Abstract: A projector with air cleaning functionality is equipped with a negative ion generator. The negative ion generator is positioned along a cooling airflow route of the projector and is adjacent to a lamp module. A photo-catalyst sheet, which is stimulated by ultraviolet light emitted from the lamp module, can produce the negative ions quickly. The air, which is circulated along the cooling airflow route, carries the negative ions out of the projector so as to clean air in the surroundings.

Abstract: According to one embodiment, a lamp unit comprises a light source lamp, a casing and a dividing member. Configured to hold the light source lamp, the casing comprises a first opening as an inlet port where cooling air is fed from the outside to the light source lamp. The dividing member is provided in the vicinity of the second opening of the casing and is configured to divide the flow of the cooling air into the second opening into at least two paths.

Abstract: An object of the invention is to achieve a high intensity, a compact structure, a cost reduction and a heat radiation of a liquid crystal panel, in a projection type video display apparatus employing a combination of LED light sources and a light pipe. The light pipe is formed in a hollow type so as to be utilized as a cooling wind path. Further, a permeable or reflective baffle plate is provided within the light pipe. Further, the light pipe is formed by coating a mirror on an inner surface of an optical case integrally formed by fixing optical parts. Further, a dichroic mirror is arranged in an LED light source outgoing surface.

Abstract: A projection type display apparatus includes a housing having a first side having an air intake opening and a second side having an air exhaust opening, a light source for supplying light, and a light valve device which modulates the light output from the light source. A centrifugal fan is associated with the air intake opening so as to draw air from the air intake opening. A first ventilation path is coupled with the air intake opening so as to lead air flow from the air intake opening toward a lower portion of the light valve, and a second ventilation path is formed from the lower portion of the light valve to an upper portion of the light valve. An exhaust fan is associated with the air exhaust opening so as to draw out air flowing from the second ventilation path through the air exhaust opening.

Abstract: A projector having an optical engine, the optical engine including: an optical synthesizer; a plurality of display devices corresponding to the optical synthesizer; a plurality of light sources emitting light; a light guide plate provided between each light source and each display device; and a heat pipe contacting the light sources to reduce a temperature deviation between the light sources.

Abstract: An image projection apparatus includes a lamp, an optical modulator which modulates light emitted from the lamp to correspond to image data, a ballast which operates the lamp, a power supply unit, and a duct in which the power supply unit, the ballast, and the lamp are accommodated. The duct includes a first absorption hole and a main exhaust hole that communicate with an outside, and forms an air-flow path on which the first absorption hole, the power supply unit, the ballast, the lamp, and the main exhaust hole are disposed.

Abstract: With a trend toward a higher intensity projection type liquid crystal display device to further increase brightness of a projection screen, rated input power of a light source lamp increases, which makes essential a fan apparatus for cooling the light source lamp, etc. Such a fan apparatus would require a light-shielding member which causes the number of parts to increase. The present invention provides a fan apparatus provided with a rotor section that can be rotated/driven around a predetermined rotation axis and a propeller section including propeller blades and attached to the rotor section arranged in such a way as to substantially shield light parallel to the rotation axis.

Abstract: A projection apparatus is formed employing a solid state light source having either an associated or integrated sensor to monitor a thermal condition of a region of the solid state light source. The sensor is equipped to output a signal indicative of the thermal condition of the monitored region. In various embodiments, a controller is also provided to conditionally initiate one or more thermal management actions based at least in part on the thermal condition of the region as indicated by the signal.

Abstract: A time management section is configured to change an output voltage in accordance with a temperature change characteristic of a lamp allowed to cool down. For restart of the lamp after the turn-off of the lamp, the lamp is cooled by a fan before the operation of turning on the lamp when it is judged that the temperature of the lamp is higher than a predetermined value, based on the output voltage from the time management section. The lamp is immediately turned on without the cooling of the lamp by the fan when it is judged that the temperature of the lamp is lower than the predetermined value.

Abstract: A projection device is provided, wherein the projection device includes a casing, a plurality of electronic components mounted within the casing, a vent in the casing disposed substantially adjacent to an electronic component, and an injection molded, electrically nonconductive vent screen having one or more mesh portions substantially bordered by a peripheral frame, wherein the vent screen is detachably coupled within the casing and secured against the vent.

Abstract: A projection-type imaging device 1000 includes: a light source optical system 121 for emitting source light 122; image display elements 7a–7c each having a display surface 127 on which a plurality of micromirrors 301 are placed and driving the plurality of micromirrors 301 according to a control signal representing a prescribed image so as to reflect the source light 122 incident on the display surface 127 toward a first direction and a second direction differing from the first direction so as to obtain first light 10b and second light 10a, respectively; a prism 6 for transmitting the first light 10b and the second light 10a; a projection optical system 8 for projecting the first light 10b transmitted by the prism; an absorption section 19 for absorbing the second light 10b transmitted by the prism 6; and cooling sections 22, 23 and 24 for cooling the absorption section 19 by a liquid refrigerant 20.

Abstract: A partition installed in a housing of a projection apparatus to form a double-layer structure of a first zone and a second zone is used for a component of a cooling structure for the projection apparatus. Moreover, a first air inlet is disposed at the lower part of the first zone and a second air inlet is disposed between the first and the second zones. An air outlet with a duct and a plurality of sound sources and heat elements are disposed in the second zone. Outside air is drawn in from the first air inlet through a fan, then turned to enter the second zone through the second air inlet to cool heat elements and finally exhausted out of the system from the air outlet through the duct. Besides, the installments of the partition and the duct allow the distance of the sound source broadcasting to be lengthened and the diffusion light to be blocked so that both the noise and the leaking of the diffusion light can be reduced effectively.

Abstract: A projector projecting an image onto a screen, comprises a lamp emitting light; an optical system having an optical synthesizer including a blue panel, a green panel and a red panel, and an optical component disposed along an optical path from the lamp to the optical synthesizer; a cooling fan generating cool air cooling the optical system; and a guiding duct guiding the cool air to be distributed into a first passage and a second passage. With this configuration, the present invention provides a projector in which a guiding duct is partitioned and therefore cool air is distributed according to whether the cool air is sent to a relatively high temperature place or a relatively low temperature place in an optical system, preventing energy from being wasted by efficiently cooling some components of the optical system without overcooling others, and reducing noise caused by a cooling fan and air flow.

Abstract: An image projector comprises a discharge lamp, image projecting means for displaying an image on a screen by emitting light from the discharge lamp, electric power regulating means for regulating the electric power supplied to the discharge lamp, a cooling fan for reducing the temperature of the discharge lamp or the image projecting means, a cooling fan controlling means for controlling the rotation of the cooling fan, and a sensor for detecting a temperature of the discharge lamp or the image projecting means, wherein the rotation of the cooling fan is stopped when the image projector is in a standby mode. In the standby mode, the cooling fan controlling means controls the rotation speed of the cooling fan based on the detected temperature.

Abstract: A projector for projecting an image to an external screen in which an optical unit, includes rectangular liquid crystal panels disposed such that the short sides thereof are substantially parallel with a plane including principal light beams of the respective color light beams to be composited by a prism. Transmission cables are drawn out from the short sides of the respective liquid crystal panels, and a cooling fan is disposed such that the direction of cooling air is approximately parallel with the long sides of the liquid crystal panels.

Abstract: An electro-optical apparatus encased in the mounting case includes an electro-optical device in which the light emitted from a light source is incident on an image display region, and a mounting case including a plate disposed to face one surface of the electro-optical device and a cover to cover the electro-optical device, a portion of the cover abutting against the plate, wherein the mounting case accommodates the electro-optical device by holding at least a portion of a peripheral region located at the circumference of the image display region of the electro-optical device with at least one of the plate and the cover. In addition, the cover has a surface area increasing portion to increase the surface area thereof.

Abstract: There is a need for allowing an exhaust direction of a cooling air to be appropriately changed according to an installation environment of a projection type display device. There is another need to achieve a system for preventing an intake air and an exhaust air from being circulated therebetween by changing the direction of an intake port as well as an exhaust direction. A cooling system for an area around a lamp that accounts for a good part of an amount of heat generated by the projection type display device is isolated from a cooling system for other parts including a liquid crystal panel. Means is further provided of allowing the directions of intake and exhaust to be inverted in an entire device by changing the direction of rotation of an exhaust fan provided for the cooling system for the area around the lamp between forward and backward.

Abstract: An exhausting structure used in a rear projection TV has a ventilating chamber inside a casing of the TV to separate an optical engine from the casing. A fan is mounted in the ventilating chamber near the optical engine to ventilate the heat from the inside of the TV via a conduit and an outlet. The fan is isolated from outside of the TV to reduce any noise generated from the fan.

Abstract: An aspect of the invention provides a duct capable of cooling optical modulation systems with high efficiency while realizing miniaturization and reduction of the mounted number of cooling fans. The duct can be used for a projector including plural optical modulation systems, a dichroic prism, and a projection lens, and the respective optical modulation systems include liquid crystal panels, entrance side polarization plates, viewing angle correction plates, and exit side polarization plates. The duct can have plural air guide paths through which cooling air passes, a discharge opening, entrance side discharge openings, and exit side discharge openings formed in these air guide paths. With the optical modulation systems as targets of independent cooling, the entrance side discharge openings and the exit side discharge openings with respect to the targets of independent cooling are formed in different air guide paths.

Abstract: A projection display is provided according to one embodiment of the invention. The projection display includes a hollow case including a window opening, a screen formed on one portion of the case, and at least one mirror internally mounted to the case at a position to reflect light from the window opening to the screen. The projection display further includes a window mounted in the window opening. The projection display further includes an optical engine mounted to the case. The optical engine is positioned over the window and oriented so that emitted light from the optical engine is directed onto the at least one mirror. The projection display further includes a diaphragm internally attached to the case and dividing an internal volume of the case into a first portion and a second portion. The projection display further includes a gas filling the second portion of the case at an overpressure and a vent communicating with the first portion of the case and communicating with an external environment.

Abstract: Disclosed is a cooling structure for a projection television, which keeps the inside of the projection television clean and effectively cools the heated projection television. The cooling structure for the projection television comprises a heat blocking unit for separating a lamp system generating superheat from the sealed inner space, a cooling fan for forcibly cooling the heat generated by the synthesis system within the sealed inner space, the cooling fan being formed adjacent to the synthesis system, and a radiating unit for exhausting the heat of the inner space to the outside, the radiating unit being formed on the upper part of the housing.

Abstract: A projection television set having a screen and three projection units each capable of projecting a monochromatic image onto the screen. The projection units each having a cathode ray tube (CRT) optically coupled to a projection lens, which includes both a C-lens and a compound lens. A spacer preferably having three optical passageways is coupled to and between the CRTs and projection lenses such that three coolant chambers are formed. Preferably, the spacer includes fluid passageways that interconnect the coolant chambers. The spacer also includes coolant fill ports and reservoirs, zero pressure gum tanks seated in the reservoirs, and a plurality of heat exchanging ribs. Additionally, a fill port closure member preferably includes a push plug and packing sleeve. The plug and sleeve preferably include position retaining components and sealing components.

Abstract: An intake opening (132L) is formed on a left lateral side (132) of a lower cabinet (13) and an exhaust opening (132R) is formed on a right lateral side (132) in a rear projector (1), where a cooling air introduced from the intake opening (132L) by a plurality of fans provided in the lower cabinet (13) flows along a front side of a screen to cool the interior of the projector to be finally discharged from the exhaust opening (132R), so that the air after cooling the interior which is discharged by the exhaust opening (132R) is prevented from entering into the intake opening (132L), thereby always introducing fresh cooling air to cool the interior efficiently.

Abstract: A projector, which projects color images using the three liquid crystal panels (41-43) while cooling them by the fans (611-613) for G, R, and B panels, comprises the level calculation unit (711) for finding the intensity levels of the R, G, and B components of image signals, the level calculation unit (721) for finding the voice levels of voice signals, the fan control unit (73) for controlling the numbers of revolutions of the fans (611-613), and the memory (761) for storing the cumulative amount of lighting time of the lamp (21). As the intensity levels get higher, the numbers of revolutions of the fans are increased, and as the cumulative amount of lighting time becomes larger, the numbers of revolutions of the fans are decreased. As a result, unnecessary noises caused by the fans (611-613) can be reduced while the liquid crystal panels (41-43) are properly cooled.

Abstract: A rear projector (1) has a closed space (530) including an inside of an upper cabinet (12) and an electric optical device (44), where the electric optical device (44), a sirocco fan (541) located below the electric optical device (44), a duct (542) covering the upper side of the electric optical device (44) and a heat sink (543) attached to the upper cabinet (12) are disposed and an upper cabinet cooling system (600) that cools the interior of the closed space (530) in a circulative manner is provided in the closed space (530), thereby preventing invasion of duct etc. and providing high-quality image.

Abstract: A field sequential color display device includes a color wheel assembly. The color wheel assembly has a color wheel which is divided into a plurality of color regions and a motor for rotating the color wheel. The motor contains a sensor for detecting rotation of the motor and the sensor outputs at least one pulse per one revolution of the motor. The color wheel assembly also has a spatial light modulator for displaying image data that is driving in synchronization with the pulse output by the sensor.

Abstract: A projection television set having an enclosure housing a screen, an optical unit and a mirror, wherein the optical unit and mirror are capable of projecting an image onto the screen. The enclosure is preferably constructed from hollow plastic extruded panels. In addition, the enclosure preferably includes a duct extending upwardly from a lower portion of the enclosure to exhaust heat radiating from components housed therein to the exterior of the enclosure toward the top of the enclosure.

Abstract: To change image quality in accordance with the image to be displayed, a color filter plate 3 is driven to sequentially split the white light incident on an A portion into red, blue, and green light beams to irradiate a liquid crystal panel, thus displaying a full-color image by a so-called field sequential scheme. In this case, if a sector region 4BG of an auxiliary filter plate 4 is always matched to the A portion (FIG. 2A), the quality of a full-color image is defined by the color filter plate 3, resulting in an increase in luminance. In contrast to this, when a red filter section 3R and auxiliary red filter section 4R are synchronously driven to be simultaneously irradiated with white light, the quality of a full-color image is defined by both the color filter plate 3 and the auxiliary red filter section 4R. As a consequence, an image with excellent color reproducibility is obtained.

Abstract: An electro-optic display comprises a layer of reflective electro-optic material capable of changing its optical state on application of an electric field, an electrode, a heat generating component in heat conducting relationship with the electro-optic material, and a heat shield disposed between the heat generating component and the electro-optic material, the heat shield comprising a layer of thermally insulating material and a layer of thermally conducting material, the thermally conducting material being disposed between the thermally insulating material and the electro-optic material. The invention also provides an electrophoretic medium comprising a suspending fluid and a plurality of electrically charged particles suspended in the suspending fluid and capable of moving therethrough upon application of an electrical field to the electrophoretic medium, the suspending fluid containing a compatibilizer to reduce its coefficient of thermal expansion.

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 rotary optical filter apparatus containing an optical filter is integrated with a sirocco type cooling fan having a plurality of fan blades. The cooling fan is supported by a rotary holder of the optical filter apparatus so as to be integrally rotatable with the optical filter. The cooling fan inhales an air from its center part and discharges thus inhaled air from its outer peripheral part due to an action of the fan blades upon rotating, so as to make an airflow along the filter face and cool the optical filter.

Abstract: A cool-down system for portable projectors including a battery configured to power a cooling fan, if power to the cooling fan is cut off before the device has cooled down sufficiently to prevent degradation of one or more components.

Abstract: In an optical engine for a projection system, a fan unit is mounted on an upper surface of a housing, and has an inlet port facing toward light modulators within the housing for drawing air upwardly so as to dissipate heat generated by the light modulators, and an outlet port that is transverse to the inlet port for discharging the air drawn into the inlet port.

Abstract: A projection television set having an enclosure housing a screen, an optical unit and a mirror, wherein the optical unit and mirror are capable of projecting an image onto the screen. The enclosure is preferably constructed from hollow plastic extruded panels. In addition, the enclosure preferably includes a duct extending upwardly from a lower portion of the enclosure to exhaust heat radiating from components housed therein to the exterior of the enclosure toward the top of the enclosure.

Abstract: A projection television which can reduce noise generated in a cooling fan for cooling an internal high temperature heat. The projection television includes: a lamp for providing a light source; a circuit driving unit for supplying electric power; a cooling fan for cooling heat generated in the lamp and the circuit driving unit; a duct for inducing an air drawn in by the cooling fan and for externally discharging the air; and a resonator installed on the duct, for removing noise generated by the cooling fan. Accordingly, the projection television reduces the noise generated by the cooling fan, and removes the noise generated by other factors by adjusting a number of the resonators.

Abstract: Leak of refrigerant leak is prevented. Further, invasion of impurities into refrigerant liquid is prevented, and a stable projection image is obtained. The assembling steps are curtailed, and the projection television receiver is manufactured by a smaller number of assembling steps, and the cost is reduced. Moreover, a stable quality is maintained for a long period, and a high reliability is obtained. It includes a cathode-ray tube having a face surface, a projection lens disposed ahead of the face surface, a container disposed between the face surface and projection lens, a first sealing member disposed between the container and face surface, a second sealing member disposed between the container and projection lens, and liquid filling up the region enclosed by the container, face surface and projection lens. The container has a fluoride resin film disposed at least inside of the container, and the fluoride resin film contacts with the liquid.

Abstract: A cooling medium and a cooling device for optical equipment using the same, which cooling medium has a refractive index in a specific range, hardly causes the problem to dissolve or swell plastic lens and other component parts, and is flame retardant. The cooling medium comprises a cyclic aliphatic hydrocarbon having at least one cross linkage and has a flash point of 120° C. or above and a melting point of −20° C. or below. The space between a pair of transparent optical members of a cooling device for optical equipment, is filled with the cooling medium.

Abstract: A projection television set having a screen and three projection units each capable of projecting a monochromatic image onto the screen. The projection units each having a cathode ray tube (CRT) optically coupled to a projection lens, which includes both a C-lens and a compound lens. A spacer preferably having three optical passageways is coupled to and between the CRTs and projection lenses such that three coolant chambers are formed. Preferably, the spacer includes fluid passageways that interconnect the coolant chambers. Additionally, the packing members used to seal the coolant chambers preferably include position or alignment retaining components.

Abstract: Disclosed is a cooling structure for a projection television, which keeps the inside of the projection television clean and effectively cools the heated projection television. The cooling structure for the projection television comprises a heat blocking unit for separating a lamp system generating superheat from the sealed inner space, a cooling fan for forcibly cooling the heat generated by the synthesis system within the sealed inner space, the cooling fan being formed adjacent to the synthesis system, and a radiating unit for exhausting the heat of the inner space to the outside, the radiating unit being formed on the upper part of the housing.

Abstract: A CRT assembly of a projection TV system includes a CRT for forming an image, a projection lens for magnifying and projecting the image formed by the CRT, a coupler installed between the CRT and the projection lens, a coolant receiving portion formed at the center of the coupler, having a front surface in contact with the projection lens forming a seal and a rear surface in contact with a front surface of the CRT forming a seal, a coolant injection hole formed to penetrate the side of the coolant receiving portion, through which coolant is filled in the coolant receiving portion, and a pressure control device for controlling the pressure of coolant in the coolant receiving portion while sealing the coolant injection hole.

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: The invention provides a projector that is capable of efficiently cooling an outer case along with a light source device. The projector includes an outer case that accommodates a light source device and a cooling passage that is formed in the vicinity of the light source device to cool the outer case. Therefore, the inside of the outer case and the vicinity of the light source device are cooled by the cooling passage so as to cool the outer case efficiently. Also, since the cooling passage is arranged in the vicinity of the light source device, the light source device can also efficiently be cooled. As a result, a temperature rise in the light source device can be restrained so as to cool the outer case more efficiently.

Abstract: A projection display apparatus comprises a display device forming an image for projection to illuminate a display screen. A current source generates a current. A current sink is adjacent to the display screen and is coupled to the current source for receiving the current. A detector is coupled to the current source and the current sink for receiving the current and detecting a presence of the received current. Wherein a first condition, absent illumination by the projected image on the current sink, the current from the source divides and is coupled to the detector in accordance with a first ratio, the detector assuming a first state indicative of the absence of illumination, and in a second condition in accordance with an intensity of illumination by the projected image on the current sink, the current from the current source is received by the current sink in accordance with a second ratio and the detector, absent the received current, assumes a second state indicative of illumination on the current sink.

Abstract: A projection television set having a screen and three projection units each capable of projecting a monochromatic image onto the screen. The projection units each having a cathode ray tube (CRT) optically coupled to a projection lens, which includes both a C-lens and a compound lens. A spacer preferably having three optical passageways is coupled to and between the CRTs and projection lenses such that three coolant chambers are formed. Preferably, the spacer includes fluid passageways that interconnect the coolant chambers. The spacer also include coolant fill ports and reservoirs, zero pressure gum tanks seated in the reservoirs, and a plurality of heat exchanging ribs.

Abstract: A projector, which projects color images using the three liquid crystal panels (41-43) while cooling them by the fans (611-613) for G, R, and B panels, comprises the level calculation unit (711) for finding the intensity levels of the R, G, and B components of image signals, the level calculation unit (721) for finding the voice levels of voice signals, the fan control unit (73) for controlling the numbers of revolutions of the fans (611-613), and the memory (761) for storing the cumulative amount of lighting time of the lamp (21). As the intensity levels get higher, the numbers of revolutions of the fans are increased, and as the cumulative amount of lighting time becomes larger, the numbers of revolutions of the fans are decreased. As a result, unnecessary noises caused by the fans (611-613) can be reduced while the liquid crystal panels (41-43) are properly cooled.

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: An air-cooling apparatus for a projection television is disclosed. The projection television includes a front casing forming an external appearance of a body of the projection television and having a screen installed therein. A rear casing is coupled to the front casing and has a reflection mirror installed therein. A base is integrally formed at a lower portion of the front casing and has an opening and defines a space below the opening. A blowing duct is installed above the opening in the base, and an image projector is installed above the blowing duct and has heat emitting elements including a beam source, dichroic mirrors, a liquid crystal panel and a projection lens therein. A distributing member is disposed within the space and cooperates with the blowing duct so as to distribute air blown by the blowing duct to the heat emitting elements.

Abstract: An analog delay circuit which includes an analog memory circuit wherein a plurality of memory cells each including a memory capacitor and a selection switch for the memory capacitor are arranged in a matrix includes row switches provided for the individual columns for individually being driven by row selection signals. A same clock signal from a clock generation circuit is supplied commonly to an X direction scanning circuit and a Y direction scanning circuit. The number of stages of registers of the X direction scanning circuit and the number of stages of registers of the Y direction scanning circuit are set so that they have no common divisor other than 1. Consequently, when the memory cells are to be selectively scanned, a same selection condition can be provided to all of the memory cells without relying upon the positions of the memory cells, and the parasitic capacitance connected to a signal write/read terminal is reduced.

Abstract: In a projecting unit of a projector, a projecting tube is sealingly attached to a projecting tube frame by means of a packing member, a projecting lens is sealingly attached to a projecting lens frame by means of a packing member, and an image on the projecting tube is projected on a screen by the projecting lens. A packing member is interposed between and in engagement with the frames such that the frames are sealingly attached, and can slide against said packing member. The frames are secured to each other for use of the projecting unit, or separated from each other to permit adjustment of the space between the frames.

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.