Abstract: A grinding wheel for V-profiling ophthalmic lenses of various diameters, powers and thicknesses has a V-shaped groove circumferentially thereabout which defines a forward V surface and a rear V surface meeting at a nadir of the groove. A rear flat surface tapers outwardly in relation to an axis of rotation of the wheel from a rear edge of the rear V surface toward a rear face of the wheel. The forward V surface is of a first grinding aggressiveness, the rear V surface is of second grinding aggressiveness greater than the first grinding aggressiveness and the rear flat surface is of third grinding aggressiveness substantially greater than the second grinding aggressiveness. In a preferred embodiment, the wheel also has a forward flat surface tapering outwardly in relation to the axis of rotation of the wheel from a forward edge of the forward V surface toward a forward face of the wheel.

Abstract: A lens projector is provided for use with a lens blocking device having an LCD target display plane disposed beneath a work surface and a tower having an upper portion extending above the work surface with a eyepiece therethrough. The lens projector includes a bracket fixed to the tower proximate the eyepiece with a light source rigidly seated on the bracket above the work surface. A viewer mounted in the eyepiece is aligned on a sight line substantially normal to and centered on the work center of the LCD target display plane. An at least partially transmissive mirror intersects the sight line and is fixed to the viewer at an angle such that light emitted from a center of the light source is reflected along the sight line toward the work surface so as to project an image of a multi-focal segment or a lens marking onto the graphic display. A shield fixed to the bracket and extending between the light source and the tower protects the tower from heat dissipated by the light source.

Abstract: A method and system for generating a lens by grinding a lens blank with a tool in a working position calls for a diamond tool to be disposed only angularly, the lens being moved in an X,Y relationship so that the relative cutting position is properly maintained. The angular disposition and X,Y relationship of the tool and the lens are pre-calculated by a computer, and the digital data thus obtained are converted to analog data for controlling a servo system. In accordance with the invention, when a certain range of curves is entered via a digital keyboard, a computation is made by computer to determine if an interference between the spindle holding the diamond tool and lens will exist, or if an interference between the lens and a chuck will exist. If an interference will exist, the chucked lens is caused to rotate around the optic axis by precisely 180.degree.

Abstract: A lens grinding machine includes a grinding tool mounted on a tool support, and a lens holder mounted in a tailstock assembly. The lens is positioned for grinding by advancing the tailstock assembly into engagement with the tool support. A push-back member carried by a housing of the tailstock assembly is actuated to displace the tailstock housing to a predetermined spacing from the tool reference axis. A dial carried by the tailstock housing and operably connected to the lens holder is rotated to bring a desired lens thickness-related value on one scale into alignment with a lens diopter-related value on an adjacent scale, whereupon a precise grinding position of the lens is attained.

Abstract: A computer-controlled lens generating arrangement (1) has a calibration gauge (14) mountable on a lens chuck (28) and moveable into a calibration position for detecting a worn or eroded condition of a tool (18). When a worn or eroded condition of tool (18) is detected, data are provided to a computer (60) which recomputes positioning data for the chuck (28), and repositioning of the chuck (28), as well as the angle of the cutting tool (18), takes place.