Abstract: An improved visual acuity tester is disclosed that is adapted both to measure the visual acuity of a patient and to function as an integral optical prescription calculator. The visual acuity tester essentially includes a display monitor for displaying visual acuity targets, electronic means for generating a plurality of visual acuity targets to be displayed on the monitor, and a hand-held remote control unit provided with a display unit and a keyboard coupled to the electronic means for controlling the display on the monitor and for performing prescription calculations. The visual acuity targets are created by toggling on/off the electronic means when horizontally scanning the lead lines of screen memories of the targets. Preferably, the electronic means includes a dynamic memory having two screens of memory: an active screen and an inactive screen.

Abstract: A visual function tester with binocular vision testing capabilities is disclosed, which includes a video display monitor and optical means, such as stereo vision glasses, to control the patient's viewing of the display. The opening and closing of the apertures of the glasses is synchronized to the display of a variety of visual acuity images. Certain images are made visible to each eye but not visible to the other, and certain images are displayed such that they appear out of the plane of the images. Methods for use of the apparatus are also disclosed.

Abstract: A brightness acuity tester to assess functional visual acuity in bright light conditions and to test for recovery of visual activity after photostressing the retina is disclosed. The tester essentially comprises a device closed in one direction and open in an opposite direction, an aperture provided in the device, a source of illumination mounted within the device, a plug designed removably to be positioned in the aperture to seal the same, and a power source coupled to the source of illumination via a switch. Preferably, the source of illumination is provided with anintensity control and the power source with a voltage regulator. Preferably, the device comprises a reflector having diffusely reflecting characteristics. Preferably, the power source is a battery, making the tester a hand-held one.

Abstract: In an ophthalmic refractor system for determining cylinder power and direction of axis for visual correction, cylinder axis orientation based upon corrective cylinder power in the refractor viewing path is automatically determined and introduced into the system.

Abstract: An ophthalmic refracting chart projector having rotary slide discs, the images on which are projected on a screen, having remote operating controls permitting selective showing of the slides in selectable sequence.