Abstract: An optical imaging system includes a first lens, a second lens, a third lens, a fourth lens, and a fifth lens, disposed in order from an object side, and a first reflection member and a second reflection member, disposed on an object side of the first lens, each having a freeform surface.

Abstract: An optical imaging system includes a first lens having refractive power, a second lens including a first reflective region formed on an object-side surface of the second lens, a third lens having a second reflective region formed on an image-side surface of the third lens, and a fourth lens having refractive power.

Abstract: Provided is a camera lens of a catadioptric optical system consisting of two lens assemblies and one lens and having a small height, a narrow angle, and good optical properties. The camera lens includes: a first lens assembly including an object side surface having a first refractive surface and a second reflective surface in a peripheral region and a central region thereof, and an image side surface having a second refractive surface, a fifth refractive surface and a sixth refractive surface that are sequentially arranged from a peripheral region to a central region thereof; a second lens assembly including an object side surface having a third refractive surface and a fourth refractive surface that are sequentially arranged from a peripheral region to a central region, and an image side surface having a first reflective surface; and a third lens having a refractive power.

Abstract: A catadioptric system (LS) is provided with: a first reflecting mirror (M1) that reflects light from an object; a second reflecting mirror (M2) that reflects light reflected by the first reflecting mirror (M1); a first lens group (G1) that transmits light reflected by the first reflecting mirror (41) and travelling toward the second reflecting mirror (M2), and transmits light reflected by the second reflecting mirror (M2); and a second lens group (G2) that transmits light reflected by the second reflecting mirror (M2) and transmitted through the first lens group (G1). The catadioptric system is configured that an image of the object is formed by light transmitted through the second lens group (G2).

Abstract: A catadioptric telescope is a modified version of a conventional Maksutov-Cassegrain optical telescope. In accordance with the invention, the reflecting surfaces of the primary mirror and the secondary spot mirror are on the second surfaces of the primary mirror and correcting lens, respectively. In further accordance with the invention, two of these telescopes can be joined together to form a binocular telescope array. The array can be easily customized to suit different remote sensing/satellite applications.

Abstract: A projection display apparatus includes a light source module, an optical engine module and a projection lens module. The optical engine module includes a prism and a light valve. The projection lens module includes a first lens group and a second lens group. The first lens group is disposed between the screen end and the imaging end. The first lens group includes a first lens, a second lens and a third lens, which are sequentially disposed from the screen end to the imaging end and have negative, negative and positive refractive powers, respectively. The second lens group is disposed between the first lens group and the imaging end and has a positive refractive power. The second lens group includes a fourth lens, a fifth lens and a sixth lens, which are sequentially disposed from the screen end to the imaging end and have negative, positive and positive refractive powers, respectively.

Abstract: A projector includes an image beam generator and a projecting lens. The projecting lens includes a relay system and a projection system. The relay system has a focusing set and a converging set, and the projection system has a projection lens group and a reflector. The image beam generator generates an image beam, and emits it to the projecting lens, and the image beam emits through the focusing set, the converging set, and the projection lens group in sequence, and then is reflected by the reflector to enter the projection lens group again. After leaving the projection lens group the image beam emits through a lens of the converging set, and then is projected onto a screen.

Abstract: In an embodiment, a method of aligning elements in a manufacturing process includes placing a middle element onto a base element, the base element forming first alignment features, the middle element forming apertures therethrough corresponding to the first alignment features. The method also includes placing second alignment features of an upper element onto the first alignment features such that the first and second alignment features cooperate, through the apertures, to align the upper element with the base element. An infrared lens assembly includes a lens formed of an infrared transmitting material that is disposed within a carrier of a base material, the lens being molded within the carrier with at least one feature that secures the lens to the carrier.

Abstract: A projector includes an image ray generator and a projecting lens, wherein the image ray generator generates image rays. The projecting lens includes a relay optical system for receiving the image rays and a projection optical system having at least one lens and a reflector. Whereby, the image rays pass through the relay optical system, pass through the at least one lens, and then are reflected by the reflector. After being reflected, the image rays pass through the at least one lens again, and then leave the projecting lens to be projected onto a screen. In addition, the invention further discloses the structure of the projecting lens and a method of projecting images.

Abstract: A reflective type telephoto lens and a photographing apparatus including the reflective type telephoto lens are provided. The reflective type telephoto lens includes: a first lens that receives an incident flux of light from an object side; a main mirror including a reflective unit that reflects light transmitted through the first lens toward the object side, and a transmission portion disposed on a center portion thereof; a sub-mirror group including a sub-mirror that reflects light from the main mirror toward an image side; and a focusing lens group that focuses the light reflected by the sub-mirror.

Abstract: An integrated illumination reference source for generating an illumination reference signal may include an optical element having a first outer surface and a second outer surface, such that the first and the second outer surface are substantially opposing. The optical element receives an incident optical signal at the first outer surface and projects the incident optical signal from the second outer surface onto a surface. A reflective device that is located on a region of the second outer surface is offset from an optical axis of the optical element. The reflective device includes a reflective surface that reflects a portion of the incident optical signal from the second outer surface back through the first outer surface, whereby the reflective surface of the reflective device is encapsulated between the first outer surface and the second outer surface of the optical element.

Abstract: A system and method is described for correcting aberrations caused by field curvature with a catadioptric objective. In one example, a catadioptric optical system includes a first catadioptric element and a second catadioptric element. The first catadioptric element includes a first surface positioned to reflect a beam and a second surface positioned to focus the beam reflected by the first surface. The second catadioptric element is configured to receive the beam reflected by the second surface of the first catadioptric element. The second catadioptric element includes a third surface positioned to reflect the beam, and a fourth reflective surface positioned to focus the beam reflected by the third reflective surface. A curvature of the third or fourth surfaces of the second catadioptric element is chosen to apply a positive contribution to a field curvature associated with the first catadioptric element.

Abstract: Systems and methods are provided for a solid filled mirrored lens system capable of wider fields of view and wider spectra than current lens systems. The mirrored lens is used to focus light incident upon a right circular cylindrical central body comprising a substantially planar first surface and a substantially planar second surface. A primary reflecting surface is located on the second surface of the central body and shaped as an annulus with a void in the central region of the second surface. Further, a secondary reflecting surface is located in a central region of the first surface facing the primary reflecting surface.

Abstract: A catadioptric lens system includes, in order of light travel: a first lens group that includes a concave mirror and a convex mirror and has a positive refractive power; a second lens group that is positioned on the image side of the concave mirror and has a negative refractive power; and a third lens group that has a positive refractive power, wherein the first lens group has a plurality of lenses on the image side of the concave mirror, and some lenses of the plurality of lenses are formed as a vibration-proof group so as to be movable in a direction perpendicular to an optical axis.

Abstract: A catadioptric lens system includes, in order of light travel: a first lens group that includes a concave mirror and a convex mirror and has a positive refractive power; a second lens group that is positioned on the image side of the concave mirror and has a negative refractive power; and a third lens group that has a positive refractive power, wherein a close-range object is brought into focus by moving the second lens group in a direction parallel with the optical axis, and wherein the following conditional expression is satisfied 0<f/f12??(0) where f is a focal length of the whole system in a state where the focus is at infinity, and f12 is a composite focal length of the first lens group and the second lens group in a state where the focus is at infinity.

Abstract: A semiconductor laser driver includes a light detection circuit to detect a quantity of light as a detected light emission intensity and output the detected light emission intensity to the control circuit, and a control circuit to control a light emission intensity for the semiconductor laser based on the detected light emission intensity and on a predetermined light emission intensity setting value. The light detection circuit includes a photoelectric conversion element to convert the quantity of light emitted from the semiconductor laser into an electrical current and output the converted electrical current, a current magnification setting circuit to amplify the electrical current output from the photoelectric conversion element to a predetermined amplified current at one of multiple different predetermined magnifications, a detection resistor to convert the amplified current output from the current magnification setting circuit into a voltage and output the voltage as the detected light emission intensity.

Abstract: An RF/Optical shared aperture is capable of transmitting and receiving optical signals and RF signals simultaneously. This technology enables compact wide bandwidth communications systems with 100% availability in clear air turbulence, rain and fog. The functions of an optical telescope and an RF reflector antenna are combined into a single compact package by installing an RF feed at either of the focal points of a modified Gregorian telescope.

Abstract: An optical scanner, scanner apparatus, or scanner assembly, which may be particularly advantageous for use in a multiphoton microscope, includes a first drivable bending component, a second drivable bending component mounted perpendicularly to the first component, and at least one optical waveguide coupled one or both of the first and second bending components, wherein the at least one optical waveguide provides both a propagation path for a multiphoton excitation radiation delivery between a light source and a target and a multiphoton-induced emission radiation delivery between the target and a detector. A GRIN relay lens. A multiphoton microscope incorporating the scanner and the GRIN relay lens.

Abstract: A catadioptric lens system includes: a first lens group including a concave mirror and a convex mirror and having positive refractive power; a second lens group having positive refractive power; and a third lens group having negative refractive power, the first to third lens groups being provided, in order, on a light path of incident light and in a direction of travel of the incident light.

Abstract: Ring-field, catoptric and catadioptric, unit-magnification, projection optical systems having non-concentric optical surfaces are disclosed. Each system has a system axis with object and image planes on opposite sides of the system axis. The non-concentric surfaces allow for working distances of the object and image planes in excess of 100 millimeters to be achieved, with a ring-field width sufficient to allow a rectangular object-field having a long dimension in excess of 100 mm to be projected.

Abstract: A catadioptric optical system includes, in order from an object side to an image side and arranged along an optical axis, a first catadioptric unit, a second catadioptric unit disposed in axial alignment with the first catadioptric unit and with a space therebetween; and a lens group disposed in axial alignment with the first and second catadioptric optical units. Light rays arriving from an object plane undergo a first reflection at the image-side surface of the first catadioptric optical unit, a second reflection at the object-side surface of the first catadioptric optical unit, a third reflection at the image-side surface of the second catadioptric optical unit, and a fourth reflection at the object-side surface of the second catadioptric optical unit. Advantageously, the sum the outward Petzval curvatures is cancelled out by the sum of inward Petzval curvatures.

Abstract: Embodiments of the invention include an optical system and an optical system module, coupled to a distal end of a fluorescence emission endoscope apparatus, an optical waveguide-based fluorescence emission endoscopy system, and a method for remotely-controlled, multi-magnification imaging of a target or fluorescence emission collection from a target with a fluorescence emission endoscope apparatus. An exemplary system includes an objective lens disposed in a distal end of an endoscope apparatus. The lens is adapted to transmit both a visible target illumination and a fluorescence-emission-inducing target illumination as well as fluorescence-emission and visible light from the target. The system can thus simultaneously provide low magnification, large field of view imaging and high magnification, high-resolution multiphoton imaging with a single lens system.

Abstract: An afocal beam relay has first and second primary concave reflective surfaces and first and second secondary convex toroidal reflective surfaces. The centers of curvature of each of the first and second primary reflective surfaces and first and second secondary reflective surfaces lie on an axis. The first and second secondary convex reflective surfaces face toward the first and second primary concave reflective surfaces and are disposed to relay a decentered entrance pupil to a decentered exit pupil. An aspheric corrector element is disposed in the path of an input beam of light that is directed by the primary and secondary surfaces to the decentered entrance pupil. The directed beam of light between the first and second secondary convex mirrors is collimated in one direction and focused in mid air in an orthogonal direction.

Abstract: Provided is a panoramic imaging lens including a first lens piece and a second lens piece. The panoramic imaging lens realizes reduced complexity and cost of manufacturing, and stray rays causing flare or ghost phenomenon are suppressed by cutting a side of the second lens piece, thereby improving image quality.

Abstract: A catadioptric lens system includes, in order of light travel: a first lens group that includes a concave mirror and a convex mirror and has a positive refractive power; a second lens group that is positioned on the image side of the concave mirror and has a negative refractive power; and a third lens group that has a positive refractive power, wherein the first lens group has a plurality of lenses on the image side of the concave mirror, and some lenses of the plurality of lenses are formed as a vibration-proof group so as to be movable in a direction perpendicular to an optical axis.

Abstract: A catadioptric lens system includes, in order of light travel: a first lens group that includes a concave mirror and a convex mirror and has a positive refractive power; a second lens group that is positioned on the image side of the concave mirror and has a negative refractive power; and a third lens group that has a positive refractive power, wherein a close-range object is brought into focus by moving the second lens group in a direction parallel with the optical axis, and wherein the following conditional expression is satisfied 0<f/f12??(0) where f is a focal length of the whole system in a state where the focus is at infinity, and f12 is a composite focal length of the first lens group and the second lens group in a state where the focus is at infinity.

Abstract: A 360 degree viewing angle lens unit, from the object side to the image side thereof, includes a 360 degree viewing angle lens and a relay lens. The viewing angle lens includes an annular incident surface, a first reflective surface, a second reflective surface, and an emitting surface. The annular incident surface has a positive radius of curvature and symmetrically concentric around an optical axis of the lens unit. The first reflective surface has a positive radius of curvature and is symmetrically concentric around the optical axis. The second reflective surface has a negative radius of curvature, and is coaxial with the incident surface. The emitting surface has a positive radius of curvature and is coaxial with the first reflective surface. The relay lens has a positive refractive power and is aligned with the emitting surface. The relay lens is configured for condensing image light output from the emitting surface.

Abstract: Ring-field, catoptric and catadioptric, unit-magnification, projection optical systems having non-concentric optical surfaces are disclosed. Each system has a system axis with object and image planes on opposite sides of the system axis. The non-concentric surfaces allow for working distances of the object and image planes in excess of 100 millimeters to be achieved, with a ring-field width sufficient to allow a rectangular object-field having a long dimension in excess of 100 mm to be projected.

Abstract: An optical element that is made of a transparent medium L1 rotationally symmetric relative to the central axis 2 with a refractive index greater than 1, wherein the transparent medium L1 has a first transmissive surface 11, a first reflective surface 12, a second reflective surface 13 arranged at an opposite side to the image plane 5 relative to the first reflective surface 12 and a second transmissive surface 14 arranged at the image plane 5 side relative to the second reflective surface 13 and that the flux of light entering the transparent medium L1 goes into it by way of the first transmissive surface 11 so as to be reflected to the opposite side to the image plane 5 by the first reflective surface 12 and then to the image plane 5 side by the second reflective surface 13 to form an optical path before going out from the transparent medium L1 at the image plane 5 side by way of the second transmissive surface 14 in the order of forward ray tracing.

Abstract: An afocal beam relay has a concave reflective surface having a first center of curvature and a first vertex that define an optical axis. A convex reflective surface has a second center of curvature that is substantially coincident with the first center of curvature and a second vertex that lies along the optical axis. The convex reflective surface faces toward the concave reflective surface to relay a decentered entrance pupil to a decentered exit pupil. An aspheric corrector element is disposed in the path of input light that is directed to the decentered entrance pupil and has correction values that are substantially centered on the first center of curvature.

Abstract: An optical element is made of a transparent medium that is rotationally symmetric relative to the central axis with a refractive index greater than 1. The transparent medium has a first transmissive surface at the outermost periphery relative to the central axis, a first reflective surface at the side of the central axis relative to the first transmissive surface, a second reflective surface at the side opposite to the image plane relative to the first reflective surface and a second transmissive surface at the side of the image plane relative to the second reflective surface. The flux of light enters and proceeds through the transparent medium via the first transmissive surface, the first reflective surface, the second reflective surface and the second transmissive surface to form an optical path. The optical path is formed only at a side relative to the central axis.

Abstract: An imaging system including a back-plane reflector having a concave aspherical reflecting surface and an outer diameter that is no greater than a first distance, with an aperture formed in the back-plane reflector, the aperture for admitting light from a field of view to the imaging system, a fore-plane reflector having a concave aspherical reflecting surface and an outer diameter that is no greater than the first distance, with an aperture formed in the fore-plane reflector, the aperture for discharging the light from the imaging system to an image plane, and a central reflector having a convex aspherical reflecting surface for receiving light from the fore-plane reflector and discharging the light from the imaging system through the aperture in the fore-plane reflector.

Abstract: There is a need for providing a projection optical system that is appropriate for maintaining high resolution with low distortion, miniaturizing a reflector, decreasing the number of reflectors, and decreasing the depth and the bottom (or top) of a display used for a rear projection television, for example. The projection optical system according to the invention enlarges and projects images from a primary image surface existing at a reducing side to a secondary image surface existing at an enlarging side. The projection optical system has a first optical system L11 and a second optical system L12. The first optical system L11 forms an intermediate image (position II) of the primary image surface. The second optical system L12 has a concave reflector AM1 that forms the secondary image surface resulting from the intermediate image. A light beam travels from the center of the primary image surface and to the center of the secondary image surface and crosses an optical axis.

Abstract: An apparatus is disclosed including: an entrance aperture for admitting light from a source; an optical collector configured to receive light admitted through the entrance aperture and concentrate the light onto a receiver element; and an optical homogenizer element configured and arranged to image the entrance aperture onto the receiver element.

Abstract: A 360 degree viewing angle lens unit, from the object side to the image side thereof, includes a 360 degree viewing angle lens and a relay lens. The viewing angle lens includes an annular incident surface, a first reflective surface, a second reflective surface, and an emitting surface. The annular incident surface has a positive radius of curvature and symmetrically concentric around an optical axis of the lens unit. The first reflective surface has a positive radius of curvature and is symmetrically concentric around the optical axis. The second reflective surface has a negative radius of curvature, and is coaxial with the incident surface. The emitting surface has a positive radius of curvature and is coaxial with the first reflective surface. The relay lens has a positive refractive power and is aligned with the emitting surface. The relay lens is configured for condensing image light output from the emitting surface.

Abstract: In general, in a first aspect, the invention features a system that includes a microlithography projection optical system. The microlithography projection optical system includes a plurality of elements arranged so that during operation the plurality of elements image radiation at a wavelength ? from an object plane to an image plane. At least one of the elements is a reflective element that has a rotationally-asymmetric surface positioned in a path of the radiation. The rotationally-asymmetric surface deviates from a rotationally-symmetric reference surface by a distance of about ? or more at one or more locations of the rotationally-asymmetric surface.

Abstract: A projection optical system includes: a refracting optical section composed mainly of a plurality of lenses disposed in order from a reducing side, and having positive power; a first reflecting optical section having a concave reflecting optical surface; and a second reflecting optical section having a convex reflecting optical surface, wherein the projection optical system satisfies the following conditional expression, denoting a focal length of a total system combining the refracting optical section, the first reflecting optical section, and the second reflecting optical section as F, and a focal length of the refracting optical section as FL: 0.2<F/FL<0.5??(1).

Abstract: The present invention is a combination non-imaging concentrator in which at least one surface or volume is incorporated as an optical element to increase obliquity of reflection at walls of a light guide. The combination non-imaging concentrator may be used in a solar energy system to receive solar radiation from optical components and then output the solar radiation to a photovoltaic cell for conversion to electricity. One or more lenses may be formed integrally with the light guide, or may be used in conjunction with the light guide as separate components.

Abstract: A projection optical system satisfies a conditional formula: 0.01<{(tan ?f1?tan ?f2)?(tan ?n1?tan ?n2)}·(?2/?1)<0.

Abstract: An optical system is adapted to form an image having a full 360° angle of view on an image plane. The optical system includes a front unit having at least two reflecting surfaces, each rotationally symmetric about a center axis, and a rear unit that is rotationally symmetric about the center axis and has positive power. The first reflecting surface is located opposite to an entrance pupil, and the second reflecting surface is located on the same side as the first reflecting surface. The entrance pupil in a section including the center axis is located between the outer periphery of the first reflecting surface and the outer periphery of the second reflecting surface. A light beam coming from afar passes through the front unit and the rear unit in order, forming an image at a position of an image plane off the center axis.

Abstract: A projection optical system includes: a refracting optical section composed mainly of a plurality of lenses disposed in order from a reducing side, and having positive power; a first reflecting optical section having a concave reflecting optical surface; and a second reflecting optical section having a convex reflecting optical surface, wherein the projection optical system satisfies the following conditional expression, denoting a focal length of a total system combining the refracting optical section, the first reflecting optical section, and the second reflecting optical section as F, and a focal length of the refracting optical section as FL: 0.2<F/FL<0.5??(1).

Abstract: A projection optical system includes: a refracting optical section composed mainly of a plurality of lenses disposed in order from a reducing side, and having positive power; a first reflecting optical section having a concave reflecting optical surface; and a second reflecting optical section having a convex reflecting optical surface, wherein the projection optical system satisfies the following conditional expression, denoting a focal length of a total system combining the refracting optical section, the first reflecting optical section, and the second reflecting optical section as F, and a focal length of the refracting optical section as FL: 0.2<F/FL<0.5??(1).

Abstract: In a projection optical system for use in an image projection apparatus illuminating an image display panel forming an image in accordance with a modulating signal with illumination light from a light source, the projection optical system includes first and second optical systems arranged along an optical path defining an upstream-downstream direction in the order described from upstream to downstream on the downstream side of the image display panel. The first optical system includes at least one dioptric system and has positive power. The second optical system includes at least one reflecting surface having power and has positive power. The image formed by the image display panel is formed as an intermediate image in the optical path, and the intermediate image is magnified and projected.

Abstract: A variety of lenses, lens assemblies, imaging devices, applications for such lenses, assemblies and devices, and related methods of operation and manufacturing are disclosed. At least some embodiments of the invention relate to a lens that includes first and second inward-facing surfaces that are each at least partly reflective. The lens further includes a first aperture that is positioned around at least a portion of an outer periphery of one of the first and second inward-facing surfaces, and a second aperture existing proximate a central region of the lens. The light proceeding within the lens between the first and second inward-facing surfaces is reflected at least twice on at least one of the first and second inward-facing surfaces as it travels between the first aperture and the second aperture.

Abstract: A projection optical system includes: a refracting optical section composed mainly of a plurality of lenses disposed in order from a reducing side, and having positive power; a first reflecting optical section having a concave reflecting optical surface; and a second reflecting optical section having a convex reflecting optical surface, wherein the projection optical system satisfies the following conditional expression, denoting a focal length of a total system combining the refracting optical section, the first reflecting optical section, and the second reflecting optical section as F, and a focal length of the refracting optical section as FL: 0.2<F/FL<0.5??(1).

Abstract: In general, in a first aspect, the invention features a system that includes a microlithography projection optical system. The microlithography projection optical system includes a plurality of elements arranged so that during operation the plurality of elements image radiation at a wavelength ? from an object plane to an image plane. At least one of the elements is a reflective element that has a rotationally-asymmetric surface positioned in a path of the radiation. The rotationally-asymmetric surface deviates from a rotationally-symmetric reference surface by a distance of about ? or more at one or more locations of the rotationally-asymmetric surface.

Abstract: A compact, optically fast catadioptric imager. In one embodiment, the catadioptric imager of this invention includes a first group of optical elements optically disposed to receive electromagnetic radiation from an object and having positive optical power, a second group of optical elements, optically disposed between the first group of optical elements and an image plane, having at least one optical surface and having positive optical power, a third group of optical elements, optically disposed between the object and the second group of optical elements, having at least one optical surface and having negative optical power, a fourth group of optical elements substantially centered along an optical axis of said second group of optical elements and having negative optical power, and a fifth group of optical elements having positive optical power.

Abstract: A catadioptric objective includes a plurality of optical elements arranged along an optical axis to image a pattern from an object field in an object surface of the objective to an image field in an image surface region of the objective at an image-side numerical aperture NA with electromagnetic radiation from a wavelength band around a central wavelength ?. The optical elements include a concave mirror and a plurality of lenses. The projection objective forms an image of the pattern in a respective Petzval surface for each wavelength ? of a wavelength band, the Petzval surfaces deviating from each other for different wavelengths. In embodiments, a longitudinal departure p of the Petzval surface at a given wavelength from a planar reference surface at an edge field point of the image field (at maximum image height y?), measured parallel to the optical axis in the image surface region, varies with the wavelength ? according to dp/d?<(0.2?/NA2)/nm.

Abstract: An aspheric reduction objective has a catadioptric partial objective (L1), an intermediate image (IMI) and a refractive partial objective (L2). The catadioptric partial objective has an assembly centered to the optical axis and this assembly includes two mutually facing concave mirrors (M1, M2). The cutouts in the mirrors (B1, B2) lead to an aperture obscuration which can be held to be very small by utilizing lenses close to the mirrors and having a high negative refractive power and aspheric lens surfaces (27, 33). The position of the entry and exit pupils can be corrected with aspherical lens surfaces (12, 48, 53) in the field lens groups. The number of spherical lenses in the refractive partial objective can be reduced with aspherical lens surfaces (66, 78) arranged symmetrically to the diaphragm plane. Neighboring aspheric lens surfaces (172, 173) form additional correction possibilities.

Abstract: In a projection optical system for use in an image projection apparatus illuminating an image display panel forming an image in accordance with a modulating signal with illumination light from a light source, the projection optical system includes first and second optical systems arranged along an optical path defining an upstream-downstream direction in the order described from upstream to downstream on the downstream side of the image display panel. The first optical system includes at least one dioptric system and has positive power. The second optical system includes at least one reflecting surface having power and has positive power. The image formed by the image display panel is formed as an intermediate image in the optical path, and the intermediate image is magnified and projected.