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Nowadays in ophthalmologic practice several commercial instruments are available to image patient retinas in vivo.
Many modern fundus cameras and confocal scanning laser ophthalmoscopes allow acquisition of two dimensional en
face images of the retina with both back reflected as well as fluorescent light. Additionally, optical coherence
tomography systems allow non-invasive probing of three-dimensional retinal morphology. For all of these instruments
the available lateral resolution is limited by optical quality of the human eye used as the imaging objective. To improve
lateral resolution and achieve diffraction-limited imaging, adaptive optics (AO) can be implemented with any of these
imaging systems to correct both static and dynamic aberrations inherent in human eyes. Most of the wavefront correctors
used previously in AO systems have limited dynamic range and an insufficient number of actuators to achieve
diffraction-limited correction of most human eyes. Thus, additional corrections were necessary, either by trial lenses or
additional deformable mirrors (DMs). The UC Davis AO flood-illuminated fundus camera system described in this
paper has been previously used to acquire in vivo images of the photoreceptor mosaic and for psychophysical studies on
normal and diseased retinas. These results were acquired using a DM manufactured by Litton ITEK (DM109), which has
109 actuators arranged in a hexagonal array below a continuous front-surface mirror. It has an approximate surface
actuator stroke of ±2μm. Here we present results with a new hi-speed magnetic DM manufactured by ALPAO (DM97,
voice coil technology), which has 97 actuators and similar inter-actuator stroke (>3μm, mirror surface) but much higher
low-order aberration correction (defocus stroke of at least ±30μm) than the previous one. In this paper we report results
of testing performance of the ALPAO DM for the correction of human eye aberrations. Additionally changes made to
our AO flood illuminated system are presented along with images of the model eye retina and in-vivo human retina
acquired with this system.
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