Abstract: A once-through forced air-cooled heat sink according to the present invention comprises: a heat sink portion which is configured to be attached to an object that is to be cooled; and a blower for introducing cooling air into the heat sink portion. The heat sink portion comprises: an air inlet; an air outlet; and fins for dissipating heat in the object with the aid of cooling air which is supplied by the blower. The air inlet, the air outlet, and the fins are arranged such that the cooling air is introduced from the air inlet, then cools the fins and flows to the air outlet in a once-through pattern.

Abstract: A projector apparatus has a projection device for projecting an image onto a projection surface; at least two displacement sensors for detecting horizontal displacements of the projector apparatus, the displacement sensors being spaced a predetermined distance from each other; a rotational angle calculator for calculating a rotational angle of the projector apparatus in a horizontal plane using the predetermined distance and the horizontal displacements, the horizontal displacements being detected by the displacement sensors; and a distortion corrector for correcting distortion of the image by using the rotational angle, the image being projected by the projection device, wherein the rotational angle is calculated by the rotational angle calculator as a horizontal corrective angle.

Abstract: A spatial light modulating-type video display device is provided which has excellent color reproductivity of a video even when a light source is used which emits light having chromaticity coordinates of each of three primary colors (R, G, and B) being different from those designated by specifications of colorimetry.

Abstract: A transportable projector includes a focus adjustment unit for moving a focus lens in a projection lens, an acceleration sensor for detecting acceleration in a direction along an optical axis of the projection lens in the projector, a determination unit for determining whether the projector is in a stationary state or in a moving state in accordance with an output of the acceleration sensor and for respectively determining the direction to which the projector has moved and the distance that the projector has moved in accordance with an output of the acceleration sensor, and a control unit for controlling movement of the focus lens by the focus adjustment unit in accordance with the determined direction and the determined distance of the projector.

Abstract: An optical unit has a first lens holder holding a first lens and a second lens holder holding a second lens, the first lens holder and the second lens holder being mounted on a common lens base. The first lens holder is movable in the direction of one side of the exit end face of a light tunnel, and the second lens holder is movable in the direction of another side, adjacent to the one side, of the exit end face of a light tunnel. The first lens holder and the second lens holder are independently moved to bring an illuminating light area on a DMD, as an image forming device, into alignment with an image forming area on the DMD. The illuminating light area can thus be accurately positioned in the image forming area on the DMD. The optical unit has a high light utilization efficiency and can easily be operated for positional adjustment of the illuminating light area. The optical unit is incorporated in a projection display apparatus.

Abstract: A projector has an image generating device for generating an image, and a housing, having the image generating device disposed therein and having an opening defined therein for emitting therethrough projection light representing the image from the image generating device. A projection mirror is mounted on an outer surface of the housing for reflecting the projection light to project the image onto a projection surface. An optical system is disposed in the opening for applying the projection light to the projection mirror. The projector also has a foreign matter detector for detecting foreign matter which enters a light path of the projection light between the optical system and the projection mirror.

Abstract: An auxiliary line created on a computer is displayed on a user interface screen, and is projected onto a curved screen by a projector. The user adjusts real numbers substituted into variables of an approximate expression held in the computer for drawing auxiliary line to transform the auxiliary line drawn on the user interface screen for a correction such that the auxiliary line in the image projected from the projector through a video cable approaches to a straight line. If this correction causes the auxiliary line to extend beyond the screen of a display, the computer scales down the current user interface screen, and creates a virtual correction area therearound, so that the auxiliary line can be fully displayed within the screen.

Abstract: A luminous flux, from one conjugate surface (A), having an opening angle of at least 10° sequentially passes through a first optical system (30) having a luminous flux convergent action in the vicinity of its reference axis and a second optical system (31) having a luminous flux divergent action in the vicinity of its reference axis, and converges on another conjugate surface (B). A specific condition is given to the converging distance of each converging point at a luminous flux section including a principal ray according to the v passing position of the luminous flux through the first optical system (30) to thereby implement an oblique-incident optical system having a half angle of at least 60° and a comparatively simple structure irrespective of a type of an optical element used.

Abstract: In lamp unit 10 having light source lamp 1, reflector 2 for reflecting light from light source lamp 1, reflector holding member 11, and reflector cover 15, a plurality of cooling holes 18a are formed in a region of reflector holding member 11 provided with lamp unit positioner 16a. Cooling holes 18a are open toward an upper bulb area, a lower bulb area, and a cathode of the light source lamp, respectively. Stud 22a for fixing reflector holding member 11 has a throughhole extending at the center thereof, so that cooling air fed from high static pressure blower 27 can be sent to cooling holes 18 through tube 28 and the throughhole of stud 22a, thus efficiently cooling the upper bulb area, lower bulb area, and cathode of light source lamp 1 in a concentrative manner with a small amount of air. Thus, the resulting lamp unit, provided by the present invention, can reduce the amount of air required for cooling the lamp, and can use a high static pressure and small fan.

Abstract: A projection display apparatus has a light source, an image forming device for modulating light emitted from the light source with an image signal supplied thereto, and a reflective optical system for magnifying and projecting an image generated by the image forming device. The reflective optical system has a first reflecting mirror for reflecting light emitted from the image forming device and initially applied thereto, and a plurality of reflecting mirrors for successively reflecting the light reflected by the first reflecting mirror. The first reflecting mirror has a spherical reflecting surface, and a normal line passing through the crest of the spherical reflecting surface and a normal line passing through the image forming device extend nonparallel to each other.

Abstract: A flicker detection system according to the present invention has an AC component extracting circuit that extracts an AC signal from a voltage applied to a lamp, the AC signal being an AC component of the voltage applied to the lamp, a display section adapted for displaying the information that flicker has occurred, and a control section that has a reference voltage registered in advance for determining that flicker has occurred and instructs the display section to display the information that flicker has occurred in the lamp, depending on the result of comparison between the reference voltage and the AC signal received from the AC component extracting circuit.

Abstract: A projection display apparatus comprises a liquid crystal unit assembly which includes a liquid crystal panel, an incident side polarizing plate and an emitting side polarizing plate which are arranged on an incident side and on an emitting side of the liquid crystal panel, respectively, and a color combining prism. The apparatus further comprises a fan; a duct which is connected to the fan and which is provided with an opening for supplying cooling air, wherein the opening is arranged near the liquid crystal panel and the incident side polarizing plate; a holder for holding the emitting side polarizing plate and the color combining prism; and a heat exchanger which is connected to the holder, wherein the heat exchanger uses liquid coolant.

Abstract: An image transmitting method is disclosed for reducing the load on a CPU of an image transmission apparatus. An image change monitoring unit provided in the image transmission apparatus monitors the latest image used to generate image data transmitted to an image reception apparatus via a network, and a subsequent image to determine whether or not the latest image has changed. An image capture unit captures the image after the image has changed to acquire the image when the image change monitoring unit determines that the latest image has changed.

Abstract: There is provided a projector apparatus having an image forming optical system including a plate fixed to a housing, and a plurality of reflecting mirrors attached to the plate through respective holding members. The material of the reflecting mirrors, and the materials of the plate and the holding members have approximately equal coefficients of linear expansion. Sliding means is provided at a contact point between the housing and the plate for releasing an excessive force generated at the contact point.

Abstract: A computer calculates the shape of a figure after transformation using an approximate expression previously set for correcting a projected image for distortion associated with the shape of a projection surface of a cylindrical screen (an equation representative of a parabola in this case), a variable for horizontal transformation and a variable for vertical transformation which are entered through a user interface for transforming the approximate expression, and/or a variety of parameters required for transformation of image and optical corrections such as the optical center, linearity, amplitude, and position. A projector scales up or down pixels to produce a transformed image from the calculated figure after transformation for projection onto the cylindrical screen.

Abstract: A picture quality improvement device has two-dimensional low-pass filter that takes as input a luminance signal YIN that is obtained from a video signal and that extracts low-pass components for a vertical direction and a horizontal direction of the input luminance signal YIN. The picture quality improvement device adds an edge signal, which is obtained by subtracting from luminance signal YIN the low-pass extraction signal (LPF) that has been extracted by two-dimensional low-pass filter, to luminance signal YIN. Two-dimensional low-pass filter is constituted such that the extraction gain of the vertical direction low-pass component and the extraction gain of the horizontal direction low-pass component are independently adjusted.

Abstract: An ultrasonic receiver receives an ultrasonic signal having a period in which an amplitude thereof progressively increases as time elapses. A pattern matching unit determines whether a comparative pattern, which is generated as a result of comparison between the respective maximum amplitude values of a plurality of successive waves of said wave signal and a threshold value set by a threshold setting unit, matches a reference pattern or not during the period of the ultrasonic signal. The pattern matching unit determines that the ultrasonic receiver has successfully received the ultrasonic signal if the comparative pattern matches the reference pattern.

Abstract: A projector has an image generating device for generating an image, and a housing, having the image generating device disposed therein and having an opening defined therein for emitting therethrough projection light representing the image from the image generating device. A projection mirror is mounted on an outer surface of the housing for reflecting the projection light to project the image onto a projection surface. An optical system is disposed in the opening for applying the projection light to the projection mirror. The projector also has a foreign matter detector for detecting foreign matter which enters a light path of the projection light between the optical system and the projection mirror.

Abstract: A projector has a transmission time information reception unit for calculating the distances between a transmitter and first and second ultrasonic receivers based on reception times of ultrasonic and infrared pulses transmitted from a transmitter-equipped pointer rod for pointing to positions on a projection surface. The projector also has an image correcting information calculation unit, which, when a test pattern made up of a plurality of reference points including a plurality of points near the corners of the upper and lower edges of the projection surface is projected onto the projection surface, generates a coordinate transformation table to bring the coordinates of the reference points near the upper edge into conformity with the coordinates of corresponding desired corrective points, from the distance information acquired by the transmission time information reception unit through the transmitter-equipped pointer rod and positional information of the desired corrective points.

Abstract: An optical system for a display panel is disclosed. An optical system comprises a color separating portion for separating light that is emitted from a light source into a plurality of beams having different spectra; and a projecting portion for projecting the plurality of beams onto a plurality of divided areas of a predetermined range in the display panel, while sequentially switching the plurality of beams.