Practical two-dimensional beam steering system using an integrated tunable laser and an optical phased array

A practical two-dimensional beam steering solid-state system based on the synthesis of one-dimensional wavelength tuning and a one-dimensional optical phased array is demonstrated and investigated. The system incorporates an integrated multiple-channel-interference widely tunable laser, an integrated 32-channel optical phased array, an offline phase error correction unit, and home-made control electronics. The introduction of the integrated tunable laser avoids the traditional bulky light source fed into the optical phased array, making the architecture promising to be miniaturized. In addition, a calibration method based on particle swarm optimization is proposed and proved to be effective to correct the phase errors existing in the arrayed channels and improve the emitted far-field quality. Other practical aspects, such as high-speed control and cost, are taken into the consideration of the system design as well. Under the control of home-made electronics, the laser exhibits a tuning range of 50 nm with a 44 dB side-mode suppression ratio, and the system presents the characteristics of low divergence (0.63 degrees x 0.58 degrees), high side-lobe suppression ratio (>10 dB), and high-speed response (<10 gs time constant) in an aliasing-free sweeping range of 18 degrees x 7 degrees. (C) 2020 Optical Society of America