REPOSITORY
THE NICOLAUS COPERNICUS UNIVERSITY
IN TORUŃ
is an institutional repository of Nicolaus Copernicus University in Toruń. The task of the Repository is to promote scientific achievements and research conducted at NCU and to support teaching.
Recent Submissions
2-fold resolution increase and all-depth linearization using a neural network
(SPIE, 2023-08-11) Maliszewski, Krzysztof A.; Kolenderska, Sylwia M.
A neural network is proposed as a much better performing alternative to Fourier transformation. It processes raw OCT spectra into A-scans with twice better nominal axial resolution which remains intact at all depths even for an uncalibrated
spectrometer and uncompensated chromatic dispersion.
Simultaneous spectral calibration and dispersion compensation using a thin piece of glass
(SPIE, 2023-08-11) Kolenderska, Sylwia M.; Maliszewski, Krzysztof A.
The behavior of the signal elements in a quantum-mimic OCT is modelled to provide coefficients for simultaneous spectral calibration and dispersion compensation. The method allows to obtain the correction vectors based on a single spectrum and in an almost fully automatic way.
Order-specific removal of nonlinearity from Optical Coherence Tomography signals
(SPIE, 2024-06-20) Maliszewski, Krzysztof A.; Vetrova, Varvara; Kolenderska, Sylwia M.
We present two neural networks: one capable of processing a raw spectrum into an A-scan with the second-order nonlinearity removed and another for processing a raw spectrum into an A-scan with the third-order nonlinearity removed. An algorithm is also proposed to enable to use these networks in a sequence for removal of both nonlinearities. The presented approaches allow for either independent switching off of each order or the simultaneous removal of all orders, offering a tool for analysing the effects of each nonlinearity order individually or simply for performing all-depth, blind OCT data linearisation.
Advantages and limitations of using positively frequency correlated light in quantum optical coherence tomography
(SPIE, 2024-06-06) de Brito, Crislane; Kolenderska, Sylwia M.; Kolenderski, Piotr
Spontaneous-Parametric-Down-Conversion-produced photons, which are positively correlated in frequency, possess properties favorable in the context of Fourier-domain Quantum Optical Coherence Tomography (Q-OCT). These include the ease of generation and a high number of anti-diagonals needed for efficient artefact removal. On the other hand, a small diagonal width leads to a reduced axial resolution of the resultant images. The spectral characteristics of such light is analyzed both theoretically and experimentally and its validity for Q-OCT imaging discussed.
Computationally enhanced, quantum-optical ways of achieving axial super-resolution in Optical Coherence Tomography
(SPIE, 2024-03-13) Kolenderska, Sylwia M.
Mechanisms enabling axial super-resolution in OCT are identified and described based on the available research in this
area. The limitations of using each mechanisms are discussed