Abstract: A 2D and 3D image display apparatus including: a display panel forming an image by spatially modulating an input image signal; a polarization conversion device converting a polarization direction of a beam incident into the polarization conversion device according to a voltage applied in synchronization with the image signal; and a switching barrier unit including first polarization units having a first polarization direction and second polarization units having a second polarization direction in an alternate manner, and transmitting the beam passing the polarization conversion device through at least one of the first polarization unit and the second polarization unit. Therefore, a 3D image can be displayed without degrading a horizontal resolution thereof by using a combination of polarization devices with low fabrication costs, which may utilize a time-sequential display method.

Abstract: A projecting system includes a lens for projecting images to a screen, an image generating device for outputting a first image during a first period and a second image during a second period alternately wherein a first polarization angle of the first image is different from a second polarization angle of the second image, an optical control unit for reflecting the first image or the second image transmitted from the image generating device to the lens, a polarizing unit for outputting the first image when rotating to a first angle and for outputting the second image when rotating to a second angle wherein an angular difference between the first angle and the second angle is 90 degrees substantially, and a driving device for driving the polarizing unit to locate at the first angle or at the second angle.

Abstract: An optical projection engine device uses a symmetrical wire grid polarizing beam splitter (PBS) that splits incident illumination to a symmetrical pair of polarized light beams in two orthogonal polarization states, one by reflection and the other by transmission, for illuminating a pair of reflective modulation imagers respectively. In identical geometric configuration, the two synchronized reflective modulation imagers polarization modulate polarized light beams as received, and reflect them back towards the PBS, which through transmission and reflection respectively, combines and projects two modulated light beams through a projection lens system to form a pair of spatially overlapped illumination images of aligned pixels with the same image in two orthogonal polarization states on a projection screen. The device jointly provides improvement optical efficiency and expanded function to three dimensional stereoscopic displays.

Abstract: A stereoscopic image projection system using a circular polarization filter module is provided. Even though this system uses a single projector, it allows left and right images to have different polarization directions using the circular polarization filter module, thereby reducing crosstalk compared to an LCD-shutter-based system.

Abstract: A system and method for projecting stereoscopic images using a multiple projector arrangement is provided. The design comprises transmitting a first field train from the first projector, the first field train comprising first projector left and right images and concurrently transmitting a second field train from the second projector, the second field train comprising second projector left and right images. The first projector left image is transmitted by the first projector at substantially a same time as the second projector right image is transmitted by the second projector. Alternately, the design comprises transmitting a first field train from the first projector, the first field train comprising first projector left images alternating with first projector right images, and concurrently transmitting a second field train from the second projector, the second field train comprising second projector left images alternating with second projector right images. A quasi-interlacing technique is also provided.

Abstract: An autostereoscopic display device comprises a reflection layer for reflecting at least a portion of incident light, a polarization conversion layer arranged over the reflection layer, and an array of lenticular elements arranged over at least a portion of the polarization conversion layer and including a birefringent material. Light having a first state of polarization is arranged to pass through the lenticular element array without substantial lenticular element focusing, wherein the polarization state is transformed by the polarization conversion layer such that the reflected light has a second state of polarization arranged to pass through the lenticular element array with lenticular element focusing to provide multiple views.

Abstract: A 3D image projector having a translucent rotatable hollow cylinder, the hollow cylinder having differently polarized sections, and the projector being capable of passing a light beam generally orthogonally through a wall of the hollow cylinder is disclosed.

Abstract: A digital image projector includes a plurality of light modulation assemblies and a dichroic combiner. Each light modulation assembly includes at least one laser light source configured to provide an illumination beam, an optional a coated surface, and a spatial light modulator. If the coated surface is present, the respective laser light source is configured to direct the illumination beam to the coated surface, which directs the illumination beam toward the respective spatial light modulator. Otherwise, the respective laser light source is configured to direct the illumination beam directly toward the respective spatial light modulator. The spatial light modulator redirects output modulated light back to the coated surface, if present, and out of the corresponding light modulation assembly. The dichroic combiner directs the output modulated light from each of the plurality of light modulation assemblies toward a projection lens for projection onto a display surface.

Abstract: A three dimensional viewing assembly includes a first display, a second display, and a beamsplitter. The first display is for displaying a first image. The second display is for displaying a second image. The beamsplitter is disposed at least partially between the first display and the second display, and is configured to receive, and to optically overlay, the first and second images. The beamsplitter comprises a first surface, a second surface, and a mirror. The first surface at least partially faces the first display, and the second surface at least partially faces the second display. The mirror is disposed between the first surface and the second surface.

Abstract: An image display device includes an illumination system including a light source that emits light; a polarization separating system which polarizes and separates the light emitted from the illumination system; plural color separation systems which are provided in relation to the illumination system, and each of which separates each of lights generated by the polarization separating system into plural basic color lights; plural spatial light modulators which are provided correspondingly to the color separation systems, and each of which light-modulates the plural basic color lights generated by the color separation system respectively according to image signals; plural color synthesizing systems which are provided correspondingly to the color separation systems, and each of which synthesizes the basic color lights modulated by the spatial light modulator; a polarization synthesizing system which synthesizes the lights generated respectively by the plural color synthesizing systems; and a projection system whic

Abstract: An image display device includes a plurality of projection units, each of which having a light source section emitting one of basic-color lights, a spatial light modulation section modulating the basic-color light emitted from the light source section according to an image signal, and a projection system projecting an image based on the basic-color light modulated by the spatial light modulation section onto a screen. The projection units are arranged in an array, and the images, each of which is projected by each of the projection units, are combined on the screen to form a composite image.

Abstract: A digital image projector includes a light assembly configured to project light along a light path from at least one laser array light source, the projected light having an overlapping far field illumination in a far field illumination portion of the light path; a temporally varying optical phase shifting device configured to be in the light path; an optical integrator configured to be in the light path; a spatial light modulator located downstream of the temporally varying optical phase shifting device and the optical integrator in the light path, the spatial light modulator configured to be located in the far field illumination portion of the light path; and projection optics located downstream of the spatial light modulator in the light path, the projection optics configured to direct substantially speckle free light from the spatial light modulator toward a display surface.

Abstract: A projection-type 3-D image display includes a light source, a single display element, an image shift member, a projection lens unit, and a screen unit. The display element produces an image using light emitted from the light source. The image shift member time-sequentially shifts the image. The projection lens unit enlarges and projects the time sequentially shifted image. The screen unit includes an image separation unit. The image separation unit separates the time sequentially shifted image into images for a left eye and images for a right eye. The projection-type 3-D image display can realize a 3-D image using a single projector by having the image shift member to sequentially shift the images produced by the display element.

Abstract: A stereoscopic digital image projector includes (a) a plurality of light modulation assemblies, each comprising: (i) at least one solid-state light source energizable to provide illumination having a first polarization axis; (ii) a polarization rotator disposed in the path of the polarized illumination from the solid-state light source(s) and actuable to controllably rotate the polarization axis from the solid-state light source(s) to a second polarized axis; (iii) a micro-electromechanical spatial light modulator in the path of the polarized illumination and energizable to modulate the polarized illumination to form a first modulated light from illumination of the first polarization state and to form a second modulated light from illumination of the second polarization state; and (b) a synchronizing means to temporally control the polarization rotation to match the appropriate image data on the spatial light modulator; and (c) projection optics for directing the first and second modulated light toward a disp

Abstract: The present invention provides a projection-type three-dimensional image reproducing apparatus that enables stable provision of a three-dimensional image display by preventing occurrence of crosstalk between adjacent lenses or adjacent hologram optical elements and eliminating shift of a three-dimensional image when a steroscopic image is reproduced by use of a lenticular lens array, a fly-eye lens array, or a hologram optical element. The three-dimension image reproduce apparatus includes an array of adjoining optical elements, which is an array of lenticular lens, a fly-eye lens array or an array of hologram optical elements, and a cross-talk prevent part preventing cross-talk between the adjoining optical elements.

Abstract: A digital image projector includes a first polarized light source; a second polarized light source that is orthogonal in polarization state to the first polarized light source; a polarization beamsplitter disposed to direct light of either the first or second polarization along a common illumination axis; a MEMS spatial light modulator; and projection optics for delivering imaging light from the MEMS spatial light modulator.

Abstract: A polarization conversion system separates light from an unpolarized image source into a first state of polarization (SOP) and an orthogonal second SOP, and directs the polarized light on first and second light paths. The SOP of light on only one of the light paths is transformed to an orthogonal state such that both light paths have the same SOP. A polarization modulator temporally modulates the light on the first and second light paths to first and second output states of polarization. First and second projection lenses direct light on the first and second light paths toward a projection screen to form substantially overlapping polarization encoded images. The polarization modulator may be located before or after the projection lenses. The polarization-encoded images may be viewed using eyewear with appropriate polarization filters.

Abstract: In the specification and drawing, a stereoscopic image display apparatus is described and shown with eyewear having a polarization interference filter, wherein the polarization interference filter can distinguish both polarization and spectra.

Abstract: A stereo projection optical system includes an image assimilator and a transmission-type light modulator positioned to receive the emergent light of the image assimilator. The image assimilator is configured for superimposing spatial information on the incident light beam and emitting one of a first polarized light component and a second polarized light component. The transmission-type light modulator alternates between a dark state and a bright state. The stereo projection optical systems provide viewers three-dimensional images formed by two alternative polarized lights whose polarizations are perpendicular relative to each other utilizing the transmission-type light modulators.

Abstract: A stereo projection optical system includes a polarizing beam splitter, a 2-way wheel, a digital micro-mirror device, and a total internal reflection prism. The polarizing beam splitter is configured for emitting two light outputs. The 2-way wheel includes a reflective region and a transmissive region. The reflective region is configured for reflecting the light outputs and the transmissive region is configured for transmitting the light outputs. The digital micro-mirror device is configured for superimposing spatial information on the light outputs. The total internal reflection prism configured for coupling the light outputs of the 2-way wheel into the digital micro-mirror device and transmitting a light output of the digital micro-mirror device. The stereo projection optical systems provide viewers three-dimensional images formed by two alternative polarized light beams whose polarizations are perpendicular to each other utilizing the 2-way wheel.

Abstract: A stereo projection optical system includes a polarization converter, a 2-way wheel, a retarder, and an image engine. The polarization converter is configured for converting an incident light into a polarized light which have single polarization. The 2-way wheel includes a reflective region and a transmissive region. The reflective region is configured for reflecting the polarized light and the transmissive region is configured for transmitting the polarized light. The retarder is positioned to receive an emergent light from one of the reflective region and the transmissive region. The image engine is positioned to receive light output of the 2-way wheel and the retarder and configured for emitting the light output comprising spatial information. The stereo projection optical systems provide viewers three-dimensional images formed by two alternative polarized light beams whose polarizations are perpendicular to each other utilizing the 2-way wheel.

Abstract: A stereo projection optical system includes a polarizing beam splitter configured for splitting a light input into first, second polarized light components, first, second digital micro-mirror device respectively positioned to receive the first, second polarized light component and configured for superimposing spatial information on the first, second polarized light component, first, second total internal reflection prism configured for coupling the first, second polarized light component into the first, second digital micro-mirror device and a light combiner. The projecting lens projects two images formed by the first polarized light component and the second polarized light component with spatial information in the stereo projection optical systems. When a viewer wear glasses that have two polarizing lenses whose polarization direction is perpendicular to each other, the viewer can perceive projected images as being “3-D”.

Abstract: Lighting devices are disclosed that include optical laminated bodies. An exemplary optical laminated body includes a polarizing layer, a first transparent film disposed closely to a front surface of the polarizing layer and a second transparent film disposed closely to a back surface of the polarizing layer. The polarizing layer includes a reflective polarizing film, and both of the first transparent film and the second transparent film are diffusive films. The lighting devices further include a light source supplying light to the optical laminated body through a light entry surface of the first transparent film of the optical laminated body, wherein the light source includes a plurality of diffusing points of a light diffusive substance disposed on a surface of the light source. The lighting device provides diffused-polarized light emitted from a light emitting surface of the second transparent film of the laminated body.

Abstract: An image projection system having an optical projector and a method for projecting an image. The image projection system enables viewing the images in three dimensions and securely viewing the images in a public forum. The image projection system may include a portable, handheld optical projector that is spaced apart from a display screen and that redirects an image signal to the display screen. The image signal is scattered by the display screen and transmitted to a viewer's eyes through a set of eyewear worn by the viewer. The display screen preserves the polarization state of the image signal. The portable handheld optical projector may be a cellular phone, a personal digital assistant, a portable computer, or the like that includes one or more sets of light emission systems capable of projecting the image signal. The optical projector may be portable and handheld, or stationary or semi-stationary.

Abstract: A stereo projection optical system includes a first polarizing beam splitter, a transmission-type light modulator positioned to receive the first polarized light component from the first polarizing light splitter and an image assimilator positioned to receive an emergent light of the transmission-type light modulator. The image assimilator includes a second polarized light splitter and first, second reflective spatial light modulators. The stereo projection optical systems provide viewers three-dimensional images formed by two alternative polarization light beams whose polarizations are perpendicular to each other utilizing the transmission-type light modulators to form “3-D” images.

Abstract: A stereo projection optical system, includes a first polarizing beam splitter configured for separating a light input into a first polarized light component and a second polarized light component; a first image assimilator positioned to receive the first polarized light component; a first image assimilator positioned to receive the second polarized light component; a fourth polarizing beam splitter positioned to receive the light outputs of the first, second image assimilators. The first, second image assimilators to project two images formed by the first polarized light component and the second polarized light component with spatial information in the stereo projection optical systems. When viewers wear glasses that have two polarizing lenses whose polarization directions are perpendicular to each other, the viewers can perceive projected images as three-dimension.

Abstract: A stereoscopic display for switching between a 2D image and a 3D image, including a display device displaying an image; and a parallax barrier that transmits incident light in a 2D mode and forms barriers to separate images for a left eye and a right eye in a 3D mode. The parallax barrier unit includes a first polarization plate transmitting light with a first polarization direction; a 2D first polarization grating screen including a first birefringence element and a second birefringence element alternating with each other in a grating pattern; a 2D second polarization grating screen facing the first polarization grating screen and including a third birefringence element and a fourth birefringence element alternating with each other in a grating pattern; and a second polarization plate facing the second polarization grating screen and transmitting only light with a second polarization direction among lights transmitted through the second polarization grating screen.

Abstract: Provided is a projection type stereoscopic display apparatus that can separately display far images and near images. The projection type stereoscopic display apparatus includes: a projector projecting a near image with first polarized light and a far image with second polarized light, which is different from the first polarized light of the near image, in a direction in which a viewer observes the near and far images; a front screen facing the projector, and allowing the near image with the first polarized light to be formed thereon and the far image with the second polarized light to be transmitted therethrough; and a rear screen spaced a predetermined distance apart from a rear surface of the front screen, and allowing the far image with the second polarized light transmitted through the front screen to be formed thereon, wherein the viewer positioned in front of the screen can simultaneously see the near image and the far image respectively formed on the front screen and the rear screen.

Abstract: A method and apparatus are provided to provide a laser projection display (LPD).

Abstract: The invention relates to an autostereoscopic projection arrangement, comprising at least one projector (4) and at least one filter array (F1, F2), which has a multitude of filter elements arranged in columns and rows, in which arrangement bits of partial information from views of a scene or object are projected by the projector/the projectors (4) onto a projection screen (3), where these bits of partial information are rendered on image rendering elements and, having passed one or several of the filter arrays (F1, F2), are made visible to at least one observer (5), and in which, as regards the propagation direction of the bits of partial information, the image rendering elements correspond with correlated filter elements in such a way that an observer (5) will see predominantly bits of partial information from a first selection of views with one eye and predominantly bits of partial information from a second selection of views with the other eye, and thus will have a spatial impression.

Abstract: An autostereoscopic projection arrangement, comprising at least one projector and at least one filter array which has a multitude of filter elements arranged in columns and rows, in which arrangement bits of partial information from views of a scene or object are projected by the projector(s) onto a projection screen, where there bits of partial information are rendered on image rendering elements and, having passed one or several of the filter arrays, are made visible to at least one observer, and in which, as regards to propagation direction of the bits of partial information, the image rendering elements correspond with correlated filter elements in such a way that an observer will see predominantly bits of partial information from a first selection of views with one eye and predominantly bits of partial information from a second selection of views with the other eye, and thus will have a spatial impression.

Abstract: An image-combining device comprising of a polarizing beam-splitter, two waveplates and two reflective micro-electro-mechanical display panels is described. It combines images with orthogonally polarized light. Projection display apparatus having such image-combining device(s) are used to project two-dimensional or three-dimensional images with orthogonally polarized light.

Abstract: An autostereoscopic display having an improved 2D/3D mode switchable structure, including a display device to display an image, and a parallax barrier unit to transmit all incident light in a 2D mode and to separate a left-eye image and a right-eye image by forming a barrier in a 3D mode. The parallax barrier unit includes a polarizer to transmit light having a predetermined polarizer polarization direction, a first plane array including first and second birefringent elements, which change a polarization direction of light transmitted through the polarizer into a first direction and a second direction opposite to the first direction, respectively, and a second plane array including third and fourth birefringent elements, which change a polarization direction of light transmitted through the first plane array into a third direction and a fourth direction, that is opposite from the third direction, respectively.

Abstract: A display system in which images from two displays that have the same optical polarization that is not affected by reflection by a beam splitter which combines images from the displays, and half wave plate optical retarders to rotate plane of polarization and to null out optical dispersion effects to provide for stereo viewing of images via plane polarizers that have the same polarization direction.

Abstract: A multiple path stereoscopic projection system is disclosed. The system comprises a polarizing splitting element configured to receive image light energy and split the image light energy received into a primary path and a secondary path, a reflector in the secondary path, and a polarization modulator or polarization modulator arrangement positioned in the primary path and configured to modulate the primary path of light energy. A polarization modulator may be included within the secondary path, a retarder may be used, and optional devices that may be successfully employed in the system include elements to substantially optically superimpose light energy transmission between paths and cleanup polarizers. The projection system can enhance the brightness of stereoscopic images perceived by a viewer. Static polarizer dual projection implementations free of polarization modulators are also provided.

Abstract: In one embodiment, a system for generating stereo images includes a front display adapted to project a polarized first image along a viewing axis, a back display adapted to project a polarized second image along the viewing axis and through the front display, and a controller coupled to at least the front display and adapted to oscillate image projection between the front display and back display. The system in this embodiment further includes a first lens portion and a second lens portion, the first lens portion being polarized to the same state as the front display and the second lens portion being polarized to the same state as the back display.

Abstract: A rear projection display device improves the brightness by improving the utilization efficiency of image light projected to a screen from slantly below. At least a green component of the image light is P-polarized to the screen (7). Therefore, reflection of light on the screen (7) is reduced.

Abstract: A three dimensional display system 100 using two spatial light modulators and a single projection path. Light source 102 emits a white light beam 104 which typically is focused onto an aperture of a recycling integrator 106. The light beam travels through the recycling integrator 106 and is reflected several times by the walls of the integrator 106. The sequential color filter creates a filtered light beam comprised of at least three spatially separated light beams. The filtered light beam, containing the colored filtered sub-beams, is separated by a polarizing beam splitter 116 into two separate light beams, each comprising a portion of each color sub-beam created by the sequential color filter. A first portion of the light beam having a first polarization state is passed to a first spatial light modulator 112. A second portion of the light beam having a second polarization state is reflected to a second spatial light modulator 114.

Abstract: A rear projection display device improves the brightness by improving the utilization efficiency of image light projected to a screen from slantly below. At least a green component of the image light is P-polarized to the screen (7). Therefore, reflection of light on the screen (7) is reduced.

Abstract: Methods and apparatus for forming two orthogonally polarized beams of light from an unpolarized beam of light using one of at least two different image modes, the forming includes a color filtering process that is based on the image mode being used, and projecting the two orthogonally polarized beams to form an image on a viewing surface. Methods and apparatus for separating an unpolarized light beam into four beams as a function of wavelength and polarization; selectively modulating the four beams respectively using four light valves; and combining the four modulated beams to generate two orthogonally polarized light beams.

Abstract: An autostereoscopic projection screen with projection displays a stereoscopic image for receiving parallax images of right eye and left eye. The autostereoscopic projection screen includes a polarization-reserved diffuser, a microretarder, a polarizer, and a parallax element. Parallax images of right eye and left eye pass through the polarization-reserved diffuser and the microretarder for transferring their polarization states. Parallax images of right eye and left eye with specific polarization states will pass the polarizer and parallax element for dividing images of right eye and left eye from parallax images. The individual images separately enter viewing zones of right eye and left eye to generate the stereoscopic-image for viewers.

Abstract: Provided are several apparatus and methods to attenuate illumination light in a projector. Illumination light may be attenuated by directing polarized light toward a liquid crystal (LC) attenuation panel. The panel selectively modulates some, all, or none of the polarized light passing through. The light from the panel is then directed toward a polarization device. The polarization device analyzes the polarized light, and allows or denies the light to pass therethrough based on the polarization of the light.

Abstract: An autostereoscopic optical apparatus (10) for viewing a stereoscopic image comprising a left image to be viewed by an observer (12) at a left viewing pupil (14l) and a right image to be viewed by the observer at a right viewing pupil (14r). A left image generation system (70l) forms a left curved intermediate image near the focal surface (22) of a curved mirror (24). A right image generation system (70r) forms a right intermediate image near the focal surface of the curved mirror. A center of curvature of the curved mirror is placed substantially optically midway between the exit pupil and the left optical system (110l) the exit pupil of the right optical system (110r). A beamsplitter is disposed between the focal surface and the center of curvature of the curved mirror.

Abstract: A stereoscopic projection system is provided having two channels, each having two LCOS imagers that modulate light on a pixel-by pixel basis. A first polarizing beam splitter is configured to direct light of a first polarization onto a first channel first stage LCOS imager and direct light of a second polarization, opposite the first polarization, onto a second channel first stage LCOS imager. A relay lens system directs the output of the first stage imagers into a second polarizing beam splitter. The second polarizing beam splitter is configured to direct light of the second polarization onto the first channel second stage LCOS imager and direct light of the first polarization onto the second channel second stage LCOS imager.

Abstract: A liquid crystal display apparatus including: a liquid crystal display element having a liquid crystal layer between a couple of substrates; a backlight apparatus arranged at one side of the couple of substrates; a polarizer arranged between the liquid crystal display element and the backlight apparatus; a luminous intensity distribution control element arranged at the other side of the couple of substrates; an analyzer arranged between the liquid crystal display element and the luminous intensity distribution control element, wherein the luminous intensity distribution control element comprises a transparent base member, a plural lenses arranged on the transparent base member, and a light absorbing layer having small opening portions substantially at focal positions of an individual lens of the plural lenses, and the transparent base member is constituted of a transparent body substantially optically isotropic or a transparent body having uniaxial optical anisotropy.

Abstract: An improved autostereoscopic display apparatus (10) forms left and right virtual images for pupil imaging by forming, through a beamsplitter (16), a real intermediate image near the focal surface of a curved mirror (24). A circular polarizer (90) is disposed at a position between viewing pupils (14l, 14r) and the beamsplitter (16), minimizing glare due to stray light reflection from the curved mirror surface.

Abstract: A flat-panel projection display comprises a slab waveguide having a preferably embossed diffraction grating on one face, a lens for directing light into an edge of the waveguide, and in the focal plane of the lens a liquid-crystal modulator for modulating the intensity of the light as a function of lateral position and elevational direction of travel. The light is ejected from the slab waveguide by the grating at angles corresponding to the input angles, giving a virtual display. The light from the modulator can be expanded in one dimension by passing through a magnifying waveguide, followed by scattering in the plane by a screen and projection by a lens at the other end of the waveguide. Head-up and 3-D displays can be constructed using this principle.

Abstract: This invention relates to electromagnetic wave beam paths, formation of the beam, illumination of programmable electromagnetic wave field vector orientation rotating devices (“PEMFVORD”) with an electromagnetic beam, and the technique of projection of the modulated beam. This invention also relates to a unique light path and method of forming the light into a rectangular beam to be used for optical projection systems and, more particularly, in a color and/or black and white liquid crystal device (LCD) projectors that produce high resolution, high brightness and/or three-dimensional images. This invention further relates to a device capable of receiving and displaying two-dimensional and three dimensional images.

Abstract: A light direction switching apparatus and method is described. The light direction switching apparatus comprises a passive birefringent lens (138), e.g. a birefringent lenticular screen, and a switchable polariser (146). By switching the polariser (146), different directional distributions of output light are provided. The light direction switching apparatus may be used with or incorporated in a display device, such as a liquid crystal display device, to provide a display device switchable between a two dimensional mode and an autostereoscopic three dimensional mode, or to provide a multi-user display device where different images are displayed to different viewers. The light direction switching apparatus may also be used to provide switchable brightness enhancement of reflective or transflective display devices. The light direction switching apparatus may also be used to provide a fiber-optic switching apparatus. The switchable polariser may be mechanically switchable or electrically switchable.

Abstract: In order to provide a liquid crystal projector that prevents the image burn-in phenomenon or image sticking in a liquid crystal projector of ferroelectric liquid crystal, and moreover, that provides a bright projected image, the polarization directions of linearly polarized light beams that are irradiated upon a liquid crystal display device are switched in synchronization with the alternate reversal of the polarity of the liquid crystal display device, whereby a negative image, which could not be displayed in the prior art, can be converted to a positive image and displayed.