摘要:
A projection-type image display apparatus having a structure adapted so that the efficiency of the use of light and resolving power thereof can be enhanced. The projection-type image display apparatus includes a light source; a color separation unit separating incident rays according to predetermined wavelengths, and directing the separated rays at different angles; a lens array dividing the rays separated by the color separation unit into predetermined pixels; a driving portion driving the lens array to change the proceeding paths of the color rays; a polarizing beam splitter changing a proceeding path of incident rays depending on a direction of polarization; a reflection-type display device producing a color image using the rays entering via the polarizing beam splitter, and reflecting the color image toward the polarizing beam splitter; and a projection lens unit magnifying and projecting an incident image onto a screen. In addition, the projection-type image display apparatus may comprise. Alternative designs include a transmission-type display device in place of the reflection-type display device and a deflector changing the proceeding paths of the individual color rays separated by the color separation unit instead of the driving portion.
摘要:
An optical pickup device includes a light unit for irradiating a light beam having a wavelength longer than 650 nm onto a recording medium and receiving and detecting a light beam reflected by the recording medium, and an objective tens formed of a single lens having an NA of 0.7 or more to form a light spot on the recording medium by condensing an incident light beam emitted from the light unit. A recording medium has a recording density of a DVD family or more and is formed of a material suitable for a long wavelength of 700 nm or more so that a reproduction signal by a reflectance of a recording surface is optimized. Thus, a compact high density optical recording/reproducing apparatus which is inexpensive and has high performance can be realized.
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 recording/reproducing apparatus including an optical pickup compatible with a plurality of optical recording media each using light of a different wavelength. The optical pickup includes at least one light source, an objective lens having a function of focusing light emitted from the light source into the optimal light spot on an information recording surface of one of the plurality of the optical recording media, and a light detector to detect light transmitted through the objective lens after being reflected from the information recording surface of the optical recording medium on which the light spot is formed. The objective lens has an inner area, an annular lens area and an outer area such that the annular lens area divides the inner area from the outer area and has a ring shape centered at a vertex. The inner area, the annular lens area and the outer area have aspherical surface shapes to focus light transmitted through the inner area and the outer area into a single light spot by which information can be read from the information recording surface of a relatively thin first optical recording medium and scatter light transmitted through the annular lens area located between the inner area and the outer area so that information cannot be read from the information recording surface of the first optical recording medium, during reproduction of the first optical recording medium. The inner area and the annular lens area transmit light into a single light spot by which information can be read from the information recording surface of a relatively thick second optical recording medium and scatters light transmitted through the outer lens area so that information cannot be read from the information recording surface of the second optical recording medium, during reproduction of the second optical recording medium.
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 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 device includes a light module, emitting light and receiving light reflected from a recording medium, and a solid immersion lens (SIL) member disposed in an optical path between the light module and the recording medium. The SIL has a planar surface facing the recording medium and a plurality of elliptically curved surfaces opposite the recording medium. The elliptically curved surfaces have different radii of curvature arranged symmetrical with respect to a central axis for focusing the incident light to form a tight beam spot on a recording plane of the recording medium.
摘要:
A reproducing/recording optical pickup compatible with discs having different thicknesses includes a transparent plate having a central portion formed with a diffraction grating pattern for diffracting the light travelling from the light source to the objective lens, and a transparent portion through which the light passes, and a photodetector having first and second light receiving portions. The zero-order transmitted light and the passing light are focused using all regions of the aperture of the objective lens with respect to a thin disc. The positive first-order diffracted light diffracted by the diffraction grating pattern of the transparent plate is focused onto a thick disc by partial regions of the objective lens. Then, the reflected lights thereof are detected by the first and second light receiving portions, respectively. Because signals for reproduction and servo for each disc are detected as the detection signals of the first and second light receiving portions, stable servo and noiseless reproduction are possible, irrespective of the thickness of the disc used.
摘要:
An optical pickup compatible with a plurality of optical recording media each using light of a different wavelength. The optical pickup includes at least one light source, an objective lens having a function of focusing light emitted from the light source into the optimal light spot on an information recording surface of one of the plurality of the optical recording media, and a light detector to detect light transmitted through the objective lens after being reflected from the information recording surface of the optical recording medium on which the light spot is formed. The objective lens has an inner area, an annular lens area and an outer area such that the annular lens area divides the inner area from the outer area and has a ring shape centered at a vertex. The inner area, the annular lens area and the outer area have aspherical surface shapes to focus light transmitted through the inner area and the outer area into a single light spot by which information can be read from the information recording surface of a relatively thin first optical recording medium and scatter light transmitted through the annular lens area located between the inner area and the outer area so that information cannot be read from the information recording surface of the first optical recording medium, during reproduction of the first optical recording medium. The inner area and the annular lens area transmit light into a single light spot by which information can be read from the information recording surface of a relatively thick second optical recording medium and scatters light transmitted through the outer lens area so that information cannot be read from the information recording surface of the second optical recording medium, during reproduction of the second optical recording medium.
摘要:
A lens device which can be used as an objective lens in an optical pickup apparatus includes an objective lens provided along a light path facing a disc and having a predetermined effective diameter, and light controlling means provided along the light path for controlling the light in an intermediate region between near and far axes of an incident light beam, thus providing a simplified and inexpensive device for using discs of differing thickness in a single disc drive, by reducing the spherical aberration effect.