摘要:
An objective lens according to the present invention is provided for use in an optical pickup apparatus at least reproducing and/or recording information using a light flux with a wavelength λ1 emitted by a first light source for a first optical disc and reproducing and/or recording information using a light flux with a wavelength λ2 emitted by a second light source for a second optical disc. The objective lens includes a diffractive structure formed on the at least one optical surface of the objective lens. The light fluxes with the wavelengths λ1 and λ2 enter the objective lens, an optical system magnifications m1 and m2 of the objective lens respectively for the light fluxes with wavelengths λ1 and λ2 have different signs and values from each other, and the diffractive structure has a positive diffractive action.
摘要:
An optical pickup device includes a light source emitting a light beam having a wavelength within a range of 390 nm to 420 nm and an optical element to perform recording and/or reproducing of information of an optical disk having a protective substrate thickness d1 mm using the first light beam from the first light source, wherein the optical element is made of a mixed material produced by dispersing particles into a resin, a sign of a refractive index change Δn2/Δt of the particles owing to a temperature change is opposite to a sign of a refractive index change Δn1/Δt of the resin owing to a temperature change, or an absolute value of the refractive index change Δn2/Δt is smaller than an absolute value of the refractive index change Δn1/Δt.
摘要:
An optical pickup device includes an objective optical element through which light fluxes respectively with wavelengths λ1, λ2 and λ3 pass and a divergent angle-converting element that causes light fluxes respectively with wavelengths λ1, λ2 and λ3 pass through and causes at least q light flux with wavelength λ1 to emerge as a parallel light. A position of the divergent angle-converting element in the optical axis direction varies in the case of using the optical pickup apparatus depending on the occasion when a light flux with wavelength λ1 or λ2 passes through or on the occasion when a light flux with wavelength λ3 passes through.
摘要:
An optical pick-up apparatus comprising: first, second and third light sources for recording and/or reproducing respectively first, second and third optical information recording material; an objective optical element having a diffractive structure on an optical surface of the objective lens, wherein a diffraction efficiency E1 of a first primary diffractive ray is not less than 90%, a diffraction order n1 of the first primary diffractive ray is an odd number, and an output power PW3, which is an output power of the third light source when the third light source emits the third light flux, is emitted is greater than an output power PW1, which is an output power of the first light source when the first light source emits the first light flux.
摘要:
An objective optical element for use in an optical pickup apparatus, includes an objective lens to converge the light flux emitted from the first and second light sources; and an optical functional surface including a common region and an exclusive region. When a first optical information medium is used, a sine condition unsatisfied-amount whose value is maximum exists on the common region. The following formula is satisfied: 0.5≦COMA2/COMA1≦1.0 where COMA1 is a coma aberration (λ1 rms) when a light flux goes slantingly to be incident with a view angle of 1° onto the objective optical element when the first optical information medium is used, and COMA2 is a coma aberration (λ2 rms) when a light flux goes slantingly to be incident with a view angle of 1° onto the objective optical element when the second optical information medium is used.
摘要:
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 λ1 (380 nm≦λ1≦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.
摘要:
An optical pickup apparatus for recording and/or reproducing information for an optical information recording medium, comprising a light converging optical system including a coupling lens and an objective lens, wherein a first diffraction structure is installed on the objective lens, and a second diffraction structure is arranged on the coupling lens, whereby spherical aberration caused by change of ambient temperature is reduced by giving a condition to reduce the number of areas formed in a ring-shaped of the diffractive structure.
摘要:
The present invention provides an optical pickup apparatus including: a first light source; a second light source; and a light-converging optical system including a coupling lens and an objective lens. The coupling lens includes a first diffractive structure. The optical pickup apparatus satisfies a predetermined condition according to the chromatic aberration, focal length, and dispersion of the material.
摘要:
The present invention provides an optical pickup apparatus including a first light source, a second light source, a third light source, and a light-converging optical system including an objective lens. The objective lens includes at least one optical surface with a diffractive structure. The diffractive structure includes a plurality of ring shaped zones. Each of the ring shaped zones is concentrically arranged around an optical axis and includes a step difference extending along the optical axis. In the objective lens, the predetermined conditions according to an average of step differences of the plurality of ring shaped zones, a focal length, a magnification, and the Abbe number, are satisfied.