Sensitivity versus polarisation in multilayer optical thin film design
The design of a polarised optical filter is more complicated than that of a filter where the polarisation effect does not exist (at a normal angle of incidence). An error in the optical parameters, such as the physical thickness or refractive index of a layer, results in a change in the spectral...
Main Authors: | , |
---|---|
Format: | Article |
Language: | English |
Published: |
Academy of Science of South Africa
2012-07-01
|
Series: | South African Journal of Science |
Subjects: | |
Online Access: | https://www.sajs.co.za/article/view/9809 |
_version_ | 1818849894867140608 |
---|---|
author | Efrem Ejigu Beartys Lacquet |
author_facet | Efrem Ejigu Beartys Lacquet |
author_sort | Efrem Ejigu |
collection | DOAJ |
description | The design of a polarised optical filter is more complicated than that of a filter where the polarisation effect does not exist (at a normal angle of incidence). An error in the optical parameters, such as the physical thickness or refractive index of a layer, results in a change in the spectral performance of the multilayer structure. The correlation between error sensitivity and the polarisation effect of light in structures designed at an oblique angle was investigated. To illustrate the correlation, a perpendicular (S) and parallel (P) polarised beam splitter, at 0.9818 µm central wavelength, designed by genetic algorithm, was used. The beam splitter changes its state of polarisation according to the error in thickness simultaneously induced in each of the layers. The error was calculated by optimising the original design. The observation of the change of the state of polarisation as a result of error sensitivity leads to a different method of designing pure S-polarised or P-polarised optical filters. |
first_indexed | 2024-12-19T06:40:30Z |
format | Article |
id | doaj.art-c61a69a493424cdd994e9c69304aea39 |
institution | Directory Open Access Journal |
issn | 1996-7489 |
language | English |
last_indexed | 2024-12-19T06:40:30Z |
publishDate | 2012-07-01 |
publisher | Academy of Science of South Africa |
record_format | Article |
series | South African Journal of Science |
spelling | doaj.art-c61a69a493424cdd994e9c69304aea392022-12-21T20:32:06ZengAcademy of Science of South AfricaSouth African Journal of Science1996-74892012-07-011087/8Sensitivity versus polarisation in multilayer optical thin film designEfrem Ejigu0Beartys Lacquet1Department of Electrical and Electronics Engineering Science, University of Johannesburg, JohannesburgFaculty of Engineering and the Built Environment, University of the Witwatersrand, JohannesburgThe design of a polarised optical filter is more complicated than that of a filter where the polarisation effect does not exist (at a normal angle of incidence). An error in the optical parameters, such as the physical thickness or refractive index of a layer, results in a change in the spectral performance of the multilayer structure. The correlation between error sensitivity and the polarisation effect of light in structures designed at an oblique angle was investigated. To illustrate the correlation, a perpendicular (S) and parallel (P) polarised beam splitter, at 0.9818 µm central wavelength, designed by genetic algorithm, was used. The beam splitter changes its state of polarisation according to the error in thickness simultaneously induced in each of the layers. The error was calculated by optimising the original design. The observation of the change of the state of polarisation as a result of error sensitivity leads to a different method of designing pure S-polarised or P-polarised optical filters.https://www.sajs.co.za/article/view/9809SensitivityS and P-polarisationerrorgenetic algorithmoptimisation |
spellingShingle | Efrem Ejigu Beartys Lacquet Sensitivity versus polarisation in multilayer optical thin film design South African Journal of Science Sensitivity S and P-polarisation error genetic algorithm optimisation |
title | Sensitivity versus polarisation in multilayer optical thin film design |
title_full | Sensitivity versus polarisation in multilayer optical thin film design |
title_fullStr | Sensitivity versus polarisation in multilayer optical thin film design |
title_full_unstemmed | Sensitivity versus polarisation in multilayer optical thin film design |
title_short | Sensitivity versus polarisation in multilayer optical thin film design |
title_sort | sensitivity versus polarisation in multilayer optical thin film design |
topic | Sensitivity S and P-polarisation error genetic algorithm optimisation |
url | https://www.sajs.co.za/article/view/9809 |
work_keys_str_mv | AT efremejigu sensitivityversuspolarisationinmultilayeropticalthinfilmdesign AT beartyslacquet sensitivityversuspolarisationinmultilayeropticalthinfilmdesign |