Abstract: The present invention relates to a high-performance image-forming optical system made compact and thin by folding an optical path using reflecting surfaces arranged to minimize the number of reflections. A prism member 10 has a first entrance surface 11, first to fourth reflecting surfaces 12 to 15, and a first exit surface 16. An optical path incident on the first reflecting surface 12 and an optical path reflected from the second reflecting surface 13 form intersecting optical paths. An optical path incident on the third reflecting surface 14 and an optical path reflected from the fourth reflecting surface 15 form intersecting optical paths. At least either one of the first reflecting surface 12 and the second reflecting surface 13 and at least either one of the third reflecting surface 14 and the fourth reflecting surface 15 have a rotationally asymmetric curved surface configuration that gives a power to a light beam and corrects aberrations due to decentration.

Abstract: A lightweight and homogeneous optical element exhibiting favorably weak birefringence and hygroscopicity as well as superior productivity and producing minimal chromatic aberrations is formed by using an organic-inorganic composite material having both the properties of a glass material and those of a plastic material. The optical element has at least one entrance refracting surface and at least one exit refracting surface. The optical element is formed from an organic-inorganic composite material having an inorganic phase dispersed in the three-dimensional network (matrix) of an organic phase.

Abstract: The present invention relates to a high-performance image-forming optical system made compact and thin by folding an optical path using reflecting surfaces arranged to minimize the number of reflections. A prism member 10 has a first entrance surface 11, first to fourth reflecting surfaces 12 to 15, and a first exit surface 16. An optical path incident on the first reflecting surface 12 and an optical path reflected from the second reflecting surface 13 form intersecting optical paths. An optical path incident on the third reflecting surface 14 and an optical path reflected from the fourth reflecting surface 15 form intersecting optical paths. At least either one of the first reflecting surface 12 and the second reflecting surface 13 and at least either one of the third reflecting surface 14 and the fourth reflecting surface 15 have a rotationally asymmetric curved surface configuration that gives a power to a light beam and corrects aberrations due to decentration.

Abstract: The invention relates to a small-format display optical system using a reflection type image device as an image display device and capable of displaying bright, high-resolution images. The display optical system comprises a reflection type display device 3 for displaying an image, an illumination light source 5 for illuminating the reflection type display device 3, an illumination optical system for guiding light from the illumination light source 5 to the reflection type disply device 3, a relay optical system 21 for projection of an image appearing on the reflection type display device 3 and an eyepiece optical system 22 acting to converge a light beam from the relay optical system 21 toward the eyeball of a viewer. An image projected through the relay optical system 21 is formed near the eyepiece optical system 22.

Abstract: The invention relates to a binocular image display system which can follow changes in the viewing position of a viewer, if any, without superposition of the right-eye pupil and the left-eye pupil, so that the viewer can view 3D images, etc. The image display system comprises an image display device 3, an illumination light source 4, an illumination optical system, a relay optical system 31 and an eyepiece optical system 32. The image display device 3 is a single device adapted to display left-eye and right-eye images alternately. The illumination light source 4 comprises a light source that is changed over to separate illumination areas depending on the displayed left-eye and right-eye images so that the illumination areas can be moved. The exit pupil comprises a pair of left and right exit pupils 1L and 1R determined depending on the illumination areas of the illumination light source.

Abstract: The present invention relates to a high-performance image-forming optical system made compact and thin by folding an optical path using reflecting surfaces arranged to minimize the number of reflections. A prism member 10 has a first entrance surface 11, first to fourth reflecting surfaces 12 to 15, and a first exit surface 16. An optical path incident on the first reflecting surface 12 and an optical path reflected from the second reflecting surface 13 form intersecting optical paths. An optical path incident on the third reflecting surface 14 and an optical path reflected from the fourth reflecting surface 15 form intersecting optical paths. At least either one of the first reflecting surface 12 and the second reflecting surface 13 and at least either one of the third reflecting surface 14 and the fourth reflecting surface 15 have a rotationally asymmetric curved surface configuration that gives a power to a light beam and corrects aberrations due to decentration.

Abstract: A high-performance image-forming optical system made compact and thin by folding an optical path using reflecting surfaces arranged to minimize the number of reflections. The image-forming optical system has a single prism. When image-side three surfaces of the prism are defined as a surface A, a surface B and a surface C in order from the image plane side thereof, at least one of the surfaces B and C has a rotationally asymmetric curved surface configuration that gives a power to a light beam and corrects aberrations due to decentration. The optical system leads light rays from an object to the image plane without forming an image in the prism and has a pupil in the prism. The surface A is a transmitting surface through which rays exit from the prism. The surfaces B and C are internally reflecting surfaces, which are positioned to face each other to form a Z-shaped optical path.

Abstract: The invention relates to a display system wherein a Fresnel lens that forms an eyepiece optical system is curved to correct for decentration aberration, whereby a display screen can be wholly observed even in a decentered state. In the display system, an object image is projected via a relay optical system 2 near the eyepiece optical system 1 so that the exit pupil E1 of the relay optical system 2 is projected via the eyepiece optical system 1 onto an observer's pupil position E0. The eyepiece optical system comprises an optical element having a Fresnel surface. The eyepiece optical system 1 and relay optical system 2 are located such that an axial chief ray emerging from the relay optical system 2 is obliquely incident on the eyepiece optical system 1. The axial chief ray is defined by a light ray emerging from the center of the object, and passing through the relay optical system 2 and then through the center of the pupil E1 of the relay optical system 2.

Abstract: The invention relates to an imaging system 50 wherein, without recourse to any large-size pupil relay optical system, a plurality of minute imaging optical systems are arranged in rows and columns to pick up pixel images of a divided fundus through separate imaging optical systems, so that a fundus image is synthesized from the thus picked up pixel images as well as an identity authentication system. A plurality of imaging units 101, 101 and 103 comprising imaging lenses 11, 12 and 13 and imaging devices 31, 32 and 33 located on their image planes are two-dimensionally arranged in rows and columns. An illumination device for illumination 4 of a subject E in a direction along the optical system of each imaging unit is provided, wherein each of the optical axes 21, 22 and 23 of the respective imaging units is defined by an axis that passes through a common object point P at an imaging position and the center of each imaging lens.

Abstract: The invention provides a small-sized projection optical apparatus which uses a decentered prism as a projection optical system and in which some contrivances are provided to how to introduce illumination light into a reflection type display device. The projection optical apparatus comprises a reflection type display device 1, a projection optical system 2 for providing projection of an image displayed thereon and an illumination light source for illuminating a display surface. The projection optical system 2 comprises a catadioptric optical element 10 having two rotationally asymmetric curved reflecting surfaces 12, 13 having positive power.

Abstract: The invention provides a projection optical apparatus that is fast and of satisfactory illumination efficiency albeit being of simple construction and compact size by making use of a diffuse hologram that projects the exit pupil of a projection optical system onto a viewing position and magnifying the thus projected exit pupil image to a limited area. The apparatus comprises at least three projection optical systems 1R, 1G and 1B for magnifying and projecting an image appearing on a display device, and further comprises a concave mirror 2, 2′ for projecting exit pupils 8R, 8G and 8B of the projection optical systems onto a viewer side and a diffusing plate 3 comprising a transmission hologram, which is located near to images projected through the projection optical systems for magnifying the images of the exit pupils 8R, 8G and 8B of the projection optical system upon projected by the concave mirror 2, 2′.

Abstract: The invention provides a small-sized projection optical apparatus which uses a decentered prism as a projection optical system and in which some contrivances are provided to how to introduce illumination light into a reflection type display device. The projection optical apparatus comprises a reflection type display device 1, a projection optical system 2 for providing projection of an image displayed thereon and an illumination light source for illuminating a display surface. The projection optical system 2 comprises a catadioptric optical element 10 having two rotationally asymmetric curved reflecting surfaces 12, 13 having positive power.

Abstract: The present invention relates to an image display apparatus, e.g. a head-mounted image display apparatus, in which an image from a single image display device is led to two eyes without using a half-mirror, thereby allowing observation of a bright image. The image display apparatus has an optical path distributing mirror 1 for distributing the image of a single display device 10 to an optical path for a right eye and an optical path for a left eye, and an ocular prism 2R for the right eye and an ocular prism 2L for the left eye, which are placed on the right- and left-hand sides, respectively, of the optical path distributing mirror 1.

Abstract: A high-performance image-forming optical system made compact and thin by folding an optical path using reflecting surfaces arranged to minimize the number of reflections. The image-forming optical system has a single prism. When image-side three surfaces of the prism are defined as a surface A, a surface B and a surface C in order from the image plane side thereof, at least one of the surfaces B and C has a rotationally asymmetric curved surface configuration that gives a power to a light beam and corrects aberrations due to decentration. The optical system leads light rays from an object to the image plane without forming an image in the prism and has a pupil in the prism. The surface A is a transmitting surface through which rays exit from the prism. The surfaces B and C are internally reflecting surfaces, which are positioned to face each other to form a Z-shaped optical path.

Abstract: The invention relates to a two-dimensional optical scanner in which distortions upon scanning can be reduced in simplified construction and a compact, energy-saving image display system using the same. The two-dimensional optical scanner comprises a light source 10, a scanner unit of gimbal structure for scanning a light beam therefrom in a two-dimensional direction and a scanning optical system 20 comprising a non-rotationally symmetric surface having an action of correction of a distortion upon scanning of the scanned light beam. The scanning optical system 20 comprises a decentered prism comprising an entrance surface 24, a first reflecting surface 23, a second reflecting surface 22 and an exit surface 21. The respective surfaces of the prism are located such that in that prism, a light beam from the entrance surface 24 toward the first reflecting surface 23 crosses a light beam from the second reflecting surface 22 toward the exit surface 21.

Abstract: The invention relates to a two-dimensional optical scanner in which distortions upon scanning can be reduced in simplified construction and a compact, energy-saving image display system using the same. The two-dimensional optical scanner comprises a light source 10, a scanner unit 2 of gimbal structure for scanning a light beam therefrom in a two-dimensional direction and a scanning optical system 20 comprising a non-rotationally symmetric surface having an action of correcting a distortion upon scanning of the scanned light beam. The scanning optical system 20 comprises a decentered prism 20 comprising an entrance surface 22, at least one reflecting surface 23 and an exit surface 21. At least one of the entrance surface, reflecting surface and exit surface comprises a non-rotationally symmetric surface.

Abstract: The invention provides an optical system that enables focal length, image-formation position, etc. to be controlled in simple construction by bending the optical system to shift a light beam passing through it and so making use of an arbitrary portion of the optical system. In an image-formation optical system comprising at least two optical elements S1 and S2, the at least two optical elements S1 and S2 are mutually decentered to vary the properties such as magnification.

Abstract: An optical path splitting element for splitting a light beam from a single object into at least two optical paths is made compact in size by using a three-dimensional optical system and given a power to reduce the number of components thereof. An image display apparatus uses the optical path splitting element. The optical path splitting element has a prism member having an entrance surface through which the light beam from the object enters the prism member, at least one reflecting surface reflecting the light beam within the prism member, and an exit surface through which the light beam exits the prism member. The prism member has at least one rotationally asymmetric surface. At least one optical functional surface is a discontinuous surface formed from at least two surfaces adjacent to each other. The other optical functional surfaces are common to the at least two optical paths.

Abstract: The invention relates to a projection viewing system of simplified construction and high illumination efficiency, which enables at least two of images varying with viewing directions to be simultaneously displayed in a viewable fashion. The system comprises display devices 1L and 1R for displaying images, projection optical systems 2L and 2R for magnifying and projecting images 3L and 3R displayed on the display devices 1L and 1R, a diffusing plate 5 located in the vicinity of images projected through the projection optical systems 2L and 2R and an eyepiece optical system 4 for projecting exit pupils of the projection optical systems 2L and 2R on the positions of the eyeballs of a viewer. The diffusing plate 5 has an angle of diffusion of up to 20° at full width half maximum.

Abstract: The invention relates to a compact electronic camera which enables an electronic image to be displayed on a two-dimensional display element while it is phototaken or after it has been phototaken, so that the image can be magnified and displayed by a compact magnifying optical system constructed of a curved reflecting mirror to view a phototaken image of high precision. An electronic camera for photoelectrically converting a subject image formed by a phototaking optical system 2 into an electronic image to be recorded comprises a two-dimensional display element 4 for displaying an electronic image during or after phototaking and a magnifying optical system 5 for magnifying an image displayed on the two-dimensional display element 4 in the form of a virtual image. The magnifying optical system 5 is constructed of at least one curved reflecting mirror 26 and a surface 28 having a combined reflecting and transmitting action.