Abstract: An illumination system includes first and second red light sources, first and second green light sources, first and second blue light sources, and a first light-splitting device. The first red light source, the first green light source, and the first blue light source respectively provide a first red light beam, a first green light beam, and a first blue light beam with a first polarization state. The second red light source, the second green light source, and the second blue light source respectively provide a second red light beam, a second green light beam, and a second blue light beam with a second polarization state. The first light-splitting device is disposed on transmission paths of the first and second red light beams, the first and second green light beams, and the first and second blue light beams to form an illumination beam.

Abstract: A projector includes an image light generator configured to modulate light emitted from a light source to generate image light, a projection optical device configured to project the image light, a polarization switching element disposed at a light exit side of the image light generator and configured to switch a polarization state of the image light emitted from the image light generator, and a controller configured to control the polarization switching element. The controller controls the polarization switching element to switch the polarization state of the image light with a predetermined period.

Abstract: An eyewear lens is described that provides polarization filtering and spectral filtering using polarization interference. The lens produces enhanced saturation and colorfulness, increasing enjoyment when observing commonly encountered imagery. The lens can be configured to optimize accuracy/efficiency when performing a task involving colored imagery, and can improve performance in sports. The lens can further be helpful for color discrimination by those with certain types of color vision deficiency.

Abstract: A stereoscopic image display apparatus that is capable of being efficiently aligned using a remotely controlled alignment function and a method of displaying a stereoscopic image using the same are disclosed.

Abstract: The backlight module includes multiple backlight units. Each backlight unit includes a first light emitting unit and multiple second light emitting units. The first light emitting unit has a first beam angle, and each second light emitting unit has a second beam angle which is narrower than the first beam angle. In a first mode, a light intensity of the first light emitting unit is equal to a first intensity, and a light intensity of the second light emitting units is equal to a second intensity. In a second mode, the light intensity of the first light emitting unit is equal to a third intensity, and the light intensity of the second light emitting units is equal to a fourth intensity. The first intensity is greater than the third intensity, and the second intensity is less than the fourth intensity.

Abstract: A stereoscopic image apparatus that is capable of minimizing loss of optical energy and improving quality of a stereoscopic image is disclosed. The stereoscopic image apparatus includes a polarizing beam splitter to reflect or transmit incident light based on polarization components of the light to split the light in at least three different directions, a reflective member to reflect the light reflected by the polarizing beam splitter to a screen, at least one modulator to modulate the light reflected by the reflective member and the light transmitted through the polarizing beam splitter, and a refractive member disposed in an advancing direction of light to be incident upon the polarizing beam splitter to refract the light to be incident upon the polarizing beam splitter.

Abstract: Systems and methods for providing a polarization recycling structure for use in applications, such as display systems that include a liquid crystal display assembly. The polarization recycling structure may include a first spatially varying polarizer spaced apart from a second spatially varying polarizer. The first spatially varying polarizer may include a lens array that receives light from a light source and focuses light of a first polarization state and passes light of a second polarization state. The second spatially varying polarizer receive light from the first spatially varying polarizer, passes the focused light of the first polarization state, and transforms the light of the second polarization state into the first polarization state, thereby providing only light of the first polarization state at the output of the polarization recycling structure.

Abstract: An example optical system for a 3D stereoscopic image display comprises a changing mirror, a rotating mirror, a tilted mirror, a concave mirror and a planar mirror. The changing mirror can change the path of light from a horizontal direction to a vertical direction. The rotating mirror can rotate while having an X-axis and a Y-axis with different curvature radii. The tilted mirror can include a central region with a hole for allowing light to pass therethrough, and a peripheral region having one surface having a concave tilted structure while the other surface has a planar structure. The concave mirror can include a central region with a hole having a size capable of encompassing the tilted mirror and a peripheral region having a bent structure that is completely concave. The planar mirror can include a central region with a hole and a peripheral region with a flat doughnut structure.

Abstract: A laser mixing module includes first, second, and third laser sets and a condensing lens. The first laser set includes first and second laser sources and a first polarization beam splitter reflecting a polarization light of the first laser source and allowing a polarization light of the second laser source to pass for forming a first laser beam. The second laser set includes third and fourth laser sources and a second polarization beam splitter reflecting a polarization light of the third laser source and allowing a polarization light of the fourth laser source to pass therethrough for forming a second laser beam. The third laser set includes a fifth laser source and first and second dichroic mirrors respectively reflecting the first and second laser beams and allowing a light of the fifth laser source to pass for forming a third laser beam. The condensing lens condenses the third laser beam.

Abstract: A projection device for providing an image light includes a light source module configured to provide an illumination light, a dichroic film configured to allow a first portion of the illumination light to transmit therethrough to form a light in a first wavelength range and to reflect a second portion of the illumination light into a light in a second wavelength range different from the first wavelength range, a first digital micromirror device (DMD) configured to reflect the light in the first wavelength range from the dichroic film into a first light, and a second DMD configured to reflect the light in the second wavelength range from the dichroic film into a second light, wherein the first light and the second light together form the image light.

Abstract: Systems and methods for providing a display for an electronic device that includes a liquid crystal display panel assembly, a backlight assembly that includes a light source, and a spatially varying polarizer that provides phase retardation that varies as a function of propagation length away from the light source. The display may also include a linear polarizer and other optical components that improve the efficiency of the backlight assembly, thereby reducing power consumption, cost, space requirements, and provide other advantages.

Abstract: A near-eye display device and a near-eye display method for human eye of an observer are provided in embodiments of the disclosure, the near-eye display device including: a light source device, configured to emit a plurality of single-colored light beams sequentially; a light guide device, on a light-emergent side of the light source device, and configured to receive and transmit the plurality of single-colored light beams from the light source device and to guide the plurality of single-colored light beams to emit outwards from a light-emergent side of the light guide device; a display panel, on the light-emergent side of the light guide device and comprising a plurality of pixels, and configured to receive the plurality of single-colored light beams from the light guide device and to control both color and grayscale of emergent light beams generated by the plurality of snide-colored light beams which are incident on the display panel and transmitted through the plurality of pixels, and then exit the display

Abstract: A polarization rotation device including a rotation shaft, a driving element, a polarization element and a reflective element is provided. The polarization element is disposed on a transmission path of the at least one excitation light beam. The reflective element is disposed on a side of the polarization element. The driving element drives the polarization element to sequentially rotate with the rotation shaft as a rotation center axis. When the polarization element rotates, the excitation light beam is transmitted to the polarization element and passes through the polarization element and is again transmitted to and passes through the polarization element by the reflective element. The excitation light beam outputting from the polarization rotation device has different polarization states at different time periods. A projection device applying the polarization rotation device of the invention achieves the effect of uniform color or brightness when displaying images in a 3D display mode.

Abstract: A stereoscopic image apparatus that is capable of minimizing loss of optical energy and improving quality of a stereoscopic image is disclosed. The stereoscopic image apparatus includes a polarizing beam splitter to reflect or transmit incident light based on polarization components of the light to split the light in at least three different directions, a reflective member to reflect the light reflected by the polarizing beam splitter to a screen, at least one modulator to modulate the light reflected by the reflective member and the light transmitted through the polarizing beam splitter, and a refractive member disposed in an advancing direction of light to be incident upon the polarizing beam splitter to refract the light to be incident upon the polarizing beam splitter.

Abstract: A method includes capturing an image of a lenticular display, generating a lenticular distortion map of the lenticular display using the image, and compensating for a lenticular distortion of the lenticular display using the lenticular distortion map. The lenticular distortion map is a dual-component lenticular distortion map and the image is a fringe pattern. The method compensates for the lenticular distortion by adjusting a swizzle function based on the lenticular distortion map.

Abstract: A photoelectronic sensor or the like capable of improving operation stability is provided. The photoelectronic sensor includes a light projecting unit having a light projecting lens that converges light and a light projecting element that projects light toward a reflective plate via the light projecting lens, and a light receiving unit disposed alongside the light projecting unit and having a light receiving lens that concentrates reflected light from the reflective plate and a light receiving element that receives the reflected light via the light receiving lens. The light projecting element has a light emitting area located on a side closer to the light receiving element than an optical axis of the light projecting lens and emitting light, and a non-light emitting area located on a side farther from the light receiving element than the optical axis and not emitting light.

Abstract: An out-of-field rejection filter (OFRF) can be used in optical systems to reject stray light. Such optical systems can include cameras, projectors, star trackers, and virtual reality or augmented reality displays. The OFRF can include a converter to convert randomly polarized light to p-polarized light and an angular selectivity layer to select in-field p-polarized light and reject out-of-field p-polarized light. The converter and the angular selectivity layer are configured so as to filter out-of-field light while passing in-field light within a light bandwidth. The angular selectivity layer can be a multilayer film of interleaved materials having alternating permittivity and magnetic permeability properties.

Abstract: Devices, systems, and methods corresponding to addressing misalignment in display systems are provided. A method includes using a first microelectromechanical system (MEMS) mirror, directing a first signal from a first light source to an alignment tracking waveguide. The method further includes receiving by a first photosensor a first portion of the first signal via the alignment tracking waveguide and determining a first alignment indicator associated with the first portion of the first signal. The method further includes using a second MEMS mirror, directing a second signal from a second light source to the alignment tracking waveguide. The method further includes receiving by a second photosensor a second portion of the second signal via the alignment tracking waveguide and determining a second alignment indicator associated with the second portion of the second signal.

Abstract: There is provided a system and method for providing privacy viewing of an output from a electronic display, including a first polarizer configured to polarize a display signal at a first polarization angle; a second polarizer configured to polarize a noise signal at a second polarization angle orthogonal to the first polarization angle; a combiner configured to combine the polarized display signal and the polarized noise signal, and a third polarizer configured to receive the output of the electronic display and polarize the combined polarized display and noise signal at the first polarization angle. The system includes first and second polarization rotators configured to rotate the first and second polarization angles of the combined polarized display and noise signals prior to being output by the electronic display and prior to being received by the third polarizer.

Abstract: In some embodiments, a polarizing beam splitter is provided. The beam splitter may comprise an optically transmissive spacer having first and second opposing faces, with a first polarizer on the first opposing face and a second polarizer on the second opposing face. The optically transmissive spacer may separate first and second triangular prisms of a cube-type beam splitter, with the first polarizer between the first triangular prism and the first opposing face of the spacer, and the second polarizer between the second triangular prism and the second opposing face of the spacer.

Abstract: The present invention provides the first practical stereoscopic 3-D television/computer solution for home consumers. Taking advantage of the way the human brain processes imagery, a new compression algorithm, utilizing a new concept called “shared pixel parts”, allows for the transmission, reception, and display of full HD stereoscopic 3-D video with no loss of resolution or frames to either eye, using a single conventional TV channel and any type of conventional display without alteration. Depending on the type of display used, viewers wear either passive polarized glasses, a new type of static colored filter glasses, or a new type of active colored filter glasses to view the same data signal showing virtually ghost-free full-color images with great depth, a wide angle of view, and a bright flickerless image which doesn't produce any discomfort even after extended viewing, and the signal is also compatible with current 3-D-ready TVs.

Abstract: The present invention relates to a stereoscopic image device and a method for providing a stereoscopic image and, more specifically, to a stereoscopic image device and a method capable of providing a stereoscopic image, which can provide high-quality stereoscopic image by using two projectors and devices related thereto.

Abstract: The prevent invention provides a lens focusing apparatus. The lens focusing apparatus comprises a lens holding module for clamping at least one lens to be tested, a chart display module and a focal length shortening module. The chart display module includes a frame assembly, a first chart display and a plurality of second chart displays disposed on the frame assembly. Each second chart display is inclined at a first predetermined angle relative to the first chart display. The focal length shortening module includes a first focal length shortening device and a plurality of second focal length shortening devices. The first focal length shortening device is disposed between the at least one lens and the first chart display, and each second focal length shortening device is disposed between the at least one lens and the corresponding second chart display.

Abstract: Provided are display apparatuses and electronic apparatuses that include the display apparatuses. The display apparatus may include an optical system that transfers a first image and a second image to an ocular organ of a user. The optical system may include at least two polarization-dependent lenses. Each of the two polarization-dependent lenses may have a focal length that varies based on a polarization state of incident light. The two polarization-dependent lenses may have optically different characteristics with respect to the first and second images. The display apparatus may further include at least one wave plate and/or at least one polarizer provided between the two polarization-dependent lenses or outside thereof.

Abstract: The present invention discloses a stereoscopic 3d projection system that is based on elliptical polarization, and more specifically a time-multiplexed stereoscopic 3d projection system that enables the viewer to observe stereoscopic 3d images on the surface of a polarization-preserving projection-screen via utilization of passive elliptically-polarized viewing-glasses. The disclosed invention provides a stereoscopic 3d projection system that is capable of operating at higher frame-rates and/or with higher optical light efficiency as compared to other prior-art technologies that are instead based on circular polarization.

Abstract: There is provided a system and method for providing privacy viewing of an output from a electronic display, including a first polarizer configured to polarize a display signal at a first polarization angle; a second polarizer configured to polarize a noise signal at a second polarization angle orthogonal to the first polarization angle; a combiner configured to combine the polarized display signal and the polarized noise signal, and a third polarizer configured to receive the output of the electronic display and polarize the combined polarized display and noise signal at the first polarization angle. The system includes first and second polarization rotators configured to rotate the first and second polarization angles of the combined polarized display and noise signals prior to being output by the electronic display and prior to being received by the third polarizer.

Abstract: A stereoscopic image display apparatus that is capable of being efficiently aligned using a remotely controlled alignment function and a method of displaying a stereoscopic image using the same are disclosed.

Abstract: A method and system are provided for enhancing vision. The method includes capturing a first image by a first camera. The method further includes capturing a second image by a second camera. The method also includes combining the first image and the second image to form a combined image. The method additionally includes projecting the combined image on at least one eye of a user by a wearable image projection device. The combined image represents a wide screen image having a field of view greater than any of the first image and the second image taken individually.

Abstract: Shaped glasses have curved surface lenses and spectrally complementary filters disposed on the curved surface lenses configured to compensate for wavelength shifts occurring due to viewing angles and other sources. The spectrally complementary filters include guard bands to prevent crosstalk between spectrally complementary portions of a 3D image viewed through the shaped glasses. In one embodiment, the spectrally complementary filters are disposed on the curved lenses with increasing layer thickness towards edges of the lenses. The projected complementary images may also be pre-shifted to compensate for subsequent wavelength shifts occurring while viewing the images.

Abstract: A display system comprises a projector combined with a retro reflective screen and a viewer distance from the projector such that the observation angle is less than approximately 2-3 degrees. The brightness of the image on the screen for the proposed display system is increased by a factor of ˜100-500× as compared to traditional display systems with for an equivalent power/intensity light source.

Abstract: There is provided a system and method for providing privacy viewing of an output from a electronic display, including a first polarizer configured to polarize a display signal at a first polarization angle; a second polarizer configured to polarize a noise signal at a second polarization angle orthogonal to the first polarization angle; a combiner configured to combine the polarized display signal and the polarized noise signal, and a third polarizer configured to receive the output of the electronic display and polarize the combined polarized display and noise signal at the first polarization angle. The system includes first and second polarization rotators configured to rotate the first and second polarization angles of the combined polarized display and noise signals prior to being output by the electronic display and prior to being received by the third polarizer.

Abstract: A display processing apparatus is configured to process linearly polarized light emitted out from a display device.

Abstract: The invention relates to the field of optoelectronics and display technology and can be used in high speed stereoscopic glasses when working with any type of 3D display, designed to operate with active stereo glasses with standard (60-160 Hz), high (hundreds of Hz) and ultrahigh (several kilohertz) frame rate. According to the invention in optical shutters of high-speed stereo glasses a layer of the helix-free ferroelectric liquid crystal (FLC) with optimized physical parameters is used. The technical result is an increase of the optical contrast of FLC shutters, reducing the amplitude of the control voltage.

Abstract: An autostereoscopic projection device includes an illuminating module, a light modulator, an optical module, and a lens module. The illuminating module is for providing light beams having different deflection angles in sequence. The light modulator is for modulating the light beams into compound images in sequence. The optical module is for guiding the light beams provided by the illuminating module to the light modulator, and guiding the compound images to the lens module. The lens module includes a beam splitting prism group, a first spatial filter, a second spatial filter, and a lens. The optical module is disposed at the incident surface of the beam splitting prism group. The first and second spatial filters are disposed at the first and second relay surfaces of beam splitting prism group for filtering the compound images to first and second images in sequence. The second images are different from the first images.

Abstract: Disclosed embodiments include stereoscopic systems having at least one compensator operable to reduce the sensitivity of polarization control over incidence angle of image source optics and analyzer optics. In an exemplary embodiment, the disclosed compensator is operable to compensate polarization changes induced by optics at either or both the image source subsystem and the analyzer subsystem, in which the polarization changes would be operable to cause leakage at the analyzer subsystem if uncompensated. As such, the disclosed compensators and compensation techniques are operable to reduce leakage at the analyzer subsystem even if the disclosed compensator may be located at the analyzer subsystem.

Abstract: A compression algorithm, utilizing a new concept called “shared pixel parts”, allows for transmitting, receiving, and displaying full HD stereoscopic 3-D video with no loss of resolution or frames to either eye, using a single conventional TV channel and any type of conventional display without alteration. Depending on the type of display, viewers wear either passive polarized glasses, a new type of static colored-filter glasses, or a new type of active colored-filter glasses to view the same data signal showing virtually ghost-free full-color images with great depth, a wide angle of view, and a bright flickerless image which doesn't produce any discomfort even after extended viewing. The signal is also compatible with current 3-D-ready TVs. The compression algorithm can also be used to transmit and display a 2-D image with double the resolution of the display being used for viewing, with no increase of required transmission bandwidth.

Abstract: Disclosed embodiments relate to a stereoscopic projection system and methods. An exemplary disclosed projection system includes an optical component disposed between the lenses of a lens arrangement. An exemplary lens arrangement includes a first power group, a second power group, and an aperture stop. In an embodiment, the optical component is disposed between the first power group and the aperture stop. In an exemplary embodiment, the optical component is proximate to the aperture stop. By disposing the optical component closer to or proximate to the aperture stop in the lens arrangement, various benefits may be realized, including improved contrast uniformity.

Abstract: A stereo projection apparatus includes a polarized beam splitter assembly for splitting a projecting light beam into a transmitted light beam, a first reflective light beam and a second reflective light beam; a polarization state transforming assembly for adjusting the polarization state of the transmitted light beam or the polarization state of the first reflective light beam and second reflective beam; a light path direction adjustment assembly for adjusting a travel direction of the transmitted light beam or a travel direction of the first reflective light beam and the second reflective light beam; a light beam size adjustment assembly for adjusting a coverage range of the transmitted light beam or a coverage range of the first reflective light beam and the second reflective light beam; and a light modulator for modulating the adjusted transmitted light beam, first reflective light beam and second reflective light beam to left-circularly polarized light and right-circularly polarized light in accordance wi

Abstract: A liquid crystal display device (1) includes a liquid crystal panel having a plurality of pixels disposed in a matrix form, and a patterned retarder having retarder plates (RR) and retarder plates (RL) formed at positions corresponding to odd-numbered rows and even-numbered rows, respectively, of the liquid crystal panel. Among sub pixels disposed in the pixels positioned in the n-th row, a sub pixel electrode of a boundary-proximity sub pixel, which is positioned closest to a boundary between the associated retarder plate (RR) and the associated retarder plate (RL), is connected to an auxiliary bus line via a transistor having a gate electrode connected to a gate bus line in the (n?1)-th or prior row. In the second display mode, gate signals are sequentially supplied to the gate bus lines in order from the first to the N-th rows, and, in the first display mode, gate signals are sequentially supplied to the gate bus lines in order from the N-th to the first rows.

Abstract: A stereoscopic image apparatus that is capable of minimizing loss of optical energy and improving quality of a stereoscopic image is disclosed. The stereoscopic image apparatus includes a polarizing beam splitter to reflect or transmit incident light based on polarization components of the light to split the light in at least three different directions, a reflective member to reflect the light reflected by the polarizing beam splitter to a screen, at least one modulator to modulate the light reflected by the reflective member and the light transmitted through the polarizing beam splitter, and a refractive member disposed in an advancing direction of light to be incident upon the polarizing beam splitter to refract the light to be incident upon the polarizing beam splitter.

Abstract: A polarization controller adapted to output respective projection lights for a right-eye image and a left-eye image that are incident from a projector to a screen in different polarization directions, includes: a liquid crystal device adapted to change the polarization directions of the projection lights; and a controller adapted to control the liquid crystal device so that the respective projection lights for the right-eye image and the left-eye image have different polarization directions, wherein the controller performs control for mirror-reversing the polarization directions of the projection lights in the liquid crystal device according to a control signal indicating whether the projector performs mirror reversal of the right-eye image and the left-eye image, input from the projector.

Abstract: In embodiments of a multiple waveguide imaging structure, an imaging structure includes a first waveguide for see-through viewing of an environment at a first field of view, and includes a second waveguide for see-through viewing of the environment at a second field of view. The first and second waveguides each include a polarizing beam splitter to reflect light that enters at a first polarization orientation angle in the respective first and second waveguides, and the polarizing beam splitters pass through the light that enters at a second polarization orientation angle. The imaging structure also includes a polarization switch to rotate the polarization of the light through the first and second polarization orientation angles.

Abstract: Various embodiments relate to a method for projecting a 3D image onto a projection surface, which includes a first and a second partial images for a right and left eyes of a first viewer, respectively. A first illumination beam, which has electromagnetic radiation of a predetermined first property, is produced depending on first image data. A second illumination beam, which has electromagnetic radiation of a predetermined second property different from the first property, is produced depending on second image data. The first and the second illumination beam are deflected towards the projection surface such that the first and the second illumination beams produce a first and a second beam spots thereon, respectively. The first and the second beam spots are moved across the projection surface such that the first and the second partial images are shown with the aid of the first and the second beam spot, respectively.

Abstract: A projector includes a lamp that emits projection light to project 3D picture, in which a right eye image and a left eye image are represented in a time division manner, to an object, a synchronization signal transmission section which transmits shutter synchronization signal to glasses having a right eye shutter and a left eye shutter to control the opened state or the closed state of the right eye shutter and the left eye shutter, based on the signal indicating a displaying period of the right eye image and the left eye image of 3D picture, and a lamp drive section that supplies AC current having peak overlapping with a period when the right eye shutter of the glasses is in the opened state and peak overlapping with a period when the left eye shutter of the glasses is in the opened state to the lamp, based on the signal.

Abstract: A method is provided for projecting a three-dimensional image. The method includes providing a first light source that emits first eye images and a second light source that emits second eye images. A polarization of the first light source is orthogonal to a polarization of the second light source. A first eye image of a first color is projected from the first light source. A second eye image of the same first color is projected from the second light source. A first eye image of a second color is projected from the first light source. A second eye image of the same second color is projected from the second light source. A first eye image of a third color is projected from the first light source. A second eye image of a third color is projected from the second light source.

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 external polarization conversion device used for a projector includes a first element which converts light from the projector to polarized light in a uniform polarization direction, and a second element which is arranged in a position subsequent to the first element in such a way that there is a space between the first element and the second element and which converts the polarized light from the first element to predetermined polarized light that is different from the polarized light from the first element.

Abstract: A method is provided for projecting a three-dimensional image. The system includes a first light source, the first light source emitting light in a first direction and a second light source emitting light in a second direction. A beam splitter device is disposed adjacent each light source and an imaging device is disposed adjacent the beam splitter device. Light from the first light source and the second light source travel a common optical path to a projector lens assembly.

Abstract: A polarization conversion system (PCS) is located in the output light path of a projector. The PCS may include a polarizing beam splitter, a polarization rotating element, a reflecting element, and a polarization switch. Typically, a projector outputs randomly-polarized light. This light is input to the PCS, in which the PCS separates p-polarized light and s-polarized light at the polarizing beam splitter. P-polarized light is directed toward the polarization switch on a first path. The s-polarized light is passed on a second path through the polarization rotating element (e.g., a half-wave plate), thereby transforming it to p-polarized light. A reflecting element directs the transformed polarized light (now p-polarized) along the second path toward the polarization switch. The first and second light paths are ultimately directed toward a projection screen to collectively form a brighter screen image in cinematic applications utilizing polarized light for three-dimensional viewing.

Abstract: A projection device may include at least one first laser device and one second laser device, which is arranged opposite the first laser device. A prism is arranged between the two laser devices, wherein a polarization-dependent mirror device is arranged in the prism in such a manner that the beam of the first laser device is reflected in a direction that extends opposite the direction in which the beam of the second laser device is reflected. The polarization of the beam of the second laser device is then rotated, and the beam is deflected back to the polarization-dependent mirror device. The beam of the second laser device now passes through the mirror device without reflection due to the change in the polarization of the beam of the second laser device, such that two superposed laser beams of different polarization are available at the output of the projection device.