Full text
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| Author(s): |
Giuseppe Antonio Cirino
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Escola Politécnica (EP/BC) |
| Defense date: | 2002-05-24 |
| Examining board members: |
Patrick Bernard Verdonck;
Lucila Helena Deliesposte Cescato;
Ronaldo Domingues Mansano;
Mikiya Muramatsu;
Jose Augusto de Alencar Mendes Pereira
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| Advisor: | Patrick Bernard Verdonck; Luiz Goncalves Neto |
| Abstract | |
In this work several types of diffractive optical elements (DOE) were fabricated using process steps of micro-systems fabrication, such as optical lithography and plasma etching. Process steps were developed and new materials, like amorphous hydrogenated carbon (a: C-H) thin films, were investigated. Among the fabricated devices are amplitude-only DOEs, phase-only DOEs and full complex-amplitude modulation DOEs. Materials such as monocrystaline silicon, fused silica, PMMA, Novolak-based polymer and a:C-H were studied. This work has sucessfully shown the design and implementation of a DOE not reported before in the literature yet, namely (a:C-H)-based full complex-amplitude modulation DOE. In this device the phase of an incoming laser light is modulated by a surface relief implemented on the (a:C-H) film and the amplitude modulation is achieved by removing small parts of a reflective aluminum layer deposited over the phase relief. Using this approach, the new element\'s optical performances are improved even for near field operation. With this device it is possible to obtain high efficient spatial filtering and low-noise reconstruction images. (AU) | |