Author_Institution :
Sch. of Opt. & Electron. Inf., Huazhong Univ. of Sci. & Technol., Wuhan, China
Abstract :
We propose and experimentally demonstrate a robust mode converter based on liquid crystal-on-silicon (LCOS), which is not placed at the focal plane of the collimating lens. We present theoretical investigations to evaluate the performance of proposed configuration, and our experimental results verify the favorable function of mode-selective conversion with orthogonal linear polarizations, as well as two-mode multiplexing. The robust device configuration with an insertion loss of less than 3 dB, together with cascade capability, can be used for multidimensional fiber-optical transmission system. In particular, in terms of LP11 mode conversion, the off-focus operation allows the range of position offset for input fiber with graded-index (GRIN) lens, LCOS, and few-mode fiber to be 7.5 mm, 151 μm, and 40.4 mm, respectively, indicating easy alignment and maintenance.
Keywords :
gradient index optics; integrated optics; integrated optoelectronics; lenses; light polarisation; liquid crystal on silicon; multiplexing; optical communication equipment; optical fibre communication; optical focusing; optical losses; GRIN; LCOS; LP11 mode conversion; cascade capability; collimating lens; focal plane; graded-index lens; insertion loss; liquid crystal-on-silicon; mode-selective conversion; multidimensional fiber-optical transmission system; off-focus operation; orthogonal linear polarizations; robust mode converter; two-mode multiplexing; Focusing; Lenses; Liquid crystal on silicon; Multiplexing; Optical diffraction; Optical fiber devices; Optical fiber polarization; LCOS; Mode division multiplexing; Mode selective conversion; Mode-division multiplexing; Off-focus operation; mode-selective conversion; off-focus operation;
