ANALYSIS OF BEAM-STEERING WITH DECENTERED MICROLENS ARRAYS

A cascade of microlens arrays that are decentered with respect to each other is one potential method for beam steering; the magnitude of the steering depends on the amount of decenter. A simple, heuristic geome tric analysis is presented that suggests that the output of the arrays is analogous to a blazed grating. The periodic nature of the exiting wavefront restricts allowed steering angles to values determined by th e element-to-element spacing of the microlens arrays. The efficiency o f steering into a desired mode of the grating is determined both by th e amount of decenter of the microlens arrays and the fill factor at th e output of the arrays. It is shown that maximum fill factor is desire d, which can be achieved through the addition of a microlens array tha t acts like a field lens. Assumptions are identified under which the g rating nature of the output can be predicted using Fresnel diffraction theory. Future work in the area of microlens beam steering is suggest ed.