Patent ID: 7612323

Claim:
A method for adjusting the position of a condensing spot relative to a near-field light generating minute structure formed near the condensing position of an optical element, comprising the steps of: scanning a surface of the optical element perpendicular to an optical axis by a light beam; detecting the position of position detecting minute structures formed outside of the near-field light generating minute structure; and detecting the position of the near-field light generating minute structure based on a change of reflectance of incident light, the near-field light generating minute structure, which includes: a first area configured to provide a high reflectance of the incident light; and an opening within the first area configured to provide a slightly lower reflectance of the incident light than is provided by the first area; wherein the change of reflectance of the incident light from the position detecting minute structures to the first area, and from the first area to the opening, facilitates detecting the position of the near-field light generating minute structure.