Abstract: Disclosed is a manufacturing method for a stepped imaging directional backlight apparatus which may include a structured optical film and a tapered body. The structured optical film may include multiple optical functions and may be assembled by folding onto the tapered body, reducing cost and complexity of manufacture.

Abstract: Generally, this disclosure concerns the angle sensitivity of polarization switch elements and the resulting impact of the ray direction on performance. More specifically, apparatus and techniques for compensating the angular sensitivity of liquid crystal (LC) polarization switches are described that enhance the performance of polarization switches. For example, a polarization switch is disclosed that transforms linearly polarized light of an initial polarization orientation that includes a first and second liquid crystal cell with a compensator located between the LC cells. The compensator layer is operable to enhance the field of view through the polarization switch. Such compensation techniques are particularly useful for short-throw projection environments.

Abstract: A direct view display provides a light modulating panel and a backlight including first and second sets of spectral emitters. The first set of spectral emitters generate a first light bundle and the second set of spectral emitters generate a second light bundle. Several modes of operation may be provided including (1) an advanced 2D mode, (2) an enhanced color gamut mode employing simultaneous illumination of the first and second set of spectral emitters, (3) a privacy screen mode, (4) a channel multiplexed mode, and (5) a stereoscopic image mode. The latter three modes utilize the first and second set of spectral emitters to alternately illuminate a portion of the light modulating panel. Images and representations generated by the direct view display operating in the latter three modes are viewed using appropriate eyewear having filters with passband characteristics to transmit the respective light bundle.

Abstract: Disclosed is a light guiding valve apparatus including a light valve, a two dimensional light emitting element array and an input side arranged to reduce light reflection for providing large area directional illumination from localized light emitting elements with low cross talk. A waveguide includes a stepped structure, in which the steps may include extraction features hidden to guided light propagating in a first forward direction. Returning light propagating in a second backward direction may be refracted or reflected by the features to provide discrete illumination beams exiting from the top surface of the waveguide. Stray light falling onto a light input side of the waveguide is at least partially absorbed.

Abstract: Disclosed is an imaging directional backlight polarization recovery apparatus including an imaging directional backlight with at least a polarization sensitive reflection component with optional polarization transformation and redirection elements. Viewing windows may be formed through imaging individual light sources and hence defines the relative positions of system elements and ray paths. The base imaging directional backlight systems provide substantially unpolarized light primarily for the illumination of liquid crystal displays (LCDs) resulting in at least 50% loss in light output when using a conventional sheet polarizer as input to the display. The invention herein introduces a polarization sensitive reflecting element to separate desired and undesired polarization states for the purposes of transformation and redirection of the reflected light for usable illumination.

Abstract: Polarization preserving projection screens provide optimum polarization preservation for 3D viewing. The projection screens additionally provide improved light control for enhanced brightness, uniformity, and contrast for both 2D and 3D systems. Generally, the disclosed method for providing a projection screen comprises stripping an optically functional material from a carrier substrate, thus creating engineered particles from the optically functional material. The engineered particles may then be deposited on a second substrate to create a substantially homogeneous optical appearance of the projection screen.

Abstract: Three dimensional projection systems may be single projector or multiple projector systems. These 3D projection systems may include a one or more polarization conversion systems (PCS). Each PCS may be designed for relatively small throw ratios and thus, may be designed to accommodate the small throw ratios. Each PCS may include a polarizing beam splitter, a first optical stack, a reflector and a second quarter wave retarder. The first optical stack may include a rotator, a polarizer, a polarization switch and a first quarter wave retarder. Each PCS may receive light from a respective projector, and the PBS in each PCS may direct the light toward the first optical stacks. The light may be converted to a different polarization state as it passes through the first optical stack. The converted light may then be re-directed by a reflecting element to a second quarter wave retarder. The second quarter wave retarder may convert linearly polarized light to circularly polarized light.

Abstract: Proposed are various embodiments of projection systems that generally provide stereoscopic images. The projection systems act to split a spatially separated image in a stereoscopic image frame and superimpose the left- and right-eye images on a projection screen with orthogonal polarization states. The embodiments are generally well suited to liquid crystal polarization based projection systems and may use advanced polarization control.

Abstract: A front projection screen is provided having a first portion of material and a second portion of material. The first and second portions of material may have an undercut edge profile, and the first and second portions of material may be perforated, such that the perforations allow the first and second portions of material to be at least somewhat acoustically transmissive while substantially maintaining optical efficiency from the front side of the front projection screen. Such optical efficiency has particular utility in stereoscopic projection applications utilizing polarized encoded light.

Abstract: Methods to substantially reduce or eliminate optical non-uniformity across an interface may also substantially improve the strength and ease of seam manufacturing, including joining substrates. The methods may include managing optical non-uniformities at least by broadening a region over which a change in optical loss may occur and/or by maintaining a substantially constant average optical loss across an interface. The methods may also include forming a seam that substantially reduces the appearance of optical non-uniformities at the seam, which may include maintaining approximately constant average loss in the vicinity of the seam by substantially controlling reflectivity in the vicinity of the seam, in which substantially controlling reflectivity in the vicinity of the seam may include employing a backer treated to minimize optical reflectivity over a range of angles.

Abstract: Polarization preserving projection screens provide optimum polarization preservation for 3D viewing. The projection screens additionally provide improved light control for enhanced brightness, uniformity, and contrast for both 2D and 3D systems. Generally, the disclosed method for providing a projection screen comprises stripping an optically functional material from a carrier substrate, thus creating engineered particles from the optically functional material. The engineered particles may then be deposited on a second substrate to create a substantially homogeneous optical appearance of the projection screen.

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: Polarization modulation with in-plane switching of liquid crystals (LCs) may be used in active retarder stereoscopic display systems where viewers wear passive eyewear to see isolated left and right eye images. Embodiments of the present disclosure may include nematic LC or fast switching ferroelectric liquid crystal (FLC), depending on the desired performance.

Abstract: Proposed are various embodiments of projection systems that generally provide stereoscopic images. The projection systems act to split a spatially separated image in a stereoscopic image frame and superimpose the left- and right-eye images on a projection screen with orthogonal polarization states. The embodiments are generally well suited to liquid crystal polarization based projection systems and may use advanced polarization control.

Abstract: A method for driving at least one shutter glass lens having a property of light retardation that is variable at least according to the wavelength of the light passing through it, the shutter glass lens having an LC cell driven to a relatively “on” or a relatively “off” state according to a voltage applied across it. The lens is further operable to pass temporally modulated color display images of at least first, second, and third wavelengths being applied to a display surface, further including first, second, and third holding voltages to the LC cell in decreasing magnitude to stabilize the retardation of the lens for first, second, and third display image wavelengths.

Abstract: A polarization switch provides substantially ideal binary polarization switching over a broad range of wavelengths using a polarization modulation wheel having at least one retarder stack that transforms polarization. Using the polarization modulation wheel in a polarization system provides a high throughput polarization switch and operates over a wide range of incidence angles while providing substantially continuous and smooth polarization output for each component for any selected polarization basis set. The polarization modulation wheel is well-suited for stereoscopic polarized projection applications.

Abstract: Projection systems and methods for providing stereoscopic images viewed through passive polarizing eyewear. The systems relate to projectors that create left and right eye images simultaneously and often as side-by-side images on the image modulator. The systems act to superimpose the spatially separated images on a projection screen with alternate polarization states. The embodiments are best suited to liquid crystal polarization based projection systems and use advanced polarization control.

Abstract: Disclosed embodiments relate to eyewear configured to reduce stray light. An exemplary embodiment of the eyewear accounts for various design factors, including the cross sectional profile of the rim, the micro topography of the rim surface, the reflectivity, the theatre or room geometry, proximity of the eye to the lens, lens size, and the screen gain. An exemplary eyewear includes lenses connected to the rim sections of a frame, and a path may be defined through a maximum height of the outer flange portion of a rim section and a maximum height of the inner flange portion of the rim section. The path may be inclined at an angle relative to an angle ? relative to a longitudinal axis defined by the lenses.

Abstract: Disclosed herein are systems and related methods for reducing speckle on display screen. More specifically, screen vibration is used to reduce speckle, and in accordance with the disclosed principles, the vibration may be achieved by using wave-based actuation (e.g., acoustic or electromagnetic waves) to vibrate the screen. In an exemplary embodiment, a speckle reducing system may comprise at least one actuating element located proximate to, but not in physical contact with, a display screen. In addition, the at least one actuating element may be configured to generate waves directed towards the display screen. When the waves impact the display screen, the waves impart vibration to the display screen.

Abstract: Three dimensional projection systems may be single projector or multiple projector systems. These 3D projection systems may include a polarization conversion system (PCS). The PCS may be designed for relatively small throw ratios and thus, may be designed to accommodate the small throw ratios. The PCS may include a polarizing beam splitter, a first optical stack, a reflector and a second quarter wave retarder. The first optical stack may include a rotator, a polarizer, a polarization switch and a first quarter wave retarder. The PCS may receive light from a projector and the PBS may direct the light toward the first optical stack. The light may be converted to a different polarization state as it passes through the first optical stack. The converted light may then be re-directed by a reflecting element to the second quarter wave retarder. The second quarter wave retarder may convert linearly polarized light to circularly polarized light.