Abstract: Provided is an optical apparatus that includes an illumination assembly which include an extended radiation source emitting radiation with a controllable spatial distribution and telecentric condensing optics, configured to receive and project the emitted radiation with a numerical aperture exceeding 0.3 along a first optical axis onto a field and an imaging assembly that includes a sensor and objective optics configured to image the field along a second optical axis onto the sensor and also a prism combiner positioned between the field and the condensing and objective optics which is configured to combine the first and second optical axes, while reflecting at least one of the optical axes multiple times within the prism combiner.

Abstract: The present disclosure concerns a light-field projection system, comprising a pin-light array generating an incident light-field illuminating an optical light modulator for modulating the incident light-field and projecting a plurality of modulated light-field components along a projection axis; a first optical element configured for forming first pin-light images in a first pin-light plane and modulator images in a modulator image plane; and a second optical element defining an eye-box region and for forming second pin-light images in a second pin-light plane within the eye-box; the first and second pin-light planes and the modulator image plane being substantially perpendicular to the projection axis; the system further comprising at least one optical device at the first pin-light plane and being configured for interacting with at least one of the modulated light-field components, spatially shifting the modulated light-field components in the modulator image plane.

Abstract: An electronic device is disclosed. An electronic device according to the present invention includes a display, first to third optical elements which are disposed to be dispersed on the display to emit red (R) light, green (G) light, and blue (B) light, an optical system which is installed in the display to combine light emitted from the first to third optical elements into the display, and a pinhole mirror which is installed on an illumination path of light combined by the optical system to reflect the combined light to eyeballs of a user. An electronic device according to the present invention may be associated with an artificial intelligence module, robot, augmented reality (AR) device, virtual reality (VR) device, and device related to 5G services.

Abstract: An optical system for use with a stereo video endoscope with a fixed, lateral viewing direction, including: laterally-viewing distal and proximal optical assemblies, similarly configured left and right lens system channels; the distal optical assembly couples incident light from an object space into the left and right lens system channels; the distal optical assembly includes an entrance lens, a deflection prism group and an exit lens in a direction of incident light; the deflection prism group includes first and second prisms in the direction of incident light; the first prism includes first entrance and first exit sides at an angle relative thereto; the second prism includes a second entrance side, a reflection side and a second exit side; and the first entrance side of the first prism and the reflection side of the second prism enclose an angle that is greater than a total reflection angle of the second prism.

Abstract: An imaging module includes a reflective display element, a prism device and a light absorbing element. The reflective display element includes a reflective display surface. The prism device includes first and second prisms. The first prism includes first, second and third surfaces. The second prism includes fourth, fifth and sixth surfaces. A stray light beam is incident into the first prism, passes through the third surface and then exits the first prism, then the stray light beam is incident into the second prism through the fourth surface, and then the stray light beam is reflected by the fifth surface and then exits the second prism. The light absorbing element is disposed on a transmission path of the stray light beam exiting the second prism. A projection device including the imaging module is also provided.

Abstract: An optical unit that directs illumination light to a plurality of digital micromirror devices that produce projection light by modulating the illumination light on an image display surface according to an image signal, and that transmits and emits the projection light, the optical unit includes: a plurality of first prisms, wherein the projection light exits a first face of a most emergence-side first prism among the first prisms; and a second prism disposed next to the first prisms, wherein the second prism includes: a 2A-th face into which the projection light enters; and a 2B-th face disposed perpendicular to an optical axis of the projection light, the projection light exits the 2B-th face, the second prism is wedge-shaped with the 2A-th and 2B-th faces not being in parallel with each other.

Abstract: A wearable display includes a first optical section, a main body, and a jig receiver. The first optical section emits light. The main body includes a second optical section that is connected to the first optical section and outwardly emits the light as image light, and a casing that supports the second optical section. The jig receiver includes a first guide that supports a first protrusion of a jig, a second guide that supports a second protrusion of the jig, and a third guide that supports a third protrusion of the jig. The jig receiver is provided in the casing such that at least two of the first, second, and third guides are spaced apart from each other in the first axis direction and at least two of the first, second, and third guides are spaced apart from each other in the third axis direction.

Abstract: It is provided a method for viewing an image that is wider or higher than the display screen, wherein, the image is evenly divided into two portions by using a line passing through centers of larger edges of the image compared to the display screen. The method comprises, at the side of shutter glasses, the steps of receiving a message indicating display of a first portion of the two portions; turning dark of the shutter glasses and turning refraction direction of the shutter glasses towards a first position; turning transparent of the shutter glasses; receiving a message indicating display of a second portion of the two portions; turning dark of the shutter glasses and turning refraction direction of the shutter glasses towards a second position; and turning transparent of the shutter glasses.

Abstract: An illumination optical system includes a lens group, a diaphragm, and a prism unit including first to third prisms and a rotationally-asymmetrical curved reflective surface having a positive power and satisfying the conditional formula: PYa/PZa<PYb/PZb, where Pya, Pyb represent powers of the curved reflective surface at positions of points a, b, respectively within a reference plane formed in the prism unit by rays passing through centers of the lens group and the diaphragm, and PZa, PZb represent powers of the curved reflective surface at positions of points a, b, respectively, within a plane including normal lines of the reference plane and the curved reflective surface, points a and b representing where the principal ray of a beam illuminating the area nearest and farthest, respectively, to the lens group impinges on the curved reflective surface, along an intersection line between an image display surface and the reference plane.

Abstract: A projector includes an illumination device adapted to emit an illumination light beam, an image forming device adapted to modulate the illumination light beam emitted from the illumination device to form an image, a projection optical device adapted to project the image formed by the image forming device, and a light guide device adapted to guide the illumination light beam emitted from the illumination device to the image forming device, and defining two directions which are propagation directions of the illumination light beam propagating inside the image forming device, and cross each other as a first direction and a second direction, the image forming device is disposed so that at least a part of the image forming device overlaps at least a part of the illumination device in a third direction perpendicular to each of the first direction and the second direction.

Abstract: A projection film and a projection device are provided. The projection film includes a pattern layer, a first light-transmission layer, a second light-transmission layer and a plurality of light-transmission particles. The pattern layer includes a light-transmission portion and a non-light-transmission portion. The first light-transmission layer is disposed below the pattern layer. The second light-transmission layer is disposed below the first light-transmission layer. The light-transmission particles are disposed between the first light-transmission layer and the second light-transmission layer. The impurity generated by the light-transmission particles will be reduced by utilizing a second light-transmission layer having a refractive index close to the refractive index of the light-transmission particles.

Abstract: A compact illuminator for a see-through image display system with highly uniform light distribution is disclosed. This invention enables wearable displays such as eye-glass type see-through display. This system provides a wide divergent beam from a display device so that a viewer can have a large eyebox.

Abstract: A prism unit includes: a color synthesizing prism; a fixing member having a linear expansion coefficient different from a linear expansion coefficient of the color synthesizing prism; and a first adhesive layer and a second adhesive layer, wherein the color synthesizing prism is adhered to the fixing member via the first adhesive layer and the second adhesive layer which are arranged in this order sequentially from the fixing member, and the second adhesive layer has a lower tensile strength than the first adhesive layer.

Abstract: A projector includes an illumination system, a biaxially-tilted digital micromirror device (DMD), a first prism, a second prism and a lens. The illumination system provides an incident light. The biaxially-tilted DMD having two opposite first long sides and two opposite first short sides receives the incident light and converts the incident light into an image light. The first prism is disposed between the illumination system and the DMD, and includes a first face and a second face connected and adjacent to the first face. The second prism is disposed between the first prism and the DMD and includes a third face, a fourth face and a fifth face; and the third face is connected and adjacent to the fourth face and fifth face. The fourth face has two opposite second long sides and two opposite second short sides. The lens receives and projects the image light.

Abstract: A projection type display apparatus includes illumination unit that emits a plurality of color lights having a predetermined polarization direction, a plurality of optical path adjustment units that totally reflect the plurality of color lights, respectively, a plurality of optical modulation units that modulates the plurality of color lights totally reflected by the plurality of optical path adjustment units, respectively, to emit a plurality of modulated color lights, a synthesis unit that emits the plurality of modulated color lights emitted from the optical modulation units in a same direction, and a correction unit that is arranged on an optical path between the illumination unit and the synthesis unit and that changes a polarization state of light that entered the correction unit to covert light incident on the synthesis unit into linearly polarized light.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: A solid state illuminator for generating time sequential 6-primary color includes a first light source, a second light source, a path choosing module, a multi-band filter, a first photoluminescence module, a second photoluminescence module, a first optical module, and a second optical module. The first light source and the second light source provide a first beam with a first wavelength and a second beam with a second wavelength respectively, and the first wavelength is not overlapped with the second wavelength. The first optical module enables the first beam to enter the first photoluminescence module and guide the beam to pass through the multi-band filter to arrive at a predetermined position. The second optical module enables the second beam to enter the second photoluminescence module and guide the beam to be reflected by the multi-band filter to arrive at the predetermined position.

Abstract: An apparatus comprises a passive wavelength division multiplexing (WDM) demultiplexer (DeMUX) or a passive WDM multiplexer (MUX), an active photo diode (PD) array or an active laser diode (LD) array, and a compressing device disposed between the passive WDM DeMUX or the passive WDM MUX and the active PD array or the active LD array. The compressing device changes the optical spot pitch of the passive WDM DeMUX or the passive WDM MUX to match the pitch of the active PD array or the active LD array. The compressing device may be a single optical wedge, a first and a second optical wedges, a plurality of optical wedges, or a grating. A compression ratio can be adjusted by changing the incident angle of the incident beam to the compressing device.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: A light source system for stereoscopic image is disclosed, which includes a first multiband filter, a second multiband filter, a first relay lens assembly, a second relay lens assembly, a light source module, a light outputting portion and a light valve device. The first and the second relay lens assemblies are disposed between the first multiband filter and the second multiband filter. The light source module and the first multiband filter are together disposed at one side of the first relay lens assembly. The light outputting portion and the second multiband filter are together disposed at one side of the second relay lens assembly. The light valve device is disposed between the first and the second relay lens assemblies. Therefore, the light source system configures the light path by controlling the light valve device and produces beams with different bands.

Abstract: A magnification optical system forms an enlarged image of an object. It includes a refractive optical system including a plurality of lens groups; and a mirror train including a curved mirror, arranged in this order from an object side, a first focus structure configured to move the respective lens groups of the refractive optical system by different amounts along a normal line of a conjugate surface on the object side, and a second focus structure configured to move the respective lens groups along the normal line of the conjugate surface on the object side by different amounts from those of the first focus structure.

Abstract: A LCOS projection system includes an illumination device, a LCOS microdisplay element, a polarization beam splitter, an optical projection lens, and a beam recycling module. A first portion of the lighting beams provided by the illumination device are transmissible through the polarization beam splitter and directed to the LCOS microdisplay element. A second portion of the lighting beams provided by the illumination device and from the polarization beam splitter are introduced into the beam recycling module. By the beam recycling module, a polarization state of the second portion of the lighting beams is converted. Consequently, the second portion of the lighting beams in the converted polarization state can also be projected onto the LCOS microdisplay element. The beam recycling module includes a total internal reflection prism, which is arranged in a transmission path of the first portion and the second portion of the lighting beams.

Abstract: A projecting apparatus is disposed within a space defined with first, second and third imaginary planes perpendicular to one another and includes a light source, a prism, a reflecting mirror, and a reflective light valve. The light source emits a light beam propagating along a first optical path parallel with the first and second imaginary planes. The prism is disposed in the first optical path, and refracts the light beam to propagate along a second optical path. The reflecting mirror is disposed in the second optical path, and reflects the light beam to propagate along a third optical path. The reflective light valve is disposed in the third optical path, and has an active plane parallel with the second imaginary plane. Therefore, the light source can be placed horizontally with respect to the reflective light valve to reduce the space occupied by the light source.

Abstract: A compact optical projection apparatus. An apparatus for light projection includes at least one illumination device; a cover prism including a curved surface positioned to receive illumination light rays and a total internal reflection surface positioned to internally reflect the light rays towards an asymmetric reflector surface positioned opposite the total internal reflection surface, the asymmetric reflector surface configured to reflect the received light rays out of the cover prism at an emitter side of the cover prism; a spatial light modulating the illumination light rays with image data to form image light rays; a reverse total internal reflection (RTIR) prism positioned between the spatial light modulator and the emitter side of the cover prism and further comprising a total internal reflection surface configured to totally internally reflect the image light rays out of the RTIR prism into a light projection device. Additional apparatus are disclosed.

Abstract: An optical projection and image sensing apparatus including a light source, a light valve, a first lens set, a sensing module, and a beam splitter is provided. The light valve is used to convert an illumination light from the light source to an image light beam. The first lens set is used to project the image light to display an image on a screen, and the sensing module is used to sense a sensing light from the image on the screen. The beam splitter is disposed on the optical paths of the image light and the sensing light from the image on the screen. One of the sensing module and the light valve is disposed on the optical path of the sensing light passing through the beam splitter, and the other is disposed on optical path of the sensing light reflected by the beam splitter.

Abstract: A heat dissipation device of a light engine for a projector has a housing, a fan module, a light engine and a heat sink. The light engine is positioned in the housing and connected to the heat sink. The heat sink is positioned out of the housing. The housing has a fan-enclosed flow channel attached on an outer surface of the housing. The fan module is guided by the fan-enclosed flow channel to the heat sink to enhance heat dissipation efficiency of the light engine for the projector.

Abstract: An optical device, includes a light-transmitting substrate (20) having an input aperture and first and second major surfaces (26, 32) parallel to each other and edges, one partially reflecting surface located in the substrate which is non-parallel to the major surfaces of the substrate and an external optical arrangement having an output aperture for coupling light into the substrate by total internal reflection. The optical arrangement for coupling light having an output aperture optically attached to the input aperture of the substrate with the part of the substrate located next to the substrate input aperture, being substantially transparent.

Abstract: A system is provided for projecting a three-dimensional image. The system includes a light source and a polarization conversion system for converting light emitted from the light source to circular polarization. A beam splitter device is disposed adjacent the light source to receive light, and an LCoS image device is disposed adjacent the beam splitter device.

Abstract: Embodiments of the present invention provide a method, apparatus and system of producing a color image using four or more primary colors. The apparatus, according to some demonstrative embodiments of the invention, may include four or more transmissive spatial light modulators to modulate four or more, respective, primary color light beams in accordance with four or more, respective, primary color image components of the color image to produce four or more, respective, modulated light beams; and a beam combiner to combine the four or more modulated light beams into a combined light beam carrying the color image. The beam combiner may include, for example, an X-cube to jointly direct three of the four or more modulated light beams; and a selective color rotator to rotate the polarization of two of the three modulated light beams, while maintaining the polarization of a third one of the three modulated light beams. Other embodiments are described and claimed.

Abstract: Speckle effect in scanning display systems that employs polarized phase-coherent light is reduced by depolarizing the phase-coherent light using a depolarizer and scanning the depolarized light for producing desired images.

Abstract: The invention pertains to a projector comprising an optical engine, a projection lens, a means for light deviation, and an afocal lens system, wherein the projector has a total throw ratio between 0.7 and 0.8. Such a projector can be used to build a very compact and cost-effective back-projection system. The invention also pertains to a projection assembly comprising such a projector, followed by a means for light gradation and a front-surface mirror. The invention also pertains to a display system comprising at least one such projection and a display screen.

Abstract: An image display apparatus includes: a laser light source for outputting a laser beam; a diffusion optical element for diffusing the laser beam; a drive unit for oscillating the diffusion optical element; and an image conversion unit for converting the laser beam output from the diffusion optical element into an image. The diffusion optical element disposed in the drive unit is oscillated and operated in a state where an amplitude of the drive of the drive unit, which is, for example, an amplitude that is driven in a direction of the arrow X in a plane that is perpendicular to an optical axis, is not constant.

Abstract: A method is provided that includes providing a light source having a light emitting diode (LED) that emits a light. A polarization conversion system (PCS) is located adjacent the LED and has both a linear polarizer and a wave plate. A polarizing beam splitter (PBS) is adjacent the light source and an imaging device is adjacent the PBS. The wave plate of the PCS is rotated to a first position, and a first light is emitted by the LED in the first light source. This first light is converted to circular polarization. This first light travels to the PBS where it is reflected onto the imaging device. The wave plate is then rotated to a second position, and a second light is emitted by the light source. This second light is converted to circular polarization and reflects from the PBS onto the imaging device.

Abstract: An electronic device is provided in the disclosure. The electronic device includes a body, a display unit, and a projecting unit; where the body comprises a first surface and a second surface which intersects the first surface, where the second surface supports the body in a standing position on a support surface at a first angle which is not zero degrees between the second surface and the support surface; the display unit is disposed on the first surface and displays content; and the projecting unit is supported by the body and projects content externally when the body stands on the support surface.

Abstract: A technology reducing the number of components in a projector. Illuminating light from a lamp is made incident from a first surface of a TIR prism via an optical system, reflected, output from a second surface of the TIR prism, optically modulated by a DMD, and made incident to the second surface of the TIR prism. Projection light from the DMD is transmitted through the TIR prism, emitted from a third surface of the TIR prism, and enlarged by a projection lens, to form an image on a screen. Light from a light emitting element is reflected by the screen, made incident to the third surface of the TIR prism via the projection lens, reflected, and output from a fourth surface of the TIR prism, to form an image on an imaging element.

Abstract: A micro projection system includes a primary prism as a light guide device. The primary prism has a bottom face and two slope faces. A light source module and a collimation lens are arranged at the bottom face of the primary prism to project red, green, and blue lights onto one of the slope faces of the primary prism to be consolidated by a wedge prism group and reflected toward a polarization beam splitting wedge prism arranged at another slope face, where the light is split into two polarized lights that are then emitted out of the primary prism to be processed and combined as light of consistent polarization by a lens array and a polarization conversion film so as to facilitate condensation and projection of the light by a polarization beam splitter and a projection lens.

Abstract: Embodiments of the present invention provide apparatuses and systems for providing illumination for projectors. One or more beam combiners are used to combine multiple light beams to provide a combined light beam toward to a pupil of an imaging device in a projector. Solid state light sources, such as diode lasers and light-emitting diodes (LEDs), may be used as light sources at relatively low cost and low power, and with long lifetime. In one embodiment, an optical beam combiner comprises a first reflective surface, a second reflective surface, and a transparent region disposed between the first reflector surface and the second reflective surface. In another embodiment, an optical device comprising an array of optical beam combiners is provided. In a further embodiment, light sources comprising a plurality of light-emitting devices mounted on curved surfaces are utilized in conjunction with an optical beam combiner to provide illumination for a projector.

Abstract: An image projection apparatus has a corrector that corrects angle distribution of illumination light such that, let, in a comparison in traveling direction between, of diffracted light resulting from light rays with the wavelengths ?1 and ?2 along the illumination optical axis being diffracted on an on-state digital micromirror device, ?1 diffracted light traveling in a direction closest to a traveling direction of the mirror-reflected light and ?2 diffracted light traveling in a direction closest to the traveling direction of the mirror-reflected light, the ?1 diffracted light be diffracted to a position farther away from the mirror-reflected light than the ?2 diffracted light, the angle distribution of the illumination light includes at least an angle distribution that fulfills conditional formula (1): F?2<F?1, where F?1 and F?2 represent F-numbers of illumination light with the first and second wavelengths ?1 and ?2, respectively.

Abstract: The image projection apparatus includes light modulation elements, a color separation/combination optical system (?) configured to, in a specific cross section, separate light source light into plural color lights, introduce the color lights to the corresponding light modulation elements, combine the modulated color lights and introduce the combined color lights to a projection optical system, a holding member holding the color separation/combination optical system, an electrical circuit substrate attached to the holding member parallel to the specific cross section and electrically connected to the light modulation elements, and an optical element insertable into and extractable from the color separation/combination optical system. The holding member has a configuration allowing, in a direction orthogonal to the specific cross section on an opposite side to an electrical circuit substrate side, the insertion/extraction of the optical element into and from the color separation/combination optical system.

Abstract: A projection apparatus is disclosed. The projection apparatus includes a light source module, a first light splitting element, a first light valve unit, a first light modulator, a second light modulator and a light consolidating element. A light beam is provided by the light source module, and is split into a first and a second polarized light beam by the first light splitting element. In different time sequences, the first and the second polarized light beams are formed into a first, a second, a third and a fourth image light by the first light valve unit. Then, these image lights are transformed into viewing angle images by the first and the second light modulators. Then, via the light consolidating element, the first, the second, the third and the fourth view angle images are projected to a viewer and a stereoscopic image is formed.

Abstract: A light source device includes: a first light source (3a) that emits first polarized light of a plurality of colors including different wavelengths; a second light source (3b) that emits second polarized light whose polarization state differs from that of the first polarized light and that includes light of at least one color from among the plurality of colors; and a first color synthesis optical element (1) that synthesizes the first polarized light emitted from the first light source (3a) and the second polarized light emitted from the second light source (3b).

Abstract: In addition to reflective light modulation devices, reflective polarization plates, a color combining optical device, and support bodies, a projector is provided with connection members fixed to the color combining optical device and for supporting the support bodies. Support positions of the support body by the connection members are disposed on the opposite side to the disposition position of the reflective light modulation device with respect to a plane including a polarization split surface of the reflective polarization plate.

Abstract: A projector is provided, including a first light source, a second light source, a splitting unit, a first modulating element, a second modulating element, a projection lens unit, a projection screen and a combining unit. The first light source provides a first beam in a first state. The second light source provides a second beam in a second state. The splitting unit receives the first beam and the second beam, splitting the first beam into a first sub-beam and a second sub-beam, and splitting the second beam into a third sub-beam and a fourth sub-beam. The first modulating element receives the first sub-beam and the third sub-beam from the splitting unit. The second modulating element receives the second sub-beam and the fourth sub-beam from the splitting unit. The combining unit respectively combines the first sub-beam and the second sub-beam, and combines the third sub-beam and the fourth sub-beam.

Abstract: An optical unit includes a light source that emits light to be projected onto a screen, one or a plurality of optical elements that controls a spread of a beam of light from the light source to the screen, a combining element that combines the light emitted from the light source, and a scanning element. The light source outputs an optical beam that will generate an elliptically shaped beam spot on the screen, the beam spot having a major axis substantially perpendicular to a scanning direction, and the light source is driven with pulse width modulation (PWM) so that one driven pulse corresponds to one beam spot on the screen.

Abstract: A projector includes an anamorphic prism optical system for converting an aspect ratio of an irradiation region on which the video light is irradiated. The anamorphic prism optical system includes a first prism set and a second prism set. The first prism set is obtained by combining a first prism and a second prism, and the second prism set is obtained by combining a third prism and a fourth prism. The first prism, the second prism, the third prism, and the fourth prism are respectively rotatable around rotation axes thereof, and a space between the first and second prism sets is adjustable in association with the rotation of the first prism, the second prism, the third prism, and the fourth prism.

Abstract: A projection display device includes: a light source unit including light sources emitting light in a plurality of colors, condenser lenses and a color combining optical element; a total reflection prism that totally reflects a combined light flux from the color combining optical element so as to be guided to an image forming unit; and a projection lens. At least one of; an entry surface of the color combining optical element through which substantially parallel light fluxes from the condenser lenses enter, an exit surface of the color combining optical element through which the combined light flux exists, and an entry surface of the total reflection prism through which the combined light flux enters, is formed as a free curved surface where a shape of a section of the combined light flux is altered so as to be matched with a shape of an outline of the display area.

Abstract: A light dividing structure used in an optical machine system of a projection apparatus is provided. The light dividing structure includes a first prism, a second prism, a third prism and a fourth prism. The first prism includes a first exiting surface, a first reflecting surface, a first concave portion and a second concave portion. The second prism is disposed on the second concave portion and is adjacent to the first prism. The third prism includes a second exiting surface, a second reflecting surface, a third concave portion and a fourth concave portion. The fourth prism is disposed on the fourth concave portion and is adjacent to the third prism and the first prism. The first prism, the second prism, the third prism and the fourth prism are connected together sequentially.

Abstract: The polarization beam splitting element splits an entering beam according to polarization directions. The element includes, in order from a beam entrance side, an entrance side multi-layered film layer constituted by laminated multiple dielectric films, and a one-dimensional grating structure having a grating period smaller than a wavelength of the entering beam and formed of a metal. When a medium existing on the beam entrance side further than the entrance side multi-layered film layer is referred to as an entrance medium, the multiple dielectric films constituting the entrance side multi-layered film layer include at least one dielectric film having a higher refractive index than that of the entrance medium and at least one dielectric film having a lower refractive index than that of the entrance medium.

Abstract: An image display apparatus for a viewer to view a two-dimensional image demonstrated on an image display device as an enlarged virtual image by a virtual-image optical system. The image display apparatus includes a prism and a reflective transmitting surface for reflecting or transmitting image light incident from an incident optical surface. The image display apparatus also includes a reflective optical component for reflecting image light reflected from the reflective transmitting surface and radiated from a first planar optical surface towards the reflective transmitting surface as a collimated light beam and a phase difference optical component arranged on a light path between the first planar optical surface and the reflective optical component to the state of polarization of the image light.