Abstract: An image display device includes a light source which outputs a first light including a first color light, a second color light and a third color light, a polarity converter which unifies polarities of the first light into a single polarity, a dichroic mirror which separates the first color light from the first light which is output by the polarity converter, and first to third reflective liquid crystal display elements, respectively, installed for the first to third color lights. First to third polarized beam splitters are provided together with first and second wavelength selective polarity rotator elements. A projection lens is provided so as to project a light combined by the third polarized beam splitter, and the first color light, which is reflected by the first reflective liquid crystal display element, permeates the first polarized beam splitter and the third polarized beam splitter.

Abstract: A liquid crystal display apparatus, comprises: a liquid crystal display (3); and a plural numbers of light emitting diodes (7), as a directly underlying type backlight, which is disposed on a rear surface of the liquid crystal display, so as to irradiate lights upon said liquid crystal display, wherein a translucent light guidance member (5), which is provided at least corresponding to each one or more of the plural numbers of light emitting diodes, and the translucent light guidance member (5) is in a cylindrical configuration, and reflection surfaces are defined on each of outer wall surfaces (53) and inner wall surfaces (52) of the cylindrical light guidance member, so as to reflect the lights from the light emitting diodes upon those reflection surfaces, and thereby guiding them onto a side of the liquid crystal display by those reflection surfaces.

Abstract: A high-luminance projection type image display apparatus is realized by improving a conventional polarization converter unit. Light-beam split means 21 for splitting light from a light source is arranged before a polarization converter unit 960 having a plurality of incidence surfaces, and the light coming from the polarization converter unit 960 enters a rod integrator 24.

Abstract: A projection type image display apparatus able to improve the utilization efficiency of light and attain a high luminance of light. An optical waveguide for guiding light emitted from a light source is provided, and a color separator for transmitting predetermined color light included in the light guided by the optical waveguide and for reflecting predetermined color light included in the guided light is also provided. The light reflected by the color separator is guided by the optical waveguide and is thereafter reflected by a reflecting member. The light reflected by the reflecting member is radiated into the optical waveguide and conducted thereby to the color separator.

Abstract: In a projection type image display apparatus, it is intended to reliably facilitate assembly of optical members for polarization treatment and phase difference compensation of light. The optical members are each configured such that a protective layer such as a magnesium fluoride layer or an aluminum oxide layer is formed by vapor deposition over a light permeable substrate of cubic system structure comprising, for example, magnesium oxide and an adhesive layer is provided on the protective layer for fixing the element layers of a polarization element, a view angle compensation element, etc.

Abstract: An image display device includes a light source which outputs a first light including a first color light, a second color light and a third color light, a polarity converter which unifies polarities of the first light into a single polarity, a dichroic mirror which separates the first color light from the first light which is output by the polarity converter, and first to third reflective liquid crystal display elements, respectively, installed for the first to third color lights. First to third polarized beam splitters are provided together with first and second wavelength selective polarity rotator elements. A projection lens is provided so as to project a light combined by the third polarized beam splitter, and the first color light, which is reflected by the first reflective liquid crystal display element, permeates the first polarized beam splitter and the third polarized beam splitter.

Abstract: An image display device has three reflective image display elements for red, green and blue to form an optical image according to a video signal from light output from a light source, and an optical system to supply light onto the display elements and to combine and output the light reflected from the display elements. The image display device includes a first polarity converting unit to convert luminous flux from the light source to S polarized light, a first polarized beam splitter, and second polarized beam splitter. The reflective image display element for green is provided in a vicinity of the first polarized beam splitter, and the light reflected by the first polarized beam splitter and input to the reflective image display element for green is S polarized light. The light output from the reflective image display element for green permeates the first and second polarized beam splitters.

Abstract: An image display device has three reflective image display elements for red, green and blue to form an optical image according to a video signal from light output from a light source, and an optical system to supply light onto the display elements and to combine and output the light reflected from the display elements. The image display device includes a first polarity converting unit to convert luminous flux from the light source to S polarized light, a first polarized beam splitter, and second polarized beam splitter. The reflective image display element for green is provided in a vicinity of the first polarized beam splitter, and the light reflected by the first polarized beam splitter and input to the reflective image display element for green is S polarized light. The light output from the reflective image display element for green permeates the first and second polarized beam splitters.

Abstract: An image display device has three reflective image display elements for red, green and blue to form an optical image according to a video signal from light output from a light source, and an optical system to supply light onto the display elements and to combine and output the light reflected from the display elements. The image display device includes a first polarity converting unit to convert luminous flux from the light source to S polarized light, a first polarized beam splitter, and second polarized beam splitter. The reflective image display element for green is provided in a vicinity of the first polarized beam splitter, and the light reflected by the first polarized beam splitter and input to the reflective image display element for green is S polarized light. The light output from the reflective image display element for green permeates the first and second polarized beam splitters.

Abstract: A projective display apparatus having an illumination unit which includes a light source, an integrator lens and a collimator lens, a light splitter unit which splits light beams from the illumination unit into a plurality of color components, a plurality of light valves, a cooling fan, and a wind guiding unit. A respective one of the light valves corresponds to a respective one of the color components. The wind guiding unit guides the cooling wind from the cooling fan to the illumination unit and the light valves. The wind guiding unit splits and forms at least two branch wind guiding paths. One of the branch wind guiding paths guides cooling wind from the cooling fan to the illumination unit and another of the branch wind guiding paths guides the cooling wind to the light valves.

Abstract: An image display device has three reflective image display elements for red, green and blue to form an optical image according to a video signal from light output from a light source, and an optical system to supply light onto the display elements and to combine and output the light reflected from the display elements. The image display device includes a first polarity converting unit to convert luminous flux from the light source to S polarized light, a first polarized beam splitter, and second polarized beam splitter. The reflective image display element for green is provided in a vicinity of the first polarized beam splitter, and the light reflected by the first polarized beam splitter and input to the reflective image display element for green is S polarized light. The light output from the reflective image display element for green permeates the first and second polarized beam splitters.

Abstract: A projective display apparatus having an illumination unit which includes a light source, an integrator lens and a collimator lens, a light splitter unit which splits light beams from the illumination unit into a plurality of color components, a plurality of light valves, a cooling fan, and a wind guiding unit. A respective one of the light valves corresponds to a respective one of the color components. The wind guiding unit guides the cooling wind from the cooling fan to the illumination unit and the light valves. The wind guiding unit splits and forms at least two branch wind guiding paths. One of the branch wind guiding paths guides cooling wind from the cooling fan to the illumination unit and another of the branch wind guiding paths guides the cooling wind to the light valves.

Abstract: A compact, lightweight, low cost image display device with high image quality and improved brightness are attained by a combination of a color separating means and color separating/combining means and color combinations means and two reflecting means and polarizing plate to change the polarization direction of the light and a polarized beam splitter on the optical axis of reflective liquid crystal display element.

Abstract: A display optical unit includes a light valve which modulates light to form picture information, a light splitter which splits light into a plurality of color components and for directing each of the color components to the light valve, an illumination unit which directs light emanated from a light source to the light splitter, and a projection lens which magnifies and projects the modulated light having the picture information for displaying a picture. An optical axis of the projection lens is shifted from an optical axis of the illumination unit and the light splitter, and a projection lens unit including the light valve and the projection lens has a positioning mechanism which determines a position thereof when attached and is attachable and detachable in a direction perpendicular to an optical axis of the projection lens unit.

Abstract: A compact, lightweight, low cost image display device with high image quality and improved brightness are attained by a combination of a color separating means and color separating/combining means and color combinations means and two reflecting means and polarizing plate to change the polarization direction of the light and a polarized beam splitter on the optical axis of reflective liquid crystal display element.

Abstract: A display optical unit includes a light valve which modulates light to form picture information, a light splitter which splits light into a plurality of color components and for directing each of the color components to the light valve, an illumination unit which directs light emanated from a light source to the light splitter, and a projection lens which magnifies and projects the modulated light having the picture information for displaying a picture. An optical axis of the projection lens is shifted from an optical axis of the illumination unit and the light splitter, and a projection lens unit including the light valve and the projection lens has a positioning mechanism which determines a position thereof when attached and is attachable and detachable in a direction perpendicular to an optical axis of the projection lens unit.

Abstract: A display optical unit and apparatus in which the optical axis of a projection lens is shifted from the optical axis of an illumination unit and light splitter. The projection lens is attachable and detachable in a direction in which the optical axes are shifted from each other. A light valve or a polarizer is cooled by cooling winds blown by a cooling device to the light valve or polarizer through a plurality of wind supply openings are arranged in directions different from one another and within the range of 45 degrees to 315 degrees so as to enable cooling of the display optical unit.

Abstract: A drum base according to he invention, on which a drum of a magnetic tape recorder is mounted, comprises a substantially annular frame having a fixing surface to which the drum is fixed; at least one through hole extending through the fixing surface for allowing a screw which is to be threadably attached to a threaded hole formed in the drum to pass therethrough; and a pair of mounting surfaces provided on the fixing surface on which the drum is mounted, the mounting surfaces being located adjacent to the at least one through hole so as to have a symmetrical relationship in a circumferential direction of the annular frame with respect to the at least one through hole and within a range of a diameter dimension of the at least one through hole in a radial direction of the annular frame.

Abstract: Disclosed in an arrangement to achieve satisfactory head contact by increasing contact face pressure at a head gap and to reduce the change in time of head contact performance in a double azimuth head. Heads in a portion in which a tape is slid are respectively constructed with each head having two different arcs with a radius of curvature R1 in a first area which includes a gap, and with a radius of curvature R2 in a second area which is adjacent to the first area. A transition portion P for transitioning an arc with the radius of curvature R1 and an arc with the radius of curvature R2 is located in the direction of its adjacent head based upon a contact point Q on R1 of a common tangent drawn from an arc forming a periphery of a rotating drum to a circle formed by R1. The relationship between the radiuses of curvature in two areas is set to R1>R2.

Abstract: As a method of increasing the storage capacity of a magnetic recording and reproducing apparatus for recording and reproducing information to and from a magnetic tape in a cartridge, there is a helical scan recording method in which the magnetic tape is diagonally wound around a drum which rotates a magnetic head. With an apparatus adapted to this method, the disposition of the cartridge and the take-up reel for taking up the magnetic tape on the same plane arises a necessity of considerably bending the magnetic tape at the drum portion and, accordingly, the magnetic tape is damaged. In order to prevent the damage of the foregoing type, the tape passage surface from the cartridge to the drum and the tape passage from the drum to the take-up reel are formed by an angle at which the direction in which the magnetic tape is moved is changed due to winding of the magnetic tape around the drum so that the magnetic tape is not bent excessively.