Broadband Operation of an InP Optical Phased Array

Abstract

We demonstrate the broadband operation and beam calibration over 70nm tuning range of an optical phased array (OPA) fabricated in a generic InP photonic integration platform, which enables multi-wavelength OPA operation. The broadband performance was demonstrated on an 8-channel OPA, whose calibration and phase modulator characterization were executed through near-field and far-field measurements. The architecture reported here is scalable, and the results are promising for reducing the complexity of calibration and control of large-scale OPAs for their use at multiple wavelengths, for example, for spectral imaging or 2D beam steering through dispersive gratings.

Design a common optical path system for near- and far-field detection of optical phased array chips

“…Pixels A and B capture most of the energy of the two neighboring point sources, pixel C accounts for about 30% of their intensity, and the contrast between the two neighboring pixels is close to 0.53 according to Eq. (10). It means that A and B can be easily identified as two bright spots:…”

“…The contrast between two neighboring pixels can be calculated by Eq. (10), where I 1 and I 2 represent the intensity values of the target pixel.…”

“…In recent years, there have been significant advancements in integrated photonics chips for free-space optical communication, especially in the field of optical phased array (OPA), which exhibits immense potential for applications in light detection and ranging (LiDAR) 1 . After the chips are fabricated, researchers typically employ Fourier optical systems, 2 – 10 mechanical spatial scanning systems, 11 – 13 and hybrid detection systems combined with precision mechanical structures 14 – 16 to achieve near- and far-field detection of OPA chips. Calibration and phase modulator characterization can be accomplished through near- and far-field measurements on the OPA chips.…”

“…When using a Fourier optical system to detect the near- and far-field of an OPA chip, a set of lenses needs to be added or removed to switch between near-field and far-field detection modes, 2 – 10 which is tedious for researchers during practical testing. In Refs.…”

Flexible and scalable automation development tool for large-scale photonic integrated circuit design

“…Wang et al 5 proposed efficient line beam scanning based on a hybrid optical phased array rendering flexible field-of-views. Gagino et al 6 proposed broadband operation of an InP optical phased array. Yue et al 7 proposed integrated lithium niobate optical phased array for two-dimensional beam steering.…”