Abstract: The description relates to a device for facetting ophthalmic lenses with at least one facetting tool which can be engaged with a ophthalmic lens held in a clamp and with a control unit for the facetting tool in which the reference data for the radius r of the lens to be machined in relation to the angle of rotation (.phi.) are stored and which controls the operation in accordance with these reference data. The invention is especially characterized in that the control unit controls the relative movement of the tool along the z axis in such a way that the facet has a predeterminable position on the peripheral edge of the lens.

Abstract: A spectacle lens edge grinding machine includes a machine frame and at least one grinding wheel connected to the machine frame. A rotatable spectacle lens holding shaft is fastened to the machine frame. The spectacle lens holding shaft is at least radially displaceable relative to the grinding wheel. A spectacle lens is secured to the spectacle lens holding shaft for grinding with the grinding wheel. At least one abutment is provided for contacting a spectacle lens having been ground to have a desired spectacle lens contour. A transducer for measuring at least one actual value of the spectacle lens contour relative to the at least one abutment is provided. A computer for controlling the spectacle lens edge grinding machine is provided, wherein the computer includes a memory in which nominal values of the spectacle lens contour are stored. The computer compares the at least one actual value to the nominal values in order to determine a deviation from the nominal values.

Abstract: A process for measuring forward and rearward three-dimensional curves and the thickness at the circumference of a contour-ground eyeglass lens by means of a computer-controlled eyeglass lens edge grinding machine. As the corrective lens is being ground, the rotation of the corrective lens is interrupted when a measurement point is reached, and the corrective lens is shifted axially relative to the grinding disk away from the center section and toward the edges of the grinding disk until the forward and rearward edges at the circumference of the corrective lens touch the tracing device. The path or the time consumed in moving from the center section to the point of contact with the tracing device is recorded, and the measured values are stored in the computer, the shaft halves holding the corrective lens rotate further, until the next measurement point is reached, when a measurement is again taken.

Abstract: A machine for grinding the edges of a spectacle lens, including shaft halves for holding the lens therebetween, a grinding wheel for machining the periphery of the lens, a support for the template that is held by one of the shaft halves, and a measuring head that is connected to a computer and serves for measuring the position of the front and rear sides of the lens at the grinding or contact point, in the vicinity of the periphery of the grinding wheel, relative to a prescribed plane. The measuring head has a fork-like configuration, including fork legs that are disposed parallel to one another and to the prescribed plane, and are spaced from one another by a distance that is greater than the greatest width of the periphery of the lens, whereby the shaft halves with the lens, or the grinding wheel with the measuring head, carries out an oscillating back and forth movement relative to the other.