Dissertations / Theses on the topic 'OPO Fibre'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 15 dissertations / theses for your research on the topic 'OPO Fibre.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Ghawas, Muhammad. "Sources picosecondes et femtosecondes à base de fibre dopées Ytterbium et applications." Electronic Thesis or Diss., Bordeaux, 2023. http://www.theses.fr/2023BORD0463.
Ultrashort laser pulses in both industrial and research applications progressively rely on fiber laser technology, guided by its intrinsic benefits, for instance, stability, compact nature, excellent beam quality, robustness, and easy operation. In this work, a detailed study has been done to investigate picosecond fiber laser working in an all-normal-dispersion (ANDi) regime for the application of parametric generation in photonic crystal fiber. In summary, we have developed a high-power fiber laser source delivering picosecond pulses with tunability both in central wavelength and spectral width. It incorporates a combination of a large-mode-area rod-type ytterbium fiber, a slit, and a transmission grating inside the ring laser cavity configuration. At the central wavelength of ∼ 1030 nm and with a repetition of 78 MHz, this laser delivers picosecond pulses with an average power of up to 25 W. The pulse duration can be continuously adjusted from ∼ 1.8 ps to ∼ 4.5 ps and pulse energy from ∼ 320 nJ and ∼ 225 nJ, respectively. Additionally, we have also demonstrated that the central wavelength of the laser pulse can be finely tuned from ∼ 1010 nm to ∼ 1060 nm while keeping the pulse energy above ∼ 150 nJ. We have also proposed a numerical model to account for the ensemble of our experimental data and the simulations are in good agreement with the experimental data. The output of this fiber oscillator is propagated through the photonic crystal fiber for the parametric generation of the signal (higher frequencies than the pump) and idler (lower frequencies than the pump). The fiber OPO singly-resonant cavity was built in such a way that only signal wavelengths are allowed to propagate through it. The conversion efficiency for the signal was close to 20 % in the fiber OPO. Based on the dispersion profile of the photonic crystal fiber and our homebuilt tunable pump laser, the signal wavelength (resp. idler) was tuned from ∼ 770 nm to ∼ 1000 nm (∼ 1130 nm to ∼ 1590nm) for the corresponding pump wavelengths of ∼ 1024 nm to ∼ 1059 nm
Brieussel, Alexandre. "Mini squeezers towards integrated systems." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066104/document.
Squeezed states of light are quantum states that can be used in numerous protocols for quantum computation and quantum communication. Their generation in labora- tories has been investigated before, but they still lack compactness and practicality to easily integrate them into larger experiments. This thesis considers two experiments: one conducted in France, the miniOPO; and one conducted in Australia, the SquOPO. Both are new designs of compact sources of squeezed states of light towards an integrated system. The miniOPO is a linear cavity of 5mm length between the end of a fiber and a curved mirror with a PPKTP crystal of 1mm inside it. The squeezing generated in this cavity is coupled into the fiber to be able to be brought to a measurement device (homodyne) or to a larger experiment. The cavity is resonant for the squeezed light and the pump light, and locked in frequency using self-locking effects due to absorption of the pump in the crystal. The double resonance is achieved by changing the temperature of the crystal. Two different fibers have been tested in this experiment, a standard single-mode fiber and a photonic large core single-mode fiber. The squeezing obtained is still quite low (0.5dB with the standard fiber and 0.9dB for the photonic fiber) but a number of ameliorations are investigated to increase these levels in the future. The SqOPO is a monolithic square cavity made in a Lithium Niobate crystal using four total internal reflections on the four faces of the square to define an optical mode for the squeezed mode and the pump mode. The light is coupled in the resonator using frustrated internal reflection with prisms. The distance between the prisms and the resonator defined the coupling of the light, which allows us to control the finesse of the light in the resonator and by using birefringent prisms it is possible to tune independently the two frequencies in the resonator to achieve an optimal regime. The frequency of the light is locked using absorption of the pump light in the resonator to achieve self-locking, and double resonance is controlled by tuning the temperature of the crystal. We demonstrated 2.6dB of vacuum squeezing with this system. Once again, the amount of squeezing is low, but ameliorations that could be implemented in the future are discussed
Le, Méhauté Simon. "Étude et réalisation d'un lidar dial cohérent fibré à 1.65 µm pour la mesure simultanée de la vitesse du vent et de la concentration de méthane." Thesis, Littoral, 2020. http://www.theses.fr/2020DUNK0555.
Especially in the oil and gas industry, methane leaks threaten both safety and environment. The real-time monitoring of such plumes could prevent potential human or ecological disasters. In this context, one part of NAOMI project, involving TOTAL and ONERA, aims to develop remote sensing tools capable of locating (with a spatial resolution of 100 m) and characterize major methane leaks from a safety distance (1 km) on the field. To meet these specifications, the present work describes the study, design and performances assessments of a fiber lidar emitting in the near infrared (1.65 µm) : VEGA ("VEnt et GAz", French for "wind and gaz"). The choice of a coherent detection scheme allows to consider a dual-function system, able to simultaneously measure wind speed with Doppler shift (useful to assess plume dynamic) and methane concentration with the DIAL technique. In the lab, integrated-path measurements (target at 2.2 km) have shown, a first to our knowledge with a coherent lidar, VEGA's sensibility to methane. The accuracy of ambient level measurements (1.95 ± 0.26 ppm for 1 s averaging) is seen to be satisfying for the target application (involving much higher concentration). During a field campaign in 2018 (Lacq, France), the lidar has shown a good thermo-mechanical behaviour, justifying the choice of an all-fibered architecture. The use of several measurement procedures (simple, several laser lines of sight, several wavelengths) allowed VAGA to identify controlled methane leaks at 200 m (30 m resolution) in a wide range of flow rates (from 0.1 to 300 g.s-¹. During the campaign, the observed statistical errors, in the ±10 to 100ppm range for 1 s averaging, are in good agreement with theoretical models. Assessing these errors at greater distances shows, nonetheless, a need to improve the lidar (through mentioned improvement tracks) to reach an adequate precision at 1 km. Eventually, the basis for autonomous flow rate estimation, combining both wind and gas data, had been presented
Rosolem, João Batista. "Amplificadores ópticos de dupla passagem incorporando fibras compensadoras de dispersão." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/18/18133/tde-31102005-125254/.
Double pass erbium doped fiber amplifiers (DP-EDFA) with an embedded dispersion compensation fiber are studied in this work. DP-EDFA is a cost-effective alternative for optical amplifiers, yet preserving good optical performance, mainly for use in metropolitan networks. Due to its double pass circuit, others functions beyond amplification can be inserted within the amplification circuit, increasing its capabilities and decreasing the involved cost. Considering that dispersion compensation is very critical for high-speed DWDM systems operating with standard single mode fiber, a timely topic of investigation concerns the embedding of the high insertion loss DCFs (dispersion compensating fibers) into optical amplifier configurations. Experimental studies are conducted first showing the advantages and impairments associated with DP-EDFAs circuits using DCFs. Next, a DP-EDFA proposed in this work is characterized in terms of gain and noise figure for several applications in multichannel and multiband network topologies. Systemic characterization in terms of bit error rate is also conducted, evaluating the performance of the proposed DP-EDFA using DCF
Amiard, Hudebine Gabriel. "Développement de sources lasers nanosecondes, picosecondes et femtosecondes et applications." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0024/document.
This two-part thesis focuses on the development of nano and picosecond laser sources and their applications. The first part presents the study, and the realization of a nanosecond laser amplifier chain for the ignition of turboshaft engines. After the repport of the performances and the evolution of this amplifier chain will be presented the results of the tests carried out on a combustion chamber on a test bench at ONERA under low temperatures and low pressures conditions. The second part of this thesis deals with the development of an optical parametric oscillator (OPO) in order to tune in the infrared the wavelength of a pulsed picosecond or femtosecond laser at high cadency and high average power. After presenting the OPO cavity and its performance, we will detail the ability of this OPO to generate compressed femtosecond pulses from pump chirped pulses
Michel, David Daniel. "Linear-cavity tunable fibre lasers employing an Opto-VLSI processor and a MEMS-based device." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2012. https://ro.ecu.edu.au/theses/520.
Bouyge, David. "Systèmes lasers impulsionnels compacts et dispositifs hyperfréquences accordables basés sur l'intégration de composants MEMS." Limoges, 2007. https://aurore.unilim.fr/theses/nxfile/default/ac1d8e2a-01a5-4522-a2a7-f571790878dc/blobholder:0/2007LIMO4054.pdf.
In spite of the large interest provoked by the integration of Micro-Opto-Electro-Mechanical-System (MOEMS) in optic systems, not enough experimentation concerning their capacity to produce short optic impulsions is developed. It is therefore in this direction that we orientated our jobs. First, this manuscript raises the state of art on MOEMS micro-mirrors and then introduces various kinds of pulsed laser systems regimes. The development of MOEMS is displayed across stages of conception, optimization of technology and characterization. We demonstrate a simple technique to produce active Q-switching in various types of fiber amplifiers by active integration MOEMS. We present the realization of a multiwavelength laser system which exploits the achromaticity of micro-mirrors for the generation of tunable radiations in the visible spectre. Finally, we study the development of tunable multipole reject band filters
Audo, Frédéric. "Opto-alimentation et transmission de données par fibre optique pour les observatoires de fond de mer." Phd thesis, Université de Bretagne occidentale - Brest, 2012. http://tel.archives-ouvertes.fr/tel-00782502.
Weeda, Jocelyn R. "Cultivating the Fire With(In): Teacher's Resistance in an Age of Corporate Reform." Miami University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=miami1407193226.
Hallak, Elwan Hamza. "Systèmes optiques dédiés à la 5° génération de réseaux sans fils (5G)." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAT047/document.
This thesis is for the development of future devices, systems and networks supporting the 5th Generation (5G) high-speed wireless internet. The demand for very high bit rate requires a sufficient large bandwidth, and therefore Millimeter-Wave (mm-wave) frequency band has a lot of interest. Several number of technologies will need to converge, co-exist and interoperate, and most importantly, cooperate, if this vision is to be efficiently and cost-effectively realized. The main concept within this next 5G is the integration of optical fiber networks and radio networks through Radio-over-Fiber (RoF) technology at mm-wave frequencies, to provide high-bandwidth front/backhaul services and enable scalable and manageable networks without a highly complex interface structure and multiple overlaid protocols.In this thesis, the mm-wave RoF communication systems are theoretically studied and experimentally demonstrated to investigate the system impairments. The work presented in this thesis is focused on optical noise represented by phase and intensity noise induced by optical source and chromatic dispersion introduced by optical fiber. The optical noise is analyzed and measured for different optical generation techniques. Two different down-conversion stages, mixer and envelope detector, are applied for signal processing and to decorrelate phase and intensity noise. We would like to highlight that this study and the model can be applicable toany kind of optical heterodyne generation system and any frequency range. The correlation among optical modes in optical frequency comb is examined to show the impact of chromatic dispersion. This thesis also exhibits the mm-wave power distribution over fiber span and how the chromatic dispersion effect on the RoF network is modified by varying dispersion parameters. Then, this thesis demonstrates how the optical phase decorrelation induced by chromatic dispersion results in mode partition noise at mm-wave RoF communication networks.When transmitting some types of data over the system, the results demonstrate the impact of optical noise and chromatic dispersion on the signal quality. The simulation results are presented and are in very good agreement with experimental results. The error vector magnitudethrough online process shows the impact of the system impairments on the system performance. The data rate and system evolution are compliance with communication standards at mm-wave
Maxin, Jérémy. "Oscillateurs optoélectroniques largement accordables et faible bruit pour les applications radar." Toulouse 3, 2014. http://thesesups.ups-tlse.fr/2727/.
The objectives of this thesis is the developement of two optoelectronic oscillator architectures dedicated to the generation of low noise microwave signals for radar applications. The first oscillator is based on the stabilization of the beatnote of a widely tunable dual-frequency laser with an optical fiber delay line. A fine analysis of the stabilization loop implemented with a 100 m long optical fiber allowed us to reach the technical limit fixed by the loop microwave amplifiers. The oscillator is tunable from 2. 5 to 5. 5 GHz by 2 MHz steps and present a phase noise power spectral density of -105 dBc/Hz at 10 kHz offset from the carrier (performance independent of the carrier frequency). The use of two optical fibers in a double delay lines architecture and of a fiber ring resonator as a delay line are also investigated. The second architecture developed is a coupled optoelectronic oscillator (COEO). The architecture, similar to a regenerative mode-locked laser, is realized by coupling a resonant laser cavity to a resonant optoelectronic loop. The developpement of this oscillator is based on a new architecture of SOA : an asymmetrical cladding semiconductor optical amplifier. This component offers better saturation power and lower intrinsic noise than the classical design. The COEO operates around 10 GHz. A phase noise power spectral density of -135 dBc/Hz is measured at 10 kHz offset from the carrier
Mustafa, Haithem A. "Opto-VLSI-based adaptive optical power splitter/combiner for next generation dynamic optical telecommunication networks." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2013. https://ro.ecu.edu.au/theses/923.
Lin, Shou-Tai, and 林碩泰. "Fiber-laser-pumped CW OPO for Mid-IR and RGB Laser Generation." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/00234526894355657603.
國立清華大學
光電工程研究所
97
利用週期性鋰酸鈮晶體建構一連續式、單波長光參數共振腔,進而產生一從可見光到中紅外光之可調雷射光源,為一個相當有效率的方法,其中的優點包含了高的轉換效率與極窄的輸出頻譜寬度。近來,由於連續式光纖雷射的迅速發展,其高輸出功率與近乎理想高斯分佈的空間特性,已經廣泛的被利用在光參數共振腔之幫浦光源上,這本論文發表了世界第一個,利用寬頻光纖雷射作為中紅外光參數共振腔的幫浦光源,並產生單頻之中紅外光源;同時,並利用光纖雷射幫浦一光參數共振腔,搭配腔內與腔外的波長轉換器,產生紅、藍、綠全彩雷射。 在此論文一開始,為了展現週期性鋰酸鈮晶體的多用途特性,我們先驗證了單一週期性鋰酸鈮晶體,可以同時當作波長轉換器與雷射Q值調變器,接著,我們利用一寬頻(1 nm)的1064 nm光纖幫浦雷射與一摻鎂週期性鋰酸鈮晶體為增益介質,得到了一連續式、單頻的中紅外雷射,在幫浦功率為25瓦與輸出波長為1.58與3.2 um時,我們得到輸出功率分別為5.3 與1.2瓦; 此外,藉由量測,超過瓦級之3.2 um光源為單頻輸出,同時其頻譜線寬為5 MHz。由於週期性鋰酸鈮晶體對於共振之中紅外波長有輕微的吸收行為,我們觀察到熱吸收引起的雙穩態與熱波導效應,當共振腔內功率達到熱波導閾質30瓦時,熱波導可以使光參數增益增加兩倍,由於幫浦雷射頻寬過寬,我們同時在幫浦雷射頻譜中觀察到燒洞現象。 波長可調的可見光雷射,可以藉由在紅外單波長光參數共振腔內串接兩級合頻產生器,將近紅外之幫浦雷射做頻率上轉換的方式來產生,我們將一寬頻的1064 nm光纖幫浦雷射光源轉換到可見光區域,並得到瓦級、連續式、紅、綠、藍全彩雷射,此近紅外單波長光參數共振腔之共振波長為1.56 um,並在共振腔內串接兩級合頻產生器得到紅、藍光,同時再利用一外部的倍頻器,將剩餘之幫浦雷射轉換到綠光,在25瓦幫浦功率時,我們得到4瓦的紅光(633 nm)、0.48瓦的綠光(532 nm) 、0.057瓦的藍光(450 nm)。
Chen, Bo-Rui, and 陳柏睿. "Fiber-Wireless and Fiber-IVLLC Convergences Based on MZM-OEO-Based BLS." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/a2q2f8.
國立臺北科技大學
光電工程系研究所
104
The fast development of optical communications has raised the requirements for high bandwidth and high-speed data access not only for single-mode fiber (SMF)-based optical fiber backbone but also for radio-frequency (RF)/optical wireless-based feeder networks. Through the large bandwidth of optical fiber and the flexibility of RF/optical wireless transmission, fiber-wireless and fiber-invisible laser light communication (IVLLC) convergences have progressed to meet multiple gigabit demands. Fiber-wireless and fiber-IVLLC convergences can utilize the advantages of both optical and wireless technologies; that is, they can use the naturally enormous bandwidth of optical fiber and the unused bandwidth in microwave (MW) and millimeter-wave (MMW) bands. Fiber-wireless and fiber-IVLLC convergences can cover service areas with faster speed and lower cost by virtue of fiber long-haul and RF/optical wireless short-range technologies. In this thesis, fiber-wireless and fiber-IVLLC convergences based on MZM-OEO-based BLS to transmit downstream 10 Gbps/30 GHz MW, 15 Gbps/50 GHz MMW, 20 Gbps/60 GHz MMW, and 25 Gbps/100 GHz MMW data signals, as well as upstream 25 Gbps baseband (BB) data stream, are proposed and experimentally demonstrated. Through a comprehensive investigation of such bidirectional fiber-wireless and fiber-IVLLC convergences, Bit error rate (BER) performs efficiently in a 40-km SMF and a 10-m RF/25-m optical/100-m optical wireless transport scenarios. Such fiber-wireless and fiber-IVLLC convergences for MW/MMW/BB signal transmission will be an attractive approach for providing broadband-integrated services, including Internet, telecommunication, and data communication services.
Gill, Kamalpreet Kaur. "Graded-index fibre-based absorption spectroscopy using microfluidic devices." Master's thesis, 2021. http://hdl.handle.net/10451/51691.
In recent years, increasing efforts of developing novel micro and nano technologies have been dedicated to improve human health. These advances in the field of nanotechnology have facilitated the development of miniaturized microfluidic lab-on-a-chip (LOC) devices, which are frequently described as miniature versions of their macro-scale counterparts. Microfluidic LOC devices present great benefits in terms of small sample volumes and fast analysis times. From an optical point of view, these devices still suffer a drastic reduction in the optical pathlength compared to macroscale experiments. Obviously the reduced optical pathlength complicates or reduces the effectiveness of the application of various optical techniques in lab-on-a-chip systems. Meanwhile these devices are gaining a broader acceptance in clinical medicine for disease diagnosis. This thesis describes the recent work performed in the field of optofluidics with the application of optical sensing systems for microfluidic devices. Optofluidics is a combination of optics/photonics and microfluidics field. In optofluidic devices the micro-photonic components are integrated on microfluidic devices, which are able to hold the fluids at the microlitre scale. Optofluidic devices are used to perform interactions between light and fluids at micro scale level for applications in physics, chemistry and biology. These chip-scale devices could be easily integrated into a LOC system that is a compact platform and does not require free-space optics to perform laser-based spectroscopy, such as absorption spectroscopy. Absorption spectroscopy (AS) is a powerful technique for studies of species (atoms and molecules) and detection of unknown concentrations. The spectroscopic analysis is not only applied in physics and chemistry but also in biology and medicine [1]. Although a large number of molecular species can successfully be detected with established AS techniques, there are some applications that require higher sensitivity, selectivity and accuracy, yet robust and compact instrumentation. In this work, a LOC device was developed based on the optofluidics concept. The relevance of integration of micro-optical components in an “on-chip” approach is compared with the “off-chip” approach which was coupled with macro-scale optical infrastructure. The design and characterization of miniaturized optofluidic devices for sensing based on integrating collimating optical fibers with custom microfluidic chips is presented. The usage of graded-index (GRIN) fiber tips or GIF tips is to develop a compact device which does not require free space optics and the collection efficiency of GRIN fiber tips is significantly higher compared to standard single-mode fiber. The absorption spectroscopy on-chip is performed with both GIF tips and SMF configurations. To compare the performance of both fibres, the beam divergence and the insertion losses were measured. The reduction in both beam divergence and insertion losses for the GIF configuration compared with SMF were found to be 4-fold, for a 10 mm channel. Absorption spectroscopy was demonstrated on chip for the measurement of red colour dye (Ponceau 4R) and the detection of thiocyanate (SCN) which is an indicator of oral health and a detoxification product of cancer treatments. The thiocyanate concentrations were detected in water and also in a complex biofluid i.e. artificial human saliva. The proposed optofluidic setup allows for absorption spectroscopy measurements to be performed with only 200 µL of solution which is an order of magnitude smaller than for standard cuvettes but provides comparable sensitivity. To assess the performance of the miniaturized device, the absorption measurements are also compared with a standard cuvette of the same pathlength (~10 mm). A quantitative comparison of both devices demonstrates the consistency of linearity of absorbance against the concentration of analyte, accordingly to the Beer-Lambert law. The demonstrated approach has the potential to be used for chemical and biochemical analysis of DNA, proteins or saliva where the use of small volumes is critical. In order to perform spectroscopic analysis of human body proteins, a new sensing device was developed using a compacted chip with micropillar arrays called “Pillar Cuvette (PC)”. The PCs are fabricated at ANFF-SA (Australian National Fabrication Facility - South Australia Node). The design and fabrication process of PCs is briefly presented in this thesis. The CLIC3-HIS tag protein (human body protein) and BSA protein (Bovine protein) spectroscopic analysis were performed in UV range of spectrum. We developed a new approach to optical manipulation of excitation fibre and collection fiber setup. The proposed design and setup are presented in which optical fibers and the PC are integrated directly on a compact platform that doesn’t require alignment. It is an integrated pre-aligned device which is wholly portable.
Nos últimos anos, os esforços crescentes de desenvolvimento das novas tecnologias têm-se dedicado a melhorar a saúde humana. Esses avanços no campo da nanotecnologia facilitaram o desenvolvimento de dispositivos microfluídicos, designados lab-on-a-chip (LOC), que são frequentemente descritos como versões em miniatura de seus equivalentes em macro escala. A área dos microfluídicos trata dos fluidos em escala micrométrica para fins de controlo de fluxo ou deteção das espécies químicas. Os dispositivos microfluídicos apresentam grandes vantagens, incluindo consumo mínimo de volumes de amostra, tempos de análise rápidos e custo de fabricação reduzido [2]. Com o avanço nas tecnologias de fabricação, as áreas de ótica e da fotónica também se adaptaram para desenvolver componentes óticos na micro e nano escala. A pesquisa na escala micrométrica deu origem a outro tópico chamado opto-fluídos. A área de opto-fluídos é muito recente, surgiu apenas no início de ano 2000 e a pesquisa neste tópico está crescendo exponencialmente de um ano para o outro [3]. A área de opto-fluídos estuda a interação entre fluído e luz, aproveitando a tecnologia existente nas áreas de microfluídicos da ótica. Os dispositivos opto-fluídos são geralmente baseados na integração de tecnologias óticas/fotónicas no dispositivo microfluídico. Do ponto de vista ótico, os dispositivos opto-fluídos sofrem uma redução drástica no comprimento do caminho ótico, em comparação com os instrumentos em macro escala. Obviamente, o comprimento do caminho ótico reduzido complica ou traz problemas na utilização de técnicas de deteção e isso, por sua vez, reduz a eficácia das técnicas óticas em sistemas LOC. Enquanto isso, esses dispositivos estão a ganhar aceitação crescente no campo da medicina clínica para o diagnóstico de várias doenças. A presente tese descreve o trabalho recente realizado na área de opto-fluídos, utilizando um sistema de sensores óticos num dispositivo microfluídico. Os dispositivos opto-fluídicos são usados para realizar interações entre luz e fluídos em nível de microescala para aplicações em física, química e biologia. Os componentes óticos ao nível de escala de um micro-chip podem ser facilmente integrados em um sistema LOC que também é uma plataforma compacta. Deste modo, os sistemas opto-fluídos não requerem ótica de espaço livre para realizar espectroscopia baseada em laser, como a espectroscopia de absorção. A espectroscopia de absorção é uma técnica poderosa para estudos de espécies (átomos e moléculas) e deteção de concentrações desconhecidas. Embora um grande número de espécies moleculares possa ser detetado com sucesso através das várias técnicas estabelecidas de espectroscopia, existem algumas aplicações que requerem maior sensibilidade, precisão e instrumentação mais robusta e compacta. Neste trabalho pretendeu-se desenvolver um dispositivo LOC com base no conceito de opto-fluídos. A espectroscopia de absorção foi demonstrada no dispositivo compacto e miniaturizado (LOC) desenvolvido usando fibras que têm pontas de índice graduado (GRIN) que também são conhecidas por pontas GIF. Essas fibras permitem desenvolver um lab-on-a-chip altamente eficaz que é compacto, conectada por fibra e que não requer ótica de espaço livre para criar o caminho ótico. A espectroscopia de absorção no chip é realizada com duas configurações, ou seja, pontas GIF e SMF. Para comparar o desempenho de ambas as fibras, a divergência do feixe e as perdas de inserção foram medidas. A eficiência de coleção do feixe na ponta de fibra GRIN (125 µm) é significativamente maior em comparação com a fibra de modo único - SMF (125 µm). As pontas GIF têm o feixe colimado na saída da fibra que é transmitida longitudinalmente através de um microcanal e que é coletada por uma fibra multi-modo na outra extremidade do microcanal. Desta forma, fabricamos um dispositivo opto-fluídico que permite melhorias significativas no aumento do comprimento de interação, para espectroscopia de absorção de passagem única, usando pontas de fibra de índice graduado (GIF). A relevância da integração de componentes micro-óticos na abordagem on-chip é comparada com a abordagem off- chip, que foi acoplada à infraestrutura ótica em macro escala. A configuração opto-fluídica proposta permite que as medições de espectroscopia de absorção sejam realizadas com apenas 200 µL de solução, que é uma ordem de magnitude menor do que as efetuadas com uma cuvete padrão (3.5 mL), mas que fornece sensibilidade comparável. Para avaliar o desempenho do dispositivo miniaturizado, as medições de absorção também são comparadas com uma cuvete padrão do mesmo caminho ótico (~10 mm). A espectroscopia de absorção foi demonstrada em 3 configurações (cuvete padrão; dispositivo opto-fluídico com fibra SMF; dispositivo opto-fluídico com fibra GIF) para a medição do corante vermelho (Ponceau 4R). Para demonstrar ainda mais o uso do dispositivo opto-fluídico, mostramos que esse pode ser usado para a deteção de analitos biologicamente relevantes, como o thiocyanate (SCN). O SCN foi escolhido porque é um produto usado na desintoxicação de fármacos utilizados no tratamento do cancro e é um indicador de saúde bucal, incluindo a exposição ao fumo passivo que pode aumentar significativamente as concentrações de SCN para níveis potencialmente capazes de afetar a glândula tireoide. Numa comparação quantitativa, o dispositivo demonstrou a consistência da linearidade da absorbância em relação à concentração do analito, de acordo com a lei de Beer-Lambert Também exploramos a configuração opto fluídica com a ponta GIF para deteção de SCN em uma matriz de uma amostra mais complicada (que não é apenas água) a saliva humana artificial. Reforçando assim, o estudo do potencial deste dispositivo para diagnóstico de amostras complexas. A abordagem demonstrada mostrou ter potencial para ser usada para análises químicas e bioquímicas de ADN, proteínas ou saliva onde o uso de pequenos volumes é crítico. De modo a fazer comparação entre duas fibras, foram efetuados estudos de feixe de divergência ao longo de microcanal e as perdas de inserção entre a fibra de excitação (GIF) e a fibra de coleção (MMF). Foi obtida uma redução 4 vezes inferior na divergência do feixe e nas perdas de inserção para a configuração GIF em comparação com SMF, para um canal de 10 mm de comprimento. O trabalho foi complementado com a análise espectroscópica das proteínas do corpo humano. Para tal, foi utilizado um chip compactado com matrizes de micropilares denominado Pillar Cuvette ou PC. Os PC foram fabricados na ANFF- SA (Australian National Fabrication Facility - South Australia Node). O processo de desenho e fabricação do PC é brevemente apresentado neste trabalho. A análise espectroscópica da proteína CLIC3-HIS tag (proteína do corpo humano) e da proteína BSA (proteína bovina) foi realizada na faixa de espectro do ultravioleta (UV). Utilizando os métodos prévios não foi possível determinar o pico de absorvância esperado a λ=280 nm. Face a este resultado, foi desenvolvido um novo dispositivo opto fluídico que tem alta viabilidade de integração na plataforma lab-on-a-chip. Neste novo dispositivo as pontas GIF são configuradas num PC. Na nova configuração desenvolvida, o feixe é transmitido através da secção transversal do PC, permitindo aumentar o comprimento do caminho ótico mantendo 2 µL - 3 µL de volume de amostra. Para futuro trabalho, o desenho de uma plataforma foi desenvolvido para integração compacta dos PC e das ambas as fibras. Esta nova plataforma está em processo de fabricação e será testado nas futuras experiências. Um bom resultado nos testes permitirá alargar o universo de utilização destes dispositivos em análises químicas e bioquímicas com volume de amostra e tempo de análise reduzido. Deste modo, a crescente disponibilidade de ferramentas e técnicas na indústria de nanotecnologia vai fornecer um caminho para trazer essas inovações do laboratório para a vida cotidiana.