# High-SNR snapshot multiplex spectrometer with sub-Hadamard-S matrix coding

## TL;DR

This paper introduces a high-SNR snapshot multiplex spectrometer using sub-Hadamard-S matrix coding, which simplifies the process and achieves comparable SNR improvements to traditional Hadamard transform spectrometers.

## Contribution

The paper demonstrates for the first time that sub-Hadamard-S matrix coding can match Hadamard-S matrix performance in SNR, enabling snapshot operation without complex mask changes.

## Key findings

- Sub-Hadamard-S matrix coding achieves similar SNR improvements as Hadamard-S matrix.
- The method captures aperture light intensity and spectra in one shot.
- Experimental results confirm the effectiveness of the proposed approach.

## Abstract

We present a robust high signal-to-noise ratio (SNR) snapshot multiplex spectrometer with sub-Hadamard-S matrix coding. We demonstrated for the first time that the sub-Hadamard-S matrix coding could provide comparable SNR improvement with Hadamard-S matrix in Hadamard transform spectrometer (HTS). Normally, HTS should change the coding mask to obtain a reasonable spectrum result, causing unexpected time-consuming. An extra imaging path to collect the light intensity of the aperture is added in this paper. Both light intensity of the aperture and overlapped spectra are captured within one shot, turning Hadamard-S matrix coding into sub-Hadamard-S matrix coding. Simulations and experiments show that the proposed method could obtain comparable SNR improvement with the traditional HTS, maintaining snapshot.

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Source: https://tomesphere.com/paper/1905.07543