PHOTOREFRACTIVE BEAM SPLITTER FOR FREE-SPACE OPTICAL INTERCONNECTIONS

A photorefractive beam splitter (PRBS) is introduced as an alternative to a polarizing beam splitter (PBS) for coupling optical power into r eflective modulators in a free-space optical interconnection system. T he PRES uses a single diffraction grating recorded in a photorefractiv e material to redirect the incident laser light into the first diffrac tion order and onto the modulators. Reflected interconnection light no t matching the Bragg angle criteria transmits uncoupled through the be am splitter. Experimental results show that the PRES provides better, more uniform transmission for off-axis beams than the currently used P BS. (C) 1998 Optical Society of America.