Abstract: An optical scanning device includes a rotationally-moving mirror on which a reflection plane is provided in a rotationally-movable manner, and a sealing unit over which a light-transmissive cover is provided, a first plane of the light-transmissive cover, a second plane of the light-transmissive cover, and the reflection plane of the rotationally-moving mirror within a rotationally-moving range being non-parallel to each other, the first plane being on the opposite side to the side of the rotationally-moving mirror, the second plane being on the side of the rotationally-moving mirror.

Abstract: A light source device and an image display apparatus include a Blue Laser Diode (B-LD) light source unit, a dichroic mirror to reflect substantially collimated Blue (B) light from the B-LD light source unit, a lens to focus the B light reflected by the dichroic mirror, and a color wheel comprising a Green (G) fluorescent section which is excited by the collimated B light to emit and to reflect G light and a B mirror reflector to mirror-reflect the B light, wherein a center of a light flux of the B light reflected by the dichroic mirror is on other than an optical axis of the lens.

Abstract: An optical pickup of this invention includes a first objective lens for a CD or DVD, a second objective lens for a BD, a photodetector, a light source for a CD or DVD, a light source for a BD; a first optical mechanism for guiding first reflected light from the CD or DVD toward the photodetector via the first objective lens, and a second optical mechanism for guiding second reflected light from the BD via the second objective lens and changing the direction of the second reflected light toward the first optical mechanism. After the second reflected light joins a light path of the first reflected light guided by the first optical mechanism, the second reflected light is supplied by the first optical mechanism to the photodetector.

Abstract: An optical pickup for writing information to and/or for reading information from an optical disc having at least two recording layers (dual layer) provided with first and second recording layers can prevent layer crosstalk resulting from disturbing a signal reproduced from the first recording layer by a reflected light beam reflected from the second recording layer during a writing operation for writing information to the first recording layer or a reading operation for reading information from the fist recording layer. An orthogonal polarization region forming component forms an orthogonal polarization region, in which respective directions of polarization of a first light beam focused on and reflected by a first recording layer of an optical disc and a second light beam reflected by a second recording layer of the optical disc are perpendicular to each other, in a region, in which the first and the second light beam overlap each other, on a light-receiving surface of a detector.

Abstract: An optical pickup has a first compatible objective and a second compatible objective, the first objective having a diffractive lens structure capable of recording and playback to and from CD and HD DVD, the second objective having a diffractive lens structure capable of recording and playback to and from both DVD and BD. The first objective has the diffractive lens structure that meets the condition of 0.75?(?1×m1)/(?3×m3)?0.99, where m1 and m3 are diffraction orders of diffracted lights used to read and write CD and HD DVD. The second objective has the diffractive lens structure that meets the condition of 0.75?(?4×m4)/(?2×m2)?0.99, where m2 and m4 are diffraction orders of diffracted lights used to read and write DVD and BD.

Abstract: An optical pickup for writing information to and/or for reading information from an optical disc having at least two recording layers (dual layer) provided with first and second recording layers can prevent layer crosstalk resulting from disturbing a signal reproduced from the first recording layer by a reflected light beam reflected from the second recording layer during a writing operation for writing information to the first recording layer or a reading operation for reading information from the fist recording layer. An orthogonal polarization region forming component forms an orthogonal polarization region, in which respective directions of polarization of a first light beam focused on and reflected by a first recording layer of an optical disc and a second light beam reflected by a second recording layer of the optical disc are perpendicular to each other, in a region, in which the first and the second light beam overlap each other, on a light-receiving surface of a detector.

Abstract: An optical disc apparatus compatible with both BD and HD-DVD specifications and also compatible with DVD and CD. An optical head has a first light source for emitting light having a first wavelength, a second light source for emitting light having a second wavelength, a third light source for emitting light having a third wavelength, a first objective lens for irradiating light emitted from the first or second light source to an optical disc, and a second objective lens for irradiating light emitted from the first or third light source to an optical disc. A light source and objective lens to be used are changed in accordance with BD, HD-DVD, DVD and CD.

Abstract: A liquid crystal projector, having a configuration in which an exhaust fan is arranged adjacently to a projection lens at an angle to the optical axis of the projection lens, a configuration including a plurality of tilted wind-directing plates, a configuration in which the arrangement of a first reflection mirror, a first lens array, a light source and the exhaust fan is substantially parallel and adjacent to the arrangement of the projection lens, a dichroic prism and a second dichroic mirror, and/or a configuration in which the lens array has the incident surface thereof made of a concave lens.

Abstract: A liquid crystal projector, having a configuration in which an exhaust fan is arranged adjacently to a projection lens at an angle to the optical axis of the projection lens, a configuration including a plurality of tilted wind-directing plates, a configuration in which the arrangement of a first reflection mirror, a first lens array, a light source and the exhaust fan is substantially parallel and adjacent to the arrangement of the projection lens, a dichroic prism and a second dichroic mirror, and/or a configuration in which the lens array has the incident surface thereof made of a concave lens.

Abstract: In a liquid crystal projector using a reflective and scattering or reflective type liquid crystal panel, a plurality of light sources are used, thereby securing sufficient brightness of an image, increasing the F-number of a projection lens, and miniaturizing and lightening the projector. A light source is arranged right next to the projection lens and an exhaust port is arranged on the front face of the projector, thereby preventing hot heat discharged from the exhaust port from being discharged toward peripheral equipment or the operator.

Abstract: In a polarization transforming optics having a polarizing beam splitter (PBS) for transforming x-direction incident light flux from a metal halide light source into a single linearly (z direction) polarized light flux beam heading in the y direction and delivering the beam to, preferably, a light valve of a liquid crystal display (LCD) in a coordinate space, the PBS splits the incident light flux from the light source into split light flux beams, separates the split light flux beams into linearly polarized light flux beams having polarizing directions which are orthogonal to each other, and delivers two linearly polarized outgoing light flux beams having polarizing directions which are orthogonal to each other and heading in directions parallel to a polarizing direction plane. One of the two outgoing light flux beams is deflected by a single mirror to have the same heading direction and polarizing direction as those of the other.

Abstract: A projection lens system for a projection type television having a cathode-ray tube with a panel having a fluorescent inner surface for projecting an image onto a screen. The projection lens system includes a plurality of lens groups, the lens group positioned at a side nearest to the cathode-ray tube including, in successive order from a side toward the screen, a lens having a concave surface on the screenn side a transparent medium, and the cathode-ray tube panel having a fluorescent inner surface, the lens group attenuating at least a part of a wavelength region of the light emitted on the fluorescent surface so as to improve contrast while reducing observance of a ghost image due to multiple reflection without substantial impairment in at least one of brightness and luminance. More particularly, the attenuation is provided by the concave lens having at least one surface dyed in a predetermined color.

Abstract: A projection-type stereoscopic image display system is disclosed in which a left-eye projection light ray and a right-eye projection light ray are projected from behind a transparent screen thereby to display a stereoscopic image.

Abstract: A rear projection screen for use in a rear projection image display device comprises one or more sheet members through which light is sequentially transmitted from the side of a plane of incidence of the screen, the last sheet member comprising a transparent material as a base thereof, and a light diffusing layer provided on the side of a plane of emergence of the base. A light diffuser having a refractive index different from that of the base may be dispersed in the base so as to contrive a greater viewing angle. Further, a transperent binder for supporting the light diffuser dispersed in the light diffusing layer or the light diffuser itself may be colored in order to obtain a further enhanced contrast.