Integrated optical phased array: Challenges and future trends

Integrated optical phased arrays (OPAs) enable precise, non-mechanical beam steering and have emerged as promising technology for various applications for applications spanning LiDAR, free-space optical communication, and biomedical imaging. Despite rapid progress, no existing OPA architecture simultaneously satisfies the requirements of a wide field of view, low optical loss, high power efficiency, large-scale integration, and manufacturability. This perspective paper reviews recent progress across four major OPA architectures, including 1D OPAs, 1D OPAs with wavelength tuning, 2D OPAs, and dispersive OPAs, and analyzes their operational principles, performance metrics, limitations, and application suitability. Achieving practical, high-performance, large-scale OPAs will likely require innovations in heterogeneous material integration, hybrid tuning mechanisms, on-chip optical amplification, high-filling-factor antenna designs, and monolithic photonic–electronic co-integration. This paper provides an overview of current OPAs and outlines key research directions that will shape the next generation of high-performance optical beam-steering systems.