title: Joint aperture detection for speckle reduction and increased collection efficiency in ophthalmic MHz OCT.
abstract: Joint-aperture optical coherence tomography (JA-OCT) is an angle-resolved OCT method, in which illumination from an active channel is simultaneously probed by several passive channels. JA-OCT increases the collection efficiency and effective sensitivity of the OCT system without increasing the power on the sample. Additionally, JA-OCT provides angular scattering information about the sample in a single acquisition, so the OCT imaging speed is not reduced. Thus, JA-OCT is especially suitable for ultra high speed in-vivo imaging. JA-OCT is compared to other angle-resolved techniques, and the relation between joint aperture imaging, adaptive optics, coherent and incoherent compounding is discussed. We present angle-resolved imaging of the human retina at an axial scan rate of 1.68 MHz, and demonstrate the benefits of JA-OCT: Speckle reduction, signal increase and suppression of specular and parasitic reflections. Moreover, in the future JA-OCT may allow for the reconstruction of the full Doppler vector and tissue discrimination by analysis of the angular scattering dependence.
authors.affiliation: Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München, Oettingenstr. 67, 80538 Munich, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Klein
authors.forename: Raphael
authors.initials: R
authors.lastname: André
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wieser
authors.forename: Tom
authors.initials: T
authors.lastname: Pfeiffer
authors.forename: Robert
authors.initials: R
authors.lastname: Huber
keywords: (030.6140) Speckle; (120.3890) Medical optics instrumentation; (170.3880) Medical and biological imaging; (170.4500) Optical coherence tomography