Multi-shaping technique reduces sidelobe magnitude in optical coherence tomography

Abstract

Shaping methods that are commonly used in Fourier-domain optical coherence tomography (FD-OCT) can suppress sidelobe artifacts in the axial direction, but they typically broaden the mainlobe of the point spread function (PSF) and reduce the axial resolution. To improve OCT image quality without this tradeoff, we have developed a multi-shaping technique that reduces the axial sidelobe magnitude dramatically and achieves better axial resolution than conventional shaping methods. This technique is robust and compatible in various FD-OCT imaging systems. Testing of multi-shaping in three experimental settings shows that it reduced the axial sidelobe contribution by more than 8 dB and improved the contrast to noise by at least 30% and up to three-fold. Multi-shaping enables accurate image analysis and is potentially useful in many OCT applications.

Axial Super-Resolution Study for Optical Coherence Tomography Images Via Deep Learning

“…Improvement of hardware is expensive and timeconsuming. Digital signal or image processing methods provide alternative and relatively cheaper solutions, and some signal processing methods, such as deconvolution [8], [9], spectrum-shaping [10], [11], and spectral estimation [12], have been proposed to optimize the OCT images. Although the qualities of OCT images can be improved to a certain extent, these processing methods cannot upgrade the axial resolution beyond the theoretical limit because there is no prior knowledge.…”

Deep learning-based image enhancement in optical coherence tomography by exploiting interference fringe

“…While hardware-based enhancement techniques require expensive high-performance lasers and/or additional optical components to improve OCT images 8 – 11 , software-based approaches can achieve such enhancement with only minimal modification to the underlying system. Conventional software-based studies have proposed spectral estimation 12 and spectrum - shaping 13 for enhancing resolution, and B-scan averaging 14 and filtering-based methods 15 – 17 for suppressing noise. However, these methods often require relatively time-consuming iteration algorithms for the enhancement, introducing spurious artifacts and oversmoothing the images.…”

Multi-window approach enables two-fold improvement in OCT axial resolution with strong side-lobe suppression and improved phase sensitivity

“…Recent work by Fraser and coworkers [ 9 ] demonstrated a “multi-shaping technique” to achieve high side-lobe suppression while maintaining a narrow point-spread function (PSF). First, they created a matrix of rectangular windows with various widths, W(k,n), where n is the number of window functions.…”