Phased array optics (PAO) is the technology of controlling the phase of light waves transmitting or reflecting from a two-dimensional surface by means of adjustable surface elements. It is the optical analog of phased array radar. By dynamically controlling the optical properties of a surface on a microscopic scale, it is possible to steer the direction of light beams, or the view direction of sensors, without any moving parts. Hardware associated with beam steering applications is commonly called an optical phased array (OPA)[1]. Phased array beam steering is used for optical switching and multiplexing in optoelectronic devices, and for aiming laser beams on a macroscopic scale.

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