The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 10, 2006
Filed:
Sep. 05, 2003
Kohei Ota, Hachioji, JP;
Mitsuru Mimori, Kokubunji, JP;
Kohei Ota, Hachioji, JP;
Mitsuru Mimori, Kokubunji, JP;
Konica Corporation, Tokyo, JP;
Abstract
An objective lens to converge a light flux having a working reference wavelength λ(380 nm≦λ≦450 nm) under a working reference temperature Tonto an optical information recording medium equipped with a protective substrate having a thickness of 0.6 mm with almost no aberration. The diffractive structural section of the objective lens has a first compensating function to compensate a change amount δSAof the third-order spherical aberration component of wavefront aberration caused by a fluctuation of a working wavelength, a second compensating function to compensate a deviation δWD of a converged-light spot in an optical axis direction caused by a fluctuation of a working wavelength, and a third compensating function to compensate a change amount δSAof the third-order spherical aberration component of wavefront aberration caused by a change of a refractive index of the lens body.