Compact, Lightweight, and Filter-Free: An All-Si Microspectrometer Chip for Visible Light Spectroscopy

Abstract

Spectroscopic optical measurements of visible light provide important real-time information in many research and industrial settings. Conventional spectrometers are well established in this context due to their accuracy and reliability; however, they have not found widespread use in field-deployed applications due to their bulk (size and weight) and susceptibility to mechanical shock. Here we demonstrate a compact, lightweight microspectrometer chip-scale solution based on doped silicon nanophotonic elements, known as waveguide array (WGA) pixels. Each pixel is an array of 2.7 μm tall vertically oriented slab waveguides with a subwavelength array period, etched into a P-I-N-doped silicon sub..