Physics

Fabrication

Pathology

Beam steering

Chip

Spatial light modulator

Optics

Liquid-crystal display

Beam (structure)

Phased-array optics

Antenna (radio)

Materials science

Alternative medicine

Photonics

Computer science

Liquid crystal on silicon

Optoelectronics

Phased array

Wavelength

Medicine

Telecommunications

Optics Letters

Compact beam steering in the visible spectral range is required for a wide range of emerging applications, such as augmented and virtual reality displays, optical traps for quantum information processing, biological sensing, and stimulation. Optical phased arrays (OPAs) can shape and steer light to enable these applications with no moving parts on a compact chip. However, OPA demonstrations have been mainly limited to the near-infrared spectral range due to the fabrication and material challenges imposed by the shorter wavelengths. Here, we demonstrate the first chip-scale phased array operating at blue wavelengths (488 nm) using a high-confinement silicon nitride platform. We use a sparse aperiodic emitter layout to mitigate fabrication constraints at this short wavelength and achieve wide-angle beam steering over a 50° field of view with a full width at half-maximum beam size of 0.17°. Large-scale integration of this platform paves the way for fully reconfigurable chip-scale three-dimensional volumetric light projection across the entire visible range.

Chip-scale blue light phased array