Speckle reduction in parallel optical coherence tomography by spatial compounding

In this paper, we propose a novel method for speckle reduction by combining spatial compounding technique with parallel Fourier-domain optical coherence tomography (FDOCT). Through a two-dimensional (2-D) CCD camera, multiple spectral interference fringes for a single lateral point are acquired with adjacent pixels in parallel detection plane simultaneously. By compounding these spatial-resolved images, we can obtain a speckle-suppressed B-scan tomogram in a single shot without sacrificing axial resolution and imaging speed. The principle of our method is demonstrated by imaging a shrimp's telson in vivo and a pearl. A signal-to-noise ratio improvement close to a factor of two was achieved by averaging four spatial-resolved FDOCT images.

► A parallel OCT for speckle reduction based on spatial compounding technique is proposed.
► Speckle reduction without sacrificing axial resolution and imaging speed is demonstrated.
► A SNR improvement close to a factor of 2 is achieved by averaging 4 spatial-resolved FDOCT images.