公开(公告)号：GB2414813A

公开(公告)日：2005-12-07

申请号：GB0518121

申请日：2004-12-02

Applicant: KONICA MINOLTA OPTO INC

Inventor： KIMURA TOHRU

IPC: G02B5/18 ,  G02B13/00 ,  G02B13/18 ,  G02B27/42 ,  G11B7/00 ,  G11B7/1353 ,  G11B7/1369 ,  G11B7/139 ,  G11B7/1392 ,  G11B7/135

Abstract: A second diffraction structure, having an optical path length ratio w B12 between wavelength g 1 and wavelength g 2 that is different from an optical path length ratio w A12 in the above first diffraction structure, is provided in a diffraction optical element, and the difference in diffraction action between the first and second diffraction structures is used to thereby be able to control or minimize the wavelength-dependency of spherical aberration in the first diffraction structure. Therefore, it is possible to improve yield in bluish-purple laser light source mass production and reduce the production costs of a bluish-pusple laser light source and an optical pickup device.

公开(公告)号：EP2141702A4

公开(公告)日：2010-05-26

申请号：EP08740269

申请日：2008-04-11

Applicant: KONICA MINOLTA OPTO INC

Inventor： KIMURA TOHRU

IPC: G11B7/135 ,  G02B13/00 ,  G02B13/18

CPC classification number: G02B13/18 ,  G02B3/08 ,  G02B5/1895 ,  G02B27/0037 ,  G02B27/4238 ,  G02B27/4283 ,  G11B7/1275 ,  G11B7/1353 ,  G11B7/1374 ,  G11B7/13922 ,  G11B7/1395 ,  G11B2007/0006

公开(公告)号：EP1806743A4

公开(公告)日：2008-12-10

申请号：EP05795842

申请日：2005-10-20

Applicant: KONICA MINOLTA OPTO INC

Inventor： KIMURA TOHRU ,  NOMURA EIJI

IPC: G11B7/135 ,  G02B13/00 ,  G02B13/18

CPC classification number: G11B7/1374 ,  G11B7/1353 ,  G11B7/13922 ,  G11B7/13925 ,  G11B2007/0006

Abstract: An objective lens of an optical pickup for reproducing and/or recording information by condensing light to the information recording surfaces of first through third information recording media. The objective lens has a single lens structure and is used commonly for the first through third information recording media, and at least one optical plane of the objective lens is divided into at least two regions, a central region including the optical axis and a peripheral region surrounding the central region. A first diffraction structure is formed in the central region, and the objective lens condenses diffraction lights of the same order, out of the diffraction lights of first through third light beams generated in the first diffraction structure, respectively, onto the information recording surfaces of the first through third information recording media. A second diffraction structure is formed in the peripheral region, and the objective lens condenses diffraction lights of different orders, out of the diffraction lights of first and second light beams generated in the second diffraction structure, respectively, onto the information recording surfaces of the first and second information recording media.

公开(公告)号：EP1855274A4

公开(公告)日：2008-12-10

申请号：EP06712685

申请日：2006-01-31

Applicant: KONICA MINOLTA OPTO INC

Inventor： KIMURA TOHRU ,  NOMURA EIJI

IPC: G11B7/135 ,  G02B13/00 ,  G02B13/18

CPC classification number: G02B3/08 ,  G11B7/1367 ,  G11B7/1374 ,  G11B7/13922 ,  G11B2007/0006

Abstract: In an objective lens to be used for an optical pickup device, one plane of a lens having power is provided with a superposing structure wherein a first optical path difference giving structure and a second optical path difference giving structure are superposed. In the first optical path difference giving structure, a spherical aberration changes in an insufficient correction direction when a wavelength of an entering luminous flux is longer, and in the second optical path difference giving structure, the spherical aberration changes in an excess correction direction when the wavelength of the entering luminous flux is longer.

公开(公告)号：EP1734519A4

公开(公告)日：2008-08-06

申请号：EP05727514

申请日：2005-04-01

Applicant: KONICA MINOLTA OPTO INC

Inventor： KIMURA TOHRU ,  HASHIMURA JUNJI

IPC: G11B7/135 ,  G02B3/08 ,  G02B3/10 ,  G02B5/18 ,  G02B13/00 ,  G02B13/18 ,  G11B7/00 ,  G11B7/125

CPC classification number: G11B7/1374 ,  G02B3/08 ,  G02B3/10 ,  G11B7/1275 ,  G11B7/1353 ,  G11B7/1367 ,  G11B7/1378 ,  G11B7/13922 ,  G11B2007/0006 ,  G11B2007/13727

Abstract: A multi-focal object lens used in an optical pickup device having a first diffraction structure on at least one optical plane and condensing a m-order diffraction light and an n-order diffraction light (m≠n) occurring when a light flux at wavelength λ1 enters the first diffraction structure onto the information recording surfaces of two kinds of optical disks mutually different in protection layer thickness, wherein the absolute value of the difference between the spherical aberration value SAm of a wave front when the m-order diffraction light is condensed via the protection layer of an optical disk having a thicker protection layer and the spherical aberration value SAn of a wave front when the n-order diffraction light is condensed via the protection layer of an optical disk having a thicker protection layer and the absolute value of either one of the SAm and SAn are specified values, the above first diffraction structure is composed of a plurality of annular zones divided by fine step differences, and the above diffraction order m is an integer of one or larger and satisfies a specified expression.

公开(公告)号：EP2144238A4

公开(公告)日：2010-10-27

申请号：EP08740035

申请日：2008-04-08

Applicant: KONICA MINOLTA OPTO INC

Inventor： NAKAMURA KENTAROU ,  KIMURA TOHRU

IPC: G11B7/135

CPC classification number: G11B7/1353 ,  G11B7/1374 ,  G11B7/13922 ,  G11B2007/0006

公开(公告)号：EP1858012A4

公开(公告)日：2008-12-10

申请号：EP06714553

申请日：2006-02-24

Applicant: KONICA MINOLTA OPTO INC

Inventor： IKENAKA KIYONO ,  KIMURA TOHRU ,  NOMURA EIJI ,  MORI NOBUYOSHI ,  SAKAMOTO KATSUYA ,  HASHIMURA JUNJI ,  OTA KOHEI

IPC: G11B7/135 ,  G02B5/18 ,  G02B13/18

CPC classification number: G11B7/1367 ,  G11B7/1275 ,  G11B7/1353 ,  G11B7/1374 ,  G11B7/13922 ,  G11B2007/0006

Abstract: An optical pickup device comprising a first light source for outputting a first light beam, a second light source for outputting a second light beam, a third light source for outputting a third light beam, and an objective optical unit having an annular-structure first light path difference imparting structure and an annular-structure second light path difference imparting structure, wherein the magnifications of the objective optical unit when the first, second and third beams are incident to the objective optical unit are almost the same, the first light path difference imparting structure imparts a specified light path difference to the first light beam, and changes the spherical aberrations of all the first light beam, second light beam and third light beam to one of under and over directions, the second light path difference imparting structure imparts a specified light path difference to the first light beam, and changes the spherical aberration of only the second light beam out of the first light beam, second light beam and third light beam to the other direction different from the one of under and over directions.