Diffraction based phase compensation method for phase-only liquid crystal on silicon devices in operation.
A method to measure the optical response across the surface of a phase-only liquid crystal on silicon device using binary phase gratings is described together with a procedure to compensate its spatial optical phase variation. As a result, the residual power between zero and the minima of the first diffraction order for a binary grating can be reduced by more than 10 dB, from -15.98 dB to -26.29 dB. This phase compensation method is also shown to be useful in nonbinary cases. A reduction in the worst crosstalk by 5.32 dB can be achieved when quantized blazed gratings are used.
Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK.
Zichen
Z
Zhang
Haining
H
Yang
Brian
B
Robertson
Maura
M
Redmond
Mike
M
Pivnenko
Neil
N
Collings
William A
WA
Crossland
Daping
D
Chu