies in carotid artery bifurcation models may contribute to understanding the influence of hemodynamics on carotid artery disease. However, the design of in vitro blood flow studies involves many steps and selection of imaging techniques, model materials, model design, and flow visualization parameters. Therefore, an overview of the possibilities and guidance for the design process is beneficial for researchers with less experience in flow studies. Methods A systematic search to in vitro flow studies in carotid artery bifurcation models aiming at quantification and detailed flow visualization of blood flow dynamics results in inclusion of 42 articles. Results Four categories of imaging techniques are distinguished: MRI, optical particle image velocimetry (PIV), ultrasound and miscellaneous techniques. Parameters for flow visualization are categorized into velocity, flow, shear-related, turbulent/disordered flow and other parameters. Model materials and design characteristics vary between study type. Conclusions A simplified three-step design process is proposed for better fitting and adequate match with the pertinent research question at hand and as guidance for less experienced flow study researchers. The three consecutive selection steps are: flow parameters, image modality, and model materials and designs. Model materials depend on the chosen imaging technique, whereas choice of flow parameters is independent from imaging technique and is therefore only determined by the goal of the study.

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XIAO Shang-hui, 肖尚辉, 唐才杰 TANG Cai-jie, 江毅 JIANG Yi, and 汤俊 TANG Jun. "Design on Optical Fiber Methane Sensing Systems Employing Wavelength-Scanning Based Differential Absorption Techniques." ACTA PHOTONICA SINICA 41, no. 12 (2012): 1479–82. http://dx.doi.org/10.3788/gzxb20124112.1479.

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Guo, Y., and S. Liu. "Development in Optical Methods for Reliability Analysis in Electronic Packaging Applications." Journal of Electronic Packaging 120, no. 2 (June 1, 1998): 186–93. http://dx.doi.org/10.1115/1.2792619.

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The mechanical analysis of electronic packaging has significant impact on the system reliability of an electronic device, and, therefore, is critical in packaging design and manufacturing. The main concerns of the mechanical analysis are the thermal strain/stress, interfacial failures, and the fatigue life of components and interconnections. As electronic technology advances, electronic packages are becoming smaller and smaller. Strain/stress concentrations are frequently localized in very tiny zones with high magnitudes. Determinations of thermal strain/stress and predictions of failure and reliability become more and more difficult. Recently, advanced optical techniques have been developed for electronic packaging analysis and have accomplished many tasks that could not be accomplished by conventional experimental methods. Optical techniques have been used for experimental stress/strain analysis, on-line inspections, simulation validations, and hybrid methods in many packaging areas. In this paper, recent developments in optical techniques are discussed. Several techniques are demonstrated by applications that are directly related to new electronic product development. The examples show the results and impact of using these optical techniques in the electronics industry to assist in product designs, qualifications, reliability improvements, and cycle time reductions.

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Martín, Francisco Ferrero, Marta Valledor Llopis, Juan C. Campo Rodríguez, Alberto López Martínez, Ana Soldado Cabezuelo, María T. Fernández-Arguelles, and José M. Costa-Fernández. "Optoelectronic Instrumentation and Measurement Strategies for Optical Chemical (Bio)Sensing." Applied Sciences 11, no. 17 (August 26, 2021): 7849. http://dx.doi.org/10.3390/app11177849.

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There is a growing interest in the development of sensitive, portable, and low-cost instrumentation for optical chemical (bio)sensing. Such instrumentation can allow real-time decision-making for industry, farmers, and researchers. The combination of optical fiber schemes, luminescence spectroscopy techniques, and new materials for sensor immobilization has allowed the growth of optical sensors. This article focuses on the development of low-cost optoelectronic instrumentation and measurement strategies for optical chemical (bio)sensing. Most of the articles in this field have focused on the chemical sensors themselves, although few have covered the design process for optoelectronic instrumentation. This article tries to fill this gap by presenting designs for real applications, as carried out by the authors. We also offer an introduction to the optical devices and optical measurement techniques used in this field to allow a full understanding of the applications.

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Deshpande, A. M., G. Subbarayan, and R. L. Mahajan. "Maximizing Solder Joint Reliability Through Optimal Shape Design." Journal of Electronic Packaging 119, no. 3 (September 1, 1997): 149–55. http://dx.doi.org/10.1115/1.2792227.

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The automated search techniques from the field of numerical optimization provide tools that enable optimal design of electronic packages in general, and solder joints in particular. However, there is considerable difficulty in using these procedures for solder joints since the estimation of fatigue life is computationally very expensive. In this paper, global approximation schemes based on designed experiments, linear regression models, and artificial neural network models are developed to approximate the fatigue life as a function of solder joint design parameters. Since these approximate surfaces are inexpensive to evaluate, their use with the numerical optimization techniques leads to a computationally efficient method for optimizing electronic packages. The developed techniques are demonstrated using the 225 I/O Plastic Ball Grid Array (PBGA) package, manufactured by Motorola, Inc. An exact optimization of the solder joints (without approximations) is also carried out and used as a basis for comparing the accuracy and efficiency of the developed methods.

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Kushwaha, Pragya, Avirup Dasgupta, Ming-Yen Kao, Harshit Agarwal, Sayeef Salahuddin, and Chenming Hu. "Design Optimization Techniques in Nanosheet Transistor for RF Applications." IEEE Transactions on Electron Devices 67, no. 10 (October 2020): 4515–20. http://dx.doi.org/10.1109/ted.2020.3019022.

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Liuzzi, G., S. Lucidi, F. Parasiliti, and M. Villani. "Multiobjective optimization techniques for the design of induction motors." IEEE Transactions on Magnetics 39, no. 3 (May 2003): 1261–64. http://dx.doi.org/10.1109/tmag.2003.810193.

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Chang, Jun, Zhi Cheng Weng, Yong Tian Wang, De Wen Cheng, and Hui Lin Jiang. "Optical System Design with High Resolution and Large Field of View for the Remote Sensor." Key Engineering Materials 364-366 (December 2007): 550–54. http://dx.doi.org/10.4028/www.scientific.net/kem.364-366.550.

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In this paper, we are presenting a design method and its results for a space optical system with high resolution and wide field of view. This optical system can be used both in infrared and visible configurations. The designing of this system is based on an on-axis three-mirror anastigmatic (TMA) system. Here the on-axis concept allows wide field of view (FOV) enabling a diversity of designs available for the Multi-Object Spectrometer instruments optimized for low scattered and low emissive light. The available FOVs are upto 1º in both spectrum ranges, whereas the available aperture range is F/15 - F/10. The final optical system is a three-mirror telescope with two on-axis and one off-axis segment and its resolution is 0.3m or even lower. The distinguished feature of this design is that it maintains diffraction-limited image at wide wavelengths. The technological developments in the field of computer generated shaping of large-sized optical surface details with diffraction-limited imagery have opened new avenues towards the designing techniques. Such techniques permit us to expand these technological opportunities to fabricate the aspherical off-axis mirrors for a complex configuration.

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Wijanto, Eddy, and Chun-Ming Huang. "Design of Bipolar Optical Code-Division Multiple-Access Techniques Using Phase Modulator for Polarization Coding in Wireless Optical Communication." Applied Sciences 11, no. 13 (June 26, 2021): 5955. http://dx.doi.org/10.3390/app11135955.

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In this study, a bipolar optical code-division multiple-access (Bi-OCDMA) technique based on spectral amplitude coding (SAC) was proposed by using a phase modulator to realize polarization coding through a free-space optical (FSO) channel. Various types of noise, such as amplified spontaneous emission (ASE) noise, thermal noise, and shot noise, were included in the simulation to approach the real application. The first simulation, utilizing a modified M-sequence as signature code, demonstrated that the proposed Bi-OCDMA system could be implemented in FSO communication. The proposed Bi-OCDMA scheme improves the transmission rate and power efficiency compared with the previous scheme. The structure of the proposed system alleviates multiple-access interference (MAI) with a simple and cost-effective design. The second simulation observed the performance of the proposed Bi-OCDMA for two users with several well-known SAC codes, i.e., multi-diagonal (MD) code, modified quadratic congruence (MQC) code, modified maximum length sequence (M-sequence) code, and Walsh–Hadamard code, in extreme weather conditions, both for additive white Gaussian noise (AWGN) and turbulence-induced fading channel. The simulation results indicated that the Walsh–Hadamard code has superior performance compared to other codes. The results show the MD code can be implemented in the proposed Bi-OCDMA scheme for a medium-distance FSO.

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Radványi, András G., László Gáspár, and Géza Tóth. "CNNUM stereo architecture and 3D template design techniques." International Journal of Circuit Theory and Applications 27, no. 1 (January 1999): 25–41. http://dx.doi.org/10.1002/(sici)1097-007x(199901/02)27:1<25::aid-cta39>3.0.co;2-v.

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Poad, Farhana Ahmad, Noor Shuraya Othman, Roshayati Yahya Atan, Jusrorizal Fadly Jusoh, and Mumtaz Anwar Hussin. "Automated detection of vehicles license plate using image processing techniques." Indonesian Journal of Electrical Engineering and Computer Science 18, no. 3 (June 1, 2020): 1408. http://dx.doi.org/10.11591/ijeecs.v18.i3.pp1408-1415.

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The aim of this project is to design an Automated Detection of License Plate (ADLP) system based on image processing techniques. There are two techniques that are commonly used in detecting the target, which are the Optical Character Recognition (OCR) and the split and merge segmentation. Basically, the OCR technique performs the operation using individual character of the license plate with alphanumeri characteristic. While, the split and merge segmentation technique split the image of captured plate into a region of interest. These two techniques are utilized and implemented using MATLAB software and the performance of detection is tested on the image and a comparison is done between both techniques. The results show that both techniques can perform well for license plate with some error.

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Malik, Deepak, Geeta Kaushik, and Amit Wason. "Performance Optimization of Optical Amplifiers for High Speed Multilink Optical Networks using Different Modulation Techniques." Journal of Optical Communications 40, no. 4 (October 25, 2019): 333–40. http://dx.doi.org/10.1515/joc-2017-0090.

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Abstract Next generation optical networks require large capacity communication networks for proper utilization of gain bandwidth of the networks. Optical amplifiers with wavelength division multiplexed (WDM) systems are the key technologies for the realization of these networks. In this paper, we have investigated the performance of the networks using different modulation techniques, such as return-to-zero (RZ), non-return-to-zero (NRZ) and duobinary. Attempts were taken to design 8 channels, 10 Gbps WDM network at channel spacing of 0.8 nm. An innovative model with EDFA-Raman amplifier is designed to examine the performance of the different modulation schemes. From the results, it is found that NRZ configuration gives maximum output power and good quality of communication as compared to other modulation schemes. Further, it is seen that with increase in channel dispersion from 2 to 4 ps/nm/km, the quality of the signal started decreasing.

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Journal articles on the topic 'Optical design techniques'

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