Programmable Multi-Beam Steering with Optical Phased Array

Optical phased array provides a promising platform for multi-beam steering in optical bands. Here, we propose and demonstrate an effective multi-beam steering scheme employing a phase-only spatial light modulator. The beam orientations and beam amplitudes are both programmable in our proposal. With Huygens-Fresnel simulation, the fidelity value of similar to 0.998 and similar to 0.999 are evaluated corresponding to the case of random beam orientations and random beam amplitude ratios, respectively. Furthermore, up to 101-beam steering is experimentally observed, which is much higher than existed reports.