A 1-D heterodyne lens-free optical phased array camera with reference phase shifting
This paper presents the first integrated silicon photonics optical phased array (OPA) receiver with imaging capabilities. A 32-element 1D OPA with an overall aperture size of 96x50 μm^2 is used to generate an electrically steerable "gazing beam". The OPA receiver elements couple the incident light to on-chip waveguides which is processed as a phased array receiver. To minimize signal loss and enhance sensitivity, a heterodyne architecture with phase shifters in the local reference path is utilized. The OPA receiver can provide fully programmable angular selectivity with a grating-lobe-free field-of-view of 30° and a gazing beamwidth of 0.74°.
© 2018 IEEE. IEEE Open Access. Manuscript received July 6, 2018; revised September 17, 2018; accepted September 17, 2018. Date of publication September 26, 2018; date of current version October 12, 2018. This research was supported by Caltech Innovation Initiative. This paper was presented in part at the National Science Foundation, Alexandria, VA, USA. The authors would like to thank OpSIS and Drs. T. Baehr-Jones and M. Hochberg for assistance with chip fabrication and Aroutin Khachaturian for help in measurement setup preparation.
Published - 08471238.pdf