OPTICAL PICKUP

摘要

PROBLEM TO BE SOLVED: To reduce the diameter of a main robe and to suppress the increase in strength of a side robe by optimizing the optical characteristics of an attenuating body. SOLUTION: The optical strength of a region screened by a light screening body 3 for generating optical super-resolution is not made to be 0, but the light in the vicinity of an optical axis is attenuated and a part of the light is passed in this constitution. The diameter A or the thickness (a) and the transmittance T of the attenuating body 3 having the optimal values of the optical characteristics given by the following expressions. When the shape of the attenuating region by the attenuating body is circular, the values are given by (objective-lens effective diameter)×0.50.27. When the shape of the attenuating region of the light by the attenuating body has the belt shape, the values are given by (objective- lens effective diameter)×0.250.54.