Abstract: A holographic element is a reflective holographic element formed on a substrate and constituted by a composite hologram having a plurality of patterns of interference fringes composed of interference fringes nonparallel to the substrate. The holographic element forms, out of image light having a predetermined wavelength width emanating from an image display element, a plurality of observation pupils at spatially different locations, and acts in such a way as to fulfill prescribed conditions for an identical incident ray over the entire area in which the image light is incident on the holographic element.

Abstract: A holographic element is a reflective holographic element formed on a substrate and constituted by a composite hologram having a plurality of patterns of interference fringes composed of interference fringes nonparallel to the substrate. The holographic element forms, out of image light having a predetermined wavelength width emanating from an image display element, a plurality of observation pupils at spatially different locations, and acts in such a way as to fulfill prescribed conditions for an identical incident ray over the entire area in which the image light is incident on the holographic element.

Abstract: A display apparatus which has a mirror with a free curved reflective surface of which curvature fluctuates with inflection points, a liquid crystal display (LCD), a back light and a polarizer. Light of an image which was modulated by the LCD is reflected by the free curved reflective surface and passes through the polarizer. Then, the light is directed to an optical pupil. Since the curvature of the free curved reflective surface fluctuates with inflection points, curvature of field and distortion can be corrected properly, and an image of high quality can be formed.

Abstract: An image display apparatus has a signal input portion for receiving an image signal, an image compensator for electrically compensating the image signal for distortion so that a left and a right image displayed in an observer's left and right eyes have identical distortion and then outputting a left and right image signal that correspond to the left and right images, a signal switcher for switching between the left and right image signals output from the image compensator so as to output the left and right images alternately chronologically, a single two-dimensional image display device for displaying a two-dimensional image in accordance with the image signal output from the signal switcher, a pair of left and right eyepiece optical systems for directing image light exiting from the two-dimensional image display device to the observer's left and right eyes so that the two-dimensional image is displayed as a virtual image in the observer's eyes, and an optical path switcher for time-divisionall

Abstract: A display device has a plurality of light emitting elements for emitting lights, a display element for modulating the light emitting from the plurality of light emitting elements so as to convert it to an image light showing an optical image, a reflection type hologram element, having a positive optical power with respect to the lights from the plural light emitting elements, for diffracting and reflecting the lights from the plural light emitting elements to approximately one direction so as to guide the diffracted and reflected lights to the display element; and an enlarging optical system for forming an enlarged image of the optical image converted by the lights from the image display element. The plural light emitting elements are positioned in a plane approximately vertical to an optical path of the lights diffracted and reflected by the hologram element.

Abstract: A viewing optical system of an optical apparatus has an objective system for forming an image of an object and an eyepiece system for enlarging and directing the image to the pupil. The viewing optical system also has a hologram combiner comprising holograms of the volume type, phase type, and reflective type and having optical power for constructing a surface which is optically equivalent to the image surface at a different position than the image when viewed from the pupil. The system also includes an information display means for displaying information at the position of the equivalent surface, wherein the hologram combiner transmits light from the image and reflects light from the information display means so as to allow viewing of an image together with the information display overlaid onto the image.

Abstract: A compact, high resolution projection imaged display device using a reflective-type display element which uniformly illuminates the entirety of the display element without reducing illumination efficiency and ensures viewing conditions of excellent and uniform brightness extending to the fringe of the field of view is provided by an illumination optical system for redirecting illumination light from an illumination light source onto a reflective-type display element. The reflective-type display element reflects light into the viewing optical system wherein the illumination optical system is constructed so as to have an approximate conjugate relationship between the pupil of the user and the illumination light from the illumination light source.

Abstract: An image display device for displaying a combined image by combining an virtual image with an external object, has a reflective type hologram combiner having an optical power for forming a surface optically equivalent to the external object at a position different from the external object, an image display for displaying an image to be provided as the virtual image at the position of the surface formed by the optical power of the combiner, and a selection surface for selectively reflecting and transmitting an image light from the image display and an external light from the external object. In the image display device, the image light is reflected by the selection surface, reflected by the hologram combiner, transmitted through the selection surface, and thereafter directed to the pupil of an observer, while an external light is transmitted through the hologram combiner, transmitted through the selection surface, and thereafter directed to the pupil of the observer.

Abstract: An objective optical system has at least three lens units having positive, negative, and positive optical powers. A fourth lens unit can have either negative or positive optical power. The system satisfies at least one of: (A) 0.15≦&bgr;4W/FLWobj≦0.28, where &bgr;4W represents image forming magnification of fourth lens unit at wide angle end, and FLWobj represents focal length of the system at wide angle end, and (B) the third lens unit being a biconvex lens element which satisfies the relationship Nd3≧1.6, where Nd3 represents d-line refractive index of lens material of the biconvex lens element. The system can also satisfy the relationship 0.038≦1/FL1≦0.068, where FL1 represents focal length of first lens unit. The third lens unit can have at least one aspherical surface which, relative to a height Y in an optional direction perpendicular to the optical axis such that 0.7Ymax<Y<Ymax, satisfies the relationship −0.

Abstract: An image forming optical system has an illumination light source for forming an illumination light beam, a reflective type image forming device for optically modulating the illumination light beam into an image-carrying light beam, a light beam selecting surface for selectively reflecting or transmitting a light beam shone thereon according to the angle of incidence thereof, and deflecting means disposed between the light beam selecting surface and the reflective type image forming device. One of the illumination light beam and the image-carrying light beam is shone on the light beam selecting surface at an angle of incidence larger than the critical angle so as to be reflected therefrom, and the other is shone on the light beam selecting surface at an angle of incidence smaller than the critical angle so as to be transmitted therethrough, so that these two light beams are separated. The above-mentioned angles of incidence are set appropriately by the deflecting means.

Abstract: In an image display apparatus, between a reflection-type liquid crystal display panel and a light source for supplying illumination light thereto, a half mirror is disposed at an angle. In addition, in the optical path of the light reflected from the liquid crystal display panel and then reflected from the half mirror, a concave mirror is disposed, and, in the optical path of the light reflected from the concave mirror and then transmitted through the half mirror, a polarizing plate is disposed so that, out of the light reflected from the liquid crystal display panel, only the light that conveys an image is directed to an observer's eye. Alternatively, a polarization separation mirror is disposed in place of the half mirror, and a quarter-wave plate is disposed between the polarization separation mirror and the concave mirror instead of using the polarizing plate.

Abstract: An image display apparatus is provided with a screen having retro-reflectivity, a liquid crystal display device displaying an image, a projection optical system projecting the light of the liquid crystal display device onto the screen, and a beam magnifier located close to the screen and magnifying the light beams, included in the projected light, expressing individual points of the image. The beam magnifier is composed of a diffraction optical element or a diffusing plate, and magnifies each light beam so that the magnification is larger in the direction of the horizontal field of view than in the direction of the vertical field of view. When images having parallax are provided for the left and right eyes, an upper limit of the magnification of the light beams is set in consideration of the distance between the left and right eyes to prevent cross-talk.

Abstract: An image display apparatus is provided for providing a virtual image to an observer. The image display apparatus includes an image display unit, an eyepiece optical system, and a container. The image display unit is for providing modulated light corresponding to the virtual image. The eyepiece optical system is for directing the modulated light from the image display unit to one or both of the observer's eyes. The container is for supporting the image display unit on an edge portion of the eyepiece optical assembly.

Abstract: An information display device provided with a prism having at least two reflecting surfaces arranged in facing each other and a hologram surface formed of a reflection-type hologram. And at least one of the two reflecting surfaces is a light-beam-selective surface that selectively transmits or reflects light in accordance with its incident angle. An image light emitted from an image display means enters the prism, and is reflected between the reflecting surfaces, and then is diffractively reflected on the hologram surface, and, after being transmitted through the light-beam-selective surface, is directed to an observer's pupil.

Abstract: An image processing system has an image acquisition unit, a document inclination acquisition unit and a correction unit. The image acquisition unit acquires a plurality of segment images by segment image sensing on a plurality of image sensing directions of a surface of an image sensing target while an image sensing device is stationary in a fixed standard direction. The document inclination acquisition unit acquires the inclination of the surface of the image sensing target relative to the standard direction. The correction unit corrects the plurality of obtained segment images in accordance with the inclination of the surface of the image sensing target and the inclination in the image sensing direction relative to the standard direction.

Abstract: An objective optical system has at least three lens units having positive, negative, and positive optical powers. A fourth lens unit can have either negative or positive optical power.

Abstract: An objective optical system has at least three lens units having positive, negative, and positive optical powers. A fourth lens unit can have either negative or positive optical power. The system satisfies at least one of: (A) 0.15≦&bgr;4W/FLWobj≦0.28, where &bgr;4W represents image forming magnification of fourth lens unit at wide angle end, and FLWobj represents focal length of the system at wide angle end, and (B) the third lens unit being a biconvex lens element which satisfies the relationship Nd3≧1.6, where Nd3 represents d-line refractive index of lens material of the biconvex lens element. The system can also satisfy the relationship 0.038≦1/FL1≦0.068 where FL1 represents focal length of first lens unit. The third lens unit can have at least one aspherical surface which, relative to a height Y in an optional direction perpendicular to the optical axis such that 0.7Ymax<Y<Ymax, satisfies the relationship −0.

Abstract: An image display apparatus has a signal input portion for receiving an image signal, an image compensator for electrically compensating the image signal for distortion so that a left and a right image displayed in an observer's left and right eyes have identical distortion and then outputting a left and right image signal that correspond to the left and right images, a signal switcher for switching between the left and right image signals output from the image compensator so as to output the left and right images alternately chronologically, a single two-dimensional image display device for displaying a two-dimensional image in accordance with the image signal output from the signal switcher, a pair of left and right eyepiece optical systems for directing image light exiting from the two-dimensional image display device to the observer's left and right eyes so that the two-dimensional image is displayed as a virtual image in the observer's eyes, and an optical path switcher for time-divisionally switching opt

Abstract: A color projection display apparatus has a white light source, splitting means, a reflective color display device and projecting means. The splitting means splits a white luminous flux from the white light source into a plurality of luminous fluxes of different wavelength ranges, and from which luminous fluxes corresponding to the wavelength ranges exit in different directions. The reflective color display device modulates and reflects the luminous fluxes corresponding to the wavelength ranges which luminous fluxes exit from the splitting means and are incident from different directions. The projecting means projects the luminous fluxes modulated by the reflective color display device as image light. The luminous fluxes modulated and reflected by the reflective color display device are incident on the projecting means after being again transmitted by the splitting means.

Abstract: A scanning-type image viewing optical system has a light source for emitting luminous flux; a main scanning means for scanning luminous flux in a first direction; a sub-scanning means for scanning luminous flux in a second direction different from the first direction; and an eyepiece lens for directing luminous flux scanned by the two scanning means to the pupil of an observer, wherein the main scanning means has a conjugate relationship with the pupil position of the observer via the eyepiece lens, and when the pupil diameter, i.e., the luminous flux diameter of the incident luminous flux at the pupil position of the observer, is designated d and the main scan diameter, i.e., the luminous flux diameter exiting the main scanning means, is designated d', the conjugate magnification .beta. calculated by d/d' satisfies the conditional equation .beta..ltoreq.0.85.