Title :
Phase-shifting VOA with polymer dispersed liquid crystal
Author :
Chanclou, P. ; Vinouze, B. ; Roy, M. ; Cornu, C. ; Ramanitra, H.
Author_Institution :
GET-ENST Bretagne Dept. d´´Opt., Brest, France
Abstract :
A polymer containing fine droplets of liquid crystal (LC) is investigated for obtaining an optical phase-shifting attenuator at 1550-nm wavelength. Two mixtures of liquid crystals and monomers are compared for a cell thickness of 15 μm. The first method uses nanosized LC droplets to achieve 2.29-rad phase shifting for an applied voltage of 230 Vrms. The second method uses microsized LC droplets to achieve 2.35-rad phase shifting for an applied voltage of 15 Vrms. Theoretical analysis of the phase shifting is developed. This optical property is used to achieve a variable optical attenuator (VOA) between two single-mode fibers. An optical architecture using graded index rod lenses and a pattern of photoresist polymer is presented. Typical characteristics of such VOA are: 12-dB range of attenuation, a maximum polarization dependence loss of 0.5 dB, 1.1-dB insertion loss, and a saturation voltage of 20 Vrms.
Keywords :
electro-optical devices; gradient index optics; lenses; micro-optics; optical attenuators; optical communication equipment; optical fabrication; optical fibre communication; optical fibres; optical losses; optical phase shifters; photoresists; polymer dispersed liquid crystals; 0.5 dB; 1.1 dB; 12 dB; 15 V; 15 mum; 1550 nm; 2.35 V; 20 V; graded index rod lenses; microsized LC droplets; nanosized LC droplets; optical phase-shifting; phase-shifting VOA; photoresist polymer; polymer dispersed liquid crystal; single mode fibers; variable optical attenuator; Lenses; Liquid crystal polymers; Liquid crystals; Optical attenuators; Optical fiber polarization; Optical losses; Optical polymers; Optical saturation; Resists; Voltage;
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2003.821719
