摘要:
In order to provide an optical pickup apparatus that has a relatively simple configuration and that can carry out recording and/or reproduction of information in a s compatible manner for different optical information storage medium, the optical surface of the first objective lens OBJ1 is formed only by a refracting surface, and hence it is possible to form it at a low cost even if it is made of glass. In addition, said first objective lens OBJ1 can be designed by optimizing it for the first light flux with the wavelength λ1 and the protective substrate t1 of said first optical disk OD1. On the other hand, while the second objective lens OBJ2 is used commonly for both the first light flux with a wavelength λ1 and the second light flux with a wavelength λ2, when the protective substrate t2 of the second optical disk OD2 and the protective substrate t3 of the third optical disk OD3 are the same, there is no need to consider the difference in the thickness of the protective substrate, and hence the design is easy and it is possible to produce at a low cost.
摘要:
An optical pickup device wherein at least a high density disc such as HD-DVD is compatible with DVD, and securing an amount of light is compatible with correction of chromatic aberration. An a correcting element representing an optical system used for the aforementioned optical pickup device.
摘要:
An objective lens for an optical pickup apparatus includes: one optical surface in an aspherical shape including a central area for converging the first and second light fluxes having a first area and the second area, and a peripheral area for converging the first light flux. The central area includes a first diffractive structure. The first diffractive structure faces an outer side of the objective lens in the first area and faces an inner side of the objective lens in the second area. The peripheral area is an optical surface which makes a light flux passing through the peripheral area reach to a position apart from the optical axis on an information recording surface of the second optical information recording medium when the optical pickup apparatus records or reproduces information on the second optical information recording medium using the second light flux.
摘要:
An optical system has an optical functional surface including a common region used for conducting information recording and/or reproducing for both of a first optical information recording medium and a second optical information recording medium. The common region comprises a refractive surface of an imaginary basic aspherical surface and a optical path difference providing structure in which plural ring-shapes zones are separated around the center of an optical axis and neighboring ring-shaped zones are displaced to each other in a direction of an optical axis so as to cause an optical path difference obtained by multiplying a predetermined wavelength λs (λ1
摘要:
A light flux from the first light source forms a converged spot on first optical information recording medium by only a refraction action of the aspheric surface, or by a combination of the refraction action and an optical action given by at least one of the first phase structure and the second phase structure, a light flux from the second light source forms a converged spot on second optical recording medium by a combination of a refraction action of the aspheric surface and an optical action given by at least one of the first phase structure and the second phase structure, and a light flux from the third light source forms a converged spot on third optical recording medium by a combination of a refraction action of the aspheric surface and an optical action given by at least one of the first phase structure and the second phase structure.
摘要:
An optical pickup apparatus for information recording and/or reproduction on different optical information recording media with compatibility among these media, the optical surface of a first objective lens and the optical surface of a second objective lens are formed only of a refractive surface. The second objective lens is used in common for the first light flux with a wavelength of λ1 and the second light flux with a wavelength of λ2, but in the case where the protective substrate t2 of the second optical information recording medium and the protective substrate t3 of the third optical information recording medium are the same, it is not necessary to take the difference in thickness of the protective substrate into consideration. Chromatic aberration based on the difference in wavelength between the first light flux and the second light flux can be corrected by displacing the second coupling lens.
摘要:
An optical system has an optical functional surface including a common region used for conducting information recording and/or reproducing for both of a first optical information recording medium and a second optical information recording medium. The common region comprises a refractive surface of an imaginary basic aspherical surface and a optical path difference providing structure in which plural ring-shapes zones are separated around the center of an optical axis and neighboring ring-shaped zones are displaced to each other in a direction of an optical axis so as to cause an optical path difference obtained by multiplying a predetermined wavelength λs (λ1
摘要:
An objective optical element of an optical pickup apparatus has a magnification m1 satisfying the following formula for a light flux of the wavelength λ1:−1/7≦m1≦−1/25 and |m1 |
摘要:
An optical pickup apparatus comprising: a first light source emitting first light flux having wavelength λ1 (380 nm≦λ1≦450 nm); a second light source emitting second light flux having wavelength λ2 (600 nm≦λ2≦700 nm); a third light source emitting third light flux having wavelength λ3 (750 nm≦λ3≦800 nm); a first divergent angle-converting element through which the first light flux passes; a second divergent angle-converting element through which the second light flux and the third light flux pass; and an objective optical element through which the first, second, and third light fluxes pass. Optical magnification m2 of the second divergent angle-converting element for the second light flux and optical magnification m3 of the second divergent angle-converting element for the third light flux are different from each other.
摘要:
An optical pickup apparatus comprising: a first, second and third light sources emitting first, second and third light flux having first wavelength of λ1, second wavelength of λ2 and third wavelength of λ3, respectively; and an objective optical system converging the first, second and third light fluxes onto an information recording surface of a first, second and third optical disk, respectively, wherein the objective optical system has a phase structure, and wherein when a first, second and third magnifications of the objective optical system for conducting reproducing information from and/or recording information on the first, second and third optical disks are represented by M1, M2, and M3, respectively, |dM1−M2|, which represents an absolute value of a difference between M1 and M2, satisfies the following relation. |dM1−M2|