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 effectively broadens the spectral bandwidth of each pixel,which reduces relative intensity noise (RIN) by ■ 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.