Abstract: A projection type image display apparatus includes an image display element, a first lens group disposed in a light direction with respect to the image display element and configured to include a plurality of lenses, a second lens group disposed in a light direction with respect to the first lens group and configured to include a plurality of lenses, a reflection mirror, configured to reflect lights emitted from the first and/or second lens groups so as to project upon the screen obliquely, a first mounting base on which the first lens group is mounted, a second mounting base on which the second lens group is mounted, and a chassis configured to store the first and second lens groups, the reflection mirror, and the first and second mounting bases. The first mounting base is fixed at a bottom of the chassis, while the second mounting base is moveable.

Abstract: There is provided a projection apparatus using an oblique projection optical system, which generates little reflection loss by providing a linear Fresnel lens at an incident surface in the case where the apparatus is used as a linear system, wherein said linear Fresnel lens makes total reflection of image light, and is capable of obtaining total surface property with good brightness in a region with small incident angle onto a screen, by using a total reflection Fresnel lens and a refraction Fresnel lens in combination. In addition, total surface property with further good brightness can be obtained by using a plurality of projection image display apparatuses in the same projection apparatus.

Abstract: A projection-type image display apparatus for projecting an image, enlargedly, onto a projection surface, comprises: an image display element; a lens group, being disposed behind the image display element, comprising therein, a front lens group made up with a plural number of lenses, including, at least, a refractive lens, and a rear lens group made up with a plural number of lenses, including, at least, a lens having a free curved surface configuration and being rotationally asymmetric, thereby emitting an image displayed on the image display element; a reflection mirror for reflecting the light from the lens group, thereby projection onto the projection surface, obliquely; and a movement member for moving the plural number of lenses of the rear lens group.

Abstract: A projection optical unit for a projection display apparatus, which displays an image upon a projection surface, obliquely, includes a front lens group disposed in a direction from an image display element to a projection surface, a rear lens group, and a reflection mirror formed so that a curvature of a portion for reflecting a light beam incident upon a lower end portion of the projection surface is larger than a curvature of a portion for reflecting a light beam incident upon an upper end of the projection surface. An optical axis of the front lens group and the rear lens group is more inclined with respect to a direction of the portion of the reflection mirror for reflecting the light beam incident upon the lower end portion of the projection surface than a normal line direction of the image display element.

Abstract: A projection type image display apparatus includes an image display element, and a projection optical unit, which is configured to project an image displayed on the image display element, enlargedly, upon a screen. The projection optical unit includes a lens group, which is configured to compensate an distortion on an image surface on the screen, a mirror for compensating a trapezoidal distortion on the screen. The mirror reflects lights emitted from the lens group, so as to project upon the screen obliquely.

Abstract: A projection type image display apparatus includes a lens group, being disposed adjacent to an image display element, which is configured to include a plural number of lenses, and a mirror, which is configured to reflect emission lights from the lens group, so as to project upon the screen obliquely. A ratio (Lo/Lp) between a distance (Lp) from a center of the mirror up to the screen and a diagonal size (Lo) of the screen is at least 2.

Abstract: A projection type image display apparatus includes an image display element, a first lens group disposed in a light direction with respect to the image display element and configured to include a plurality of lenses, a second lens group disposed in a light direction with respect to the first lens group and configured to include a plurality of lenses, a reflection mirror, configured to reflect lights emitted from the first and/or second lens groups so as to project upon the screen obliquely, a first mounting base on which the first lens group is mounted, a second mounting base on which the second lens group is mounted, and a chassis configured to store the first and second lens groups, the reflection mirror, and the first and second mounting bases. The first mounting base is fixed at a bottom of the chassis, while the second mounting base is moveable.

Abstract: In a projection type video display apparatus, in order to assure sufficient brightness by suppressing a decrease in light utilization efficiency inside a limited output aperture area of a light source unit, a transmission or reflection type liquid crystal is used for a video display device and the light source unit having a plurality of reflectors or focusing mirrors in correspondence with LED's representing light sources is so constructed as to satisfy D<4×f or D<4×Z, where D represents an effective diameter of a reflector, f represents a focal distance of a mirror and Z represents a distance between a light emitter of the light source and an apex at a center of the mirror.

Abstract: A projection optical unit for obliquely projecting an image displayed on an image display element upon a projection surface, enlargedly, comprises: a lens group, being disposed neighboring to the image display element, and including a plural number of projection lenses therein; and a reflection mirror for reflecting lights emitting from the lens group, to be projected onto the projection surface, obliquely, wherein assuming that a light beam, emitting from a center of the display screen of the image display element, passing through a center of an entrance pupil of the lens group, and entering into a screen center on the projection surface, is a screen center light beam, then the screen center light beam is incident upon the projection surface, obliquely, with respect to a normal line thereon, the lens group comprises a front lens group including a plural number of refraction lenses, being disposed thereafter directing from the image display element to the projection surface and having rotationally symmetric s

Abstract: A projection-type image display apparatus for projecting an image, enlargedly, onto a projection surface, comprises: an image display element; a lens group, being disposed behind the image display element, comprising therein, a front lens group made up with a plural number of lenses, including, at least, a refractive lens, having a positive power and being rotationally symmetric in a surface configuration thereof, and a rear lens group made up with a plural number of lenses, including, at least, a lens having a free curved surface configuration and being rotationally asymmetric, thereby emitting the image displayed on the image display element; a reflection mirror for reflecting the light from the lens group, thereby projection onto the projection surface, obliquely; a first mounting base, on which the rear lens group is mounted; and a rod member, which is provided on the mounting base for moving the mounting base.

Abstract: A projection-type image display apparatus for projecting an image, enlargedly, onto a projection surface, comprises: an image display element; a lens group, being disposed behind the image display element, comprising therein, a front lens group made up with a plural number of lenses, including, at least, a refractive lens, having a positive power and being rotationally symmetric in a surface configuration thereof, and a rear lens group made up with a plural number of lenses, including, at least, a lens having a free curved surface configuration and being rotationally asymmetric, thereby emitting the image displayed on the image display element; a reflection mirror for reflecting the light from the lens group, thereby projection onto the projection surface, obliquely; and a movement member for moving the plural number of lenses of the rear lens group.

Abstract: A projection type display apparatus including an oblique projection optical system having a plurality of lenses is disclosed. A lens nearest to a projection screen has a vertical effective image area through which a light flux passes. The lens is arranged at a position not including an optical axis shared by the largest number of lenses among the plurality of lenses. A flat mirror for returning the optical path is arranged between the particular lens and the projection screen at a predetermined angle to the optical axis. An enlarged image obtained by the light flux returned by the flat mirror is formed toward a display screen.

Abstract: A projection-type image display apparatus includes an image display element, a light source unit, an enlarging projection optical unit, and a display controller portion. The enlarging projection optical unit, includes a projection lens, a group of lenses which are disposed on a same optical axis, sequentially arranged from a side of the image display element and which include at least one lens having a lens surface, and a reflection mirror having a reflection surface which is disposed between the group of lenses and a display portion. The image display element has a display surface larger than a display surface of the display portion, when an entirety of the image display element is enlargedly projected on the display portion through the enlarging projection optical unit; and the display controller portion enables movement of the image on the display surface of the image display element.

Abstract: The light diffusion component in accordance with the present invention includes light transmission pieces that are juxtaposed at predetermined intervals in one direction and have a substantially trapezoidal section, and a light absorption piece that is juxtaposed alternately to the light transmission pieces and has a substantially wedged section. The upper base of the substantially trapezoidal section of each light transmission piece adjoins the base of the substantially wedged section of the light absorption piece. The area of the substantially wedged section of the light absorption piece is equal to or larger than one-third of the area of a trapezoid bordering the substantially wedged section, and equal to or smaller than two-thirds thereof.

Abstract: A projection-type display apparatus, comprises a front lens group having a plural number of lenses, each having rotationally symmetric surface configuration, a rear lens group, being disposed in rear of the front lens group, including a refractive lens for diverting a light and having a rotationally symmetric surface configuration, and a plural number of free curved surface lenses, each having a rotationally asymmetric free curved surface configuration, and a reflection mirror, being disposed in rear of the rear lens group, having a convex configuration into a direction of reflection of light and a rotationally asymmetric free curved surface configuration, at least in a part thereof.

Abstract: In a projection-type image display apparatus, comprising an enlarged projection optical unit, which is configured to project the lights from the light source unit onto the display portion, enlargedly, the enlarged projection optical unit, further comprises: a projection lens for projecting the image on the image display element, enlargedly, and a reflection mirror having a reflection surface made up with a freely curved surface, and the image display element has a display surface larger than the display portion, when a whole body thereof is projected on the display portion, through the enlarged projection optical unit, to be displayed by projection thereof, and the image on the display surface of the image display element is movable, within the display surface of the image display element, so as to project a portion fitting to the display portion, selectively, to be displayed, when projecting it through the enlarged projection optical unit upon the display portion, to be displayed, thereby enabling an install

Abstract: A projection type video display apparatus having improved color separating ability is provided. The projection type video display apparatus includes a color separating unit including an entrance plate provided with an aperture through which light beams emitted by a light source travel, an optical integrator, and a plurality of dichroic mirrors disposed with their color separating surfaces extended substantially parallel to the exit surface of the optical integrator and capable of transmitting color light beams of wavelengths in a predetermined wavelength range and of reflecting color light beams of wavelengths outside the predetermined wavelength range.

Abstract: In a projection type image display apparatus, for enlarging an image on a image display apparatus 1 by means of a projection lens 2, thereby projecting the enlarged image onto a screen 6, obliquely, being inclined thereto, between the projection lens 2 and a rear-surface mirror 5, there are disposed free shaped surface mirrors 3 and 4, each having a free shaped surface for compensating a trapezoidal distortion due to oblique projection of the enlarged image. The surface configuration of the free shaped surface mirror is so shaped as to satisfy a following equation: |L1?L2|>1.4·Dv if assuming that a distance for a light beam of an upper end of the enlarged image to reach the screen after being reflected upon a free shaped surface is “L1”, a distance for a light beam of a lower end of the enlarged image to reach the screen after being reflected upon the free shaped surface is “L2”, and a distance from an upper end of an image on the screen to a lower end thereof is “Dv”.

Abstract: In a projection-type image display apparatus, comprising an enlarged projection optical unit, which is configured to project the lights from the light source unit onto the display portion, enlargedly, the enlarged projection optical unit, further comprises: a projection lens for projecting the image on the image display element, enlargedly, and a reflection mirror having a reflection surface made up with a freely curved surface, and the image display element has a display surface larger than the display portion, when a whole body thereof is projected on the display portion, through the enlarged projection optical unit, to be displayed by projection thereof, and the image on the display surface of the image display element is movable, within the display surface of the image display element, so as to project a portion fitting to the display portion, selectively, to be displayed, when projecting it through the enlarged projection optical unit upon the display portion, to be displayed, thereby enabling an install

Abstract: A projection type image display apparatus is provided which includes a housing to hold an optical system including multi-lenses, a polarized-light conversion element and the color separation portion The housing operates to provide an optical path between a light source, located outside the housing, and penetration-type image display elements and an optical synthesizing portion also located outside of the housing.