Title: A Miniaturized High-Étendue Raman Spectrometer Platform for Wearable Molecular Sensing
Speaker: Adler Perotte, Chief Science and Innovation OMicer, Liom Health AG
Faculty Host: John Kymissis
Abstract
Raman spectroscopy provides direct molecular specificity, but its practical use in
biological tissue is constrained by extremely weak signal levels, scattering, fluorescence
background, and limited photon budgets. These constraints become more severe in
wearable systems, where spectrometer volume, optical throughput, spectral resolution,
power consumption, and mechanical robustness must be optimized simultaneously.
This talk describes the development of a miniaturized Raman photonics platform for
wearable, non-invasive molecular sensing, with glucose monitoring as a motivating
application. The central optical design challenge is étendue: increasing the spatial-angular
phase space accepted by the spectrometer while preserving the spectral resolution and
stability required for weak Raman measurements. We introduce a high-étendue dispersive
spectrometer architecture designed to exceed the throughput per unit volume of
conventional slit-limited dispersive spectrometers, while avoiding the conditioning and
noise penalties that can arise in reconstructive or interferometric approaches under
photon-starved biological measurement conditions.
In parallel with the miniaturized spectrometer development, benchtop Raman
measurements in human subjects demonstrate non-invasive glucose estimation without
individual user calibration, enabled by machine-learning models that extract weak
molecular signatures from high-dimensional spectra. We also discuss preliminary
extensions to additional molecular and physiological signals.
Together, these results suggest that wearable Raman sensing requires a co-designed
optical and statistical measurement system: high-étendue dispersive photonics to collect
suMicient molecular information, and machine learning to separate weak analyte-
dependent structure from biological and instrumental variability. The broader goal is a
scalable wearable platform for continuous, non-invasive molecular sensing.
Bio
Adler Perotte, MD, MA is Chief Science and Innovation OMicer at Liom Health AG, where he leads scientific strategy along with a team of experts to develop a wearable Raman spectroscopy platform for non-invasive molecular sensing, starting with glucose. His work is at the intersection of optical-system design, biomedical spectroscopy, machine learning, and clinical validation, with a focus on translating weak molecular signals from tissue into robust biomarker estimates. At Liom, he helps guide the development of machine learning as well as miniaturized photonics systems designed to preserve Raman’s molecular specificity while meeting the constraints of Liom’s product including wearable form factor, optical throughput, low power, robustness, and manufacturability.