| 摘要 |
PROBLEM TO BE SOLVED: To improve the accuracy and stability of the power of a lens, and to manufacture a lens undistorted over the whole lens surface by minimizing the deformation of the lens due to the thermal contraction of an alloy even in the lens having a high refractive index. SOLUTION: This lens holder 7 is composed of a fixture 13 and the alloy 16, and is constituted for holding the convex surface 5a of the lens 5. When supplying the melting alloy 16, a clearance for supplying the alloy 16 is formed between the lens 5 and the fixture 13 by holding the convex surface outer peripheral part of the lens 5 by surrounding the circumference of the fixture 13 by a blocking ring 14. The fixture 13 is composed of a plurality of kinds of fixtures having different heights selected so as to correspond to the kind of the lens 5 different in a diameter and the base curve of the convex surface 5a, and the blocking ring 14 is similarly composed of a plurality of kinds of blocking rings different in inner diameters and heights selected so as to correspond to the kind of a lens different in a diameter and the base curve of the convex surface. Each of heights of the fixture 13 and the blocking ring 14 is set so that the central thickness of the alloy 16 falls within a range of 1.90 to 3.00 mm. COPYRIGHT: (C)2004,JPO
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