Abstract: An astigmatism reducing device includes an alignment tool having a bore, extending through said alignment tool, for enabling centering of said alignment tool by observation of a cornea limbus. A handle is provided for enabling placement of said alignment tool onto a cornea and sclera of an eye and a bottom curvature on the alignment tool engages and conforms to the cornea. A lid retractor including a channel adjacent said bottom curvature is provided for separating eyelids from said cornea and sclera and enabling a portion of the bottom curvature to be disposed thereunder. Tubular cornea cutter, having an outside diameter sized for insertion into the alignment tool bore means is provided for supporting at least one cutting blade for rotation within the alignment tool bore, the cutting blade being disposed with a longitudinal axis parallel to a longitudinal axis of the tubular cornea cutter.

Abstract: A visual acuity testing system includes a patient video display operated under control of a compact control unit which is located adjacent the phoropter used in acuity testing. The control unit and phoropter are located in a common operating area, thus eliminating the need to shift from one position to another to operate different devices during visual acuity testing. The control unit operates in conjunction with a graphics interface processor to provide random character generation, variable character contrast, duochrome testing, automatic timing of character display, audio prompting and generation of complex test patterns such as an astigmatic clock pattern. The use of high resolution bit-mapped and vector graphics generation techniques maximizes the quality of character displayed on the patient display unit.

Abstract: A keratometric device for attachment to a surgical microscope, the device including a housing member configured for receiving the bottom portion of the microscope therein, a screw elevator member rotatable relative to the housing member, having a screw thread about the exterior thereof and a second screw thread about the interior thereof. A ring gear is affixed to the elevator member with a knob and gear arrangement provided for rotating the elevator member. A ring lamp is provided with roller bearings engaging the external screw thread, the ring lamp providing a reference image. A prism support member is provided with outwardly extending roller bearing members for engaging the internal screw thread with a prism tray slidably movable relative to the prism support. A prism assembly is affixed to the prism tray for pivotal movement through a predetermined angle.