Multi-channel spectral-domain optical coherence tomography using single spectrometer

Multi-channel detection is an effective way to improve data throughput of spectral-domain optical coherence tomography (SDOCT). However, current multi-channel OCT requires multiple detectors, which increases the complexity and cost of the system. We propose a novel multi-channel detection design based on a single spectrometer. Each camera pixel receives interferometric spectral signals from all the channels but with a spectral shift between two channels. This design effec-tively broadens the spectral bandwidth of each pixel, which reduces relative intensity noise (RIN) by pM times with M being the number of channels. We theoretically analyzed the noise of the proposed design under two cases: shot-noise limited and electrical noise or RIN limited. We show both theoretically and experimentally that this design can effectively improve the sensitivity, especially for electrical noise or RIN-dominated systems.

Automated summary

Multi-channel detection is an effective way to improve data throughput of spectral-domain optical coherence tomography (SDOCT). However, the current approach using multiple detectors increases system complexity and cost. We propose a novel multi-channel detection design based on a single spectrometer, which broadens the spectral bandwidth of each pixel, reducing relative intensity noise (RIN). The theoretical and experimental analysis shows that this design effectively improves sensitivity, especially for systems dominated by electrical noise or RIN.