| 摘要 |
<p>A scanning laser ophthalmoscope (10, figure 1) for scanning the retina of an eye has: a laser (12); scan relay elements (14,16,18,20) which provide a two-dimensional scan from an apparent point source at a pupillary point of the eye to the retina; and a static aberration correction element 30 which has a shape defined to provide correction of aberrations of at least some of the scan relay elements and a location within the ophthalmoscope chosen to correct the aberrations. The correction element may be a transmissive phase mask of variable depth, having a topography of 130 microns, a width of 1.5 mm and a length of 12 mm. It may be integral with a window 32 on the first scanning element (14). The scan relay elements may include an ellipsoidal mirror (18) and an aspherical mirror (20). The invention further provides an aberration correction element (figure 2) and a method of determining a shape of the aberration correction element (figure 4) by constructing an appropriate power-series function.</p> |
