WORKING METHOD FOR LENS HAVING DISTRIBUTION OF REFRACTIVE INDEX IN OPTICAL AXIS DIRECTION, LENS HAVING DISTRIBUTION OF REFRACTIVE INDEX IN OPTICAL AXIS DIRECTION PRODUCED BY THE METHOD, AND COLLIMATOR USING THE LENS

摘要

PROBLEM TO BE SOLVED: To provide a working method for a lens having distribution of refractive index in an optical axis direction, with which the dispersion of optical performance, especially, of spherical aberration is reduced, and to provide a collimator, with which satisfactory optical performance can be provided by reducing an insertion loss even when an inter-lens distance is changed over a wide range.;SOLUTION: In a working method for a lens having distribution of refractive index in an optical axis direction, the lens having spherical surface of a curvature radius (r) on one end face side is formed from a substrate 11 (figure 1 (a)) having the distribution of refractive index different depending on depth positions in the direction of optical axis from one end face 11a, and the side of one end face 11a for each of samples 18₁-18₅ produced from the substrate 11 is ground or polished so that each of stock removal ΔZ₁-ΔZ₅ from one end face 11a can be different step by step. The surface refractive index of the end face of each sample produced by grinding is measured. On the basis of this measured result, the refractive index distribution of the substrate 11 is obtained.;COPYRIGHT: (C)2002,JPO