Simultaneous Optimisation of Confocal and Non-confocal Images in an AOSLO with a Reconfigurable Aperture Pattern

Conference paper
Part of the Communications in Computer and Information Science book series (CCIS, volume 1248)


The conventional adaptive optics scanning laser ophthalmoscopy (AOSLO) arrangement is specifically designed to capture the confocal (directly backscattered) light by placing a physical pinhole conjugate to a chosen layer in the retina. This arrangement can be used to generate high contrast images of the photoreceptor mosaic by limiting the light from other retinal layers, such as the retinal pigment epithelium. However, there is growing demand for the study of different retinal features that has led to the development of different off-axis techniques to collect the non-confocal (multiply scattered) light. In this paper, we replace the physical pinhole of the AOSLO with a reconfigurable aperture to simultaneously collect the directly backscattered light, generating confocal images, as well as the multiply scattered light, generating non-confocal images. The reconfigurable aperture pattern is implemented with a digital micromirror device (DMD) and is optimised based on the information collected from Shack Hartmann wavefront sensor data. We present preliminary experimental results with a human eye to illustrate our findings.


Adaptive optics imaging Retinal imaging Non-confocal imaging Digital micromirror device 



Authors would like to acknowledge the financial support from various sources: Fight For Sight (1467/8); University of Oxford Wellcome Trust Institutional Strategic Support Fund (105605/Z/14/Z); the University of Oxford Medical Research Fund (MRF/LSV2015/2161); the EPA Cephalosporin Fund (CF 277); the John Fell Oxford University Press (OUP) Research Fund (103/786 and 151/139); The Dowager Countess Eleanor Peel Trust.


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© Springer Nature Switzerland AG 2020

Authors and Affiliations

  1. 1.University of OxfordOxfordUK
  2. 2.Newcastle UniversityNewcastleUK

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