Abstract: A color separating/light guiding optics comprises two independent dichroic mirrors, reflection mirrors and correcting lenses. A horizontal plane region occupied by these optical components is entirely involved in a horizontal plane region occupied by a light modulating/color compositing/image projecting optics. A red beam is guided along a detoured optical path extending across a dead space below a projection lens. Although the optical path length of the red beam becomes longer than those of the blue beam and the green beam, the detoured optical path provides a sufficient space for installing the correcting lenses. The substantial optical path lengths of three primary color beams can be equalized with each other by the provision of these correcting lenses.

Abstract: A laser video projector for projecting an image to a plurality of screens is provided. It is possible to display an identical image to a plurality of screens by modulating light from the light source by an acousto-optic modulator (AOM) according to a video signal and projecting video information to a plurality of screens using a scanner.

Abstract: An overhead projector of the under mirror type includes a projection head assembly supported on a column so as to be located over a stage on the top of a housing and so as to be pivotable between a standing position and a stowed position. A projection lens is fixed on a lens frame and a reflecting mirror is fixed on a mirror plate. Both the lens frame and the mirror plate are rotatably mounted on a single shaft further mounted on the head body of the projection head assembly so that angles of the lens and the mirror are increased and decreased. The lens frame is rotated by a self-weight of the lens in such a direction that the angle of the lens is decreased, when the projection head assembly assumes the standing position. A link lever interconnects the lens frame and the mirror plate so that the angles of them are adjusted so that the angle of the lens doubles that of the mirror. A mirror locking element locks the mirror at a position where the angle of the mirror is maximum.

Abstract: An image display apparatus includes a storage display element having a screen portion which receives image light from its back side and stores and displays an image, and a light blocking mechanism. The light blocking mechanism is capable of being switched over between a light-blocked state in which the light blocking mechanism blocks light incident on the front side of the screen portion of the storage display element to shut off incidence of external light on the screen portion, and an observation-possible state in which the light blocking mechanism unblocks light incident on the front side of the screen portion of the storage display element.

Abstract: A multimedia projector (110) employing a color wheel (120) uses a light guide (152) to transmit light from the color wheel to a photo detector (156) that detects a particular color or colors of light to provide a index mark signal to a display controller (56) to synchronize red, green, and blue image data with the associated color wheel filter segments. An integrator tunnel (122) adjacent to the light guide provides uniform, high intensity light from the color wheel to a display device, such as a DMD (130). The photo detector senses otherwise wasted light rays as sensing rays (150) that are reflected by a light source reflector (114) and propagated through the color wheel. To collect some of the sensing rays, the light guide is preferably bonded to the integrator tunnel. The light guide has a slanted output end (154) that reflects the collected sensing rays toward a photo detector on a circuit board (148).

Abstract: A dark field projection display includes a light source, a spatial light modulator, and an optical system for directing light from the light source onto the spatial light modulator. The optical system includes a plurality of optical subsystems and a plurality of reflectors. Each of the optical subsystems has an input aperture and is arranged to image light from the light source, the subsystems forming a spatial distribution of source images whose relative positions are different from the relative positions of the input apertures. Each of the optical subsystems further includes a plurality of reflectors disposed at the relative positions of the source images. Each of the reflectors is arranged to reflect light from a respective one of the subsystems onto the spatial light modulator.

Abstract: To provide a projection display device which can easily produce a high contrast, bright projection image, without obliquely mounting the light source. In a projection display device, a condenser lens is disposed such that its optical axis is disposed at a location parallel to an optical axis of a light source by moving the optical axis of the condenser lens with respect to the optical axis L of the light source in substantially the same direction that an optical axis of a projection lens 60 is moved with respect to the optical axis of the light source. Therefore, light can obliquely illuminate a liquid crystal light valve, and can be efficiently guided to the projection lens. Consequently, a high contrast, bright projection image can be easily provided.

Abstract: A .lambda./4 phase plate 821 is placed in an optical path between a blue light liquid crystal valve 811 and a cross-dichroic prism 813. S-polarized blue light incident on the blue Light liquid crystal light valve 811 is transmitted by an s-polarized light transmitting polarizer 811a without change, modulated by a liquid crystal panel 811b and a part thereof is converted into p-polarized light, and the p-polarized light is transmitted by a p-polarized light transmitting polarizer 811c to be emitted. The emitted p-polarized light is incident on the .lambda./4 phase plate and converted into circularly polarized light to be emitted, and is incident on the cross-dichroic prism 813. The circularly polarized light reflected from a red reflecting film 831 and a blue reflecting film 833 and incident on the .lambda.

Abstract: A projection-type display apparatus in accordance with the invention reduces the margin formed around the image forming range of the light valves, and forms a bright projected image. Emitted light from a light source lamp unit of a projection-type display apparatus illuminates liquid crystal light valves of each color via an integrator optical system. First and second lens plates of an integrator optical system that serves as a uniform illuminating optical system are disposed such that the attachment position thereof is capable of fine adjustment in a direction vertical to the optical axis. By performing fine adjustment of the attachment position of these, the forming position of the illumination range B can be adjusted to include the image forming range A of the liquid crystal light valves. Accordingly, there is no need to provide a wide margin around the image forming range A, taking shifting of the forming position of the illumination range B into consideration.

Abstract: The polarized light illuminator of this invention includes: a light source; a first fly's eye lens and a second fly's eye lens disposed in this order from the light source; a polarization separation element disposed between the light source and the second fly's eye lens for separating unpolarized light into a first polarized light component and a second polarized light component having polarization directions perpendicular to each other, to output the first polarized light component and the second polarized light component in different directions from each other; and a polarization conversion element disposed near the second fly's eye lens for converting the first polarized light component and the second polarized light component output from the polarization separation element into unidirectionally polarized light, wherein the polarization separation element has a first flat plate and a second flat plate, the first flat plate having a polarization separation surface for reflecting the first polarized light co

Abstract: An image to be projected is deformed to obtain a projected image having small distortion. An image deforming device constituted by an optical fiber bundle is arranged in front of an original of a projector arranged at a position other than the center of a dome, so that the image of the original is transmitted from an end face on the incident side of an image correction device to an end face on the emission side as images divided into pixels using optical fibers as units. A secondary image subjected to predetermined deformation is displayed on the end face on the emission side, and the secondary image is projected on a dome surface to obtain a projected image which is free from distortion by the same manner as that performed when the original is projected from the center of the dome onto the same projection surface.

Abstract: An illuminating apparatus includes an inner surface reflection type integrator, a condensing optical system for condensing light from a light source on or near the light incidence portion of the integrator, and an imaging optical system for imaging the light emergence portion of the integrator or the vicinity thereof on a surface to be illuminating. The integrator reflects at least part of light which has entered the interior thereof from the light incidence portion thereof by the inner surface thereof to thereby propagate it to the light emergence portion thereof, thereby forming light of which the intensity distribution has been uniformized on or near the light emergence portion. The imaging optical system has a polarizing beam splitter for dividing the light from the integrator into a plurality of polarized lights differing in the direction of polarization from one another.

Abstract: A projection display device that promotes size reduction thereof, and that allows an optical system including optical modulation devices to be equitably and efficiently cooled. The projection display device includes a head body having an optical modulation device, a color synthesizing optical system, and a projection lens mounted thereon, a fan disposed in the head body, and a fan frame mounted on a prism bearing face at a plurality of points so as to hold the fan. The fan frame has a face that faces the prism bearing face and is shaped substantially like a quadrangle in outline, and one of the two diagonal lines of the quadrangle extends along the plane orthogonal to the prism bearing face. This makes it possible to mount the fan frame close to the projection lens side, and to thereby promote size reduction.

Abstract: A light source device or a projection type display apparatus has a pillar optical element; a condenser means; and a first lens effective to focus the image of the emitting end face of the pillar optical element at a surface to be irradiated; wherein the pillar optical element includes a tapered portion on a side of the incident end face and a non-tapered pillar portion on a side of the emitting end face, a cross-sectional area of the tapered portion continuously increasing from the incident end face toward the emitting end face and a cross-sectional area of the non-tapered pillar portion being constant.

Abstract: A projection-type display apparatus includes a light source, a liquid crystal panel, and a light path changing element arranged between the light source and the liquid crystal panel for changing a light path so that a light beam emitted by the light source and going to the central portion of the liquid crystal panel is bent toward the peripheral portion of the liquid crystal panel. Therefore, a uniform illuminance distribution and a uniform color distribution are ensured.

Abstract: A projection ornament, which includes a lens having a first side that admits light and a second side that reflects light, a light permeable element, which can be a transparent film having a design printed on it or a transparent resin disk having a sculpture embedded in it, adhered to the first side of the lend, and a light source controlled to emit light through the light permeable element into the first side of the lens, enabling the image of the design or sculpture in the light permeable element to be seen through the second side of the lens.

Abstract: A projection type display apparatus is provided in which a polarizer is arranged on the light output side of the light valve. A stationary frame plate may be glued and fixed to a light incident surface of a dichroic prism of a projection type display apparatus. A frame plate holding a liquid-crystal light valve may be fastened to the stationary frame plate through an intermediate frame plate using screws. A light output side polarizer may be arranged inside an opening of the stationary frame plate and glued and fixed to the light incident surface of the dichroic prism. This construction may prevent the size of the apparatus from increasing and may restrain temperature rise in the light valve.

Abstract: A single display assembly (10) has an electronically controllable display (11) with a plurality of display elements (12) and sandwiched by two support plates (13,14), two polarizers (15,16) and two selective reflectors, namely a first selective reflector (17) and a second selective reflector (18). Support plates (13,14) and polarizers (15,16) are transparent media to permit passage of light. Selective reflectors (17,18) are holographic reflectors that are each pre-recorded with characteristics that includes a range (19 or 20) of predetermined incident angles relative to inward facing horizontal surfaces (24,25) and an angular transparency range (not shown) for passage of light. Assembly (10) has two opposite sides (21,22) to view indicia provided by display elements (12). Indicia can be selectively viewed from either of sides (21 or 22) without interference from external background of a remaining one of sides (21 or 22).

Abstract: A picture display apparatus and a cooling apparatus used for an optical apparatus for efficiently cooling sections to be cooled through the effective use of air currents supplied from a cooling fan, where in external wall and an internal wall of an air guide section guide rotating air currents generated by the cooling fan to intakes without reducing the air velocity by regulating and directing the air currents in accordance with the shape of the cooling fan and the direction of rotation of the fan. The air currents passing through the air guide section are taken through the intakes into an optical unit and sent to the sections to be cooled including a light valve and a polarizing plate for each color. The sections are thus cooled by the air currents.

Abstract: An image display apparatus includes an arc lamp as a white-light source, an ellipsoidal mirror for collecting a light beam from the arc lamp, a color filter for producing sequentially three primary colors of light from the white-light beam, a condenser lens for transmitting a light beam transmitted through the color filter, and a single spherical mirror or non-spherical mirror for reflecting the light beam transmitted through the condenser lens. The image display apparatus further includes a digital micromirror device. This device receives the light beam reflected from the reflecting mirror and produces on and off states by varying the tilt of a micromirror of each of a number of two-dimensionally arrayed pixels to vary the angle of reflection of the light beam reflected therefrom. From there, a projection lens enlarges and projects the light beam reflected from a pixel.