Fig. 1. The adaptive optics scanning laser ophthalmoscope. The six main components are labeled. Lenses are labeled L# and mirrors M#. Retinal and pupil conjugate points are labeled r and p through the optical path. FO: fiber optic light source, AP: artificial pupil, BS: beamsplitter, DM deformable mirror, HS: horizontal scanner (16kHz), VS: vertical scanner (30 Hz), LA: lenslet array, FM: flipping mirror, CP: confocal pinhole, PMT: photomultiplier tube.

Fig. 2. The two figures show the same area of retina taken with and without aberration correction with AO. In this case, the RMS wavefront error was reduced from 0.55 to 0.10 μm. The insets show the histograms of gray scales in the image.

Fig. 3. Axial sectioning. These images are from a location 4.5 degrees in the superior retina. In the left image, the focal plane is at the surface of the nerve fibers. The central image shows a slightly deeper optical section where less nerve fiber structure is seen but the blood vessel is in focus. The right image shows the image when the focal plane is at the level of the photoreceptors, which are about 300 μm deeper than the left image. The blood vessel appears dark because scattered light from its surface is blocked by the confocal pinhole. Scale bar is 100 micrometers.

Fig. 4. (2 MB) Movie sequence (30 fps) showing the flow of white blood cells though the capillaries at the edge of the foveal avascular zone (10 MB version). The capillary is the m-shaped line in the frame. The fovea is 1 degree (450 μm) up and to the right of the center of the frame. The blood cells can be seen entering the capillary at the right side and exiting the bottom edge of the frame. The frame is a registered sum of 8 sequential frames. Some resolution of the movie is lost due to compression. Longer, uncompressed movies can be found at our website [24]: www.opt.uh.edu/research/aroorda/aoslo.htm. Scale bar is 100 microns.

Figure 5. Change in photoreceptor spacing with eccentricity. The circle symbols show the cone photoreceptor spacing as a function of eccentricity from the fovea. The long-dashed line shows anatomical data from Curcio et al. 1990 and the short-dashed line show psychophysical estimations of cone spacing from Williams [25]. Our cone spacing estimates were made by measuring the average radius of Yellot’s ring [26] from the power spectrum of the images.