Rack for mounting lens for obtaining spectacle optical center, and method and apparatus for producing lens

Abstract

A method and device to obtain the optical center, mount the lens holder and produce lens, where the prism amount and the like values are measured at a position A0 on the optical surface of an uncut lens and a position for calculation of the optical center A1 is obtained by calculation. When the distance between A0 and A1 is equal to a specific value or smaller than the specific value, A0 is temporarily decided as the blocking position and A1 is decided as the optical center. When the distance exceeds the specific value, the position for the measurement of the prism amount and the like is changed to A1 and the second position for calculation of the optical center A2 is obtained by calculation similarly in accordance with an equation using the values obtained by the measurements. By conducting similar steps, the optical center is decided and the position of the blocking is temporarily decided. It is examined whether a processing interference takes place at the temporarily decided position of the blocking. When the absence of the processing interference is confirmed, the blocking is conducted. When the processing interference is estimated to take place, a position without the processing interference is selected from the positions obtained as above and the blocking is conducted at the selected position.

Description

technical field [0001] The invention relates to a method for obtaining the position of the optical center of a spectacle lens, a method for mounting a lens holder of a spectacle lens to an uncut lens, said lens holder being such a jig as a tool for grinding the edge of a spectacle lens In the process, the rotation center axis of the uncut lens is previously installed on the uncut lens, and the present invention also relates to an apparatus for installing the lens holder on the uncut lens. Background technique [0002] Glasses are formed by machining an uncut lens (usually a so-called round lens having a circular shape) into a shape that matches the shape of a spectacle frame and fitting the cut lens into the frame. In order to form spectacles, it is necessary to design them so that they are selected according to the prescription data (diopter, cylinder diopter, distance between right eye and left eye, and other similar data) of the eye of the person to wear the spectacles. ...

AI Technical Summary

Problems solved by technology

[0007] However, it is very complicated and difficult to visually measure the prism power with a lens tester at a position considered to be close to the optical center and find the position indicating that the prism power is zero

Also, the exact position of the optical center cannot always be found

The method of obtaining the position of the optical center by measuring the obtained prism power according to a specific equation has the problem that the accuracy depends on the measured position

When the frame has a vertical dimension smaller than a certain value and the lens holder is installed at the optical center, processing interference occurs because a part of the outer edge of the lens holder is outside the shape of the frame (the shape formed by processing), so it is impossible to perform deal with

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