Abstract: An objective optical system for use in an optical pickup apparatus for converging first and second parallel light fluxes includes: a first lens group having a phase structure; and a second lens group, wherein the first lens group and the second lens group are arranged in the objective optical system in this order from a longer conjugate distance side of the objective optical system, and a wavefront aberration of the first lens group WL1?1, a wavefront aberration of the second lens group WL2?1, a magnification of the second lens group M, a wavefront aberration of the second lens group WL2?2, a wavefront aberration of the objective optical system WOBJ?2 are satisfy predescribed expressions.

Abstract: An optical pickup apparatus for conducting recording and/or reproducing information of an optical information recording medium, comprises a light source; a converging optical system having an objective lens; and a photo-detector. The converging optical system comprises a plastic lens and a spherical aberration deviation correcting element to correct deviation of a spherical aberration of the converging optical system. A numerical aperature of the objective lens at an image-side is 0.65 or more.

Abstract: The present invention relates to a coupling optical system, an optical element, and an optical pickup apparatus. A coupling optical system is provided for use in an optical pickup apparatus and is arranged between a light source and an objective lens of the optical pickup apparatus. The coupling optical system includes: a first optical element with a power; and a second optical element with a positive power. The first optical element includes an optical surface, an out-effective-aperture section surrounding the optical surface, and a light-reduction structure arranged on the out-effective-aperture section. When a non-parallel light flux emitted from the light source enters into the out-effective-aperture section, the light-reduction structure reduces a light flux to be emitted from the second optical element in a direction getting closer to an optical axis of the second optical element.

Abstract: An optical system for use in an optical pickup device for recording and/or reproducing information on an optical recording media, the optical system having an optical axis and comprising: an objective system for converging a light beam emitted from a light source on the optical recording media; an optical aberration correcting element comprising two lenses arranged on an optical path between the light source and the objective system and having an adjustable distance in the direction of the optical axis, the optical aberration correcting element comprising a ring-shaped phase structure formed in at least one lens surface of the optical aberration correcting element, and wherein the ring shaped phase structure is non-periodic and comprises a plurality of concentric ring surfaces k (k=1 . . . N), and each of the ring surfaces has a step in the direction of the optical axis between the adjacent ring surface.

Abstract: An optical pickup apparatus includes first and second light sources; an objective lens; a spherical aberration correcting optical unit; and a chromatic aberration correcting optical element which includes a diffractive surface on at least one optical surface of the chromatic aberration correcting optical element such that a diffractive structure which is constructed by a plurality of ring-shaped zones separated by fine steps is formed on the diffractive surface, wherein the depth of steps along an optical axis is designed so that n2, which is a diffraction order of a diffracted ray having a largest diffraction efficiency among diffracted rays caused when the second light flux enters into the diffractive structure, is a lower order than n1, which is a diffraction order of a diffracted ray having a largest diffraction efficiency among diffracted light rays caused when the second first light flux enters into the diffractive structure.

Abstract: An objective lens, comprises a first diffractive structure having plural concentric ring-shaped zones. A n1-th order diffracted ray is converged on an information recording surface of first optical information recording medium through first protective substrate in such a way that when a wavefront aberration is measured within a first numerical aperture NA1, the RMS value of the wavefront aberration becomes 0.07?1 or less, and a n2-th order diffracted ray (n2<n1) is converged on a information recording surface of second optical information recording medium through second protective substrate in such a way that when a wavefront aberration is measured within a second numerical aperture NA2 (NA2<NA1), the RMS value of the wavefront aberration becomes 0.07?2 or less.

Abstract: A hybrid objective lens has a refractive lens and a diffractive optical element constructed by plural coaxial ring-shaped zones on at least one optical surface thereof. When n1, n2 and n3 each is a diffraction order of a diffracted ray having a maximum light amount among diffracted rays of each of first, second and third light flux having wavelength ?1, ?2 and ?3 when respective light flux comes to be incident into the diffractive structure respectively, the following formulas are satisfied: |n1|>|n2|, and |n1>|n3|, and the hybrid objective lens converges a n1-th, n2-th and n3-th order diffracted ray of the first, second and third light flux onto an information recording plane of each of the first, second ant third optical information recording medium respectively so as to form an appropriate wavefront within respective prescribed necessary image side numerical apertures.

Abstract: An optical system for use in an optical pickup apparatus comprises a first optical surface having a superposition type diffractive structure including a plurality of ring-shaped zones which are formed concentrically around an optical axis, wherein each ring-shaped zone is composed of a plurality of stepped sections stepwise, and a second optical surface having a diffractive structure including a plurality of ring-shaped zones which are formed concentrically around an optical axis, wherein each of the plurality of ring-shaped zones are divided by a stepped section to generate a diffractive light ray of diffractive order whose absolute value is not small than 1 for the light flux.

Abstract: A hybrid objective lens has a refractive lens and a diffractive optical element constructed by plural coaxial ring-shaped zones on at least one optical surface thereof. When n1, n2 and n3 each is a diffraction order of a diffracted ray having a maximum light amount among diffracted rays of each of first, second and third light flux having wavelength ?1, ?2 and ?3 when respective light flux comes to be incident into the diffractive structure respectively, the following formulas are satisfied: |n1|>|n2|, and |n1|>|n3|, and the hybrid objective lens converges a n1-th, n2-th and n3-th order diffracted ray of the first, second and third light flux onto an information recording plane of each of the first, second ant third optical information recording medium respectively so as to form an appropriate wavefront within respective prescribed necessary image side numerical apertures.

Abstract: An optical system for use in an optical pickup apparatus comprises a first optical surface having a superposition type diffractive structure including a plurality of ring-shaped zones which are formed concentrically around an optical axis, wherein each ring-shaped zone is composed of a plurality of stepped sections stepwise, and a second optical surface having a diffractive structure including a plurality of ring-shaped zones which are formed concentrically around an optical axis, wherein each of the plurality of ring-shaped zones are divided by a stepped section to generate a diffractive light ray of diffractive order whose absolute value is not small than 1 for the light flux.

Abstract: A reference voltage generation circuit generates a reference voltage. An internal voltage generation circuit generates an internal voltage on the basis of the reference voltage generated by the reference voltage generation circuit. A first trimming circuit trims the internal voltage. During trimming of the internal voltage, the first trimming circuit trims an externally supplied first target voltage in accordance with first trimming data. The first trimming circuit ends the trimming when the first target voltage meets a given condition for the reference voltage.

Abstract: An optical pickup apparatus for conducting at least recording or reproducing of information on two types of optical information recording media having protective substrates with different thicknesses, includes: a first light source for emitting a first light flux with a wavelength ?1; a first objective lens for converging the first light flux on an information recording surface of a first optical information recording medium when the optical pickup apparatus reproduces or records information for the first optical information medium; and a second objective lens for converging the first light flux on an information recording surface of a second optical information recording medium when the optical pickup apparatus reproduces or records information for the second optical information medium, wherein effective diameters of the first objective lens and the second objective lens are substantially same.

Abstract: An optical pickup apparatus includes: first-third light sources; a packaged multiple light source unit for packaging emitting points of at least two of the first-third light sources in one housing; an objective optical system for converging light fluxes emitted by light sources onto information recording surfaces of at least three kinds of optical disks; and a magnification adjusting optical unit having an actuator and a movable lens group and being arranged in an optical path between the packaged multiple light source unit and the objective optical system, wherein the movable lens group is driven by the actuator along the optical axis so as to change a magnification of the objective optical system according to a wavelength of a light flux emitted by the packaged multiple light source unit.

Abstract: An objective lens unit for use in an optical pickup apparatus, includes a first optical element arranged opposite to the optical information recording medium; a second optical element arranged at a light source side of the first optical element opposite to the first optical element and including a ring-shaped structure in which plural ring-shaped zones are formed on at least one optical surface of the second optical element such that neighboring ring-shaped zones cause a predetermined optical path difference for incident rays; and each of the first and second optical elements having a optical functional section and a flange section formed around the optical functional section, wherein the flange section of the first optical element and the flange section of the second optical element are formed so as to fix the first and second optical elements at predetermined respective relative positions.

Abstract: 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: PD1>0 (PD1 is a diffractive power (mm?1)), PD2<0 (PD2 is a diffractive power (mm?1)) and PR2>0 (PR2 is a refractive power (mm?1) as a refractive lens).

Abstract: An optical pickup apparatus for conducting recording and/or reproducing information for a first optical information recording medium including at least a transparent protective substrate, a first information recording surface, and a second information recording surface which are laminated in this order from a light source side along an optical axis, comprising: a first light source to emit a light flux having a wavelength of ?1 (380 nm??1?450 nm); an objective lens to converge the light flux onto the first optical information recording medium; a spherical aberration correcting structure to correct a spherical aberration caused in a converged spot on the first and second information recording surfaces due to a difference in thickness between the thickness to the first information recording surface and the thickness to the second information recording surface.

Abstract: A diffractive optical element, comprises a first diffractive structure to generate n11-th order diffracted ray when a first light flux having ?1 (nm) of a wavelength comes in and to generate n21-th order diffracted ray (n11.?n21) when a second light flux having ?2 (nm) (?2>?1) comes in; and a second diffractive structure to generate n12-th order diffracted ray when the first light flux comes in and to generate n22-th order diffracted ray (n12.?n22) when the second light comes in. The diffractive optical element satisfies the following formula: ??A12???B12, where ??A12={n11·?1/(N11?1)}/{n21·?2/(N21?1)}, and ??B12={n12·?1/(N12?1)}/{n22·?2/(N22?1)}, wherein N11, N21 are refractive index of the first diffractive structure respectively for ?1 and ?2, and N12, N22 are refractive index of the second diffractive structure respectively for ?1 and ?2.

Abstract: A hybrid objective lens has a refractive lens and a diffractive optical element constructed by plural coaxial ring-shaped zones on at least one optical surface thereof. When n1, n2 and n3 each is a diffraction order of a diffracted ray having a maximum light amount among diffracted rays of each of first, second and third light flux having wavelength ?1, ?2 and ?3 when respective light flux comes to be incident into the diffractive structure respectively, the following formulas are satisfied: |n1|>|n2|, and |n1|>|n3|, and the hybrid objective lens converges a n1-th, n2-th and n3-th order diffracted ray of the first, second and third light flux onto an information recording plane of each of the first, second ant third optical information recording medium respectively so as to form an appropriate wavefront within respective prescribed necessary image side numerical apertures.

Abstract: An optical pickup device comprises a light source to emit a light flux having wavelength ?; an objective lens including at least two plastic lenses of a first plastic lens having positive refractive power and a second plastic lens having positive refractive power, wherein the first plastic lens and the second plastic lens are arranged in this order from the light source side; and an actuator to drive the objective lens; wherein the objective lens satisfies the following expression (1-1): ?0.0004<?3SA/(NA4·f·(1?m))<0.0004??(1-1) where ?3SA (?RMS) represents a rate of change of a third order spherical aberration of the objective lens when the temperature of an entire body of the objective lens uniformly changes, f (mm) represents the focal length of the objective lens for the light flux having wavelength ?, and m represents the magnification of the objective lens.

Abstract: An optical pickup apparatus for conducting recording and/or reproducing information of an optical information recording medium, comprises a light source; a converging optical system having an objective lens; and a photo-detector. The converging optical system comprises a plastic lens and a spherical aberration deviation correcting element to correct deviation of a spherical aberration of the converging optical system. A numerical aperture of the objective lens at an image-side is 0.65 or more.