Abstract: An exposure apparatus (PE1) and exposure method for use in photolithographically manufacturing devices such as semiconductor devices, image pickup devices, liquid crystal display devices and thin film magnetic heads. The apparatus is capable of transferring onto a substrate (W) the image of a pattern on a reticle (R) and includes a light source (2) capable of supplying an exposure energy beam (IL) with a wavelength under 200 nm, and an illumination optical system arranged to receive the exposure energy beam from said light source. The illumination optical system is designed to guide the exposure energy beam to the reticle. The apparatus also includes a projection optical system (PL) arranged between the reticle and the substrate. The projection optical system is capable of forming an image of the reticle pattern onto the substrate based on the exposure energy beam passing through the reticle.

Abstract: According to one aspect the invention, a panoramic imaging arrangement is provided which includes at least a first lens block including a convex reflective surface and a transparent component. The convex reflective surface has a substantially vertically extending axis of revolution and is capable of receiving light from a 360° surrounding panoramic scene, and reflecting the light for further manipulation. The transparent component covers the convex reflective surface. The convex reflective surface is thereby protected from environmental conditions which may otherwise result in damage to the convex reflective surface.

Abstract: The present invention relates to a projection exposure apparatus (10) for and method of imaging a reticle (R) having patterned surface onto a substrate (W) in photolithographic processes for manufacturing a variety of devices. The invention further relates to an optical system (C) having a folding member(M1) suited to the projection exposure apparatus, and a method for manufacturing the optical system. The projection exposure apparatus comprises an illumination optical system (IS) and a reticle stage (RS) capable of holding the reticle so the normal line to its patterned surface is in the direction of gravity. The apparatus also includes a substrate stage (WS) capable of holding the substrate with its surface normal parallel to the direction of gravity. The optical system includes a first imaging optical system (A) comprising a concave reflecting mirror and a dioptric optical member arranged along a first optical axis. The first imaging optical system (A) forms an intermediate image of the patterned surface.

Abstract: According to one aspect the invention, a panoramic imaging arrangement is provided which includes at least a first lens block including a convex reflective surface and a transparent component. The convex reflective surface has a substantially vertically extending axis of revolution and is capable of receiving light from a 360° surrounding panoramic scene, and reflecting the light for further manipulation. The transparent component covers the convex reflective surface. The convex reflective surface is thereby protected from environmental conditions which may otherwise result in damage to the convex reflective surface.

Abstract: A mirror projection system for use in a step-and-scan lithographic projection apparatus in which a mask pattern (15) is repetitively scan-imaged on a number of areas of a substrate (20) by means of a beam (b) of EUV radiation having a circular segment-shaped cross-section. This system, which is easier to manufacture at lower cost than a projection system with six or more imaging mirrors, has only five imaging mirrors (5-9) with a good numerical aperture and an acceptable image-ringfield width. An EUV lithographic projection apparatus provided with the new projection system has a wafer throughput which is approximately 50% higher than that of an apparatus provided with a six-mirror projection system. Moreover, it has a compact construction.

Abstract: An exposure apparatus includes a projection optical system of catadioptric type, and an optical element disposed on a reciprocating light path of the projection optical system, the optical element being movable to correct at least one of spherical aberration, astigmatism, and curvature of field of the projection optical system.

Abstract: A lens design having two concave mirrors or Mangins and a turning mirror is disclosed. The optical axis of the concave elements are coplanar and intersect on a turning mirror, and the normal to the surface of the turning mirror bisects the angle between the two optical axis.

Abstract: According to one aspect of the invention there is provided a panoramic imaging arrangement comprising lens block and a system of lenses. The lens block has a substantially vertical axis of revolution and is capable of receiving light from a first, 360° surrounding panoramic scene. The system of lenses has a vertical axis of revolution substantially coinciding with the axis of revolution of the lens block and is positioned to receive light from a second scene which is at least partially located above the first, surrounding panoramic scene, and projecting the light from the second scene.

Abstract: According to one aspect of the invention there is provided a panoramic imaging arrangement comprising a transparent component and a reflective material. The transparent component has a first surface about a vertical axis of revolution, a second surface about the axis of revolution, and an opening formed therein to define a third, internal surface about the axis of revolution. The third surface has a concave profile in a plane of the axis of revolution. The reflective material is located on the second surface to provide a reflective surface against the second surface. The first surface, the reflective surface and the third surface are positioned relative to one another so that light from a 360° surrounding panoramic scene enters the transparent component through the first surface, whereafter the light is reflected from the reflective surface, whereafter the light exits the transparent component through the third surface.

Abstract: A light energy efficient and low cost optical system for providing uniform illumination of a light valve. The light source is an extended source generally emitting a non-uniform spatial distribution of light power. The source light is focused into the entrance end of a light transmitting tunnel having reflecting interior wall surfaces and having cross sectional and length dimensions chosen to deliver, at the exit end of the tunnel, light which is substantially uniform is power distribution, over the surface area of the exit end, due multiple reflections from the tunnel walls. The exiting light is advantageously used to uniformly illuminate a light valve. The invention includes a combination of mirrors arranged about the source light to most effectively collect and direct the light.

Abstract: A reflective telecentric lens which uses an on-axis type concave mirror in a pseudo-off-axis manner to avoid blockage of a portion of the field of view. The concave mirror used in a pseudo-off-axis manner permits the telecentric stop, imaging lens, and film or an electronic detector to be moved outside of the field of view.

Abstract: A catadioptric reduction projection optical system having a first lens unit having negative refractive power and widening a light beam from a reticle, a prism type beam splitter for transmitting therethrough a light beam from the first lens unit, a concave reflecting mirror for returning the light beam emerging from the beam splitter to the beam splitter while converging it, and a second lens unit having positive refractive power and converging the light beam returned to the beam splitter and reflected by the beam splitter, and forming the reduced image of a pattern on the reticle on a wafer.

Abstract: Disclosed is a photovoltaic module including a plurality of concentrators each having a light-incident plane and a reflection plane, and photo detectors. Each photo detector is in contact with one of the concentrators. The module is capable of effectively trapping light and effectively generating power throughout the year even if the module is established such that sunlight at the equinoxes is made incident on the light-incident planes not in a perpendicular manner but instead obliquely, for example, in the case where the module is established in contact with a curved plane of a roof, or the like.

Abstract: An image pickup optical system has an optical element of a transparent, optical material including an entrance surface, at least one reflective surface, and an exit surface. The optical element has an optical power, the image pickup optical system has an image pickup element including a plurality of pixels. On the image pickup element an image is formed by light from an object through the optical element. The optical material is a material having an index change amount &Dgr;n from an absolute dry condition at the temperature of 50° C. to saturation under a circumstance of the temperature being 50° C.

Abstract: Most camera systems only record an image from a limited viewing angle. A new panoramic camera apparatus is disclosed that instantaneously captures a 360 degree panoramic image. In the camera device, virtually all of the light that converges on a point in space is captured. Specifically, in the camera of the present invention, light striking this point in space is captured if it comes from any direction, 360 degrees around the point and from angles 50 degrees or more above and below the horizon. The panoramic image is recorded as a two dimensional annular image. Furthermore, various different systems for displaying the panoramic images and distributing the panoramic images. Specifically, methods and apparatus for digitally performing a geometric transformation of the two dimensional annular image into rectangular projections such that the panoramic image can be displayed using conventional methods such as printed images and televised images.

Abstract: Disclosed is a photovoltaic module including a plurality of concentrators each having a light-incident plane and a reflection plane, and photo detectors each being in contact with one of the concentrators, which is capable of effectively trapping light and effectively generating power throughout the year even if the module is established such that sunlight at the equinoxes is made incident on the light-incident planes not perpendicularly but obliquely from the right, upper side, for example, in the case where the module is established in contact with a curved plane of a roof or the like.

Abstract: An optical pickup includes a light source emitting a laser beam and an optical path changing unit altering a traveling path of an incident beam. An objective lens, disposed on an optical path between the optical path changing unit and an optical disk, focuses the incident beam from the light source to form a light spot on the optical disk of the objective lens. The optical pickup further includes a photodetector and an detecting-correcting unit, arranged on the optical path between the optical path changing unit and the objective lens, performing at least one of detecting the thickness of the optical disk and correcting aberration caused by thickness variations of the optical disk. The objective lens includes a first transmitting portion divergently transmitting an incident beam, where the first transmitting portion is at a relatively near-axis region from an optical axis of the objective lens.

Abstract: A catoptric reduction projection optical system (5) is provided with a first catoptric optical system (10) that images an object (R) in first (object) plane (OP) into a second plane (12) and forming an intermediate image (II) therein, and a second catoptric optical system (20) that images the intermediate image in the second plane onto a third (image) plane (IP), thereby and forming a reduced image of the object in the first (object) plane onto the third (image) plane. The first catoptric optical system comprises a first mirror pair comprising two reflective mirrors (M1, M2). The second catoptric optical system comprises a second mirror pair comprising a convex mirror (M3) and a concave mirror (M4). The system also preferably satisfied a number of design conditions.

Abstract: A composite display apparatus has a display device for displaying image information, a display optical system for guiding light from the display device to the eye of an observer, and an image pickup optical system for focusing light from the outside on an image pickup device. An optical axis of the image pickup optical system is substantially aligned with an axis that is an extension of the eye-ball optical axis in an optical path of the display optical system. The apparatus further has an optical path separating element for separating an optical path of the image pickup optical system from the optical path of the display optical system. Each of the display optical system and the image pickup optical system has a plurality of decentered reflective surfaces having curvature. The light from the display device is alternately folded in directions along the eye-ball optical axis by the plurality of reflective surfaces of the display optical system to be guided to the eye.

Abstract: A very compact, high numerical aperture, high resolution, ultra-wide field of view concentric scanning optical sensor. The concentric scanning optical sensor includes a scanning half ball lens having a flat reflective rear surface, outer and inner shell lenses, and a linear focal surface array. The outer shell lens and linear inner shell lens are concentrically disposed about the center of the scanning half ball lens. The linear focal surface array is disposed along a focal surface of the inner shell lens. The scanning optical sensor may also use a full spherical ball with multiple reflecting surfaces to allow for multiple facet scanning.

Abstract: A reflection and refraction optical system includes a polarization beam splitter, a concave mirror, a lens group and a quarter waveplate, wherein an additional waveplate is provided to transform S-polarized light from the polarization beam splitter into circularly polarized light.

Abstract: According to one aspect of the invention there is provided a panoramic imaging arrangement comprising a transparent component and a reflective material. The transparent component has a first surface about a vertical axis of revolution, a second surface about the axis of revolution, and an opening formed therein to define a third, internal surface about the axis of revolution. The third surface has a concave profile in a plane of the axis of revolution. The reflective material is located on the second surface to provide a reflective surface against the second surface. The first surface, the reflective surface and the third surface are positioned relative to one another so that light from a 360° surrounding panoramic scene enters the transparent component through the first surface, whereafter the light is reflected from the reflective surface, whereafter the light exits the transparent component through the third surface.

Abstract: A catadioptric projection lens comprising a first lens group (G1) disposed along a first optical axis (16a), a mirror (18) which creates a second optical axis (16b), a beam splitter (20) which creates a third optical axis (16c), a second lens group (G2) including a concave mirror (L22) disposed along the third optical axis on one side of the beam splitter, and a third lens group (G3) disposed along the third optical axis on the side of the beam splitter. The first and third optical axes are parallel, a configuration which reduces aberrations arising from gravitational deformation of the lens elements, when the first and third axes are aligned with the direction of gravity.

Abstract: The present invention relates to a projection exposure apparatus (10) for and method of imaging a reticle (R) having patterned surface onto a substrate (W) in photolithographic processes for manufacturing a variety of devices. The invention further relates to an optical system (C) having a folding member (M1) suited to the projection exposure apparatus, and a method for manufacturing the optical system. The projection exposure apparatus comprises an illumination optical system (IS) and a reticle stage (RS) capable of holding the reticle so the normal line to its patterned surface is in the direction of gravity. The apparatus also includes a substrate stage (WS) capable of holding the substrate with its surface normal parallel to the direction of gravity. The optical system includes a first imaging optical system (A) comprising a concave reflecting mirror and a dioptric optical member arranged along a first optical axis. The first imaging optical system (A) forms an intermediate image of the patterned surface.

Abstract: A near-field optical or MO data storage system uses an optical focusing device for focusing an incident optical beam to a small size focal spot. The optical focusing device includes an optically transmissive body which is defined by a generally flat incident surface, a flat, bottom surface disposed opposite and parallel to the incident surface, and a reflective side coated with a reflective layer for reflecting the optical beam through the body toward the bottom surface. The bottom surface defines a focal plane on which the focal spot is formed, for generating a localized evanescent field. The focal spot is located along a central axis P, in very close proximity to the data storage disk, such that the localized evanescent field interacts with the disk, for enabling data to be transduced to and from the disk by effecting near field coupling. An electro-magnetic coil or coil assembly, can optionally be formed on the bottom surface, co-axially with the focal spot, for generating a desired write magnetic field.

Abstract: The invention is directed to a catadioptric microlithographic reduction objective having two concave mirrors (21, 23) facing toward each other. The concave mirrors have a symmetrical configuration and a central bore. Lenses (24 to 60) are mounted downstream of the mirrors (21, 23) on the light path toward the image plane (61). Preferably, lenses (15 to 20) are moved at the object end forward into the intermediate space between the mirrors (21, 23) in the region of the central bore. The light path between the concave mirrors can then preferably be free of lenses. The formation of an intermediate image (Z) downstream of the mirrors (21, 23) affords especially good correction possibilities.

Abstract: In a device for directing light longitudinally forwardly, the combination comprising a light source, and a protective, transparent envelope extending about the light source; a drum lens having a body extending about the light source and envelope, for refracting light from the source; a light reflector extending about the drum lens body, for forwardly and convergently re-directing refracted light received from the drum lens body; and a correcting lens for receiving a collimating re-directed light screened from the reflector.

Abstract: An optical imaging system especially for microlithography includes a first imaging system forming an intermediate image of an object, and a second imaging system forming, on a surface, an image of the intermediate image. A reflective surface directs light from the first imaging system to the second imaging system. An aspherical corrective optical surface is located at or near the location of the intermediate image for correcting aberrations such as high-order distortion, aberrations due to accumulation of manufacturing tolerances, and spherical aberration. The first imaging system comprises a positive power refractive element and a concave mirror. The second imaging system comprises refractive elements and no concave mirror.

Abstract: It is an object to provide a high-performance and compact exposure apparatus which can perform a projection exposure operation with satisfactory optical performance by using a plurality of compact projection optical systems each capable of ensuring a sufficient working distance and having excellent imaging performance, while preventing a decrease in throughput even in a large exposure area. An exposure apparatus for projecting and exposing an image of a mask onto a plate while moving a mask and a plate has a first projection optical system and a second projection optical system each of which is real-size and both-side telecentric and forms the erect image of the mask on the plate. The first or second projection optical system has a refraction optical system having a positive refracting power, and a concave reflecting mirror for reflecting a light beam from the refraction optical system toward the refraction optical system.

Abstract: A zoom optical system and an image pickup apparatus using the same are disclosed. The zoom optical system comprises a first optical unit having a refractive power, the first optical unit having a reflecting surface, a second optical unit having a refractive power, and a driving portion for moving a light receiving surface which receives light from an object through the first optical unit and the second optical unit. The zoom optical system performs variation of magnification by moving at least one of the first optical unit and the second optical unit, and a deviation of a focus position due to the variation of magnification is corrected by the light receiving surface being moved by the driving portion.

Abstract: A catadioptric reduction projection optical system having a first lens unit having negative refractive power and widening a light beam from a reticle, a prism type beam splitter for transmitting therethrough a light beam from the first lens unit, a concave reflecting mirror for returning the light beam emerging from the beam splitter to the beam splitter while converging it, and a second lens unit having positive refractive power and converging the light beam returned to the beam splitter and reflected by the beam splitter, and forming the reduced image of a pattern on the reticle on a wafer.

Abstract: A catoptric reduction projection optical system (8), exposure apparatus (EX) including same, and a method using same for forming in a second plane (WP) a reduced image of an object (R) in a first plane (RP). The projection optical system includes, in order along a folded optical path on in optical axis (AX), from the first plane to the second plane, a first mirror (M1) having a concavely shaped reflecting surface and a first vertex, a second mirror (M2) having a second vertex, a third mirror (M3) having a convexly shaped reflecting surface and a third vertex, a single aperture stop (AS), and a fourth mirror (M4) having a concavely shaped reflecting surface and a fourth vertex. The projection optical system also preferable satisfies a number of design conditions.

Abstract: A catadioptric reduction projection optical system having a first lens unit having negative refractive power and widening a light beam from a reticle, a prism type beam splitter for transmitting therethrough a light beam from the first lens unit, a concave reflecting mirror for returning the light beam emerging from the beam splitter to the beam splitter while converging it, and a second lens unit having positive refractive power and converging the light beam returned to the beam splitter and reflected by the beam splitter, and forming the reduced image of a pattern on the reticle on a wafer.

Abstract: Provided with an optical system which is applicable to an exposure apparatus used in the manufacture of semiconductors and includes a combination of a spherical mirror having a function of refraction and lenses for astigmation control, using a CaF.sub.2 lens as the last lens, thereby making it possible to use a light source operating at a short wavelength and a wide bandwidth, enhance the life of the optical system, and transfer the enlarge pattern of a mask onto the wafer for realizing fine line width.

Abstract: A catadioptric optical system (10, 110) capable of forming an image of an object. The system comprises a first optical axis (Z.sub.1) having a first end (12) and a second end (14), with a concave mirror (M.sub.C) arranged at the first end. A second surface (P.sub.2) orthogonal to the first optical axis is provided at the second end. A reflective surface (M) is arranged between the concave mirror and the second surface. A first imaging optical system (A) comprising a first plurality of lenses (L.sub.1 -L.sub.4) is arranged between the reflective surface and the concave mirror. A second imaging optical system (B) comprising a second plurality of lenses (L.sub.5 -L.sub.9) is arranged between the reflective surface and the second surface. The system further includes a second optical axis (Z.sub.2) intersecting the first optical axis at the reflective surface and having a first surface (P.sub.1) disposed along and orthogonal to the secondary optical axis.

Abstract: A high-performance and low-cost image-forming optical system made compact and thin by folding an optical path using reflecting surfaces having power. The optical system has a plurality of reflecting surfaces having power. Among the reflecting surfaces, a reflecting surface (12) of negative power is placed closest to the object side, and a reflecting surface (22) of positive power is placed closer to the image side than the reflecting surface (12). At least one reflecting surface (13) is provided between the reflecting surface (12) and the reflecting surface (22). An axial principal ray (1) incident on the reflecting surface (13) satisfies the condition of 45.degree.<.vertline..theta..vertline., where .theta. is the angle formed between the axial principal ray and a line normal to the reflecting surface (13) in the decentration direction at a point where the axial principal ray (1) intersects the reflecting surface (13).

Abstract: A catadioptric reduction projection optical system (10, 30) capable of forming a reduced image of a pattern of a reticle (R) on a wafer (W) by scanning the reticle and wafer in a scanning direction (12, 14). The system comprises, in order from a first surface (OP) to a second surface (IP) along a folded optical axis (A), a first optical system (G1) having positive refracting power, and a beam splitter (BS) having a transmissoreflective surface and a reflection optical path and a transmission optical path. The beam splitter is arranged such that the plane of incidence, defined by the folded optical axis, includes the scanning direction. The system also includes a second optical system (G2) comprising a single concave mirror (M.sub.C) arranged in one of the reflection optical path and transmission optical path, and a third optical system. The latter has negative refracting power and includes a reflective plane surface (M.sub.P).

Abstract: A rear-view mirror for a vehicle has a convex reflecting surface composed of a plurality of distinct curved surfaces each having a selected shape that are smoothly joined with each other with a continuously varying average curvature. The average curvature increases gradually along the vertical direction from the top to the bottom of the mirror and along the transverse horizontal direction away from the body of the vehicle. The mirror provides a wide viewing around both sides and of the rear of the vehicle without blind spots and provides a clear image with little distortion that is visually acceptable to a driver.

Abstract: A catadioptric reduction optical system capable of imaging an object by scanning in a scanning direction. The system comprises, objectwise to imagewise, a first optical system, a beam splitter, and a second optical system arranged adjacent the beam splitter opposite the image side thereof. The second optical system includes at least one concave mirror. The system also includes a third optical system arranged adjacent said beam splitter imagewise thereof, an aperture stop, and a fourth optical system having positive refractive power. The third and fourth optical systems include a plurality of lens elements preferably comprising of at least two glass types for facilitating the correction of aberrations. The system is designed such that the beam splitter is of a practical size, while allowing for a suitable working distance on the image side, a large numerical aperture, and sub-quarter micron resolution in the ultraviolet wavelength range.

Abstract: A system for multiple mode imaging is disclosed herein. The system is a catadioptric system preferably having an NA greater than 0.9, highly corrected for low and high order monochromatic aberrations. This system uses unique illumination entrances and can collect reflected, diffracted, and scattered light over a range of angles. The system includes a catadioptric group, focusing optics group, and tube lens group. The catadioptric group includes a focusing mirror and a refractive lens/mirror element. The focusing optics group is proximate to an intermediate image, and corrects for aberrations from the catadioptric group, especially high order spherical aberration and coma. The tube lens group forms the magnified image. Different tube lens groups can be used to obtain different magnifications, such as a varifocal tube lens group to continuously change magnifications from 20 to 200.times.. Multiple imaging modes are possible by varying the illumination geometry and apertures at the pupil plane.

Abstract: In a projection printing apparatus, illumination light from a lamp housing illuminates a photomask, and a diffracted light beam from the photomask is focused on an exposed substrate via a projection optical system to project a circuit pattern, the projection optical system including first and second halfmirrors and first and second concave mirrors. The first and second halfmirrors are arranged in symmetry or similar symmetry with respect to a normal to an optical axis of a diffracted light beam directed from the first halfmirror to the second halfmirror. Thus, a projection printing apparatus and a projection printing method are obtained in which unevenness in transmissivity in the projection optical system can be compensated for and steric hindrance or degradation of image characteristics is not caused.

Abstract: A method for precise design of light distribution for lighting equipment that use light-emitting devices, and for subsequently producing such equipment. By modeling the internal structure of an LED device with respect to the geometry and characteristics of a chip portion, chip reflector and lens portion, illuminating light from an LED device is classified into direct light from the chip portion and the reflected light from the chip reflector. The unknown values necessary for the modeling are specified preliminarily by actual measurements. Subsequently, the original geometry of the lens step is determined roughly based on the target direction and the diffusion angle of the light transmitted through the step. The manner in which the direct light from the chip portion and the reflected light from the chip reflector are transmitted through the lens portion and the lens step is simulated by ray tracing.

Abstract: To use a beam splitting optical system smaller than the conventional beam splitters and to set a longer optical path between a concave, reflective mirror and an image plane. A light beam from an object surface travels through a first converging group to enter a beam splitter, and a light beam reflected by the beam splitter is reflected by a concave, reflective mirror to form an image of patterns on the object surface inside the concave, reflective mirror. A light beam from the image of the patterns passes through the beam splitter and thereafter forms an image of the patterns through a third converging group on an image plane.

Abstract: A projection-type display apparatus including an elliptical condenser mirror having a concave reflecting surface consisting of part of a substantially elliptical surface, a light source arranged near a first focal point of the elliptical surface, a collimator lens having a focal point near a second focal point of the elliptical surface, and an optical modulation element array having a lens array on the collimator lens side, in which optical modulation elements each having an area S are two-dimensionally arranged.

Abstract: The present invention relates to a reflecting optical system, wherein the reflecting optical system comprises a first reflecting surface having a positive power and a second reflecting surface having a negative power, wherein at least one of the surfaces is inclined and the reflecting optical system comprises a substantially afocal optical system of the surfaces.

Abstract: In a catadioptric optical system, the first focusing lens system A includes a concave mirror Mc, and it forms an intermediate image of the first plane R. The second focusing lens system B includes an aperture stop AS, and it forms a refocused image of the intermediate image on the second plane W. A reflecting surface M.sub.P1 is placed so that the light flux leaving the first focusing lens system A is guided to the second focusing lens system B. There are one or more lens surfaces that satisfy the conditionh/.phi.<0.85 (1)and one or more lens surfaces that satisfy the condition0.85<h/.phi.<1.2 (2)where h is the height at each lens surface of the light beam that is assumed to be emitted from the intersection of the optical axis of the first plane and passes through the lens surfaces with the maximum numerical aperture, and .phi. is the radius of the diaphragm of the aperture stop.

Abstract: A structure and method for a collection system for a projector includes a collector for reflecting light and a correcting mechanism for receiving the reflected light. The collector and the correcting mechanism, in combination, correct the light and output a light beam having a uniform image size.

Abstract: A unitary, at least partially dielectric, element having formed thereon plural electromagnetic radiation reflecting surfaces, at least one of which is a total internal reflection surface.

Abstract: An ocular optical system suitable for a head- or face-mounted image display apparatus which is compact, lightweight and satisfactorily corrected for aberrations, and in which no intermediate image is formed. The image display apparatus includes an image display unit (9) and an optical system (10) for projecting a displayed image into an eyeball (7). The optical system (10) is arranged such that light rays which are emitted from the image display unit (9) and enter the eyeball (7) are reflected at least three times by surfaces (12, 13 and 14) having power in backward ray tracing.

Abstract: In a cata-dioptric optical system having a combination of a reflection system and a refraction system for reduction-projecting an object on a first plane onto a second plane, a polarization beam splitter and a quarter wavelength plate are provided to split the incident light and the reflected light. The light beam directed to the polarization beam splitter is converted to a substantially collimated light beam by a first group of lenses. A second group of lenses are arranged between the polarization beam splitter and a concave reflection mirror to diverge the light beam. The light reflected by the concave reflection mirror is directed back to the polarization beam splitter with a substantially collimated state by the second group of lenses. The light beam from the second group of lenses transmitted through the polarization beam splitter is focused by a third group of lenses having a positive refraction power to form a reduced image.