Title :
Virtually imaged phased array with graded reflectivity
Author :
Shirasaki, M. ; Akhter, A.N. ; Lin, C.
Author_Institution :
MIT, Cambridge, MA, USA
Abstract :
A virtually imaged phased array (VIPA) can produce large angular dispersion, i.e., change in output angle with change in wavelength. The insertion loss and crosstalk of the VIPA demultiplexer are analyzed. It is shown that both characteristics are significantly improved by modifying the reflectivity on the VIPA element. With a graded reflectivity instead of a uniform reflectivity, the mode coupling efficiency to the output fiber is improved from 80%99.5% and the crosstalk Is reduced from -23 to -59 dB.
Keywords :
demultiplexing equipment; optical arrays; optical crosstalk; optical fibre couplers; optical fibre dispersion; optical images; reflectivity; VIPA demultiplexer; VIPA element; crosstalk; graded reflectivity; insertion loss; large angular dispersion; mode coupling efficiency; output fiber coupling; reflectivity; uniform reflectivity; virtually imaged phased array; Crosstalk; Diffraction gratings; Optical diffraction; Optical fiber dispersion; Optical propagation; Optical surface waves; Optical waveguides; Phased arrays; Reflectivity; Wavelength division multiplexing;
Journal_Title :
Photonics Technology Letters, IEEE
