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Optical phased arrays (OPAs) on integrated photonic platforms provide a low-cost chip-scale solution for many applications. Despite the numerous demonstrations of OPA transmitters, the realization of a functional OPA receiver presents a challenge due to the low received signal level in the presence of noise and interference that necessitates high sensitivity of the receiver. In this paper, an integrated receiver system is presented that is capable of on-chip adaptive manipulation and processing of the captured waveform. The receiver includes an optoelectronic mixer that down-converts optical signals to radio frequencies while maintaining their phase and amplitude information. The optoelectronic mixer also provides conversion gain that enhances the system sensitivity and its robustness to noise and interference. Using this system, the first OPA receiver with a two-dimensional aperture of 8-by-8 receiving elements is demonstrated which can selectively receive light from 64 different angles. The OPA receiver can form reception beams with a beamwidth of 0.75 ° over an 8 ° grating-lobe-free field of view.

In this paper we provide the design details of self-equalizing photodetectors which enable higher data rate transmission by improving the overall bandwidth of the bandwidth limited transmission link, through a hybrid electro-optical solution. Two different self-equalizing photodiodes, one having fixed equalization and the other being programmable are presented as proof of concept.

Low-power integrated projection technology can play a key role in development of low-cost mobile devices with built-in high-resolution projectors. Low-cost 3D imaging and holography systems are also among applications of such a technology. In this paper, an integrated projection system based on a two-dimensional optical phased array with fast beam steering capability is reported. Forward biased p-i-n phase modulators with 200MHz bandwidth are used per each array element for rapid phase control. An optimization algorithm is implemented to compensate for the phase dependent attenuation of the p-i-n modulators. Using rapid vector scanning technique, images were formed and recorded within a single snapshot of the IR camera.

An integrated silicon nanophotonic coherent imager (NCI), with a 4 × 4 array of coherent pixels is reported. In the proposed NCI, on-chip optical processing determines the intensity and depth of each point on the imaged object based on the instantaneous phase and amplitude of the optical wave incident on each pixel. The NCI operates based on a modified time-domain frequency modulated continuous wave (FMCW) ranging scheme, where concurrent time-domain measurements of both period and the zero-crossing time of each electrical output of the nanophotonic chip allows the NCI to overcome the traditional resolution limits of frequency domain detection. The detection of both intensity and relative delay enables applications such as high-resolution 3D reflective and transmissive imaging as well as index contrast imaging. We demonstrate 3D imaging with 15μm depth resolution and 50μm lateral resolution (limited by the pixel spacing) at up to 0.5-meter range. The reported NCI is also capable of detecting a 1% equivalent refractive index contrast at 1mm thickness.