Abstract: A compatible optical pickup for recording and/or reproducing information on/from multiple kinds of optical discs having different thicknesses by selectively using source lights of respective different wavelengths corresponding to a kind of disc and using a common objective lens. At least one phase compensator, which compensates a phase of a light having a particular wavelength to correct for spherical aberration due to a thickness difference between the kinds of optical discs and/or chromatic aberration due to a wavelength difference between the required source lights, is positioned between the source lights and an entrance pupil of the objective lens. Each phase compensator compensates light of at least one wavelength and passes light of at least one other wavelength without significant relative phase alteration. By using two phase compensators, the optical pickup may be made compatible with at least three kinds of optical discs.

Abstract: An optical imaging apparatus includes an optical probe and an apparatus main body which controls and drives the optical probe via a connecting cable. The optical probe includes a low-coherence light source, a half mirror (light separating means), an XY reflecting mirror scan (horizontal scanning means), an objective optical system, a reflecting mirror, a modulating mirror (reference light reflecting means), and a photo detector (optical detecting means). In the optical probe, the modulating mirror and the objective optical system, as optical path length interlockingly adjusting means, are integrally arranged to an optical path length interlockingly adjusting base, together with a reflecting-side lens. The optical probe has an advancing and regressing driving unit which advances and regresses the optical path length interlockingly adjusting base in the optical axis direction (Z direction).

Abstract: A display device for use in a vehicle is provided, by which an image for superposition displayed on a display source is projected on a windshield of a vehicle so that the foreground of the vehicle and a virtual image of the image for superposition are accurately seen together even when a seat position and a physique of a driver change and when a shape of the windshield changes. A light of inverse image for superposition displayed on a display surface 5a of a display unit 5 in a dashboard 1 in a vehicle is projected on a windshield 3 so that the driver sees the foreground visible through the windshield 3 together with a virtual image of the inverse image for superposition reflected on the windshield 3 in front of an eye point I, that is, a virtual image of the original image for superposition.

Abstract: A projection exposure apparatus comprises a projection optical system for projecting a pattern of a mask on a photosensitive substrate; a plane-parallel plate disposed on a side of the photosensitive substrate of the projection optical system, almost perpendicularly to an optical axis of the projection optical system; and a adjustment device for adjusting at least one of an inclination angle of a normal line of the plane-parallel plate relative to the optical axis of the projection optical system and an inclination angle of the plane-parallel plate.

Abstract: A color-separating prism for producing narrow-spectral light from broader spectral light includes first, second, and third component prisms that form first and second adjacent pairs of faces. The color-separating prism also includes first and second reflective layers disposed between the prisms. The first and second reflective layers each reflect separate portions of input light back toward the front surface. In operation, a first portion of a light beam in a first wavelength range is reflected from the first reflective layer back toward the front face of the prism, and a second portion of the light beam in a second wavelength range is reflected from the second reflective layer back toward the front face of the prism. The first and second portions are totally internally reflected from the front face and exit the color-separating prism. The color-separating prism can be used in display systems.

Abstract: An observation optical system or a photographing optical system comprises, between a pupil surface and an image surface, a first prism 3 and a second prism. The first prism 3 includes a 1st-1st surface 31 which has both of actions of transmitting and reflecting light in the path, a 1st-2nd surface 32 which has both of actions of reflecting and transmitting the light in the path, and a 1st-3rd surface 33 which transmits the light in the path. The second prism 4 includes a 2nd-1st surface 41 which is disposed adjacent to the 1st-2nd surface 32 at an air space away and which transmits the light in the path at least twice and a 2nd-2nd surface 42 which reflects the light in the path. The 1st-1st surface 31 is constructed of a prism face to which a volume hologram 6 is applied.

Abstract: A real image mode finder optical system includes an objective optical system with a positive refracting power, an image erecting optical system having a plurality of reflecting sections for erecting an image formed by the objective optical system, and an ocular optical system for introducing an erected image into an observer's eye. At least one lens of the objective optical system or the ocular optical system is configured to be rotational asymmetrical with respect to the optical axis, and a light-blocking member for blocking reflected light at the end face of the lens is provided adjacent to the lens or spaced away therefrom through air.

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. Rays incident on the surface C and rays reflected from the surface B intersect each other in the prism.

Abstract: An image display apparatus allows an image from a single image display device to be led to two eyes without using a half-mirror, thereby allowing observation of a bright image, and facilitates correction of various aberrations. A viewing optical system includes a left ocular part, a right ocular part, and an optical path distributing part for leading a light beam from a single image display device to the left and right ocular parts. The left and right ocular parts each have at least two reflecting surfaces. The optical path distributing part has at least one pair of reflecting surfaces for left and right optical paths. These reflecting surfaces are formed from rotationally asymmetric curved reflecting surfaces having the function of correcting decentration aberrations.

Abstract: An optical device for receiving input light and for acting on the input light to produce output light includes a first reflector and a second reflector supported in a spaced-apart, confronting relationship with the first reflector such that the input light received by the optical device, at least potentially, undergoes multiple reflections between the first and second reflectors. At least a selected one of the first and second reflectors is configured to subject each one of a plurality of different portions of the input light to one of a plurality of different reflectance values to produce an emitted light passing through at least the selected reflector in a way which is combinable to generate the output light.

Abstract: A modularized light-guiding apparatus and manufacturing method, which may make the light of a light source proceed at least twice light reflections of predetermined directions. The light-guiding apparatus includes a plurality of modularized reflection elements, which may be differentiated to several different types of reflection element. Each type of each reflection element all has substantially same adjoining device and edge size for providing to be adjoined and piled-up with another reflection element. But, the reflection element of different type individually has different number of reflection plane for providing the light to proceed different times of light reflection. It may determined the light reflection times and light-path length for the light-guiding apparatus, by choosing several different types of reflection element among plural reflection elements to proceed the piling-up for the light-guiding apparatus.

Abstract: An image display apparatus has a light source, a reflective display device, an illumination optical system for guiding light from the light source to the display device to illuminate the display device, and a display optical system for guiding the light reflected by the display device to the pupil of an observer to allow the observer to observe an image displayed on the display panel. The illumination optical system and the display optical system have an optical element shared in part or are arranged so as not to interfere with each other, thereby providing the image display apparatus of compact structure. Particularly, where the display optical system is a thin optical system having a plurality of decentered, reflecting, curved surfaces, the appropriate illumination optical system is arranged, thereby providing the thin image display apparatus using the reflective display device.

Abstract: Disclosed are systems for, and methods of forming and applying 40 micron or greater diameter, substantially radially homogeneous, relatively high, (eg. 30-60 or greater J/cm 2), energy density, preferably 200-380 nm UV wavelength, (typically Nd-YAG Iraser produced 213 nm or 266 nm wavelength), electromagnetic radiation laser pulse(s), or equivalent in a continuous wave, to uniformly substantially purely optically ablate material from sample systems; coupled with analysis thereof in (ICP-OES), (ICP-MS), (MIP-OES), (MIP-MS) or other plasma based analysis systems, with relative freedom from calibration errors arising from element fractionation.

Abstract: PRS0847A foveated imaging system using a relatively simple optical imaging system with a reflective spatial light modulator at or near a pupil plane to correct off-axis aberrations. Maximum resolution is obtained for a single fixation point (foveal region) within the field of view at a time. The fixation point can be changed manually, by a predetermined scan pattern, or automatically varied for surveillance or tracking applications. A pre-calibrated look up table is used to vary the reflective spatial light modulator for each fixation point.

Abstract: The present invention relates to an 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 and facilitating correction of various aberrations. A viewing optical system includes a left ocular part 10L, a right ocular part 10R, and an optical path distributing part 20 for leading a light beam from a single image display device 3 to the left and right ocular parts 10L and 10R. The left and right ocular parts each have at least two reflecting surfaces 12R(L) and 13R(L). The planes of decentered optical paths of the axial principal rays in the left and right ocular parts are arranged to be approximately parallel to each other.

Abstract: A compact, bright and high-performance viewing optical system capable of color display has a reflection type image display device, an ocular optical system and an illuminating device formed from a plurality of juxtaposed illuminating light sources of different colors. An illuminating light guide optical device is placed between the entrance pupil and the reflection type image display device. The ocular optical system includes a decentered prism formed from a medium surrounded by three optical surfaces and having a refractive index larger than 1. A chromatic aberration producing device is placed between the entrance pupil and the illuminating light guide optical device. The chromatic aberration producing device is arranged to superimpose the images of the plurality of illuminating light sources on one another in the exit pupil.

Abstract: A lightweight, highly reliable optical pickup including a singlet objective lens is offered by correcting coma aberrations which adversely affect properties of the objective lens having an increased NA. A convergent optical system is composed of a singlet objective lens with a NA of 0.75 or more and includes an aberration-correcting optical system which corrects coma aberrations due to an inclination or shift of central axes of both surfaces of the objective lens or an inclination of the objective lens or the optical storage medium to an optical axis of the optical pickup.

Abstract: An optical pickup apparatus, in which the quantity of light incident to an aperture diaphragm of an objective lens and a “rim intensity (RI)” are maintained constant even when a spherical aberration is corrected by passing a light beam through an expander lens unit before it reaches the objective lens, and which is able to adequately read/write information signals from/to optical recording media, and a read/write apparatus which includes the optical pickup apparatus are provided. The expander lens unit includes a first lens group and a second lens group, and is disposed such that a focal position of the second lens group, which is closer to an objective lens than the first lens group, is on the aperture diaphragm of the objective lens.

Abstract: An optical path splitting element for splitting a light beam from a single object into two optical paths (left and right) is made compact in size and given a power to reduce the number of components thereof. An image display apparatus uses the optical path splitting element. The left and right optical paths are not in plane symmetry with each other but in 180-degree rotational symmetry with respect to only a straight line passing through the center of the object. When a pair of reflecting surfaces (left and right) closest to the object side are defined as first reflecting surfaces and a pair of reflecting surfaces (left and right) closest to the exit side are defined as final reflecting surfaces, axial principal rays incident on the first reflecting surfaces and those exiting from the final reflecting surfaces are not coplanar with each other in either of the left and right optical paths.

Abstract: A foveated imaging system using a relatively simple optical imaging system with a spatial light modulator located at or near a pupil plane to correct aberrations. Maximum resolution is obtained for a limited region defined by a single fixation point (a foveal region) within the field of view. The fixation point can be changed manually, by using a predetermined scan pattern, or automatically varied for surveillance or tracking applications.

Abstract: A method of identifying a change in focus and a change in illumination from a best focus and a best dose at a region on a substrate corresponding to a point in the image field of a lithographic printing tool is disclosed. The method includes forming a feature having a first pitch and a feature having a second pitch at the region on the substrate, and identifying a linewidth of the features. The identified linewidths are then used to determine the change in focus from the best focus and the change in dose from the best dose which would produce both the first pitch feature and the second pitch feature at the region.

Abstract: A projection display includes a light source for generating a beam output that contains first, second and third color components, a color separation/synthesizing prism unit having a color separation part for separating the beam output from the light source into the first, second and third color components that exit the prism unit in three different directions, and first, second and third light modulators for modulating the first, second and third color components that exit from the color separation part. The prism unit further has a color synthesizing part that receives the modulated first, second and third color components from the light modulators and that synthesizes the modulated first, second and third color components so as to form an output beam. A projection lens receives the output beam from the color synthesizing part, and is used to project a color image. The first, second and third color components have equal optical path lengths measured from the light source to the respective light modulator.

Abstract: A twin-lens projection display includes a dichroic synthesizing prism and an optical path compensating prism. First and second light modulators, which are disposed adjacent to first and second input sides of the dichroic synthesizing prism, provide modulated first and second color components to the same. A third light modulator is disposed adjacent to an input side of the optical path compensating prism, and provides a modulated third color component thereto. A first projection lens receives the first and second color components from an output side of the dichroic synthesizing prism, whereas a second projector lens receives the third color component from an output side of the optical path compensating prism.

Abstract: An optical pickup device includes a light source for generating light, a light path changing means for changing the traveling path of incident light, an objective lens for focusing incident light to form a light spot on a recording medium and having an incidence region of a predetermined size, a tracking mirror disposed on the light path between the light path changing means and the objective lens, for reflecting incident light emitted from the light source so that the light spot traces proper track positions of the recording medium, a lens unit consisting of at least two lenses which allow the light reflected from the tracking mirror to be incident on the incidence region of the objective lens, and a photo detecting unit for receiving light reflected from the recording medium and having passed through the objective lens and the light path changing means.

Abstract: A compact, bright and high-performance viewing optical system and an image display apparatus using the same. The viewing optical system uses an ocular optical system, which is formed from a decentered prism, and a reflection type image display device. The image display device has a light source and an illuminating light guide prism for guiding a light beam from the light source so that the light beam is applied to the display surface from the front side thereof. The ocular optical system includes a prism having an entrance surface through which a light beam reflected from the display surface enters the prism after passing through the illuminating light guide prism. The prism further has a reflecting surface and an exit surface through which the light beam exits from the prism.

Abstract: An optical device for a system presenting collimated images using a spherical mirror. The optical device makes it possible to present the user with an image corrected of off-centring distortion of a second kind due to an off-axis spherical mirror. In order to do this the optical device includes a tubular mirror whose optical characteristics ensure a high-quality image and correction of the off-centering distortion. The tubular mirror has a surface generated by the translation of a plane curve (a circular arc) along another plane curve (also a circular arc). The optical device is especially applicable to helmet sights for an aircraft pilot.

Abstract: An optical system includes a window, an optical corrector formed of a curved piece of a transparent material having a front surface and a back surface, and a sensor system with a sensor positioned such that the optical corrector is between the window and the sensor. At least one of the front surface and the back surface of the optical corrector is a segment of a convex aspheric curve rotated about a center, otherwise known as a torus.

Abstract: A red-reflecting film and a blue-reflecting film are formed in a substantially X shape on joint surfaces defined by the respective side faces of four columnar prisms or right-angle prisms. The red-reflecting film is continuously formed without separating at an intersection of the two reflecting films. The blue-reflecting film is, on the other hand, divided into two pieces by the red-reflecting film and an adhesive. It is preferable that that four columnar prisms are obtained from one block of sheet glass. This arrangement ensures an improvement in properties of a resulting light-selective prism.

Abstract: The present invention relates to a compact and high-performance prism optical system having, in order in which rays pass from the object side, a first transmitting surface (4), a first reflecting surface (5), a second reflecting surface (6), a third reflecting surface (7), a fourth reflecting surface (8), and a second transmitting surface (9). The first transmitting surface (4) and the second reflecting surface (6) are formed from the identical surface, and the second transmitting surface (9) and the third reflecting surface (7) are formed from the identical surface. The first reflecting surface (5) and the fourth reflecting surface (8) are formed from surfaces independent of the first transmitting surface (4) and the second transmitting surface (9). At least one of the reflecting surfaces is formed from a rotationally asymmetric surface. At least one of the second reflecting surface (6) and the third reflecting surface (7) has a power.

Abstract: An optical pickup device is provided with a focus error signal generating means which is adapted to calculate a first output sum signal obtained by adding together an output signal fed front one portion of the second light receiving means and an output signal fed from one portion of the third light receiving means, and to calculate a second output sum signal obtained by adding together an output signal fed from the other portion of the second light receiving leans and an output signal fed from the other portion of the third light receiving means, so as to calculate a difference between the first output sum signal and the second output sum signal, thereby producing a focus error signal.

Abstract: A high-performance and low-cost image-forming optical system having a minimal number of constituent optical elements and 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 first prism, a stop, and a second prism. The first prism has a first transmitting surface, a first reflecting surface, a second reflecting surface of positive power, and a second transmitting surface. The second prism has a first transmitting surface, a first reflecting surface, a second reflecting surface of positive power, and a second transmitting surface. The first transmitting surface and second reflecting surface of the first prism are the identical surface, and the first reflecting surface and second transmitting surface of the second prism are the identical surface. The image-forming optical system is approximately telecentric on the image side.

Abstract: An optical system includes an optical element having a plurality of reflective surfaces integrally formed, at least one reflective surface out of the plurality of reflective surfaces of the optical element being a curved surface a normal to which at an intersecting point with a reference axis does not coincide with the reference axis, an image pickup element to which light successively reflected by the plurality of reflective surfaces is incident, and an optical member for making at least part of the light that ought to enter the image pickup element, travel in an optical path different from an optical path toward the image pickup element. The light made to travel in the different optical path by the optical member is utilized for a purpose other than image pickup by said image pickup element.

Abstract: An aberration correcting apparatus and an optical pickup apparatus using this apparatus, in which a spherical aberration based on a thickness error of an optical disc substrate can be preferably eliminated and a thickness error permission range of the optical disc substrate can be widened even if an objective lens of a high numerical aperture is used.

Abstract: An optical system includes a curved window, an optical corrector adjacent to a curved inner surface of the window, an optical train positioned such that the optical corrector lies between the curved window and the optical train, a movable optical train support upon which the optical train is mounted, and a sensor disposed to receive an optical ray passing sequentially through the window, the optical corrector, and the optical train. The optical corrector has an inner surface and an outer surface, at least one of which has a shape described by a modified Zernike polynomial surface.

Abstract: A viewing optical system and image-forming optical system in which an intermediate image is formed once and two decentered prisms, i.e. first and second prisms, are arranged to correct each other's decentration aberrations, thereby attaining a wide viewing field angle and a short focal length. The second prism is placed closer to the object side than the first prism and has three optical surfaces, of which a first surface is an entrance surface also serving as a reflecting surface, a second surface is a reflecting surface, and a third surface is an exit surface. At least one of the first and second surfaces has a rotationally asymmetric surface configuration that gives a power to a light beam and corrects aberrations due to decentration. The first prism has a reflecting surface, an entrance surface, and an exit surface. The reflecting surface has a rotationally asymmetric surface configuration that gives a power to a light beam and corrects aberrations due to decentration.

Abstract: An optical system includes a curved window, an asymmetric, scoop-shaped optical corrector adjacent to a curved inner surface of the window, an optical train positioned such that the optical corrector lies between the curved window and the optical train, a movable optical train support upon which the optical train is mounted, and a sensor disposed to receive an optical ray passing sequentially through the window, the optical corrector, and the optical train. The optical corrector has an inner surface and an outer surface, at least one of which has a shape defined by an asymmetric polynomial.

Abstract: A virtually imaged phased array (VIPA) operating as a wavelength splitter to separate individual carriers from a wavelength division multiplexed (WDM) light. The VIPA has first and second surfaces. The second surface has a reflectivity which causes a portion of light incident thereon to be transmitted therethrough. The VIPA receives an input light at a respective wavelength within a continuous range of wavelengths. The first and second surfaces are positioned so that the input light is reflected a plurality of times between the first and second surfaces to cause a plurality of lights to be transmitted through the second surface. The plurality of transmitted lights interfere with each other to produce an output light which is spatially distinguishable from an output light produced for an input light having any other wavelength within the continuous range of wavelengths.

Abstract: An optical system having a first optical acting surface and a second optical acting surface in an optical path between a focal plane and a stop. In the optical path traced from the focal plane to the stop, light emitted from the focal plane is reflected by the second optical acting surface and thereafter reflected by the first optical acting surface to reach the stop. A ray connecting a center of the focal plane with a center of the stop via the first optical acting surface and the second optical acting surface is defined as a reference axis ray. The second optical acting surface is of a rotationally asymmetric, aspherical shape only one symmetry plane of which is a plane including the reference axis ray.

Abstract: The invention provides a prism optical system which has an image-forming action and provides a clear yet substantially undistorted image at a wide field angle. In a prism optical system 5 comprising an aperture 1 and having an action on erecting an image formed by an objective, there are provided reflecting surfaces 31, 32, 33, 41, 42, and 43 for image inversion, each of which is constructed of a curved surface having a power, and is in an irrotationally symmetric plane shape having no rotationally symmetric axis both within and outside the surface, so that decentering aberration produced by reflection of light at the curved surfaces can be corrected.

Abstract: An optical device for a system for the presentation of collimated images by a non-plane mirror, which makes it possible to present a user with an image corrected of distortion due to a non-plane mirror and exhibiting good resolution. To do this, the device includes a Mangin type mirror whose optical characteristics ensure good image quality of correction of off-centering distortion and good image sharpness. The Mangin type mirror has a reflecting surface and a layer of refracting material defining a refracting surface. One surface may be spherical, and the other aspherical. The surfaces may also be aspherical. One aspherical surface may be a paraboloid, an ellipsoid, or a torus. The refracting material can exhibit an optical index varying according to the position on the surface of the mirror. The device may be applied in particular to a system for the presentation of collimated images by a spherical mirror inclined with respect to the direction from which it is observed.

Abstract: The invention provides a real-image type finder optical system which is reduced in size in general and thickness in particular. In order from an object side of the system, the system comprises an objective optical subsystem having a positive refracting power, an image-inversion component for erecting a real image formed by the objective optical subsystem having only one image-formation action to an erect image and an ocular optical subsystem having a positive refracting power, with at least one of reflecting surfaces being defined by a roof surface. The objective optical subsystem comprises at least two reflecting surfaces of reflecting surfaces 12 to 14, each defined by a rotationally asymmetric surface with power imparted thereto.

Abstract: An optical virtual touch pad system wherein reflective optics are used to superimpose a virtual image of a television screen display onto a touch-sensitive digitizing surface being operatively contacted by a user-controlled contact member. Alternatively, the system uses reflective optics to superimpose an uninverted virtual image of the digitizing surface and the contact member operating thereon onto the surface of the display. The system thereby, for example, can be used as a user interface to control interactive content on a home television.

Abstract: The invention relates to a slimmed-down yet high-performance image display device which comprises a decentered prism capable of internal reflection and a reflection type image display device such as a reflection-type LCD or DMD and can present bright images to an observer, and provides an image display apparatus comprising a light source 5, a reflection type image display device 3, and an ocular optical system for guiding an image displayed on device 3 into an eyeball position for forming an intermediate image 4. The ocular optical system comprises a prism member 10 comprising an entrance surface 11 and two reflecting surfaces 12 and 13. In a prism, an optical path for connecting the first surface 11 with the second surface 12 intersects a reflecting optical path from the third surface 13. The ocular optical system further comprises a back-coated reflecting surface 23 between the third surface 13 and an observer's eyeball side.

Abstract: A method for monitoring the interaction of molecular species utilizes a sensor device comprising a substrate (1) with a waveguide (2) formed on the surface thereof. A grating (3) is formed in one of the surfaces of the waveguide (2). A beam of light (6) is incident on the grating (3) and the angle of incidence at which maximum reflection occurs is monitored. A first molecular species is immobilized on the waveguide (2). Changes in the angular position of the reflection maximum provide an indication of interaction of the first molecular species with a second molecular species contained in a sample brought into contact with the sensor device.

Abstract: Apparatus for forming multiple subimages including an image forming lens, a color separating prism, subimage receptors for receiving subimages from the prism, and lenses compensating for spherical aberrations caused by the prism and controlling the size of the subimages reaching the subimage receptors. Other features include structure for dissipating heat from the subimage receptors and from circuit boards associated with the subimage receptors.

Abstract: An optical element integrally has an optically acting surface, which is a rotationally asymmetric, aspherical surface, and a monitor surface for evaluation of whether the optical element is defective or not. The monitor surface is provided in a portion effecting no optical action, except for the optically acting surface.

Abstract: This invention is a method of adjusting a reduction projection exposure device having a light source, an illumination optical system, and a reduction image-forming optical system.

Abstract: A distortion-free and compact image-forming optical system with a minimal number of optical components which provides a wide image area and which is favorably corrected for ray aberrations and arranged in a compact structure by folding an optical path. A pentagonal prism member (5) has a first surface (1), a second surface (2), a third surface (3), and a fourth surface (4). The first surface (1) and the fourth surface (4) are refracting surfaces. The second surface (2) and the third surface (3) are reflecting surfaces. The first surface (1) is formed from a spherical surface. The second surface (2), the third surface (3) and the fourth surface (4) are formed from three-dimensional surfaces. Light rays from an object plane O provided on the back side of a cover glass (6) pass through the cover glass (6) and enter the prism member (5) through the first surface (1). The incident light rays are reflected successively by the second surface (2) and the third surface (3).

Abstract: A miniature display system uses a reflective micro-display that reflects light perpendicular to the surface of the display to generate an image. Light from an off-axis light source is polarized and reflected by a prism to provide on-axis illumination light for the display. The prism uses total internal reflection and/or a polarizer as a beam splitting surface so as to increase the brightness of the image generated by the display. The optical system provides a virtual image with a large field of view so that the small display system can be used in portable, hand-held or head mounted systems to display a large amount of information to the user.

Abstract: An image display apparatus which enables observation of a clear image at a wide field angle with substantially no reduction in the brightness of the observation image, and which is extremely small in size and fight in weight and hence unlikely to cause the observer to be fatigued. The image display apparatus includes an image display device and an ocular optical system for projecting an image formed by the image display device and for leading the projected image to an observer's eyeball. The ocular optical system (3) has three surfaces, and a space formed by the three surfaces is filled with a medium having a refractive index larger than 1.