Silicon Ribbon-Based Dual-Beam Optical Phased Array with Low Crosstalk and Large FoV

Hsun-Yuan Chi,Che-Chang Chang,Wei Hong,Shih-Hsiang Hsu,Hsuan Lai

doi:10.3390/app12010505

Hsun-Yuan Chi, Che-Chang Chang + Show 3 more

Open Access

https://doi.org/10.3390/app12010505

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Abstract

In this paper, a silicon ribbon (SR)-based microstructure is developed and added to a 32-channel optical phased array (OPA) to reduce the crosstalk between the antennas of grating waveguides. The spacing between the chirped grating antennas can be as close as 600 nm to effectively improve the field of view (FoV) of the OPA in the horizontal direction to 95 degrees. This SR-based approach substantially reduces the side lobe by 10 dB, effectively suppressing the noise and increasing the main lobe by 6 dB and considerably expanding the grating length with linear energy decay. The full width at the half maximum of the light spot reaches about 0.24 degrees. The antenna sites can simultaneously be scanned vertically by bi-directional inputs, effectively increasing the FoV to 30 degrees in the vertical direction.

Highlights

Light detection and ranging (LiDAR) is one of the most promising and high-potential technologies in scanning and detection nowadays
We propose an optical phased array (OPA) structure built on an SOI chip using a waveguide array with varying line widths below the half-wavelength spacing
An silicon ribbon (SR) grating array is implemented between the chirped fishbone grating (FBG) emitting arrays for crosstalk reduction

Summary

Introduction

Light detection and ranging (LiDAR) is one of the most promising and high-potential technologies in scanning and detection nowadays. Silicon Ribbon-Based Dual-Beam Optical Phased Array with Low Crosstalk and Large FoV. Many investigations have been conducted in recent years toward the concept of “LiDAR onchip” [3,4], among which the phased optical array is demonstrated through a fiber-based 1550 nm wavelength range using silicon-based waveguides.

Results

Conclusion