Abstract: The present invention relates to a time-multiplexed stereoscopic 3d projection system that provides a higher level of on-screen image-brightness and image quality as compared to other prior-art technologies based on a single-beam architecture. The invention is based on the insight that a polarization beam-splitting element can be arranged to split an incident image-beam generated by a projector into one transmitted image-beam and at least one reflected image-beam, wherein each of said transmitted and reflected image-beams possess the same common state of polarization. Furthermore, by utilization of at least one reflecting surface, polarization rotator, polarization modulator, polarization-preserving projection-screen and passive polarized viewing-glasses, a stereoscopic 3d projection system is disclosed that provides for a high level of on-screen image-brightness and image quality.

Abstract: The present invention relates to a time-multiplexed stereoscopic 3d projection system wherein the image-beam from a digital cinema projector is separated by a polarization beam-splitting element into one primary image-beam possessing a first state of polarization and at least one secondary image-beam possessing a second state of polarization. Polarization modulators are provided in order to modulate the polarization state for each of said primary and secondary image-beams thereof and arranged so that all left-eye images possess a first modulated state of polarization and all right-eye images possess a second modulated state of polarization.

Abstract: The present invention relates to a time-multiplexed stereoscopic 3d projection system wherein the image-beam from a digital cinema projector is separated by a polarization beam-splitting element into one primary image-beam possessing a first state of polarization and at least one secondary image-beam possessing a second state of polarization. Polarization modulators are provided in order to modulate the polarization state for each of said primary and secondary image-beams thereof and arranged so that all left-eye images possess a first modulated state of polarization and all right-eye images possess a second modulated state of polarization.

Abstract: The present invention discloses the design of active 3d shutter-glasses for the viewing of time-multiplexed stereoscopic three dimensional (3d) images that offer both an improved level of on-screen image-brightness as well as reduced manufacturing costs as compared to other prior-art technologies. The disclosed invention is based on the insight that a tangential in-plane electrical-field can be utilized in order to provide for a voltage-assisted relaxation switching step together with cholesteric liquid crystal materials, thereby increasing the relaxation speed of said cholesteric liquid crystal materials thereof. Furthermore, dichroic-dye materials can additionally be added to said cholesteric liquid crystal materials in order to absorb at least some of the scattered light and hence reduce the overall level of perceived on-screen image-haze.

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: An optical polarization device for a stereoscopic image projector, including: a polarizer optical element including two beam splitter-polarizer plates, joined to one another; first and second optical reflectors configured to modify, respectively, a trajectory of first and second light beams reflected such that the reflected and transmitted light beams are projected to form one and same stereoscopic image; first, second, and third polarization modulators configured to selectively switch the optical polarization, respectively, of a transmitted light beam, of the first and of the second reflected light beams, between the first and second states of optical polarization; and a control circuit for the polarization modulators.

Abstract: A time-multiplexed stereoscopic 3d projection system including a beam-splitting element to split the randomly polarized image-beam generated by a single-lens projector into one primary image-beam, possessing a first state of linear polarization, and two secondary image-beams, both possessing a second state of linear polarization. The polarization states are mutually orthogonal. The primary and secondary image-beams recombine to form a complete image on the surface of a polarization-preserving projection-screen. There are polarization modulators that modulate the first and second states of linear polarization between a left and right circular polarization state. There is a contrast enhancement film in the optical-path of the primary or secondary image-beams located between the polarization modulator and the projection-screen.

Abstract: A 3-d projection system including first and second projectors generates left and right eye image beams. There is a first beam-splitting element to split the left-eye image beam into a primary left-eye image beam and two secondary left-eye image-beams and a second beam-splitting element to split the right-eye image beam into a primary right-eye image beam and two secondary right-eye image beams. The primary and secondary image beams have first and second linear polarization states, respectively. There is a first optical quarter waveplate device configured to receive the primary left-eye image beam and two secondary left-eye image beams and to convert their linear polarization states to a first circular polarization orientation. There is a second optical quarter waveplate device configured to convert the primary right-eye image beam and two secondary right-eye image beams to a second circular polarization orientation. The first and second circular polarization orientations are mutually orthogonal.

Abstract: An optical polarization device for a stereoscopic image projector, including: a polarizer optical element including two beam splitter-polarizer plates, joined to one another; first and second optical reflectors configured to modify, respectively, a trajectory of first and second light beams reflected such that the reflected and transmitted light beams are projected to form one and same stereoscopic image; first, second, and third polarization modulators configured to selectively switch the optical polarization, respectively, of a transmitted light beam, of the first and of the second reflected light beams, between the first and second states of optical polarization; and a control circuit for the polarization modulators.

Abstract: A device for polarization of a video sequence to be stereoscopically viewed has a beam splitter, cells, mirrors, and a control circuit. The beam splitter receives an incident beam and separates it into two beams with perpendicular polarizations. It has four prisms, each with perpendicular faces. The first face of each prism has a phase-delaying plate, and the second face of each prism has a layer that reflects the first polarization and transmits the second. The prisms are arranged such that a first face of each prism is next to a second of an adjacent prism. The cells have variable polarization rotation and are crossed by the beams. Each mirror reflects a beam. The control circuit defines a polarization rotation of the cells such that the beams, after having crossed corresponding cells, have a common polarization that alternates between two perpendicular states.

Abstract: The invention relates to liquid crystal lenses having dynamically switchable light transmission, including: a shutter (2) including two transparent substrates (21, 22) and a nematic liquid crystal layer (20) arranged between the substrates (21, 22); and a control circuit capable of alternately applying a bias voltage or a relaxation voltage across the liquid crystal to render the shutter (2)clear or opaque, the falling edges between the bias voltage and the relaxation voltage having a duration of 80 to 900 ?s.

Abstract: The invention relates to liquid crystal lenses having dynamically switchable light transmission, including: a shutter (2) including two transparent substrates (21, 22) and a nematic liquid crystal layer (20) arranged between the substrates (21, 22); and a control circuit capable of alternately applying a bias voltage or a relaxation voltage across the liquid crystal to render the shutter (2) clear or opaque, the falling edges between the bias voltage and the relaxation voltage having a duration of 80 to 900 ?s.