Título: | DEVELOPMENT AND CHARACTERIZATION OF A CHOLESTERIC LIQUID CRYSTAL LASER SYSTEM COUPLED TO AN OPTICAL FIBER | |||||||
Autor: |
MICHELE FIGUEIREDO MOREIRA |
|||||||
Colaborador(es): |
ISABEL CRISTINA DOS SANTOS CARVALHO - Orientador PETER PALFFY MUHORAY - Coorientador |
|||||||
Catalogação: | 10/AGO/2004 | Língua(s): | PORTUGUESE - BRAZIL |
|||||
Tipo: | TEXT | Subtipo: | THESIS | |||||
Notas: |
[pt] Todos os dados constantes dos documentos são de inteira responsabilidade de seus autores. Os dados utilizados nas descrições dos documentos estão em conformidade com os sistemas da administração da PUC-Rio. [en] All data contained in the documents are the sole responsibility of the authors. The data used in the descriptions of the documents are in conformity with the systems of the administration of PUC-Rio. |
|||||||
Referência(s): |
[pt] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/ETDs/consultas/conteudo.php?strSecao=resultado&nrSeq=5261&idi=1 [en] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/ETDs/consultas/conteudo.php?strSecao=resultado&nrSeq=5261&idi=2 |
|||||||
DOI: | https://doi.org/10.17771/PUCRio.acad.5261 | |||||||
Resumo: | ||||||||
In this work, we have studied the viability of developing a
cholesteric liquid crystal (CLC) laser system coupled into
an optical fiber aiming its application as temperature
sensor. Sensors made of CLC laser coupled to optical fibers
are a very attractive proposition due to the enormous
advantages of the optical fibers and the response of the
liquid crystal to various external stimuli. The laser
emission occurs at the low energy edge of the reflection
band, and the corresponding wavelength is determined by the
pitch and the extraordinary refractive index. These
parameters can be altered by a change in the external
temperature, leading to variations in the wavelength of the
CLC laser emission, which can be used to monitor the
external temperature. We obtained a stable laser emission
in a CLC laser system coupled into an optical fiber when
pumped by the second harmonic of a Nd:YAG laser. A technique
to anchor the liquid crystal at the optical fibers ends was
developed. The temperature dependence of the laser emission
was investigated in two situations, placing the CLC laser
between optical fibers and into the glass cells. Several
liquid crystals were studied in order to optimize the laser
response with temperature. Discrete variations in the
temperature dependence of the laser emission wavelength
were observed when the glass cell system was used. We
associated this behavior to a temperature dependence of the
surface anchoring of the liquid crystal molecules in the
glass surface.
|
||||||||