Abstract: A display system is provided that includes a spectral separator configured to separate multispectral light into a plurality of light bands, and a homogenizing element configured to homogenize at least one separated light band.

Abstract: The light-guiding apparatus has a light tunnel and an ellipsoidal reflector. Light emitted from the light tunnel is reflected and focused on a DMD chip by the ellipsoidal reflector. The light tunnel and a long axis of the ellipsoidal reflector form an angle. The angle and an eccentricity of the ellipsoidal reflector are used to modify the light emitted from the light tunnel. Thus, the light is made to match an incident angle and an effective dimension of a digital micro-mirror device receiving the light.

Abstract: In a projector optical system comprising a digital micromirror device for modulating illumination light, a device having a polarization separating surface is provided for separating a luminous flux incident on the digital micromirror device and a luminous flux emitted from the digital micromirror device from each other. A device for rotating a polarization direction is disposed between the polarization separating surface and the digital micromirror device.

Abstract: A liquid crystal projector of three-color type has three liquid crystal elements for modulating three primary color light bundles into three color optical images respectively. A recombination prism combines modulated three color optical images, and a projection lens system projects the combined full-color image on a screen. The projection lens system is constituted of the front lens group and the first and second rear lens groups. The front lens group and the rear lens groups are mounted to frames that are formed integrally on a prism base plate to which the recombination prism is fixed.

Abstract: In a reflective liquid crystal projector, illumination light is separated into blue, green and red illumination light bundles. The three color illumination light bundles are respectively modulated through three reflective liquid crystal elements into blue, green and red color optical images. A first polarizing beam splitter prism directs the blue optical image to a first incident surface of a recombination prism, whereas a second polarizing beam splitter prism directs the red and green optical images to a second incident surface of the recombination prism. The three color optical images are recombined through the recombination prism into a full-color image, and the full-color image is projected through a projection lens onto a screen. The first and the second polarizing beam splitter prisms and the recombination prim are fixed merely at their bottom surfaces to a prism base plate.

Abstract: A digital projection display includes a light source producing a light beam, and an integrator, an illumination lens, an illumination fold mirror, a light director, and a digital light modulator which sequentially process the light beam. The digital projection display further has a projection lens that receives the spatially modulated light beam from the light director and includes two projection lens elements. A projection lens fold mirror is disposed between the two projection lens elements. A projection fold mirror receives the light beam from the projection lens and redirects the light beam to a display.

Abstract: A projection display includes a light source, a spatial light modulator that receives a light from the light source, and an angle-selective coating disposed to receive the light beam from the spatial light modulator. The angle-selective coating is oriented at a non-zero inclination angle to the light beam. The angle-selective coating has a higher transmission for light that is incident upon the angle-selective coating at an incidence angle within an acceptance-angle deviation from a design incidence angle, than for light that is incident upon the angle-selective coating at an incidence angle greater than the acceptance-angle deviation from the design incidence angle. The projection display preferably includes a TIR (total internal reflection) prism disposed to reflect a light beam from the light source to the spatial light modulator, and to receive the light beam from the spatial light modulator. The angle-selective coating is preferably buried within the TIR prism.

Abstract: A projector apparatus includes a color separation optical system which separates illumination light into color light components, image forming panels illuminated with the color light components, respectively, a color synthesis optical system which synthesizes the light components from the illuminated image forming panels, and a projecting optical system which projects light from the color synthesis optical system. Transparent substrates are arranged on at least one of incident and exit surface side of the image forming panels. Each of the transparent substrates holds a polarizer. A surface area of at least one of the transparent substrates is larger than those of the remaining transparent substrates.

Abstract: A color-separating and -recombining optical system provided between a light source and a projection lens in a projection display, has at least one prism assembly made up of at least two prisms bonded to each other with a bonding layer formed between the prisms. A white light emitted from the light source is divided into red-, green-, and blue-color light components related to primary colors. The light components are modulated by spatial light modulators in accordance with a video signal. The modulated light components are combined and projected onto a screen via the projection lens. The thickness of the bonding layer is varied as thin and thick for optical paths long and short, respectively, from the spatial light modulators to the bonding layer which each modulated light component emitted from the corresponding spatial light modulator reaches.

Abstract: A convergence system 100 comprises a dichroic prism 102 for splitting and/or recombining light beams, intermediate parts 104a, 104b, 104c and a light modulator 106a, 106b, 106c for every color beam. The intermediate parts 104a, 104b, 104c are constructed such that the convergence system has an improved resistance for variations in environmental effects like temperature and humidity. The intermediate parts 104a, 104b, 104c are constructed such that the convergence system has a high stability, a large degree of monolithicy and a high movement isotropy. When used in a projection display system, the projection display system has a high degree of color uniformity.

Abstract: An apparatus is provided which maintains alignment of panels in a projector. The apparatus includes a synthesizing system holding device positioned at an upper portion of a synthesizing system of the projector which securely supports the synthesizing system and maintains a relative position of various components of the synthesizing system, even in the event of an external force or vibration applied to the projector. This apparatus can prevent deviation or misalignment between at least two or more prisms and panels in the synthesizing system of the projector, thereby improving reliability and durability of the projector and enhancing image quality.

Abstract: A two level image writer (10) forms an image from digital data onto a photosensitive medium. A first level illumination system has a first source (20) for emitting a first polarized light beam having a first color; a second source (22) for emitting a second polarized light beam having a second color; and a third source (26) for emitting a third polarized light beam having a third color. A fold mirrors directs each beam to a second level. Three polarizing beamsplitters (73, 75, 77) on the second level receive the polarized beams from the fold mirrors and isolate polarization states of each of the first, second, and third polarized light beam. Three spatial light modulators (90, 95, 97) on the second level modulate the first, second, and third polarized light beam from the polarizing beamsplitter prisms to form an array of image pixels according to said digital data. A diechroic combiner (86) combines the three modulated light beams.

Abstract: Optical systems for projection optical devices which employ reflective LcoS panel (9, 14, 15) are provided. The systems provide high contrast, compact size, and high light throughput.

Abstract: A digital light processing projection system includes an illuminating device, an optical-path-switching element, a projection device and a prism set. The prism set is arranged between the illuminating device, the optical-path-switching element and the projection device and has a plurality of prisms in which an air gap existing between any two adjacent prisms. According to the invention, a light beam output from the illuminating device directly passes through the prisms and air gaps before being received by the optical-path-switching element. Under a first state, a light beam reflected from the optical-path-switching element is totally reflected at an interface between one of the prisms and one of the air gaps before being received by the projection lens. Under a second state, a light beam reflected from the optical-path-switching element is totally internal reflected back and forth within a prism being adjacent to the optical-path-switching element and is absorbed by a light absorbing material.

Abstract: There is provided a small-sized and light-weight image display apparatus which is thinned in the line of sight and which incorporates a display unit for displaying a magnified virtual image and a direct image, the display apparatus comprising a real image display part for displaying an image, an image magnifying means for optically magnifying the image formed in the real image forming means so as to form a virtual image, and a light guide means for guiding light from the real image display part to the image magnifying means, the magnifying means being formed in a triangular columnar shape having a substantially isosceles triangular cross-section, and having a first surface serving a light incident surface, a light emanating surface and a reflective surface, and a first internal reflecting surface and a second internal reflecting surface for reflecting light into the light guide means, wherein emanating light from the real image display part is incident upon the light guide means through the first surface, and

Abstract: In a projection type image display apparatus, when the angle of light incident on the multi-layer film of a polarizing beam splitter for synthesizing an optical path becomes uneven, the loss of the light occurs.

Abstract: A color combining optical system according to this invention aims at reducing the size of an optical system and suppressing the occurrence of color unevenness. According to this invention, there is provided a color combining optical system for combining color light reflected by a dichroic film and color light transmitted through the dichroic film. The optical thickness of the dichroic film increases or decreases from one end side to the other end side in the inclining direction of the dichroic film with respect to the incident optical axis of the color light reflected by the dichroic film.

Abstract: The invention includes a color projection system comprising having a light source optically coupled to a light management device. The light management device being optically coupled to a polarizer. The color projection system also includes a projection lens optically coupled to the polarizer. Additionally, a plate is disposed between the polarizer and the projection lens. The plate has quarter-wave properties. The light management device has a number of polarizing beamsplitter (PBS) cubes, with one or more subsets of which are optically coupled to each other, and at least one light blocking region disposed between a first and a second PBS cube of the number of PBS cubes. As result reduction of stray light in a reflective projection system is facilitated.

Abstract: The present invention provides a unique polarizing beam splitter (PBS) that is suitable for use in projection systems and displays. The PBS contains at least one prism having at least one major surface and having a refractive index of at least about 1.6 and a birefringent film disposed on the major surface of the prism. The birefringent film is a multi-layer film having at layers of at least a first material and a second material. After uniaxial stretching, the film exhibits a refractive index difference of less than about 0.15 units in the stretched direction.

Abstract: A measurement light (X) is introduced on either one of reflection surfaces (501, 502, 511, 512) to detect a returned light (Y) reflected by the reflection surfaces (501, 502, 511, 512), reflected by a reflecting device and again reflected by the reflection surfaces (501, 502, 511, 512) by an autocollimator (620) to conduct image-processing and calculation by a processor (628), where a position adjuster (690) adjusts an attitude of a cross dichroic prism (45) relative to a fixing plate (447) to eliminate deviation between a position of the measurement light (X) and the returned light (Y) based on the result of the processing, thereby producing a highly accurate prism unit (50).

Abstract: Methods for measuring the low spatial reflectivity uniformity of a DMD spatial light modulator. These methods are unique since they compensate for the non-uniformities introduced by the tilt angle of the DMD mirrors in addition to the normal system non-uniformities introduced by the illumination source and optics. These methods flatten the image and remove all but the low spatial non-uniformities from the DMD mirrors.

Abstract: A color separation device according to the present invention comprises a first color separation member having a first polarization direction changing element and a second polarization direction changing element, and a first polarization separation element, and a second color separation member having a second polarization separation element. The first color separation member may be configured from a color separation function element and a polarization direction changing element.

Abstract: An optical system for enhancing the image contrast and shortening the back focal length of a projection display is disclosed, which includes a light source, a light path switching device, and a total internal reflection (TIR) prism set disposed between the light path switching device and the projection lens. The light path switching device has a first mode of operation for directing the light towards a projection lens and a second mode of operation for directing the light away from the projection lens. The TIR prism set includes a first prism, a second prism and a third prism; a first gap is formed between the first prism and the second prism, and a second gap is formed between the first prism and the third prism.

Abstract: In a light beam sensor (40) of a position adjuster, a light beam irradiated from a cross dichroic prism (150) is directly received by a CCD camera (41) via a beam splitter (451), so that the position adjuster can be adjusted without using a conventional projection screen and great size reduction of the position adjuster is possible, and, since only small space is required for installing the position adjuster, workspace can be efficiently utilized.

Abstract: In a projection display apparatus that analyzes to pick up lights emitted from a plurality of the reflective light valves, color-composes the analyzed lights and projects the color-composed light, a dichroic film is disposed in at least one of optical paths of the respective color lights between the polarizing beam splitters and the dichroic prism. The dichroic film reflects such a component of a color light derived from the composite light incident on the projection optical system that has been reflected by a surface of a lens element constituting the projection optical system and incident on the dichroic prism after passing through a quarter wave phase plate and reflected or transmitted by the dichroic film within the dichroic prism to travel along the optical path of the color light in the reverse direction, thereby deflecting the color light component out of the optical path.

Abstract: A color separation beam splitter for projectors is provided, which comprises a plurality of prisms connected with each other and three optical interference filters having different wavelength ranges respectively formed on side surfaces of the plurality of prisms. The three optical interference filters include a yellow color reflective dichroic mirror, a red color reflective dichroic mirror, and a blue color reflective dichroic mirror to filter out the yellow light and provide three primary color lights with high color purity. Moreover, by reflecting a light beam twice, the number of layers of dichroic mirror can be reduced. The color purity of the light is increased after reflected twice by the dichroic mirrors. Moreover, configuration of a liquid crystal projector by use of this prism assembly as color separation unit is also disclosed.

Abstract: An optical device (44) is provided with an optical modulator (440), a color combining optical device (444) and an optical converting element (443), the optical modulator (440) being attached to the color combining optical device (444) through a position-adjusting spacer (449) made of a heat-insulative material, so that heat generated on the optical modulator (440) and the optical converting element (443) is mutually insulated by the spacer (449) made of heat-insulative material and does not conduct from high-temperature side to low-temperature side between the optical modulator (440) and the optical converting element (443), thus improving cooling efficiency of the optical modulator (440) to enable size reduction and high luminance of the optical device (44) and a projector.

Abstract: Disclosed is a projector apparatus including a color separation optical system which separates illumination light into a plurality of color light components, a plurality of image forming panels illuminated with the plurality of color light components, respectively, a color synthesis optical system which synthesizes the light components from the plurality of image forming panels illuminated, a projecting optical system which projects light from the color synthesis optical system, and transparent substrates each arranged on at least one of incident and exit surface sides of the plurality of image forming panels, each of the transparent substrates holding a polarizer, wherein a surface area of at least one of the plurality of transparent substrates is larger than those of the remaining transparent substrates.

Abstract: A highly efficient projection system, including a light source, a scrolling unit, a color separation hologram, a light valve, and a projection lens unit. The scrolling unit includes spirally arranged cylinder lens cells to scroll/cycle incident beams while rotating. The color separation hologram separates a beam radiated from the light source into beams with different wavelengths. The light valve forms a color image by turning on or off pixels according to an input image signal. The projection lens unit magnifies the image formed by the light valve and projects the magnified image toward a screen. In this projection system three color beams from the light source are scrolled simultaneously to produce a picture, resulting in a highly light efficient projection system.

Abstract: An improved system is disclosed for displaying multi-image or animated holograms, in which the light that is used to illuminate the hologram is reflected to the hologram through one or more mirrors, and the angle at which the incoming light illuminates the hologram is varied over time.

Abstract: Disclosed is a polarized-light converting unit, which is excellent in contrast performance and realizes high reliability and an increase in its life, and a projector device using the converting unit. The polarized-light converting unit includes first and second polarizing beam splitters provided in an integral form. The first polarizing beam splitter includes two incident planes on which two types of color light are respectively incident. The second polarizing beam splitter includes both a ¼-wave plate and first dichroic mirror, and a ¼-wave plate and a second dichroic mirror, both of which are disposed on two adjacent surfaces different from a junction surface with the first polarizing beam splitter and an outgoing surface thereof.

Abstract: A projection apparatus (10) forms a tiled image (12) on a display surface (14), the tiled image (14) having at least two adjacent image tile segments. The projection apparatus (10) includes an illumination system (16) for providing a first illumination beam having a first polarization state and a second illumination beam having a second polarization state, these illumination beams being substantially non-overlapping. First and second spatial light modulators (20) form first and second modulated light beams from their respective illumination beams. A beam aligner (40) directs these first and second modulated light beams along adjacent parallel paths, in the direction of the optical axis of a projection lens (18). The projection lens (18) directs the first and second modulated beams to the display surface (14) to form the first and second tile segments respectively.

Abstract: The addition of DMD illumination modulator(s) 702 in series with projection SLM(s) 706/709 to produce high-performance projection displays with improved optical efficiency, reliability, and lower maintenance requirements. This approach eliminates the vibration, audible noise, and safety problems associated with high speed rotating color filter wheels 203 commonly used in SLM projectors and controls the light applied to individual areas of the projection SLM(s).

Abstract: A three element prism system and method for splitting/combining three different colors of light arranged such that the size of a selected one of the color prism, such as for example, the red prism and, consequently the clear aperture, are increased without a corresponding increase in the size of the other prisms (e.g., the blue and green prisms). This is accomplished by adjusting the air gap A2 of the selected light path (e.g., red) so that the effective total selected light path T, which includes the selected light air gap A2 and the selected light glass path G2 is the same as the total path length T of both the other light paths (e.g., green and blue) comprised of air gap A1 plus glass path G1.

Abstract: A color-separating and -recombining optical system includes a cubic- or square column-like first to fourth polarization beam splitters having polarization-splitting planes intersecting each other and wavelength-selective polarizing converters for rotating the plane of polarization of a specific-color light component by 90 degrees. One of the converters is placed at a light-incident side of the first splitter and another is placed at a light-emitting side of the fourth splitter. The first and fourth splitters are provided at a light-incident and light-emitting sides, respectively, of the optical system. The first and fourth splitters are arranged diagonally opposing each other. The remaining converters are placed between at least two inner facing planes of the first to fourth splitters. At least the remaining converters and three of the first to fourth splitters are joined to form an optical joint component with a gap between the component and the remaining one splitter.

Abstract: A color management system for use with projection displays includes, for example, a separating polarizing beamsplitter, a compensating prism group, an image assimilator, and a combining polarizing beam splitter. In accordance with an exemplary embodiment, the separating polarizing beamsplitter receives a bi-oriented light input and separates it into two output beams, one comprising a first component and the other comprising a second component. The image assimilator receives an output light beam from the separating polarizing beamsplitter, transmits the light output to one or more corresponding microdisplays, receives one or more modified outputs from the microdisplays, and emits an output comprising those modified outputs to a combining polarizing beamsplitter.

Abstract: An image display apparatus includes a plurality of light emission sources, a drive circuit for pulse-driving the plurality of light emission sources in order in a predetermined period, a moving reflecting mirror for swinging in order in an incidence direction of light from each of the light emission sources in response to the pulse driving timing of each of the light emission sources and reflecting light beams from the light emission sources in order approximately in the same direction, and a combining optical system for guiding the light reflected by the moving reflecting mirror into a light valve.

Abstract: Removal of unnecessary reflected light in an image display apparatus employing reflective spatial light modulators to enable display of a high-quality image, having good contrast and no occurrence of the ghosting phenomena. Modulated light of each color synthesized by a fourth modulated light beam splitter 16 is injected into a projection lens 19 as circularly polarized light by a ?/4 plate 18, reflected light (R?, G?, B?) reflected from the projection lens 19 does not return to the respective spatial light modulating elements 7, 11 and 12 for each color.

Abstract: A light device has a plurality of light sources, and laser beam sources are arranged near a discharge bulb so that the laser beam can be overlapped with illuminating light from the discharge bulb. By doing so, the illuminating light is irradiated as overlapped illuminating light reinforcing red component, so that color rendering and luminance can be improved.

Abstract: A color separating/recombining unit used in liquid crystal projector using three reflection type liquid crystal panels. The color separating/recombining unit (20) has a cubic form comprising a light incidence surface (21) facing the light source unit (10), three light incidence/output surfaces (23), (24), (25) respectively facing liquid crystal panels (31), (32), (33), a light output surface (22) facing a projection optical system (40), and another surface (26).

Abstract: A reflective projection display system for receiving a light ray and projecting it onto a screen in a light-state mode. The reflective projection display system includes a reflective micro-mirror panel, a projecting device and a prism set. Before reaching the reflective micro-mirror panel, the light ray is firstly reflected by the prism set. The light ray reflected by the reflective micro-mirror panel in the light-state mode directly passes through the prism set and is then received by the projection lens. The light ray reflected by the reflective micro-mirror panel in the dark-state mode is totally reflected at an interface between a prism adjacent to the reflective micro-mirror panel and an air gap adjacent to the prism.

Abstract: A polarized beam splitter includes an inclined intermediate layer between two glass prisms. The intermediate layer includes an adhesive layer and a polarized light separating membrane. The intermediate layer may be wedge-shaped in order to compensate for or to cancel astigmatism of light transmitted by the polarized beam splitter caused by the inclination of the intermediate layer. The polarized beam splitter may also be formed with the refractive indexes of the glass and the adhesive of the adhesive layer chosen to reduce astigmatism. Embodiments of three-color projection image display devices that use the polarized beam splitter are also disclosed. The three-color projection image display devices may use one or three polarized beam splitters with a Philips prism or use two polarized beam splitters with a COLORQUAD.

Abstract: A projection display with a common light source sharing system for improved illumination uniformity is described. The common light source is coupled through a light-dividing prism to multiple integrators. Each integrator is coupled to one or more imaging devices that project image tiles to form a larger composite tiled image.

Abstract: A light pipe for separating incident light according to color, a color illumination system adopting the light pipe, and a projection system adopting the color illumination system are provided. Since the projection system is a single-panel projection system adopting a scrolling unit, its optical configuration is simplified. Also, the light pipe of the projection system is comprised of different-sized color separation units, thus improving the color gamut and the color temperature. Further, the light pipe includes color selection polarizers, each of which changes the polarization direction of a color beam with a specific wavelength, thereby improving light efficiency.

Abstract: The present invention provides a liquid crystal projector including a plurality of liquid crystal panels, a prism for compositing the modulated plural color lights to generate a color image, top and bottom metal plates disposed above and below the prism, and an optical system for magnifying and projecting the generated color image, wherein the liquid crystal panels are directly adhered to metal hold plates, and the metal hold plates are fixed to the top and bottom metal plates such that the emergent surfaces of the liquid crystal panels face the incident surfaces of the prism. Further, a closed space is provided between the incident surfaces of the prism and the emergent surfaces of the liquid crystal panels so as to prevent air contaminants from effecting the performance of the device.

Abstract: A integrating light pipe re-circulates color to improve efficiency. A number of color filters, such as blue, green, and red filters, on the end of the light pipe transmit a selected color and reflect the remaining light back into the light pipe, where it is spatially homogenized and re-circulated back to the output of the light pipe. The re-circulated homogenized light illuminates the filters, and the process repeats. Thus, most of the light from the light source eventually is transmitted through one of the color filters. The filters can provide straight boundaries between the resultant color beams, which are provided to a scrolling element, such as a rotating prism, rotating mirror drum, or linear oscillating optical element, and hence to a light valve. The combination of the re-circulating light pipe and scrolling element provide continuous color scrolling and efficient use of the broad-spectrum light from the light source.

Abstract: A LCD projection system includes a beam splitter that splits a polarized light beam into a light of two primary colors and a light of one primary color, a first polarization element adapted to polarize the light of two primary colors, a second polarization element adapted to polarize the light of one primary color, a dichroic element adapted to separate the two colors of the light of two primary colors, a modulator adapted to modulate the light of tow primary colors and the light of one primary color and to reflect modulated light for output, a retarder provided between the first polarization element and the polarization element, and a projection lens adapted to project modularized light from the modulator and the first polarization element onto a display screen.

Abstract: A projection lens that uses a TIR surface as both an angular filter and fold mirror. A first lens element 602 is placed very close to the TIR prism assembly 604. Because the lens is so close, it gathers both off state and state light from the modulator. Off state light from the DMD follows path 606 while on state light follows path 608. A total internal reflection surface 610 receives both the on state and the off state light. Because the off state light strikes the TIR surface at an angle less than the Brewster's angle, the off state light passes through the TIR prism and is removed from the projection path. The on state light strikes the TIR surface at an angle greater than Brewster's angle and is reflected by the TIR surface through the remaining projection lens components.

Abstract: A compound polarization beam splitter (33) for use with a reflective, polarization-modulating, imaging device (10), e.g., a LCoS device, is provided. The compound PBS has: (a) an input prism (20); (b) an output prism (30), and (c) a polarizer (13), which is located between the two prisms (20,30) and which may be a wire grid polarizer (13a) or a multi-layer reflective polarizer (13b). Polarized illumination light (11) enters the input prism (20) through a first surface (21) and undergoes total internal reflection at a second surface (22) before being reflected from the polarizer (13) and polarization-modulated at the imaging device (10). The polarizer'stilt angle (&bgr;) is less than 45°, which reduces astigmatism and the required back working distance of the system's projection lens (74).

Abstract: A dichroic prism 10 according to the present invention comprises first to fourth right angle prisms 12, 14, 16 and 18 respectively having first side faces 28, 34, 40 and 46, and second side faces 30, 36, 42 and 48, the side faces being arranged perpendicular to each other. A second bonded face 22 and a fourth bonded face 26, each having a dichroic film for a second color light, are arranged on the same plane. The first bonded face 20 and a third bonded face 26, each having the dichroic film for a first color light, are deviated by a predetermined distance. The distance of this deviation is adjusted so that an image formed by the light having reference image information corresponds to the image of the reference image information. The light is made incident on and reflected by the first bonded face and the third bonded face. Therefore, an appropriate image quality can be obtained without depending on a right angle precision.