Birefringent waveguide sensor using a polarizer rotating technique.
A birefringence measurement system is introduced to get high phase resolution for detection of low contents of biochemicals. By using a fixed quarter-wave plate and a rotating polarizer, the phase difference between two orthogonal polarizations is transformed into phase delay of output sinusoidal signal. Analyzing the output phase, birefringence change could be detected with a phase noise of 0.14 degrees. As well as the birefringence measurement system, an optical evanescent waveguide sensor was developed. A rib-type silica waveguide overlaid with TiO2 film was fabricated, and a developed birefringence measurement technique was employed in evaluating a refractive index change on waveguide surface. For the fabricated waveguide with a 40-nm-thick TiO2 film, experiment results showed that the minimum detectable index change was 5.9x10(-7).
Son
Geun-Sik
GS
Department of Electronic Engineering, Kwangwoon University, Seoul, South Korea.
Kim
Woo-Kyung
WK
Yang
Woo-Seok
WS
Lee
Hyung-Man
HM
Lee
Han-Young
HY
Lee
Sung-Dong
SD
Jeong
Woo-Jin
WJ
Kwon
Soon-Woo
SW
Kim
Ye-na
YN
Lee
Sang-Shin
SS
D001718:Birefringence; D012031:Refractometry / Q000295:instrumentation* / Q000379:methods*; D012399:Rotation; D013499:Surface Properties; D014025:Titanium
C009495:titanium dioxide; D014025:Titanium