Dual window processing schemes for spectroscopic optical coherence tomography (OCT) and fourier domain low coherence interferometry

摘要

Current apparatuses and methods for analysis of spectroscopic optical coherence tomography (SOCT) signals suffer from an inherent tradeoff between time (depth) and frequency (wavelength) resolution. In one non-limiting embodiment, multiple or dual window (DW) apparatuses and methods for reconstructing time-frequency distributions (TFDs) that applies two windows that independently determine the optical and temporal resolution is provided. For example, optical resolution may relate to scattering information about a sample, and temporal resolution may be related to absorption or depth related information. The effectiveness of the apparatuses and methods is demonstrated in simulations and in processing of measured OCT signals that contain fields which vary in time and frequency. The DW technique may yield TFDs that maintain high spectral and temporal resolution and are free from the artifacts and limitations commonly observed with other processing methods.

主权项

1. A method of obtaining depth-resolved spectra of a sample for determining scattering and absorption characteristics within the sample, comprising:
emitting a beam onto a splitter, wherein the splitter splits light from the beam to produce a reference beam, and an input beam to the sample; cross-correlating the reference beam with a sample beam returned from the sample as a result of the input beam by mixing the reference beam and the returned sample beam from the sample to yield a cross-correlated profile having optical, depth-resolved information about the returned sample beam; generating a spectroscopic depth-resolved profile that includes optical properties about the sample by:
providing first one or more spectroscopic windows of the cross-correlated profile, each of the first one or more spectroscopic windows having a first width at a given center wavelength to obtain optical information about the sample for each given center wavelength;applying a Fourier transform to the optical information about the sample to recover high resolution optical information about the sample at each given center wavelength simultaneously;providing second one or more spectroscopic windows of the cross-correlated profile, each of the second one or more spectroscopic windows having a second width greater than the first width at a given center wavelength to obtain absorption information about the sample for each given center wavelength;applying a Fourier transform to the absorption information about the sample as a function of depth to recover high resolution depth information about the sample at each given center wavelength simultaneously; andco-registering the high resolution optical information and the high resolution depth information about the sample to yield a single high resolution spectroscopic optical-resolved, depth-resolved profile about the sample.