Dissertations / Theses on the topic 'Optical attenuators'
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Dudus´, Anna. "Optofluidics based fibre-optic variable optical attenuators." Thesis, University of Strathclyde, 2015. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=24985.
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An important research topic in engineering and science is the miniaturization of systems and components, where small size and weight, low power consumption and low manufacturing cost can offer new functionalities. In recent years the fields of optics and fluidics have merged to create the area of research known as "optofluidics". The unique properties of fluids (compression, flow, and variable refractive index) can be combined with optical devices to create systems with advantages in optical measuring, communication and imaging areas. Variable optical attenuators (VOAs) are components in optical communication networks for managing optical power levels. This thesis is focused on the design, fabrication and characterization of two novel optofluidics based single-mode fibre VOAs ("continuous fibre" type VOA and "fibre gap" type VOA). The first VOA is constructed from a side-polished optical fibre which is characterized by a sloping shape profile of the external cladding thickness. The fibre is positioned on top of a platform which exploits electrowetting-on-dielectric (EWOD) techniques to move a liquid droplet. By moving a liquid droplet across EWOD platform (and along the polished region of the fibre), optical attenuation can be obtained. The droplet, whose refractive index is equal to or higher than the refractive index of the fibre core, is accessing and leaking radiation from the optical evanescent field of the polished fibre which then modifies the optical attenuation. The level of attenuation depends on the position of the droplet; the attenuation increases as the cladding thickness reduces and the droplet moves closer to the fibre core. The second VOA is a fibre gap device, where a ferrofluid shutter/actuator is located in the gap between lensed single mode optical fibres. The ferrofluid shutter movement is controlled by a magnetic field and changes the light propagation between fibres. The level of attenuation is defined by the shutter position.
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Gagnon, Guy. "Thermo-optic variable optical attenuators using plasmon-polariton waveguides." Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/26639.
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A plasmon-polariton waveguide is investigated for its thermo-optic capability for the first time in the context of variable optical attenuators. The optical waveguide's metal core embedded into thermo-optic materials can be heated due to ohmic losses when current is injected through it. Hence, the optical and electrical function is agglomerated into the same waveguide layer. Heat changes the surrounding materials' refractive index and affects light propagation. The variable optical attenuator's response time was shown to be as fast as 50mus. The 8mum x 20nm metal waveguide achieves 19dB extinction ratio with 222 mW of electrical power consumption. Many other waveguide's characteristics were obtained experimentally and through thermal, electrical and optical modeling.
The metal waveguide was used as a non-invasive, direct and accurate temperature sensor. Electromigration and electrostatic discharge were investigated as the waveguide's degrading mechanisms. A novel optical method to study thin metal films' degradation due to electromigration is suggested.
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Tomljenovic-Hanic, Snjezana, and snjezana@physics usyd edu au. "Propagation effects in optical waveguides, fibres and devices." The Australian National University. Research School of Physical Sciences and Engineering, 2003. http://thesis.anu.edu.au./public/adt-ANU20040921.104741.
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This thesis consist of a theoretical study of propagation effects in optical waveguides, fibres and photonic crystals, with some comparison with experiment.¶
Chapter 1 gives a brief introduction with the current view of optical components in photonic integrated circuits and issues related to the loss mechanism.¶
In Chapter 2 the characteristics of single-mode propagation and transient effects in practical square- and rectangular-core buried channel planar waveguides are quantified, assuming a cladding which is unbounded in one transverse dimension and bounded in the other. The wavelength cut-off condition for the fundamental mode is determined when the cladding index is asymmetric and composed of step-wise, uniform index regions.¶
In Chapter 3, the application of segmented reflection gratings in planar devices that can function as either a single- or two-wavelength add/drop filter is investigated and a numerical technique developed in Chapter 2 is applied to the waveguides with high extinction ratio. The role of the segmented gratings is analogous to that of a blazed grating, but they can provide a higher reflectivity level at the Bragg wavelength, eliminate back reflection into the fundamental mode and provide arbitrarily small channel spacing in the two-wavelength case.¶
Chapters 4 address the problem of bend loss in a single-mode slab waveguide. A new theoretical strategy for reducing bend loss is presented and compared to existing designs. The results obtained in this chapter are the basis for the following two chapters.¶
Chapter 5 deals with bend loss in single-mode buried channel waveguides and demonstrates that the new strategy can lead to significant bend loss reduction when compared to other strategies, and, conversely, can be used to enhance bend loss for a fixed bend radius for application to devices such as optical attenuators.¶
In Chapter 6, a novel design of a variable optical attenuator based on a bent channel waveguide is proposed, realized by applying a new strategy for bend loss control in a polymer buried channel waveguide.¶
Chapter 7 investigates effects of the additional rings in a single mode step-index fibre on bend loss. It is supported with the experimental results of Ron Bailey from Optical the Fibre Technology Centre, University in Sydney.¶
In Chapter 8, bend loss of a one-dimensional photonic crystal is quantified and compared to bend loss of a standard single-mode slab waveguide and a bend-resistant waveguide.¶
4
Ghauri, Farzan Naseer. "Hybrid Photonic Signal Processing." Doctoral diss., University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3233.
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This thesis proposes research of novel hybrid photonic signal processing systems in the areas of optical communications, test and measurement, RF signal processing and extreme environment optical sensors. It will be shown that use of innovative hybrid techniques allows design of photonic signal processing systems with superior performance parameters and enhanced capabilities. These applications can be divided into domains of analog-digital hybrid signal processing applications and free-space--fiber-coupled hybrid optical sensors. The analog-digital hybrid signal processing applications include a high-performance analog-digital hybrid MEMS variable optical attenuator that can simultaneously provide high dynamic range as well as high resolution attenuation controls; an analog-digital hybrid MEMS beam profiler that allows high-power watt-level laser beam profiling and also provides both submicron-level high resolution and wide area profiling coverage; and all optical transversal RF filters that operate on the principle of broadband optical spectral control using MEMS and/or Acousto-Optic tunable Filters (AOTF) devices which can provide continuous, digital or hybrid signal time delay and weight selection. The hybrid optical sensors presented in the thesis are extreme environment pressure sensors and dual temperature-pressure sensors. The sensors employ hybrid free-space and fiber-coupled techniques for remotely monitoring a system under simultaneous extremely high temperatures and pressures.Ph.D.
Optics and Photonics
Optics and Photonics
Optics PhD
5
Tian, Zhaobing. "In-line optical fiber interferometric refractive index sensors." Thesis, Kingston, Ont. : [s.n.], 2008. http://hdl.handle.net/1974/1358.
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Huang, Zhengyu. "Novel Segment Deformable Mirror Based Adaptive Attenuator Used In Wavelength Division Multiplexed Optical Communications Network." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/34454.
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In wavelength division multiplexed (WDM) optical communication networks, signals are amplified periodically by optical amplifiers. Since the gain profiles of optical amplifiers are not flat, equalizers are usually used to maintain signal powers at different wavelengths in equal to avoid crosstalk and data loss. However, fixed attenuation can only compensate fixed input power and amplification. In active network, input power and amplifier gain change with time. Active level compensation at each wavelength is needed. An adaptive attenuator is a device with a chromatically variable transmissivity used to equalize channel powers in wavelength-division multiplexing (WDM) fiber-optic communication lines. In this thesis, a method of Fourier analysis of multi-beam interference is developed. It is shown that the total electric field and relative phase delay of each beam form a Fourier transform pair. Thus methods and properties of Fourier analysis are applicable in multi-beam interference analysis and design. Fourier transform based design is presented. Novel devices that apply such design principles are introduced. Principles and structures of novel adaptive attenuators based on various technologies such as segment deformable mirror, liquid crystal, phase modulation array are given. Simulation results for segment deformable mirror based adaptive attenuator are presented.Master of Science
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Šustr, Pavel. "Optický zesilovač v laboratorní výuce." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218165.
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The aim of this thesis is to introduce to reader the application and use of optical EDFA amplifiers in optical transmission and to show wiring and practical test, including measurements on amplifier. The aim of this thesis is to propose the use of optical amplifier in laboratory practice for subject Optical networks. The thesis briefly introduces the problems of data transmissions through optical fibers with a focus on the use of optical amplifiers. The basic characteristic of optical transmission paths and the reasons for the use of optical amplifiers are described here. One entire chapter is devoted to distinction of optical amplifiers. Amplifiers can be divided according to location in the transmission path to the booster, in-line and pre-amplifiers and according to the used of amplifying technology to optical amplifiers with subsidies, semiconductor optical amplifiers and Raman optical amplifiers. The factors affecting the efficiency of optical amplifiers, such as noise and the level of saturated power are mentioned here too. The different types of optical amplifiers from the two producers are also described. From these amplifiers was chosen EDFA CzechLight Amplifier from Optokon to be used for the laboratory exercise in the subject of Optical networks. The use of EDFA optical amplifiers in optical transmission lines is mentioned here too. These amplifiers can be used in telecommunications transmission systems and for data transmission over long distances. They will find use in WDM transmission systems and cable TV distribution through the optical fiber to the end users. Practical measurements were performed on optical amplifier CLA-PB01F. In the transmission route was located attenuator and the dependence of output power to input signal power was measured. The amplification course was linear in the range of input values provided by the manufacturer. Laboratory exercise for the subject of Optical networks is aimed at preacquaintance of students with problems EDFA optical amplifiers and practical measurements with the optical amplifier CLA-PB01F. Students acquire basic theoretical knowledge of the issue and verify the functionality of optical amplifiers on a specific exercise. This work is destined for all who wish to get basic knowledge of optical amplifiers, their characteristics and possibilities of their use in optical transmission lines.
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Haidar, Jihad. "Commande optoélectronique d'atténuateurs, de résonateurs et de filtres microondes réalises sur substrat silicium." Grenoble INPG, 1996. http://www.theses.fr/1996INPG0094.
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La commande optique de dispositifs microondes, qui exploite l'injection optique des porteurs dans un semiconducteur, apporte de nombreux avantages vis-a-vis de l'electronique conventionnelle. La presente etude avait pour objectif d'etendre cette commande a des dispositifs, realisant des fonctions complexes, tels que les attenuateurs, resonateurs et filtres microondes. Les structures etudiees ont ete realisees sur du silicium en technologie ligne microruban. Nous avons exploite principalement la charge complexe induite entre le ruban et le plan de masse par illumination optique. Nous avons demontre que la lumiere cree principalement une charge resistive aux faibles puissances, mais qu'une composante reactive apparait aussi d'une maniere nette pour les puissances optiques elevees. L'effet resistif a ete mis en application dans la realisation d'un attenuateur microondes en technologie microruban, reglable par la simple commande optique. Nous avons demontre sur un premier prototype une plage d'attenuation superieure a 10db dans la bande c. Quant a l'effet reactif, nous avons introduit une commande supplementaire qui permet de le renforcer. Il s'agit de polariser le plasma photo-induit par une tension continue qui se superpose au signal hyperfrequences. Nous avons accorde la frequence de differents resonateurs par cette nouvelle double commande optoelectronique. Ces accords, sont, a notre connaissance, de loin les plus larges jamais reportes parmi les accords electriques. En effet, nous avons mesure des deplacements de la frequence de resonance de l'ordre de 30% en dessous de la frequence de resonance en l'absence d'illumination. L'etude est plutot de nature experimentale, mais des modeles theoriques simples ont ete developpes pour tenter d'expliquer les differents phenomenes nouveaux mis en evidence experimentalement. Nous avons reussi a etablir, d'une maniere satisfaisante en premiere approche, le lien entre les parametres physiques du semiconducteur d'une part et le schema equivalent du plasma photo-induit deduit de la reponse microondes du dispositif d'autre part
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賴宜君. "Investigation and applications of variable optical attenuators." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/33718980086660537501.
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碩士國立臺灣科技大學
電子工程系
92
In this thesis, we investigate the fabrication of the variable optical attenuators (VOAs). The major technique that we used is the Micro-Electro-Mechanical-System (MEMS), which may find many potential applications because of the characteristics of light weight, small size, low power consumption, and novel structure. The VOA devices are built in a silicon-based structure with only step of mask process is necessary. We design three types of VOAs, the concepts of them are by moving back and forth of the mirror, by rotating the angle between mirror with optical fiber, and misalignment the two section of fiber cores. We use the Inductively Coupled Plasma-Reactive Ion Etching (ICP-RIE) to fabricate micro mirrors, micro actuators and U-grooves on the silicon substrate. Then the micro actuator is droved by electrostatic method. The driving voltage, insertion loss and the dynamic range of home-made VOAs are 12.5-60 volt, 8dB and 12 dB, respectively. Beside investigation of VOA with MEMS technology, another three kinds of methods are proposed to fabricate VOAs. They are based on the concept of fiber bending loss and precisely fiber cores alignment. For the firs kind VOA, its dynamic range is as high as 35dB. And it insertion loss is less than 1.0 dB thank to the all fiber based construction. However, it has the drawback power fluctuation due to fiber bending. Nevertheless, neither polarization mode dispersion (PMD) nor polarization dependent loss (PDL) is observed. For the design of machine-based VOA, which includes a mirror, a shutter and a pair of collimated fibers. The optical power may attenuate partly or entirely by moving the shutter and result to power attenuation. Its dynamic range is 58dB with merits of good reliability and high resolution.
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Tomljenovic-Hanic, Snjezana. "Propagation effects in optical waveguides, fibres and devices." Phd thesis, 2003. http://hdl.handle.net/1885/48210.
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Yang, I.-Chen, and 楊怡箴. "A Novel Variable Optical Attenuator for Fiber Optical Communication." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/88139217008533645731.
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碩士國立中山大學
光電工程研究所
90
A novel variable optical attenuator based on buried polymer waveguides and waveguide bends is proposed. The attenuator consists of three waveguide sections, separated for waveguide bending by two embedded micorprisms. The attenuation of device was achieved by steering the beam propagation direction in the waveguide by thermo-optical effects. Detailed simulation results using the Beam Propagation Method are presented. In addition, radiation losses of the waveguide bends are experimentally investigated. After two-10° bends, the normalized insertion losses as low as 65.7％ are obtained. The propagation loss of the buried waveguide is 0.47dB/cm at l=1.3 mm.
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林正軒. "Micro Bimorph Thermal Actuators and Application in Optical Attenuator." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/69108617906768442875.
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Wang, Hseng-Tsong, and 王勝聰. "Design and Fabrication of Polymer Waveguide Variable Optical Attenuator." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/52716250641462921278.
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碩士國立交通大學
光電工程所
91
Polymer with low propagation loss, high glass transition temperature(Tg), and high thermooptic coefficient have been used worldwide for photonic components. In this paper, a polymer thermooptic waveguide type variable optical attenuator is proposed. The S-shape buried waveguide structure with polymer core and silica cladding that attenuates light with satisfactory optical attenuation through the spectrum from 1.52mm to 1.57mm is presented. The waveguide bend design is compatible with photolithography fabrication techniques and operates by controlling waveguide bend radiation loss. For a 4850mm bend length, optical attenuation of 30dB has been achieved after we carry out that device. In addition, this design is suitable to integrate with planar lightwave devices to fabricate the monolithic optical modules in application of optical communication.
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Pan, Shu-wen, and 盤舒文. "FPGA Design to an Variable Optical Attenuator Control Circuit." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/19448246104460776276.
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碩士雲林科技大學
通訊工程研究所碩士班
97
The dissertation uses the FPGA (Field Programmable Gate Array) to replace the 8051 (single-chip microprocessor) in the VOA (Variable Optical Attenuator) applications. In the whole system, the analog circuit includes the O/E (optical to electro) conversion, the ADC (Analog to Digital Converter), the DAC (Digital to Analog Converter), the VOA driver, and rectifier circuits, and the digital circuits are designed on FPGA development board: the Max II Starter Kit and use the ALTERA Quartus Ⅱ 7.0 software to design, simulation, and burn. The digital circuits is divided into the input/compare circuit, the fine tune circuit, the default output value select circuit, the output buffer circuit, and the system clock generator circuit. In the system, the sampling rate is 512 kHz. When only use the fine tune circuit, the attenuation rates are changed from 3 dB to 10 dB and from 10 dB to 3 dB the transition times are 2.25 ms and 2.4 ms, respectively. When the default output value select circuit is used, the attenuation rates are changed from 3 dB to 10 dB and from 10 dB to 3 dB the transition times are 0.65 ms and 0.95 ms, respectively. The default output value select circuit can effectively reduce the transition times. When the default output value select circuit is used, too, the attenuation rates are changed from 0 dB to 19.87 dB（attenuation rate is 97）and 19.87 dB and 0 dB, the transition times are 0.5 ms and 0.76 ms, respectively, when un-use and use the default output value select circuit, respectively. The transition times are similar to the attenuation rates are changed from 3 dB to 10 dB and from 10 dB to 3 dB. Therefore, the transition times are independent on the changing of the attenuation rates when use the default output value select circuit.
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Yu-Wei, Yeh. "The MEMS Organic Thin Film For Variable Optical Attenuator Applications." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2507200614020400.
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Yeh, Yu-Wei, and 葉裕偉. "The MEMS Organic Thin Film For Variable Optical Attenuator Applications." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/79273189562665629028.
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碩士國立臺灣大學
光電工程學研究所
94
The variable optical attenuator is a critical optical component in WDM fiber-optic communication system. It can be used to equalize the optical gain, block the optical signal, and prevent the saturation of the receiver. In this thesis, we design a novel reflection type variable optical attenuator. It not only includes the characteristic of low PDL, but also can be easily fabricated compared to the common reflection type VOA. The VOA is made by an optical fiber collimator and a deformable mirror. Due to the defocus effect, the optical power could be adjusted by controlling the curvature of the deformable mirror. According to the material selection chart, the low stress organic material is applied to compose the deformable mirror. By micromachining fabrication, the 6 mm X 6 mm deformable mirror was successfully fabricated and tested without crack. The residual stress and Young’s modulus are measured as low as 3.5 Mpa and 15 Gpa, respectively. Due to these mechanical properties of organic thin films, the curvature of the deformable mirror as large as 20 mm is achieved by pneumatic force. The 8 dB optical attenuation is experimentally measured and agreed well with theoretical simulation. The PDL and WDL are both as low as expectation because of the center symmetric optical design. As a result, the novel MEMS VOA has been successfully designed, fabricated, and tested.
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江學士. "A 5V MEMS Variable Optical Attenuator using Rotary Comb Drive." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/56504690026931271668.
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碩士國立清華大學
微機電工程研究所
93
Variable Optical Attenuator (VOA) applied to control the optical signal intensity is an important device for the transceiver/receiver in optical communication system. In this thesis, a low voltage, no overshoot and anti-impact MEMS VOA would be implemented by MEMS technologies. Rotary comb drive was chosen as the actuator of VOA to prevent impact because its rigidity in rotation direction was much smallr than that in XYZ directions. However, rotary comb drive had high driving voltage. Serpentine spring with low spring constant could help to reduce the driving voltage. Considering the equivalent of mechanical and electrostatic torques, the device parameters were designed to achieve 20 rotation in 5V. Four optical attenuations (cantilever-type, pendulum, tilted, and folded micromirrors) were also devised to have maximum attenuation >40dB in 20 rotation by using TracePro simulation tool. Mask layout and fabrication followed the device design. SOI micromachining developed the device main structure. Then Au sputter process made the micromirror reflection. Finally, we measured the deices after fabrication completed. In this thesis, the design, fabrication, and measurement were accomplished. The MEMS VOA implemented could operate in 5V and have 400Hz bandwidth. Its step response showed no overshoot. The Tilted Micromirror design attenuated to maximum 55dB. The optical dynamic response <3ms, insertion loss=0.95dB, PDL=0.3dB, and WDL (1510~1590nm)=0.87dB.
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Chen, Yu-Da, and 陳煜達. "Application of Ionic Polymer Metallic Composite in Variable Optical Attenuator." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/93419462193240192368.
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碩士國立臺灣大學
光電工程學研究所
99
Ionic-polymer-metallic composite (IPMC) can be actuated by low voltage and be bended gradually with increasing driving voltage. We used IPMC as a variable optical attenuator (VOA) in free space configuration. We measured the insertion loss, optical attenuation range, polarization dependent loss (PDL), wavelength dependent loss (WDL), and response time. We concluded that our IPMC can be actuated by less than two volts. The surface roughness of our IPMC was about 0.66 μm and the insertion loss was 2.89 dB, and optical attenuation range of our device is as great as 80 dB with 40 dB/volt resolution. The range of PDL is about from 0.1 dB to 0.6 dB. The wavelength dependent loss is from 0.15 dB to 0.85 dB in the wavelength range from 1527 nm to 1563 nm. Response time and relaxation time of the device are about 0.5 second and 0.3 second. The actuation voltage was 2 volts and the power consumption was 5.78 mW.
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Tsai, Julius M., and 蔡明霖. "Fabrication and Design of variable optical attenuator utilizing <111> wafer." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/97110328790591988277.
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博士國立清華大學
動力機械工程學系
92
Ever since the invention of telegram and telephone, human beings for the first time have the ability to communicate with each other with the speed of light. Even further, the invention of fiber keeps pushing the communication from not just speed but also to quantity and quality. Although the fiber has advantages such as large bandwidth, low loss, low cost, lightweight, high integrity, anti-corrosion, information security and immunity to EM disturbance, the real capacity of fiber has never been reached due to the lack of efficient devices to manipulate light. In real optical network the mechanical components have been used on switching or attenuating light signals for a long time. But those traditional mechanical components are heavy and response slowly compared to the demands of modern desires. Therefore it is imperative to develop efficient devices for that purpose, and MEMS seems to point out a way. In this research, a novel variable optical attenuator has been proposed for further studies. In this article, we have done literature surveys for all kinds of methodologies to attenuate light signals. And we concluded shutter-based MEMS VOA has the benefits of high speed, low power, large dynamic range and low polarization loss. By using shutter-based method, a novel VOA has been proposed with detailed mechanical and optical characteristic simulations including mechanical/optical static response and insertion loss of fiber positions and shutter positions. The device is fabricated with the BELST II process and detailed description of the process is recorded. Finally the novel VOA is characterized with mechanical static measurement, mechanical dynamic measurement, fatigue test, insertion loss, optical dynamic range and back reflection loss.
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Chang, Jer-Wei, and 張哲瑋. "A Micro TM-Mode Variable Optical Attenuator for Planar Lightwave Circuit applications." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/63826228939765930630.
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碩士國立清華大學
動力機械工程學系
96
In optical transmission systems, variable optical attenuators (VOAs) are fundamental components. They play important roles in equalizing channel intensity levels in Dense Wavelength Division Multiplexing (DWDM) systems and flattening the gain spectrum of optical amplifiers. Variable optical attenuators based on planar lightwave circuits (PLCs) are attractive in the ability to integrate with other optical devices. A novel structure of a variable optical attenuator is proposed in this thesis. The configuration of the VOA includes a fiber groove that the single mode fiber and Grin fiber will be placed, an output waveguide, and a driven mirror with a flexible spring to fix it. The V-shape thermal actuator is designed to drive the mirror. We utilize the incident angle changes between two medium under the TM polarization to manipulate the optical power. Mask layouts and fabrications follow the device design. We use SOI (silicon -on-insulator) wafers to manufacture the VOAs by Micro-Electro-Mechanical Systems (MEMS) technology and then measure them finally.
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Li, Chao-Hu, and 李朝湖. "Variable Optical Attenuator Made of Deformable Mirror Based on Micro-Electro-Mechanical System Technology." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/32316190366558174745.
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碩士國立臺灣大學
光電工程學研究所
96
An optical attenuator is one of the important components in optical communication system to control an optical signal transmission. It provides a variety of functions, such as power tuning of laser, dynamic gain controlling and equalizing of different channels in WDM system, and overload protection of optical device. In this thesis, we demonstrate a novel MEMS VOA made of polyimide thin film actuated by electrostatic force. We started with simulating the optical system by wave optics and constructed a model in optical system design software, ZEMAXTM. After, we fabricate a deformable mirror by micro-electro-mechanical system technology to serve as the main structure of the VOA. We assemble the deformable mirror to a bottom electrode by thermal bonging to form a DM-VOA. We measured the maximum optical attenuation is 30.8dB caused by the DM-VOA with 188V applied. The polarization dependent loss is very low due to geometric symmetric structure of the mirror, as simulated. The power consumption of the driving circuit is also measured, which is around 153mW. Therefore, we think the DM-VOA is a good potential for long-haul optical communication system using from these measured properties.
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Li, Chao-Hu. "Variable Optical Attenuator Made of Deformable Mirror Based on Micro-Electro-Mechanical System Technology." 2008. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-0508200811260400.
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