Relief Gratings
Mostrando 1-8 de 8 artigos, teses e dissertações.
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1. Estudo e aplicações de filmes fotosensitivos de vidros óxidos e sulfeto de germânio / Study and applications of oxysulphide sensitive films
Neste trabalho foram estudados os fenômenos fotoinduzidos apresentados pelos filmes oxisulfetos de composição: 90% GeS2 + 10% Ga2 O3. Os filmes foram depositados em substrato de borosilicato pela técnica de evaporação por feixe de elétrons. A partir dos espectros de transmissão, a energia do bandgap, o índice de refração e a espessura foram determ
Publicado em: 2008
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2. Double diffraction white light imaging without intermediary elements / Imagem por dupla difração com luz branca sem elementos intermediarios
We present the analysis of the formation of images by diffractive elements using white light by performing ray-tracing through main directions. The first system we describe is composed of two diffraction gratings and a slit, the second by two bi-dimensional spiral elements and a hole aperture, generating ortoscopic (natural relief) images. From this we had f
Publicado em: 2007
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3. Estudo e aplicações do fenômeno de absorção de dois fótons em moléculas azo-aromáticas / Studies and applications of two-photon absorption in azo-aromatic molecules
Here we investigated fundamental and applied aspects of the two-photon absorption process in azoaromatic compounds. Azoaromatic molecules have been studied in the last few years due to their applications in optical storage devices, light modulators and surface relief gratings, processes related to the photo-isomerization mechanism. The main focus of the resu
Publicado em: 2007
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4. Inscription of local surface relief gratings with a Scanning Near-field Optical Microscope on an azo-polymer film
A Scanning Near-field Optical Microscope (SNOM) was used to inscribe locally limited Surface Relief Gratings (SRGs) on pDR1M, which is an azo-polymer film. The influence of parameters such as the line scanning time and the line spacing on the amplitude and the period of the gratings is discussed. SRGs have been used to orient Liquid Crystals (LCs), where the
Polímeros. Publicado em: 2006-12
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5. Estudo da orientação molecular em filmes automontados de azopolímeros por meio da técnica de geração de segundo harmônico (SHG) / Molecular orientation in self-assembled azo-polymer thin films studied by second harmonic generation (SHG).
Ultrathin films of polymers containing azochromophores are important for many applications such as optical data storage, formation of surface relief gratings, liquid crystal alignment layers and non-linear optical devices. Among several techniques for fabricating organic thin films, the Layer-By-Layer electrostatic self-assembly (LBL) is very attractive due
Publicado em: 2006
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6. AVALIAÇÃO METROLÓGICA DE ACELERÔMETRO ÓPTICO UTILIZANDO REDE DE BRAGG: APLICAÇÃO EM LINHAS DE TRANSMISSÃO DE ENERGIA ELÉTRICA / METROLOGICAL EVALUATION OF AN OPTICAL FIBER BRAGG GRATING ACCELEROMETER: APPLICATION IN OVERHEAD TRANSMISSION LINES
Overhead transmission lines play an important role on electric systems. Due to the high energy carried through those networks, failures on overhead lines can bring severe constraints on consumers supply, occasionally taking the form of blackouts in large geographic regions. Among the reasons of such failures is the breaking of electric cables caused by the f
Publicado em: 2005
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7. Estudo das propriedades de armazenamento óptico e grades de relevo em poliuretano derivado de azo-benzeno / Information optically storage and relief gratings study in material derivative of azo-benzene polyrethane
Polymers containing azobenzenic groups have been studied due to their applications on non-linear optics, surface relief gratings (SRG) and photoinduced anisotropy for optical storage. The reversal photoisomerization trans-cis-trans property of the azo group induces a molecular reorientation. In this work, cast films of na azobenzene derivative, the polyureth
Publicado em: 2003
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8. Polymeric nanocomposites containing azodyes, phthalocyanines and luminescent polymers / Compósitos poliméricos nanoestruturados de azocorantes,ftalocianinas e polímeros luminescentes
This thesis describes the fabrication and possible applications of layer-by-Iayer (LBL) nanostructured films for three distinct systems comprising i) azopolymers and azodyes, ii) organometallic molecules (phthalocyanines) and iii) luminescent polymers and azodyes. Optically induced birefringence and surface relief gratings (SRGs) were studied in the azobenze
Publicado em: 2003