Abstract: In a liquid crystal projection color display apparatus having three liquid crystal display devices used for red, green and blue light, each liquid crystal display device has a liquid crystal display panel and a microlens array disposed on the light-source side or the light-source and screen sides of the liquid crystal display panel. The microlens array has a controllable refractive power which is controlled by applying an electrtical power thereto. An electrical voltage is applied between transparent electrodes formed on both surfaces of a microlens array so that the refractive power of the microlens array can be made a value adapted to suit the corresponding one of red, green and blue light.

Abstract: A projection type image display apparatus uses an optical modulation image display device as a light valve. Notwithstanding the use of a metal vapor discharge lamp which has a long re-starting period of time as a light source, the apparatus can display images instantaneously by igniting the discharge lamp for a prescribed period of time after switching off and then on again a main power source of the apparatus. Also, the projection type image display apparatus does not generate audio noise at the time of starting the discharge lamp. Furthermore, even in case of adding an instantaneous re-ignition circuit, the frequency of use of such instantaneous re-ignition circuit can be suppressed to an utmost extent, and the useless igniting period of time of the discharge lamp can be curtailed.

Abstract: In a liquid crystal projection display apparatus, light is emitted from a light source and is separated and directed to pixels of a liquid crystal display element and condensed at the center of each pixel with a first microlens array. The light which has passed through the liquid crystal display element is converted into approximately parallel rays with a second microlens array. The light which has passed through the second microlens array is projected onto a screen via a projection lens.

Abstract: A projection type liquid crystal color display apparatus has three liquid crystal display panels which are the same in structure. Two of the three liquid crystal display panels are controlled so that signal lines are scanned from right to left and scanning lines are scanned from top to bottom. The third liquid crystal display panel is controlled so that signal lines are scanned from right to left and scanning lines are scanned from bottom to top. Each of the three liquid crystal display panels may be connected at the same side thereof to a flexible board provided for the supply of an input signal to a driver IC for driving the liquid crystal display panel.

Abstract: A liquid crystal image projection system projects an enlargement of an image formed in an active matrix liquid crystal panel onto a screen by using a lamp and a projector lens. The orientation of the liquid crystal panel is made such that a molecular axis vector directed from an input light side end to an output light side end of each liquid crystal molecule in the middle of the liquid crystal layer has a vector component opposite to the scanning direction of the panel, and a convergent light is entered into the liquid crystal panel. The system can solve the problem of nonuniformity of the signal voltage-transmittance characteristic of the entire screen.

Abstract: A projection lens enlarges and projects optical images in a matrix type light valve onto a screen. The projection lens includes a front lens group of the retrofocusing type; a rear lens with aspherical surfaces whose radii of curvature in the peripheral portion are shorter than that in the central portion; and a reflecting mirror which is positioned between the front lens group and the rear lens and diverts the optical axis. This projection lens enables the optical images in the light valve to be projected with a high contrast and a wide field angle. A projection system is provided which includes a light source; a light valve; a converging optical apparatus; a transmission type screen; diverting place mirrors; and a projection lens to enlarge and project the optical images in the light valve onto the screen. Since the projection lens has a wide field angle and has the reflecting mirror provided therein, the projection system can be very compact.

Abstract: A projection display apparatus has a light source, a component color separator, a light transmitter(s), three light valves, a light combiner, a single projection lens, and a drive circuit. The light transmitter includes an input side convergent lens for producing a real image of a luminous element in the light source at a location adjacent to a central convergent lens. The central convergent lens produces a real image of an object situated about a position of the input side convergent lens at a location adjacent to an output side convergent lens. The output side convergent lens permits its output light to reach the projection lens. Accordingly, divergent light is converged along a considerably extending portion of the optical path and directed to the projection lens so that the efficiency of light in use can be improved, thus allowing the projection display apparatus to remain compact in size and provide a great light output power.

Abstract: A video projector utilizes a reflective liquid crystal light valve of the active matrix system and a polarizing beam splitter. An active matrix array circuit of the light valve has pixel electrodes arranged in a matrix mattern. The pixel electrodes each has a reflective surface for reflecting a light beam and protects corresponding switch elements from the light beam. There are provided at least two switch elements for each of the pixel electrodes so as to enhance the redundancy of the array circuit. Further, each pixel electrode is provided with a suitable additional capacitance.

Abstract: A projection display apparatus which is designed to separate a light from the light source into color lights of three primary colors by a color separator, irradiate the respective color lights to corresponding three light valves, combine the optical images on the light valves by a light combiner formed by intersecting dichroic reflection surfaces in X-letter form, followed by projecting the combined image by enlargement on a screen with a projection lens. The color separator is made by intersecting in X-letter form a first and second flat plate type dichroic mirrors. The second dichroic mirror is composed of two small dichroic mirrors made by separating into two parts of the intersecting part. The two small type dichroic mirrors are disposed on mutually different places so that, when viewed from the output side of the light which advances straightly through the color separator, the two edge surfaces which form the intersecting part of the two small dichroic mirrors are seen as being in overlapped state.

Abstract: The invention relates to a liquid crystal display device and a projection TV using same. The liquid crystal display device has microfine conductive bumps formed on terminals of a liquid crystal display panel, and a conductive joint layer formed on each conductive bump. The display panel is connected to wiring leads formed on a substrate provided thereon an IC drive circuit. The projection TV employs a liquid crystal display device in which three liquid crystal display panels corresponding to three colors, red, green, and blue, are mounted on a single substrate. Light beams are made incident on the respective panels, and light beams transmitted through or reflected from specified pixels are projected on a screen to form an image.

Abstract: An optical system for projection television apparatus has three projection cathode-ray tubes for producing red, green and blue monochrome images, respectively. Three projection lens systems are disposed in front of faceplates of the projection cathode-ray tubes, respectively for producing the red, green and blue screen, each of the projection lens systems having a rear lens element having a negative power and disposed in front of a corresponding one of the cathode-ray tubes and a front group having a positive power and disposed in front of the rear lens element, the rear lens element having a concave surface facing the front group. In each of at least two of the three projection lens systems, the optical axis of the front group is tilted to that of the rear lens element, and the optical axis of the rear lens element is in parallel with or aligned with that of the corresponding one of the projection cathode-ray tubes.

Abstract: A projection lens having a large aperture ratio has 3 units for projecting an enlargemen of an image appearing on a CRT onto a screen. The first unit from the screen has a negative power so that the entrance pupil is moved toward the screen to thereby improve off-axis vignetting factor. The second unit consists of two positive power lens elements so that the positive power of the entire system is shared by the second unit and the temperature characteristic is improved by using a positive power glass lens element as one of the two positive power lens elements. The third unit has a negative power to correct curvature of field.

Abstract: A compact projection lens for projecting an enlargement of an image appearing on a cathode ray tube (CRT) onto the screen. The projection lens has a first lens having a positive optical power and at least one aspheric surface, surface of the first lens that faces the screen being convex, a second lens having bi-convex surfaces and a positive optical power, and a third lens having a negative optical power and an aspheric concave surface facing the second lens. The focal length f.sub.1 of the first lens and the focal length f.sub.2 of the second lens are selected for satisfying a condition of0.55<f.sub.1 /f.sub.2 <1.2.

Abstract: A liquid-cooled projection tube apparatus has a projection tube, a metal plate having an opening and fixed in close contact with a face plate of the projection tube, and a transparent plate made of resin fixed in close contact with the metal plate. A space surrounded by the face plate, metal plate and transparent plate is filled with a liquid. The transparent plate has a groove, and the metal plate has a projection around the opening which is fitted into the groove so that the transparent plate is easily positioned with respect to the metal plate and that the liquid is sealed within the space.

Abstract: A projection lens system for a projection television for projecting on a screen an enlargement of an image displayed on a cathode ray tube includes a first bi-aspherical lens of positive power, the surface of which is toward the end of the lens system which is to face the screen being a convex surface having a larger curvature than the other surface thereof, a second double convex lens of glass, and a third bi-aspherical lens of negative power, the surface of which is toward the screen end being a concave surface having a larger curvature than the other surface thereof, the first, second and third lens being disposed in the order from the screen end, and satisfying the conditions: 1.3f<f.sub.1 <1.9f; 0.9f<f.sub.2 <1.2f; 0.25f<d.sub.4 <0.35f; r.sub.1 <.vertline.r.sub.2 .vertline.; and 0.4<r.sub.3 /.vertline.r.sub.4 .vertline.<0.75, where f is the total focal length, f.sub.1 and f.sub.2 are the respective focal lengths of the first and second lenses, d.sub.

Abstract: A projection television apparatus having three monochromatic cathode-ray tubes, a mirror block and a lens. The three cathode-ray tubes which display red, green and blue images, respectively are placed to form the letter "T" with their faceplates facing each other. The mirror block consists of two dichroic mirrors intersecting to form the letter "X". Red, green and blue images from the three cathode-ray tubes are combined into one color image by the mirror block, and the resulting color image is enlarged and projected on the screen by a single lens. It is possible for the mirror block to be moved linearly in one direction without rotation. The focus adjustment of the projected image on the screen may be carried out by moving both the mirror block and the lens without moving the cathode-ray tubes.

Abstract: A projection television apparatus having a retrofocus type projection lens system which has a sufficiently long back focus, a small F number and a large distortion. The lens system is constructed with five components and five lenses and comprises a first lens which is a negative meniscus lens that has at its screen side a convex surface, a second lens which is a biconvex lens, a third lens which is a biconcave lens, a fourth lens which is a positive lens, and a fifth lens which is a biconvex lens, and which is defined by the following four conditions, i.e.1.4f<.vertline.f.sub.1 .vertline.<1.9f (i)0.35f<d.sub.2 <0.55f (ii)0.8f<r.sub.3 <1.2f (iii)0.15f<d.sub.4 <0.35f (iv)where f is the composite focal length of the total lens system, f.sub.1 is the focal length of the first lens, d.sub.2 is the air space between the first lens and the second lens, d.sub.4 is the air space between the second lens and the third lens, and r.sub.

Abstract: A projection television apparatus which has three monochromatic cathode-ray tubes, two type of dichroic mirrors, and a lens. Red, green and blue images from the three tubes are combined into the color image by the two types of dichroic mirrors and the resulting image is enlarged and projected on the screen by one lens. The two types of dichroic mirrors are crossed at a right angle in the shape of an "X". Each type of dichroic mirror is split in two through the line of intersection and the two parts of the respective dichroic mirrors of each type have different transmission characteristics, so that color shading is improved.