On-chip Raman spectrometers using narrow band filter array combined with CMOS image sensors
Yeonsang Park, Un Jeong Kim, Su‐Yeon Lee, Hyochul Kim, Jineun Kim, Hyunjun Ma, Hyungbin Son, Young Zoon Yoon, Jaesoong Lee, Minsu Park, Hyuck Choo, Q.-Han Park, Young‐Geun Roh
Abstract
Recent advancements in nanotechnology raise the feasibility of a miniaturized, portable Raman spectrometer with promising applications such as material identification, food safety monitoring, and health care. Miniaturizing Raman spectrometers has remained a challenge owing to the inevitable weakness of Raman signals and the conflict between small size and spectral resolution. In this study, we present a portable mini-Raman spectrometer comprising a complementary metal–oxide semiconductor (CMOS) image sensor (CIS) integrated with an array of filter sets, a confocal probe, and a laser diode that successfully meets the miniaturization challenge. We also report successful measurement of Raman spectra using the CIS-based mini-spectrometer, measuring cyclohexane liquid, tylenol pills, and vitamin-C pills with high spectral resolution. Our mini-Raman spectrometer, which can measure Raman signals in a two-dimensional (2D) image format in a single-shot, can be embedded into commercial mobile phones and transformed into a promising Raman camera.