Konica Corporation

Konica-Minolta Holdings, Inc.

Konica Minolta Opto, Inc.

Norikazu Arai

Shinichiro Saito

Kohei Ota

Toshiyuki Kojima

Toshihiko Kiriki

Hiroyuki Yamazaki

Yuichi Atarashi

Hiroyuki Hattori

Masaya Kobayashi

Kazuo Ishida

Shogo Yamamoto

Etsuzo Kurihara

Takashi Matsumaru

Taichiro Saito

Hiroshi Kibayashi

Koji Honda

Tohru Kimura

Yuichi Honda

Kazuhiro Wada

Tatsuji Kurogama

Makoto Banno

Yayol Eguro

Kaoru Kushida

An optical pickup apparatus for reproducing information from an optical information recording medium or for recording information onto an optical information recording medium, is provided with a first light source for emitting first light flux having a first wavelength; a second light source for emitting second light flux having a second wavelength, the first wavelength being different from the second wavelength; a converging optical system having an optical axis and a diffractive portion, and a photo detector; wherein in case that the first light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the first light flux is greater than that of any other ordered diffracted ray of the first light flux, and in case that the second light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the second light flux is greater than that of any other ordered diffracted ray of the second light flux, where n stands for an integer other than zero.

Optical pickup apparatus, recording/reproducing apparatus provided with the optical pickup apparatus, optical element, and information recording/reproducing method

A recording reproducing optical system for an optical information recording medium is provided with a light source; an objective lens; and an aberration correcting optical element provided on an optical path between the light source and the objective lens. The objective lens includes an aspherical surface and one diffractive surface on which a diffractive structure structured by a plurality of concentric ring-shaped zonal steps is formed and the objective lens is a plastic lens structured in one element in one group. The aberration correcting optical element comprises at least one plastic lens on which a diffractive structure structured by a plurality of concentric ring-shaped zonal steps is formed. The following formulas are satisfied: PD&#x3e;0 (PDis a diffractive power (mm)), PD&#x3c;0 (PDis a diffractive power (mm)) and PR&#x3e;0 (PRis a refractive power (mm) as a refractive lens).

Recording reproducing optical system, objective lens, and aberration correcting optical element

An objective optical element to be used for an optical pickup device for performing reproducing and/or recording of information to a first optical information recording medium and a second optical information recording medium by converging a light beam having a wavelength &#x3bb;(640 nm&#x2266;&#x3bb;1&#x2266;670 nm) on the first optical information recording medium having a protective substrate thickness tand by converging a light beam having a wavelength &#x3bb;(400 nm&#x2266;&#x3bb;2&#x2266;415 nm) on the second optical information recording medium having a protective substrate thickness twherein an optical system magnification msatisfies a relation of |m|&#x3c;0.01, and wherein an optical system magnification msatisfies a relation of |m|&#x3c;0.01.

Objective optical element, optical pickup device, and optical information recording and reproducing device

Optical pickup apparatus, recording/reproducing apparatus provided with the optical pickup apparatus, optical element and information recording/reproducing method

An objective lens for use in an optical pickup apparatus for conducting recording and/or reproducing information for an optical information recording medium, has a lens section shaped in an approximate circle and including a flange section; and a projecting section integrally provided to the lens section. The objective lens satisfies the following conditional formulas:0.5&#x2266;A&#x2266;2.0, 0.3A&#x2266;B&#x2266;1.7A where A is a diameter (mm) of the lens section when the lens section is viewed from an direction of an optical axis, and B is a width (mm) of the projecting section when the connecting section is viewed from the direction of the optical axis.

Optical pickup lens, molded optical component, handling method, and mold for optical component

Optical pickup appratus, recording/reproducing apparatus provided with the optical pickup apparatus, optical element, and information recording/reproducing method

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Hachioji, Japan

Norikazu Arai