PHASE-INVERTED SIDELOBE-ANNIHILATED OPTICAL COHERENCE TOMOGRAPHY

摘要

An optical coherent tomographic imaging system includes means for introducing a 180-degree phase inversion in the interference fringes, and generating a two-peak shape point spread function (PSF) in the frequency domain for the interference-based tomographic imaging system. The system further includes means for achieving sharper resolution than the diffraction-limited spectral bandwidth in the tomographic imaging system through subtracting the two-peak shape from the original Gaussian PSF. Means are provided for removing the ghost fringes in the tomographic imaging system, which is introduced by the self-interference between the different layers of the sample arm. The apparatus is configured to realize the real-time super-resolution swept-source optical coherent tomography (OCT) such that the sensitivity of the system is enhanced by suppressing the noise floor in the frequency domain, as well as removing the ghost fringes.

主权项

1. An optical coherent tomographic imaging system comprising:
a light source for generating sample surface-penetrating radiation; an interferometer with a beam splitter for splitting the radiation into reference and sample arms; the radiation from each arm being returned to the beam splitter and combined to generate an interference pattern; a detector for receiving the interference pattern; a beam scanner in the sample arm configured to direct the radiation to a plurality of different locations on a two-dimensional region of a sample surface to scan a plurality of different sites associated with each different location; a reflective phase modulator in the reference arm configured to introduce a 180-degree phase inversion in the radiation as it is reflected and returned to the beam splitter during alternate sweeps of the beam scanner; a Fourier Transform generator for generating the Fourier Transform of the interference pattern such that the sweep with the phase inversion creates a two-peak shape point spread function (PSF) in the frequency domain and the interference pattern for the sweep without the phase inversion creates a single peak Gaussian shape; and a subtraction circuit for subtracting two peak shapes from the single peak shape to affect a sharper resolution than the diffraction-limited spectral bandwidth.