초록 ▼

A granular body, from which an article having a nonuniform refractive index may be formed, has grains of two substances which have different refractive indicies in a geometric distribution in the granular body corresponding to the geometric distribution of the substances required for the nonuniform

A granular body, from which an article having a nonuniform refractive index may be formed, has grains of two substances which have different refractive indicies in a geometric distribution in the granular body corresponding to the geometric distribution of the substances required for the nonuniform refractive index of the article and a way of shape-stabilizing the granular body. A method of making the granular body comprises controllably feeding the grains into the geometric distribution in the granular body and shape-stabilizing it. Preferably the granular body is compressed into a porous compact which holds itself together and is treated with a gas to achieve desired optic properties in the article.

대표청구항 ▼

A method for manufacturing an elongate light transmissive optical glass body having a central axis and a cylindrical circumference, said elongate body having a non-uniform refractive index which decreases radially between said axis and said circumference, said method comprising the following steps:

A method for manufacturing an elongate light transmissive optical glass body having a central axis and a cylindrical circumference, said elongate body having a non-uniform refractive index which decreases radially between said axis and said circumference, said method comprising the following steps: storing grains of at least two substances which yield glass having different refractive indices, in a respective at least two hoppers, said grains having diameters in the range of 0.01 m1 mm, mixing said grains in a desired proportion which will provide said non-uniform refractive index by controlled feeding into a common feed line having a pouring spout for pouring the mixed grains therefrom, pouring said grains onto a support while rotating said support about a vertical axis of rotation, moving said pouring spout radially between said vertical axis and means defining a circumference at a fixed radius from said axis while rotating said support, moving said pouring spout vertically relative to said support while rotating said support, pouring said grains from said spout during at least one of moving said spout radially and moving said spout vertically, thereby forming a cylindrical granular body having an axis coincident with said axis of rotation, and heat fusing the granular body to form said light transmissive cylindrical glass body.