Article ID Journal Published Year Pages File Type
1541983 Optics Communications 2007 5 Pages PDF
Abstract
We demonstrate that in addition to their role in tuning the wavelength of an N-stage hybrid liquid-crystal Å olc filter, liquid-crystal cells can also be used to vary the transmission bandwidth of such filter around any of the tuned wavelength. This bandwidth tuning is based on the variation of the number of stages by what we call here an “optical cancelling technique”. This is achieved by varying the birefringence of the liquid-crystal cells whose optical path difference switches between two particular values. We show that for a 10-stage filter and at λi = 1.532 μm, the calculated 3-dB bandwidth varies from 2.6 to 11.8 nm when the number of “optically-cancelled” hybrid plates increases from 0 to 8. During the tuning process, the contrast ratio remains equal to that of the equivalent classical Å olc filter.
Related Topics
Physical Sciences and Engineering Materials Science Electronic, Optical and Magnetic Materials
Authors
, , , ,