A Vernier optical phased array with quasi Gaussian intensity distribution for wide field of view and high sidelobe suppression

As a key enabling solution for solid-state beam steering, optical phased array (OPA) technology holds significant potential in light detection and ranging (LiDAR) systems and free-space optical communication. In this work, we proposed a Vernier OPA transceiver implemented on a SiN-on-SOI platform that achieves simultaneous wide field of view (FOV) and high sidelobe suppression ratio (SLSR). The proposed design employs tailored power splitters to regulate channel intensity distribution and utilizes a Vernier architecture for enhanced lobe suppression within a compact 120-channel configuration comprising a 64-element transmitting array and 56-element receiving array. Meanwhile, beam transmission and reception are implemented using a SiN-Si double-layer grating antenna, which offers both a large emission aperture and high emission efficiency. Experimental results demonstrate a scanning FOV of 140° × 16° and a divergence angle of 0.725° × 0.056°. A peak SLSR of 27.15 dB is obtained at 0°, with an average SLSR of 20 dB over the full 140° FOV, which paves the way for full-field blind zone free scanning in autonomous driving applications. Furthermore, we experimentally validated the full-field ranging capability of the OPA transceiver in a frequency-modulated continuous wave (FMCW) system, achieving a long-range detection up to 50 meters while demonstrating its performance in 3D imaging applications.