摘要:
A swing-arm type optical recording and reproducing apparatus and an optical disk applicable to the same. The optical disk includes a substrate having an information recording surface to record and reproduce an information signal, and a protective layer which is provided on the information recording surface and whose surface facing a slider is a flat even surface so that variations in a floating height of the slider can be reduced. The optical recording and reproducing apparatus further includes, an optical head having a light source provided at a swing arm to emit light of a predetermined wavelength; an optical path changing means provided in the optical path of the light emitted from the light source for changing the proceeding path of incident light; a collimating lens installed at the slider to preliminarily converge the light emitted from the light source and entering via the optical path changing means; an objective lens installed at the slider to converge the light which is emitted from the light source and enters via the optical path changing means to form an optical spot on the optical disk; and a photodetector to receive the light which is reflected from the optical disk and enters via the objective lens, the collimating lens, and the optical path changing means. The optical head detects an information signal and an error signal in order to reduce defocus due to variations in ambient temperature and variations in the wavelength of the light of the light source.
摘要:
An optical pickup apparatus having an objective lens which is formed of a single lens such that the maximum slope angle of a surface of the lens is less than 55° with respect to a high NA of 0.7 or more. The objective lens can be manufactured to satisfy a condition of allowance in optical aberration and have a high NA of 0.7 or more unlike a typical objective lens formed of a single lens. Also, the optical pickup apparatus adopting the objective lens can be used for high density recording and reproduction and provide a reduced volume, a simple structure, and/or a low price. Also, since the optical pickup apparatus adopting the objective lens has a very short working distance, the first reflection surface recording method can be adopted. Accordingly, the thickness of the optical pickup apparatus can be manufactured as thin as a protective layer of a typical recording medium.
摘要:
A projection type image display apparatus includes a light source emitting light, a polarization device transmitting light polarized in one direction of incident light emitted from the light source, a reflection type image generating unit generating a color image from incident light and reflecting the generated color image to proceed along a path different from a path of the incident light, a light deflection device deflecting the image reflected by the image generating unit, and a projection lens unit magnifying and transmitting the image generated by the image generating unit and deflected by the light deflection device to proceed toward a screen. Thus, a full color can be realized with respect to the area of a pixel, and an efficiency in use of light and resolving power can be improved.
摘要:
A solid immersion mirror (SIM) type objective lens and an optical pickup employing the same. The objective lens has a first curved surface which condenses incident light and a second curved surface surrounding the first curved surface which diverges incident light. A second transmission surface disposed to face the first transmission surface has an area which transmits incident light and a first reflection surface surrounding the second transmission surface which reflects incident light. A second reflection surface which surrounds the second curved reflects incident light. The objective lens realizes an NA of 0.7 or more with a single lens; has a working distance enabling far field recording/reproducing; has a smaller blocking area than that of the conventional SIM; and generates a smaller amount of side lobe. Where the objective lens is adopted in an optical pickup device, generation of jitter during reproduction or cross erasure during recording is minimized.
摘要:
A reflection type compound prism and an optical pickup apparatus employing the same. As a light beam is passed through the compound prism, a size of the light beam in a direction perpendicular to a reference plane is reduced by a first reflection surface, propagated toward an objective lens by second and third reflection surfaces and the size restored by reflecting the light beam from a fourth reflection surface forming an angle less than 45° with respect to the reference plane so that a height of an optical system is reducible to obtain a small thin optical pickup with a desired NA. The second and third reflection surfaces are spaced apart in a direction perpendicular to the reference plane by an amount close to a diameter of the light beam at a point of incidence of the light beam with the compound prism.
摘要:
A front projection type screen includes a transparent base; a diffusion member formed on one surface of the transparent base; and a retroreflection prism array formed on another surface of the transparent base. Thus, a wide angle of visibility can be secured in a horizontal direction while an angle of visibility in a vertical direction is limited to a narrow scope. Also, a wide viewing angle can be achieved and high efficiency and brightness of light may be obtained.
摘要:
An optical pickup includes a light source emitting a laser beam and an optical path changing unit altering a traveling path of an incident beam. An objective lens, disposed on an optical path between the optical path changing unit and an optical disk, focuses the incident beam from the light source to form a light spot on the optical disk of the objective lens. The optical pickup further includes a photodetector and an detecting-correcting unit, arranged on the optical path between the optical path changing unit and the objective lens, performing at least one of detecting the thickness of the optical disk and correcting aberration caused by thickness variations of the optical disk. The objective lens includes a first transmitting portion divergently transmitting an incident beam, where the first transmitting portion is at a relatively near-axis region from an optical axis of the objective lens. A second transmitting portion transmits the incident beam, where the second transmitting portion is arranged facing the first transmitting portion. A first reflecting portion condenses and reflects the incident beam from the first transmitting portion, where the first reflecting portion is formed around the second transmitting portion. A second reflecting portion condenses and reflects the incident beam from the first reflecting portion towards the second transmitting portion, where the second reflecting portion is formed around the first transmitting portion.
摘要:
A disc balancing device and a method thereof. The disc balancing device includes a disc assembly having a driving source, and a disc rotatably disposed at the driving source, a displacement measurement unit measuring vibration in the rotation of the disc assembly, a phase angle measurement unit measuring a phase angle from a reference point of the disc assembly in the rotation of the disc assembly, an operation/control unit calculating an eccentric mass and an eccentric position of the disc assembly, by using the biased vibration measured in the displacement measurement unit and the phase angle measured in the phase angle measurement unit, and a laser cutter tracking and laser-cutting the side portion of the disc corresponding to the eccentric position according to the information from the operation/control unit, whereby the eccentric mass of the disc assembly is balanced to reduce vibration in the rotation.
摘要:
An optical pickup includes a light source emitting a laser beam and an optical path changing unit altering a traveling path of an incident beam. An objective lens, disposed on an optical path between the optical path changing unit and an optical disk, focuses the incident beam from the light source to form a light spot on the optical disk of the objective lens. The optical pickup further includes a photodetector and an detecting-correcting unit, arranged on the optical path between the optical path changing unit and the objective lens, performing at least one of detecting the thickness of the optical disk and correcting aberration caused by thickness variations of the optical disk. The objective lens includes a first transmitting portion divergently transmitting an incident beam, where the first transmitting portion is at a relatively near-axis region from an optical axis of the objective lens. A second transmitting portion transmits the incident beam, where the second transmitting portion is arranged facing the first transmitting portion. A first reflecting portion condenses and reflects the incident beam from the first transmitting portion, where the first reflecting portion is formed around the second transmitting portion. A second reflecting portion condenses and reflects the incident beam from the first reflecting portion towards the second transmitting portion, where the second reflecting portion is formed around the first transmitting portion.
摘要:
A compatible optical pickup device includes a single light source to emit a light having a wavelength longer than 650 nm, an objective lens having a near axis area, a ring type annular lens area, and a far axis area to focus the light to form light spots suitable for a first relatively thin optical disk and a second relatively thick optical disk to form a first light spot having an FWHM (full width at half maximum) of 0.72 μm or less for the first optical disk and a second light spot having an FWHM of 0.8 μm or more for the second optical disk, an optical path changer to change a proceeding path of incident light, and a photodetector to receive light reflected by the optical disk and having passed through the objective lens and the optical path changer and to detect an information signal and/or an error signal.