Open AccessDigital micromirror device based ophthalmoscope with concentric circle scanning
Author(s) -
Mathi Damodaran,
Kari V. Vienola,
Boy Braaf,
Koenraad A. Vermeer,
Johannes F. de Boer
Publication year - 2017
Publication title -
biomedical optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.362
H-Index - 86
ISSN - 2156-7085
DOI - 10.1364/boe.8.002766
Subject(s) - digital micromirror device , optics , concentric , aperture (computer memory) , image quality , signal to noise ratio (imaging) , field of view , digital imaging , numerical aperture , contrast to noise ratio , materials science , physics , computer science , image processing , computer vision , digital image , wavelength , geometry , mathematics , acoustics , image (mathematics)
Retinal imaging is demonstrated using a novel scanning light ophthalmoscope based on a digital micromirror device with 810 nm illumination. Concentric circles were used as scan patterns, which facilitated fixation by a human subject for imaging. An annular illumination was implemented in the system to reduce the background caused by corneal reflections and thereby to enhance the signal-to-noise ratio. A 1.9-fold increase in the signal-to-noise ratio was found by using an annular illumination aperture compared to a circular illumination aperture, resulting in a 5-fold increase in imaging speed and a better signal-to-noise ratio compared to our previous system. We tested the imaging performance of our system by performing non-mydriatic imaging on two subjects at a speed of 7 Hz with a maximum 20° (diameter) field of view. The images were shot noise limited and clearly show various anatomical features of the retina with high contrast.