OPTICAL ELEMENT, MANUFACTURING METHOD OF OPTICAL ELEMENT AND OPTICAL PICKUP APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide an optical element by which a pickup optical system having excellent optical performance and stable quality can be easily obtained and to provide a manufacturing method of the optical element and an optical pickup apparatus.

SOLUTION: A mark for showing an astigmatic direction is given onto the optical element in which an outside diameter is ≤5mm and a minimum cross sectional area A (mm2) at a boundary part between an outside diameter part and a gate part of the optical element is within an extent of 0.1≤A<0.4. When incorporated in the pickup apparatus, the optical element is incorporated at a position of an optimal angle by being fitted to the mark.

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