Abstract: A display apparatus of the projection type is improved in that, when a lamp valve breaks or is to be replaced, glass fragments and so forth thereof are prevented from being scattered into the inside of an outer housing of a projector apparatus through a cooling air intake port in a portion of the outer casing below the lamp valve and a comparatively small number of cooling fans are used to reduce the size and the weight of the overall display apparatus while optical modulation elements, a light source element and so forth can be forcibly cooled in a high efficiency. Cooling air blasted from an air blasting fan is blasted through an air blasting duct to three spatial optical modulation elements, a PS conversion element and a discharge lamp to forcibly air-cool the elements. A lamp box in which the light source is accommodated and which is removably mounted in an outer housing has a cooling air intake port through which cooling air is taken in to the light source.

Abstract: A projector having a first housing, a second housing, a projector mainframe, a lamp module and a connector pair is disclosed. The removabl lamp module is installed in the first housing which forms part of the projector housing. The projector mainframe is enclosed in the second housing which forms the other part of the projector housing. The connector pair comprises a first half connector and a second half connector, which can be fixed to or separated from each other. The first half connector connected to the lamp module is movable with respect to the second half connector fixed to the projector mainframe. When the first and second half connector are mechanically coupled, the lamp module is then mechanically coupled with the projector mainframe such that the projector can be successfully assembled.

Abstract: A liquid crystal display projector for projecting images on a screen. The projector includes a projector body and an optical projection system positioned generally within the projector body. A releasable first self-aligning lamp socket for receiving a first end of a longitudinal replaceable bulb and a releasable second self-aligning lamp socket for receiving a second end of a longitudinal replaceable bulb are mounted on a hinged platform coupled to the projector body. The platform has a first position where the platform swings the bulb outside of the projector body and a second position where the platform swings the bulb into an interior position inside the projector body optically aligned with respect to the optical projection system.

Abstract: The present invention is a system and method to quickly and accurately measure the luminance and luminance distribution of a light on the surface of an object so that the position of the lamp can be adjusted relative to the projector optics to obtain the best luminance available for that object. A scanning light receiver, which produces an optical image of the object whose luminance is to be tested, is set up so that it may view a substantial portion of the surface of the object. The light receiver is connected to a analyzer and control unit ("ACU") to which it sends an electronic image representing the reflected luminance of the surface during each scan. The reflected light that is detected by the light receiver is then analyzed by the ACU to determine the luminance levels and distribution across a substantial portion of the surface by measuring the voltage of each pixel detected by the light receiver measured against the voltage produced by a black level.

Abstract: A light source for use in a liquid-crystal rear projector serving as a projection apparatus can be changed from a front to thereby improve a performance of the apparatus. The liquid-crystal rear projector serving as the projection apparatus includes a light source accommodating portion provided at a front for accommodating therein a lamp house having a lamp light source, the lamp house being of a cartridge type accommodated in the light source accommodating portion, and a handling portion disposed at a front of the accommodated lamp house for explaining how to exchange the lamp house.

Abstract: A liquid crystal projector is provided which features easy lamp replacement, accurate detection of liquid crystal cell temperature, and easy assembly and maintenance, the illumination source either being installed on a first illumination source support or installed on the second illumination source support and an illumination source support spring. A unit consisting of the illumination source installed on the first illumination source support is held between the second illumination source support and the illumination source support spring which are mounted on the main frame structure. A polarizer and a liquid crystal cell are held between a support which has a hook and a catch, a temperature detector installation part for installing a temperature detector which detects the temperature of the liquid crystal cell being provided on the support. A holder is used to cause the temperature detector to make contact with the liquid crystal cell of the liquid crystal projector.

Abstract: Multipurpose projector having a detachable projecting unit including a body having a sheet of transparent glass disposed in the top part thereof and an attaching recess at one side of an optical system region therein; a projecting unit attachable into the attaching recess or disposable right over the transparent glass by means of rotatable post attached to the body at the user's option; a liquid crystal display projector part having a light source disposed movably in a vertical direction in rear part of the optical system in the body, a first focusing lens for focusing the light emitted from the light source, a liquid crystal panel for receiving light focused by the first focusing lens, and a zoom lens; an overhead projector part disposed in the optical system in the body having a second focusing lens, a plurality of total reflection mirrors for deflecting a path of the light focused by the second focusing lens at a right angle from a horizontal direction to a vertical direction, and a Fresnel lens detachably

Abstract: The present invention permits easy and safe replacement of a lamp, improves stability of a video projector, and provides a compact and lightweight video projector.A projector driving battery is mounted in a battery mounting section formed in the bottom of a cabinet of a video projector. Therefore, the heavy battery is located in tile bottom of the cabinet. This further stabilizes the video projector. A lamp unit is mounted on a lamp mounting section formed in the back of the cabinet. When the lamp unit is mounted, a power output terminal in the cabinet is connected with a power input terminal of tile lamp unit at the same time. Thereby, when a lamp is replaced, it is unnecessary, unlike conventionally, to open and close a cover or electrically couple the lamp. Specifically, lamps can be changed merely by dismounting and mounting lamp units. Furthermore, a spare lamp unit 20 can be used as a lens cap.

Abstract: A lamp changing system is an LCD projector, comprising a reflective facet, a rotary plate having a plurality of arc-tubes and blocks disposed thereon, and a cam member having an upper cam and a lower cam, whereby upon rotating the cam member, an old arc-tube is separated from and new arc-tube is replaced for the old arc-tube as a light source for the LCD projector.

Abstract: A device for simulating an image formed of light and shadow created by sunlight over a period of time includes a mask having a substantially opaque portion and a light source for shining light through the mask. The image moves to realistically simulate the effect created by the sun shining into a room through an exterior window. In one embodiment, the device includes a filter bearing a translucent color gradient so that the light defining the created shadow has a changing hue.

Abstract: An overhead projector is provided with two lamps arranged in an angular relationship on a frame having a single pivot point to cause the lamp not in use to be out of the path of air flowing to the lamp in use within the projector. The pivot point may coincide with a lead screw which would permit axial movement of the lamps in addition to rotational movement to correct for undesirable color effects.

Abstract: A drawing production aide is disclosed which is designed to be placed over a working surface where an artist, engineer or architect is drawing. The device includes a carrier for a drawing and a light and lens system designed to project the drawing on the working surface. In a further aspect, the inventive aide includes an adjustable grid device designed to be used to visualize a scene in terms of a plurality of subsections, to best facilitate drawing the scene.

Abstract: A lamp changer for use with a slide projector having a projection lens and a removably modular projection lamp unit insertable through an access door opening. The lamp changer has a housing releasably connectable to the projector at the access opening and a lamp holder for holding at least two projection lamps. The lamp holder is mounted in the housing for pivotable movement about a first axis to successively position each lamp in the lamp holder in direct alignment with the projection lens. Movement of the lamp holder is effected when desired and the new lamp is moved into alignment with the lens and is energized.

Abstract: A linear switch assembly comprises a planar plate secured to the inner wall of a housing for a light source. A carriage member has a first slot positioned within the edge of the plate member and a second shorter slot on a top adjacent surface. The plate has an extending rigid rod positioned within the second slot to allow the carriage to move along the plate member in a linear direction. Associated with the carriage member are first and second lamp assemblies each having an associated actuatable switch. As the carriage is moved the rod coacts with an operating lever associated with each switch to actuate the switch when the associated lamp assembly is moved into a proper position whereby power is supplied to each lamp assembly only when at the proper operating position.

Abstract: A disclosed projector includes a condenser lens, a plurality of light source means having different focal lengths and disposed around the condenser lens, a projecting lens with an adjustable distance from the condenser lens, and a stage glass located between the condenser and projecting lens for carrying a transparent positive thereon. Depending on the size of the transparent positive, one of the light source means is selected and the distance between the condenser and projecting lens is adjusted, so as to project an image of substantially fixed magnitude with a constant brightness regardless of said size of the transparent positive.

Abstract: A filmstrip viewer/projector unit includes two separate projection lenses, one for front projection on a remote screen and the other for rear projection on a small local viewing screen built into the unit. A film carrier has two separate apertures therein respectively disposed in optical alignment with the two projection lenses for cooperation therewith to define first and second optical axes. A lamp directs a beam of light to a plane mirror disposed between the lamp and the film carrier and movable between two positions for respectively reflecting the beam of light along the first and second optical axes, respectively for projecting the film image onto the associated remote and local screens. First and second condenser lenses are respectively disposed along the optical paths between the reflector and the film carrier. The projection lenses share a common focusing mechanism.

Abstract: An illumination control apparatus for a device for projecting images at a variable magnification, comprises a light source unit for illuminating an object and a condenser lens unit at least one of the units being movable along the optical axis of projection, with the power supply to the light source unit being varied with such movement. When the magnification of projection of the device is varied, at least one of the units is shifted with a variation of the power supplied to the light source to provide a constant illumination and a uniform distribution of illuminations to the plane of the projected image of an object irrespective of a variation in the projection magnification.

Abstract: A hand held microfilm reader wherein the film is maintained within the reader housing and the controls for positioning the film are easily manipulated by one hand. An optical system provides an intense automatically focused image projected onto a screen for viewing by the user. The light source is a conventional lens end bulb that has been rendered uniformly directional by its having been mounted in pre-aligned relationship with respect to a clip which is configured to be precisely registered with remaining portions of the optical system.

Abstract: Disclosed is a mechanical translation linkage and lamp support apparatus for maintaining the projection light source inside a gimballed transparency displaced from the geometric center of the transparency and in a fixed spatial relation with the center of the transparency as the transparency rotates about any of its three mutually perpendicular axes. The translation apparatus employs only a mechanical linkage to ground and reacts to rotation of the support gimbal about either the X or Y axis to maintain the projection light source at the required position regardless of the attitude of the gimbal.

Abstract: A projector for a film transparency having a first housing for enclosing an image transmitting system and a second housing having an open end through which the illumination from a projection bulb supported within the second housing is adapted to pass. The first and second housings are adjustably coupled to each other such that when they are located in juxtaposed position the illumination from the bulb is directed into the first housing so as to project an image of the transparency film along an optical path defined by the transmitting system onto a rear projection screen mounted in one wall of the first housing. When the two housings are spaced from each other, the illumination from the lamp may be advantageously utilized for nonphotographic purposes, e. g., reading. Preferably, the rear projection screen is pivotally mounted to the first housing such that it may be moved out of alignment with the optical path thereby enabling the image to be projected onto a remote viewing surface.

Abstract: A switching device for a projection lamp of a projector wherein an electrical control device, which is separated from the projector and which supplies the projector lamp with electrical energy, is controllable from the projector by a control device via at least one control connection disposed on the projector.FIELD OF THE INVENTIONThe invention relates to a switching device for a projection lamp, especially a gaseous discharge lamp, which needs a relatively large electrical control unit that normally is separated from the projector.BACKGROUND OF THE INVENTIONSuch a device is known from U.S. Pat. No. 3,039,022. With this device it was disadvantageous that all control functions were carried out by means of the electrical control unit, so that the transmission of control commands from the electrical control unit to the mechanical parts of the projector had to be effected by means of relatively expensive magnets.

Abstract: A microfiche reader according to the present invention includes a housing consisting of a hood portion and a base portion, a screen located within the hood portion and visible through the front end of the hood, a combined microfiche carriage and index holder, a lens assembly and a projection system. The combined microfiche carriage and index holder serves to accurately locate the microfiche with respect to the index grid. By reason of the fact that there is no relative movement between the index grid and the microfiche in use, it is always possible to accurately locate the microfiche with respect to the projection system by reference to the index grid. The index grid is illuminated by an index illuminating lens carried by the housing. The illuminating lens is located in a fixed relationship with respect to the projection path which again contributes to the facility with which the microfiche may be accurately located in the projection path.

Abstract: A microfiche reader providing varying optical paths of projection of a microfiche image. Variable hood means provide self-contained viewing, or projection of the image on a screen, wall or ceiling. The light source for the reader may be removed and readily replaced without the operator touching the sensitive lamp. Dual image forming floating lenses having a universal focusing system provide multiple magnification capabilities with uniform focusing in all positions of the microfiche. Additional means prevent chipping of the glass plates holding the microfiche when the floating lenses are removed from contact with the glass plates.

Abstract: A microfiche reader providing varying optical paths of projection of a microfiche image. The light source for the reader may be removed and readily replaced without the operator's touching the sensitive lamp. Dual image forming, floating lenses having a universal focusing system provide multiple magnification capabilities with uniform focusing in all positions of the microfiche. The focusing system is self-compensating for mechanical tolerances. Additional means prevent chipping of the glass plates holding the microfiche when the floating lenses are removed from contact with the glass plates.

Abstract: A compact optical bench type unit for making selected color-component records of color transparencies for use in color printing comprises a light source with a rotary filter disc for directing a beam of selectively colored light through a light condenser which converges the beam through a color diapositive to be reproduced and into the objective of a camera. The condenser, possibly formed of Fresnel lenses, is of large dimensions to accommodate large diapositives, and the camera objective has a relatively short focal length. Chromatic aberration of the condenser is corrected by moving the light source in correspondence with rotation of the filter disc, or by selectively inserting correcting lenses in the beam.

Abstract: A navigational apparatus for use in a piloted craft in which a map is displayed pictorially on a screen, representative of the terrain over which the craft is passing. The apparatus employs a moving film strip, a light source and known means to focus and project an image onto the screen. The light source is adapted for arcuate movement across the width of the film synchronously with an optical scanning device placed between the film and the screen and also adapted for arcuate movement so that N-S scanning of an individual film frame may be effected. E-W scanning of the film frame is effected by advancing the film in a suitable film transport. The film transport mechanism is suitably programmed to take into account a correction factor for the arcuate displacement of the N-S scanning device.

Abstract: In order to compensate for the "Keystone-effect," a still projector is equipped with a vertically adjustable lens holder, which is coupled by a sliding pivot to a pivotable lamp housing. The lamp housing has a pair of arms projecting therefrom, which have slots extending therein which, in turn, register with pins positioned in the lens holder. The pins are located adjacent the rear nodal plane of the lens, and are aligned with an axis, which intersects the optical axis of the lens. Upon adjusting the holder vertically, the lamp housing will tilt to insure that the projected image will angularly conform to the original.