Managing Grating Parameters for Longitudinal Steering with 1D Optical Phased Arrays

We propose and experimentally validate an efficient solution to extend the longitudinal beam steering range, managing all available diffraction parameters in the grating radiators of optical phased arrays (OPAs). Using the thermo-optic tunable radiator, varying the effective index of the grating radiator, the beam was continuously steered to a limited range. The operating wavelength was discretely changed with different wavelength sources to extend and multiply the steering range. Also, the incident direction of light was changed utilizing the bidirectional radiators shared with two subarrays of OPA to extend the steering range and mirror symmetrically. From 1×4 bidirectional OPAs consisting of p-i-n electro-optic phase shifters and MZI path switches to change the incident direction, seamless and continuous longitudinal steering was demonstrated in a range of ±6° for a transversal steering range of ±22.7° with a divergence angle of 0.5° and 1.0° in each direction.