Eyeglass Lens Bevel Correction for Frame Fit and Appearance
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Solution Overview
Problem
Existing eyeglass lens processing technologies face challenges in simultaneously improving the appearance of eyeglasses and ensuring easy lens fitting to frames, as they either compromise on appearance or fail to match the groove or protrusion in the frame with the bevel or groove formed in the lens.
Innovation Solution
An eyeglass lens processing apparatus that includes a lens holding unit, a lens shape measuring unit, and processing units, which generates bevel data by acquiring frame shape data and lens edge position data to calculate a temporary bevel position that matches the frame's groove shape, and then corrects this position to ensure optimal fitting and appearance by adjusting the bevel's curve value within predetermined thresholds.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If the bevel position is set based on lens shape (edge thickness) to improve appearance, then the appearance of eyeglass is improved, but the bevel may not match the groove or protrusion in the frame making lens fitting difficult
Solution Approach 1:
The system performs preliminary actions by first calculating a provisional bevel locus based on the frame curve, then determining corrected bevel apex positions at nose-side and ear-side edge positions, and finally calculating the corrected bevel locus. This multi-step preliminary processing ensures both appearance improvement and frame compatibility before actual bevel formation
Solution Approach 2:
The system changes parameters by adjusting the bevel apex position from the provisional location to corrected positions at nose-side and ear-side edges, and modifies the bevel locus curve values to match the frame groove shape while maintaining appearance quality within predetermined thresholds
2Ease of operation
If the bevel position is set to match the frame shape for easy fitting, then the lens is easily fit to the frame, but the appearance of eyeglass becomes worse
Solution Approach 1:
The system optimizes parameters by adjusting the bevel apex position and bevel locus curve values within predetermined thresholds to achieve the best balance between frame compatibility and appearance quality
Solution Approach 2:
The system uses feedback by comparing the provisional bevel locus with the frame groove shape and adjusting the bevel apex positions and locus curve values accordingly to achieve optimal matching while maintaining appearance standards
3Shape
If the bevel position is changed significantly to improve appearance, then the appearance of eyeglass is improved, but the bevel may depart from the edge face of the lens making fitting impossible
Solution Approach 1:
The system controls parameter changes by adjusting the bevel apex position and bevel locus curve values within predetermined thresholds that ensure the bevel remains within the edge thickness of the lens while still achieving appearance improvement
Solution Approach 2:
The system applies dynamics by allowing flexible adjustment of bevel parameters within defined ranges (predetermined thresholds) to optimize both appearance and fitting while maintaining reliability that the bevel stays within edge thickness
Data Source
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AI summary
An eyeglass lens processing apparatus configured to form, on a peripheral edge of a lens, a bevel or a groove for fitting the lens to a frame of an eyeglass, includes: a data calculating unit for calculating data of the bevel or the groove to be formed on the peripheral edge of the lens based on frame shape data of the frame or demonstration lens shape data which is shape data of a demonstration lens having the bevel or the groove fitted to the shape of the frame; and a correction unit for approximating a front-side foot width, which is a width between a position of the bevel or the groove to be formed on the lens and a position of a front edge of the lens, to a target value by correcting the data of the bevel or the groove calculated by the data calculating unit.