The ability to integrate optical phased arrays (OPA) on a single silicon-photonics substrate offers a plethora of new opportunities in various fields, including projection and imaging. In this paper, we will discuss some of the trade-offs in the design of OPAs and their application. We investigate OPA receivers which can form and electronically steer a “gazing beam” in a desired direction. We will discuss various architectural and systems choices and present a one-dimensional (1D) OPA and a two dimensional (2D) OPA, as examples. We will demonstrate how an optical heterodyning approach can be used to improve the sensitivity of such OPA and form images directly from the surface of a silicon nano-photonic chip without any lens, additional optical components, or moving parts. We will discuss the design details of a 1D OPA RX camera with a field of view in excess of 60 with a gazing beam width of 0.74 based on a heterodyning architecture. We will also investigate the details of the design of a heterodyne 2D OPA lensless camera which can image with the gazing beam width of 0.75 and the ability to image a field of view of roughly 8 in azimuth and elevation. We will also discuss the concept and implementation of coherent imagers that can be used as highly precise 3D imagers. As an example, we will show 3D imaging at the distance of 0.5m with a resolution of 15um.