Astigmatism optimizing method of progressive multifocal lens for eyes

Abstract

The invention relates to an astigmatism optimizing method of a progressive multifocal lens for eyes. In the astigmatism optimizing method, 80 percent of area of a profile of the progressive multifocal lens or a part of the area is selected as an astigmatism optimizing area on the basis of the initial rise distributed data of the obtained profile of the progressive multifocal lens for eyes according to the prior art, wherein the astigmatism value of the 80 percent of area is larger than a light increasing amount. The astigmatism optimizing method of the progressive multifocal lens for eyes comprises the following steps of: subtracting spherical rise distribution taking the average value of the focal power of the area as the focal power from the initial rise data distribution of the area toobtain the data distribution of the rise difference of two cambers; smoothing the data distribution of the rise difference of the two cambers by adopting an average curvature flow; and pulsing an obtained result and the spherical rise distribution to obtain the rise distribution data of the profile of the lens subjected to astigmatism optimization. The invention can effectively reduce the maximumastigmatism of the surface of the progressive multifocal lens for eyes through optimizing step processing; in addition, the refraction capacity of an effective visual area is basically unchanged.

Description

technical field [0001] The invention relates to an ophthalmic lens technology, in particular to a processing method for reducing the astigmatism of a progressive multifocal ophthalmic lens. Background technique [0002] Progressive multifocal ophthalmic lenses can meet the needs of distance vision and near vision at the same time, and avoid the defects of bifocal lenses such as visual breakage when switching between distance vision and near vision. Therefore, the application of progressive multifocal ophthalmic lenses is becoming more and more extensive. See attached figure 1 , The surface of the progressive multifocal ophthalmic lens is divided into a distance zone 1, an intermediate transition zone 2, a near zone 3 and an astigmatism zone 4. Far vision zone: the wide area located in the upper half of the progressive multifocal ophthalmic lens, which corrects the distance vision ability when the human eye is in a relaxed state of vision, providing a clear and wide field of...

AI Technical Summary

Problems solved by technology

This method tends to have large astigmatism in the peripheral astigmatism zone, and excessive astigmatism on the lens can hinder the visual comfort of the lens wearer

If the initial design parameters are changed, the optical properties of the areas on the lens that already meet the requirements will be deteriorated

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