Abstract: In a liquid crystal projector provided with a cooling fan, the liquid crystal projector comprises a plurality of temperature sensors for detecting the internal temperature of the liquid crystal projector and a fan control circuit for controlling a driving voltage for the cooling fan on the basis of a temperature detected by each of the temperature sensors, the fan control circuit comprising means for calculating, on the basis of the temperature detected by each of the temperature sensors and a temperature range determined depending on the position where the temperature sensor is mounted, the ratio of the detected temperature to the temperature range for the temperature sensor; and means for controlling the driving voltage for the cooling fan on the basis of the maximum of the ratio of the detected temperature to the temperature range which has been calculated for each of the temperature sensors.

Abstract: A liquid crystal projector provided with one or a plurality of cooling fans comprises a temperature sensor for sensing the internal temperature of the liquid crystal projector, and a driving control circuit for controlling the driving voltage of the cooling fan on the basis of the temperature sensed by the temperature sensor. A driving control circuit controls the driving voltage of the cooling fan in proportion to the temperature sensed by the temperature sensor in a case where the temperature sensed by the temperature sensor is within a predetermined range.

Abstract: A projection display apparatus having a light source for generating a white light, a liquid crystal panel for modulating an incident light from the light source, a polarizing plate which is located at a light exiting side of the liquid crystal panel for polarizing a light from the liquid crystal panel passed therethrough and a cooling liquid for cooling at least the liquid crystal panel and the polarizing plate. A projection lens device having plural lens elements which is located at a light exiting side of the polarizing plate is provided for projecting the light passed through the polarizing plate. One of the plural lens elements located nearest the polarizing plate has a negative refractive power in a center region containing an optical axis thereof and has a positive refractive power in a peripheral portion of the center region.

Abstract: A projector changes stepwise electric energy supplied to a light source based on temperature information which is detected by a temperature sensor. The temperature sensor detects the temperature of components of an optical engine or an ambient air temperature. A lamp output control circuit changes stepwise the electric energy supplied to the light source based on the temperature information detected by the temperature sensor.

Abstract: A projector has a housing, a light source positioned within the housing to generate light, a fan positioned beside the light source to dissipate heat generated by the light source, and an air vent positioned beside the fan to guide heat out of the housing. The air vent reduces turbulence, and thus noise, by the addition of at least one guiding rib. The guiding rib causes heat to flow fluently through the air vent and out of the housing.

Abstract: A lamp house prevents danger when a lamp bulb, acting as a light source in a housing, breaks. The lamp house includes, at inlet and outlet vents for cooling the lamp bulb, movable plates which are movable only toward the inside of the housing of the lamp house. Springs for closing the movable plates are provided and a sensor for detecting opening and closing states of one of the movable plates is disposed on the side of the inlet vent.

Abstract: The projection type display apparatus has liquid crystal panels with polarizers, a light source, a power supply, and a ballast. A cooling device is arranged in the apparatus such that a first set of cooling fans blow cooling air to cool the liquid crystal panels and the polarizers, and a second set of cooling fans suck the cooling air passing through the liquid crystal panels and the polarizers and blow the cooling air to independently cool the light source, the power supply, and the ballast. Therefore, a projection type display apparatus with little light leakage and low noise can be realized. The invention also provides a cooling unit, for the light source, which includes a movable lamp house and a duct with a cooling fan.

Abstract: A projection display device includes an optical unit, a cooling fan for cooling the circumference of light valves of the optical unit, and an exterior cabinet accommodating the optical unit and the cooling fan. The cooling fan is in the form of a sirocco fan. Cooling air of the cooling fan is brought to the circumference of the light valves through a duct, and is distributed by air-quantity controlling means arranged in the duct for effective cooling thereof.

Abstract: A fan assembly for an image projector includes a split fan shroud that substantially surrounds the fan but does not fully enclose it. The fan shroud has a height that is substantially equal to the height of the fan. In one embodiment the shroud includes opposed first and second sections that are separately mounted to the image projector. In another embodiment the shroud is integral with a portion of the image projector housing.

Abstract: A power supply unit is formed so as to be divided into first and second power supply blocks, which are disposed on both sides of a projecting lens. This allows the power supply blocks to be efficiently disposed in a projection display device, so that dead space is not easily formed in the projection display device, making it possible to reduce the size of the projection display device. First and second power supply block cooling paths are formed at first and second power supply blocks which are liable to generate heat, respectively. A light modulating system cooling path is formed at a light modulating system disposed at substantially the center of the projection display device. Therefore, even when these component parts are closely disposed in the projection display device of a compact size, proper cooling operations can be carried out, making it possible to cool the entire projection display device more efficiently.

Abstract: A display apparatus having a reflecting type light valve which has a light incidence/reflection surface, a drive circuit which drives the reflecting type light valve by supplying an image signal, a cooling system which cools at least the reflecting type light valve with cooling fluid, and a partition wall which partitions a space in the display apparatus into a cooling fluid side and a light incidence/reflection side. The reflecting type light valve forms a part of the partition wall, and the light incidence/reflection surface faces the light incidence/reflection side and a part opposite to the light incidence/reflection surface of the reflecting type light valve is cooled by the cooling system.

Abstract: A projector capable of throwing image on a screen from objects, the project comprising a base including a plurality of mirrors, a rear slanted plate hinged to the base, a lens in the front board, an object receiving drawer, and a cover; an angle adjustment means on the outside of the rear slanted plate; a light source; a housing shaped; and a cooling means. Image of object is reflected on mirror and lens. A clear image is obtained by turning the focusing knob. Further bias the rear slanted plate for adjusting the angle of thereof so as to obtain a better angle of the lens for enhancing focus.

Abstract: In a display unit wherein an optical block is disposed inside of a housing having a screen at its front, and an image light from the optical block is projected on the screen, a display unit in which the housing is made a closed structure and a path is provided for circulating air between the housing and the optical block so that dust is prevented from entering inside of an apparatus and attaching to optical parts, and at the same time, heat generated in the apparatus can be sufficiently cooled.

Abstract: In a liquid crystal projector provided with a cooling fan, the liquid crystal projector comprises a plurality of temperature sensors for detecting the internal temperature of the liquid crystal projector and a fan control circuit for controlling a driving voltage for the cooling fan on the basis of a temperature detected by each of the temperature sensors, the fan control circuit comprising means for calculating, on the basis of the temperature detected by each of the temperature sensors and a temperature range determined depending on the position where the temperature sensor is mounted, the ratio of the detected temperature to the temperature range for the temperature sensor; and means for controlling the driving voltage for the cooling fan on the basis of the maximum of the ratio of the detected temperature to the temperature range which has been calculated for each of the temperature sensors.

Abstract: An optical equipment having a discharge lamp for supplying light, and first, second and third light valves for projecting the light from the equipment, having an air intake opening arranged on one side of the equipment, a ventilation device associated with the air intake opening so as to draw in air from outside of the equipment through the air intake opening and a ventilation path arranged between an outlet of the ventilation device and the first, second and third light valves. The ventilation path includes a plurality of partition members which divide the ventilation path into first, second and third air flow paths so as to cool the first, second and third light valves respectively by air from the ventilation device.

Abstract: A projector includes an enclosing structure that encloses an optical path from an electrooptical device to a projection lens with a heat insulating member, and a thermoelectric transducer for cooling air inside the enclosing structure. Since the enclosing structure is formed by the heat insulating member, the electrooptical device can be efficiently cooled while thermally blocking between the inside and the outside thereof. Since being enclosed, the entry of dust or oil mist from the outside is prevented, and dust or oil mist does not adhere to the electrooptical device and the like.

Abstract: An optical equipment having a discharge lamp for supplying light and a light value device for projecting the light from the equipment having an air intake opening arranged on one side of the equipment. A ventilation device is associated with the air intake opening so as to draw in air from outside of the equipment through the air intake opening and a ventilation path, including a plurality of air flow paths which are independent, respectively, and arranged from an outlet of the ventilation device to the light valves continuously. Ventilated air flows through the air flow paths so as to cool respectively different parts of the light valve device.

Abstract: A projection display includes a projection lens and first and second light modulators on three sides of a color recombination unit. First and second blower units are respectively disposed on two sides of the projection lens for cooling the light modulators.

Abstract: This invention concerns reducing fan noise and preventing a light source, an optical element, and the like from deteriorating in a projector display device. The projection display device includes a light-source lamp unit, an optical system unit having a modulation device, a projection lens for enlarging and projecting an image formed by the optical system, a power supply unit for supplying electric power for driving the device, power supply intake fans, a modulation device intake fan, and exhaust fans. Fan noise can be reduced by driving only the power supply intake fans for a predetermined period after the device is powered on. Furthermore, the light-source lamp, the optical elements, and the like can be prevented from deteriorating by controlling the rotation speeds of the other fans based on detected temperatures detected by temperature sensors.

Abstract: A power supply unit is formed so as to be divided into first and second power supply blocks, which are disposed on both sides of a projecting lens. This allows the power supply blocks to be efficiently disposed in a projection display device, so that dead space is not easily formed in the projection display device, making it possible to reduce the size of the projection display device. First and second power supply block cooling paths are formed at first and second power supply blocks which are liable to generate heat, respectively. A light modulating system cooling path is formed at a light modulating system disposed at substantially the center of the projection display device. Therefore, even when these component parts are closely disposed in the projection display device of a compact size, proper cooling operations can be carried out, making it possible to cool the entire projection display device more efficiently.

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 display device, such as a reflecting type liquid crystal projector, in which dust is prevented from becoming attached to a reflecting type light valve, such as a liquid crystal panel, and an improvement in cooling effect are attained. The device has a structure having a partition wall for forming an enclosed space including at least an incidence/emission optical system of the reflecting type light valve. The reflecting type light valve is provided in the partition wall such that a light incidence/emission surface of the light valve faces into the side of the enclosed space. A part opposite to the light incidence/emission surface of the reflecting type light valve faces outside the enclosed space. In a structure where a cooling arrangement or a thermal conductive partition wall is connected to the part opposite to the light incidence emission surface, the cooling effect is further improved.

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: Disclosed is an image projection apparatus including a display device which has a plurality of pixel apertures and displays image information, an illumination optical unit for illuminating the display device, a projection optical unit for projecting the image information displayed on the display device on a predetermined surface, and a blower for blowing air to the atmosphere in the display device. Dust affecting a projected image is prevented from attaching near the display device.

Abstract: In a projection display provided with an optical unit, a power source unit, an external case to store the optical unit and the power source unit, a suction opening (75) is formed in one end part of the power source unit, a discharge opening (77) is formed in the other end part, and the suction opening (75) is arranged in the vicinity of an air inlet in the external case. Because the suction opening (75) and the discharge opening (77) are provided, the inside of the power source unit can be independently and efficiently cooled, and the optical unit and the power source unit can be arranged closely to each other.

Abstract: A liquid crystal projector provided with one or a plurality of cooling fans comprises a temperature sensor for sensing the internal temperature of the liquid crystal projector, and a driving control circuit for controlling the driving voltage of the cooling fan on the basis of the temperature sensed by the temperature sensor. A driving control circuit controls the driving voltage of the cooling fan in proportion to the temperature sensed by the temperature sensor in a case where the temperature sensed by the temperature sensor is within a predetermined range.

Abstract: The invention provides a projector capable of reducing costs and promoting miniaturization while also being dust-proof. A second sirocco fan with an air-inlet opposing a projection lens is used, and an air-inlet of an outer case is formed on a side face thereof. Thereby, it is difficult for dust to be sucked therein compared with an air-inlet formed on the bottom or top face of the outer case, enabling the projector to be dust-proof without any filter. Since the filter is not required, the number of parts is reduced, thereby reducing costs. Furthermore, the second sirocco fan is placed by utilizing a space under the projection lens, which is liable to be a dead space, enabling the arrangement space to be efficiently used thereby promoting miniaturization of a projector.

Abstract: The invention provides a projector capable of easily replacing and efficiently cooling a light source, and capable of facilitating a reduction in the size of the projector. An exhaust fan adjacent to a light source lamp is mounted to a replacement cover so as to be removed from the main body of the projector together with the replacement cover. For this reason, by only removing the replacement cover, the light source lamp can be easily attached and detached together with the replacement cover unit. In addition, since it is not necessary to separately secure a special space for sliding the replacement cover unit, other components except the exhaust fan can be disposed closely to the periphery of the unit, and the size of the projector can be further reduced. Furthermore, when the replacement cover is closed, the exhaust fan is positioned closer to the replacement cover unit, so that a light source device in the unit can be efficiently cooled.

Abstract: The invention provides a projector capable of cooling a light-source lamp efficiently and suppressing noises as well. In a first cooling system, the base side of a light-source lamp, which reaches a high temperature, is intensively cooled by a first sirocco fan. An axial-flow exhaust fan is provided close to the light-source lamp so that cooling air is allowed to quickly flow while cooling the light-source lamp. Therefore, even when the first sirocco fan, in which the air pressure of cooling air is liable to be reduced, is used, heat generated in the light-source lamp can be smoothly radiated, thereby efficiently cooling the light-source lamp. Since the first sirocco fan is remarkably quiet as compared to an axial-flow fan, noises are suppressed to a low level.

Abstract: A projector includes a duct having a connecting end for connection to an air inlet provided in a housing, and an air intake end for drawing in outside air for cooling the interior of the projector. The duct is made of a soft or flexible material and is capable of altering its shape. Thus, the duct can change the position of the air intake end in space, for example, to different positions. Further, the duct is pivotable on a pivot axis, and thus can change the opening direction of the air intake end circumferentially about the pivot axis. Therefore, selection of the position and/or opening direction of the air intake end so as to draw in the outside air suitable for cooling the interior depending on the usage forms of the projector achieves efficient cooling of the interior of the projector.

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: The present invention relates to a projection type display using a transmission type liquid crystal light valve and its object is to provide a projection type display which does not reduce the reliability due to the change of the working environment. A projection type display of the present invention comprises liquid crystal light valves 4R, 4G and 4B arranged in a body which modulate and emit an incident light form the lamp 2, fans 10 and 12 for cooling the inside of the body, a temperature detecting element 30 for detecting the temperature in the vicinity of the liquid crystal light valve 4G and a control unit 8 for controlling rotational frequencies of the fans 10 and 12 and for controlling on/off of a power source 26 of the lamp 2 based on a compensated temperature after compensating the temperature detected by the temperature detecting element 30 by a predetermined temperature compensation value T0.

Abstract: An optical equipment having a discharge lamp for supplying light, and first, second and third light valves for projecting the light from the equipment, having an air intake opening arranged on one side of the equipment, a ventilation device associated with the air intake opening so as to draw in air from outside of the equipment through the air intake opening and a ventilation path arranged between an outlet of the ventilation device and the first, second and third light valves. The ventilation path includes a plurality of partition members which divide the ventilation path into first, second and third air flow paths so as to cool the first, second and third light valves respectively by air from the ventilation device.

Abstract: A lamp house for appropriately preventing danger when a lamp bulb breaks up includes, at a vent hole for cooling the lamp bulb as a light source provided in a housing, a movable plate which is movable only toward the inside of the housing of the lamp house, a spring for closing the movable plate and a sensor for detecting opening and closing states of the movable plate disposed on the side of an air inlet of the vent hole.

Abstract: In optical equipment, such as a liquid crystal projector, a discharge lamp supplies light through a light valve device to project a light beam on a screen. A cooling system is provided to cool the light valve device, including a ventilation device, such as a centrifugal fan, for drawing in air through an air intake opening in the case of the optical equipment and an air flow path for supplying the drawn in air to the light valve device along plural paths. For this purpose, guide members are provided in the air flow path to divide and direct the air flow to individual parts of the light valve device along the plural paths.

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 order to prevent dust from sticking to the LCD panel, to prevent the LCD panel from being heated and to suitably adjust the position of the LCD panel, a duct is provided between cooling means for a light source and cooling means for a LCD panel to send cooling air from the LCD panel side to the light source side. Therefore, a light incidence/reflection plane of the LCD panel is disposed in an almost hermetically closed space and an optical path from an integrator lens to the LCD panel is formed in the almost hermetically closed space.

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 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: A liquid crystal projector, comprising: a liquid crystal panel; a light source for irradiating light onto an image formed on the a liquid crystal panel; a projection lens for enlarging and projecting the image projected from the liquid crystal panel; a cooler, such as a suction fan, for sending cooling air flow onto a panel surface of the liquid crystal panel; an air velocity sensor for sensing air velocity of the cooling air flow sent onto the liquid crystal panel; and a protection device for protecting the liquid crystal panel on a basis of a detected value of the air velocity measured by the air velocity sensor. The is further formed an air passage for passing the cooling air flow along with the panel surface of the liquid crystal panel, and the air velocity sensor is positioned in an exit portion of the cooling air flow passing through the liquid crystal panel.

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: The internal space of the optical lens unit (9) of the projection display apparatus (1) 1 is made substantially airtight by means of the light guides (901, 902) defining the outside surface thereof, the top seal plate (991) mounted to the top thereof, the bottom seal plate (1150) mounted to the bottom thereof, and the front head panel (903) thereof. Inside this internal space an air circulation current (1180) circulating vertically is created by means of the circulation fan (15B) disposed between the liquid crystal light valves (925R, G, B) and bottom seal plate (1150). While this air circulation current (1180) flows over the bottom of the top seal plate (991), heat is dissipated to the outside air introduced to the top surface thereof, and while it passes the air paths (1160, 1170) routed through the vent hole in head panel (903) over the radiators (5R and 5L) formed in the front case, heat is dissipated to the outside.

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: A rear projection type image display apparatus having an arrangement that a projection distance of a projection lens thereof is shortened and a density of mounting of parts relating to an optical system and an electric system is made higher. Furthermore, a width of a rear portion of a housing of the rear projection type image display apparatus is reduced rearwards at any position from the upper portion to the lower portion thereof, and the lower portion of a back cover is depressed inwards. Thus, a space required to install the rear projection type image display apparatus can be reduced, the rear surface of the apparatus can be disposed on a wall without any gap when the apparatus is installed along the wall, and the overall body of the apparatus can be received deep into a corner of walls when the apparatus is installed at the corner.

Abstract: Projection display apparatus 1 includes light source lamp unit 8, optical lens unit 9, projection lens unit 6, and power supply unit 7. Projection lens unit 6 is disposed in the front part of outside case 2, light source lamp unit 8 is disposed in the back part of the outside case of the apparatus, and between these units 6 and 8 optical lens unit 9 and power supply unit 7 are disposed in a vertically stacked arrangement with optical lens unit 9 on the top and power supply unit 7 on the bottom. Because these large units 9 and 7 are vertically stacked, the front-back and right-left dimensions (i.e. length and width) of the overall apparatus can be reduced. An apparatus 1 that is easily portable and does not require a large installation space can therefore be achieved. Because the heavy power supply unit 7 is on the bottom, apparatus 1 is also stable when placed on a table, etc.

Abstract: Disclosed is a projection type liquid crystal display device. The device comprises a light source; collimator elements; a liquid crystal panel which produces an image; a light path wall which defines a closed space and which surrounds and supports at least one of the collimator elements and the liquid crystal panel; a projection lens; and a screen. The light path wall is provided with a heat dissipation promoter on the outer surface thereof.

Abstract: A liquid crystal panel unit and a liquid crystal projector incorporating the liquid crystal panel unit. The panel includes a metallic sealed container with a light-transmissive window, a liquid crystal panel accommodated in the sealed container so as to allow light being transmitted to leave the light-transmissive window, and a fan accommodated in the sealed container so as to be spaced from the liquid crystal panel. The liquid crystal panel unit can reliably cool the liquid crystal panel, without any deterioration in the image quality due to dust. A liquid crystal projector using the liquid crystal panel unit is also provided.

Abstract: The present invention includes a projector illumination system having a light source positioned between a condenser lens and a light-collecting reflector. The light source includes a bulb that is urged under compression against a surface of the condenser lens. The condenser lens receives a flow of cooling air over a surface opposite that against which the light source is in contact to minimize deformation of the condenser lens caused by heat emanating from the light source.

Abstract: Projection display apparatus 1 includes light source lamp unit 8, optical lens unit 9, projection lens unit 6, and power supply unit 7. Projection lens unit 6 is disposed in the front part of outside case 2, light source lamp unit 8 is disposed in the back part of the outside case of the apparatus, and between these units 6 and 8 optical lens unit 9 and power supply unit 7 are disposed in a vertically stacked arrangement with optical lens unit 9 on the top and power supply unit 7 on the bottom. Because these large units 9 and 7 are vertically stacked, the front-back and right-left dimensions (i.e. length and width) of the overall apparatus can be reduced. An apparatus 1 that is easily portable and does not require a large installation space can therefore be achieved. Because the heavy power supply unit 7 is on the bottom, apparatus 1 is also stable when placed on a table, etc.

Abstract: A video projection system having a liquid crystal panel with a video image, a projection lamp with ON/OFF control, a zoom lens with a zoom control mechanism, a focusing lens with a focusing control mechanism, an audio system with a volume control, a projection-lamp light detector, a heat sensor, a variable-speed cooling fan, a control module having a microprocessor and a digital-to-analog converter, a display, a keypad, an alarm/annunciator, a power supply with ON/OFF control, and an infrared based remote control system able to control power ON/OFF, zoom, focus, picture, and sound volume.