Abstract: Curved polarization filters and methods of manufacturing such filters. The method includes laminating a planar polarization layer to a planar retarder layer at a predetermined orientation and bending the laminate to create a curved filter. The strain on the retarder layer results in stress-induced birefringence, and the predetermined orientation of the retarder substantially compensates for the stress-induced birefringence. In some embodiments, the predetermination is based on mathematical models. In some other embodiment, the predetermination is based on experimental data.

Abstract: A stiffening strip at selected edges of a screen may enable the use and mounting of a high-elastic modulus substrate screen material. Such screen materials may be engineered to provide polarization-preserving characteristics, and be applied to or part of the high-elastic modulus substrate. Furthermore, the stiffening strip may enable the use of screen vibration techniques to reduce speckle in display applications that use projection screens, particularly those display applications using illumination sources prone to speckle such as laser-based projection. The screen vibration may be provided by a vibrating device attached to the stiffening strip.

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 embossing at least a first side of a first substrate to produce an optically functional material and then cutting the optically functional material into pieces to produce a plurality of engineered particles. The plurality of engineered particles may then be deposited on a second substrate to produce a substantially homogeneous optical appearance of the projection screen.

Abstract: By introducing a stack of alternating high and low index dichroic material layers on the exit surface of a waveguide for a wedge type directional backlight, natural reflectivity differences between polarized components can be increased, effectively reflecting the vast proportion of S-polarized light rays, while at the same time transmitting the P-polarized light rays, of light impacting the exit surface of the waveguide at an angle sufficient to exit the waveguide. This recovers polarization in wedge type backlight systems, increasing illumination exiting the waveguide. Also, on the back reflecting surface of the waveguide, a birefringent material can be added to efficiently transform S-polarized reflected light from the dichroic stack, into returning P-polarized light.

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: Disclosed is a light guiding valve apparatus comprising an optical valve, a two dimensional light source array and a focusing optic for providing large area collimated illumination from localized light sources. A stepped waveguide may be a stepped structure, in which the steps may be extraction features optically hidden to guided light, propagating in a first forward direction. Returning light propagating in a second backward direction may be refracted, diffracted, or reflected by the features to provide discrete illumination beams exiting from the top surface of the waveguide. A two dimensional array of viewing windows may be produced. Such controlled illumination may provide for efficient, multi-user autostereoscopic displays with wide viewing freedom and low cross talk and near-eye displays that are substantially transparent.

Abstract: Two or more spectral emitters are used to provide spectrally separated light illumination onto modulating pixels of a visual display. The spectral emitters may be lasers or LEDs, typically having coherent properties. Generally, a display system includes a spectral emitter array, a light collimating element, a lens array, and a light modulating panel. The spectral emitter array includes a first spectral emitter operable to emit light of a first wavelength and a second spectral emitter operable to emit light of a second wavelength. The light collimating element is operable to direct light from the spectral emitter toward the lens array, and the lens array is operable to direct light toward the light modulating panel.

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: Disclosed is an imaging directional backlight including an array of light sources, and a control system arranged to provide variable distribution of luminous fluxes, scaled inversely by the width associated with the respective light sources in the lateral direction, across the array of light sources. The luminous intensity distribution of output optical windows may be controlled to provide desirable luminance distributions in the window plane of an autostereoscopic display, a directional display operating in wide angle 2D mode, privacy mode and low power consumption mode. Image quality may be improved and power consumption reduced.

Abstract: A method and apparatus for reduction of ghost images in stereoscopic images. This disclosure provides a ghost compensation apparatus and methods that detect affected regions where ghosting may occur in a stereoscopic image, yet where conventional ghost compensation techniques are ineffective because there is insufficient luminance overhead to conduct a conventional ghost compensation process. Luminance values are modified in such regions prior to applying a ghost compensation process.

Abstract: Disclosed is an imaging directional backlight apparatus for providing large area uniform directed illumination from localized light sources. Within an exemplary optical valve system, a waveguide comprises a stepped structure, where the steps comprise extraction features hidden to guided light, propagating in a first forward direction. Returning light propagating in a second backward direction may be refracted, diffracted, or reflected by the features to provide discrete illumination beams exiting from the top surface of the waveguide. Such controlled illumination may provide for efficient, multi-user autostereoscopic displays as well as improved 2D display functionality. Illumination uniformity is provided by the positioning, packaging, and optically modifying of individual input sources. The latter employs non-imaging and refractive optics.

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 an imaging directional backlight that cooperates with a spatial light modulator to direct light into a first viewing window for one set of image pixels and into a second viewing window for a second set of image pixels. The waveguide may comprise a stepped structure, where the steps further comprise extraction features hidden to guided light, propagating in a first forward direction. Returning light propagating in a second backward direction may be refracted, diffracted, or reflected by the features to provide discrete illumination beams exiting from the top surface of the waveguide. Viewing windows are formed through imaging individual light sources and hence defines the relative positions of system elements and ray paths. Such an apparatus may be used to achieve an autostereoscopic display with a flat structure, not requiring fast response speed spatial light modulators.

Abstract: Disclosed is a light guiding valve apparatus including an imaging directional backlight, an illuminator array and an observer tracking system arranged to achieve control of an array of illuminators which may provide a directional display to an observer over a wide lateral and longitudinal viewing range, wherein the number of optical windows presented to the observer as viewing windows is controlled dependent on the lateral and longitudinal position or speed of an observer.

Abstract: Disclosed is an autostereoscopic display apparatus comprising a light guiding valve apparatus including an imaging directional backlight, an illuminator array and an observer tracking system arranged to achieve control of an array of illuminators which may provide a directional display to an observer over a wide lateral and longitudinal viewing range with low flicker.

Abstract: Disclosed is an optical inline light guiding apparatus which may include a substantially parallel planar light expansion section and a light extraction section comprising a stepped structure, in which the steps may be extraction features and guiding features. Such controlled illumination may provide for efficient, multi-user autostereoscopic displays with wide viewing freedom, high efficiency and low cross talk and other directional display uses.

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: A method for providing optimal correction to depth mapping between captured and displayed stereoscopic content. The solution is derived in a continuous form that can be implemented through CGI scaling techniques compatible with image rendering techniques. Similar correction can be implemented with variable depth-dependent camera separation and disparity re-mapping. The latter is applicable to correcting existing stereoscopic content.

Abstract: Disclosed herein are architectures for an external cavity laser. In some embodiments, the external cavity laser includes vertical cavity surface emitting laser (VCSEL) elements, a Brewster plate, frequency doubling chips, and a microlens array. The Brewster plate is arranged at an angle relative to the light path, and is configured to polarize at least the light received from the VCSELs and propagating on the light path in a first direction, and extract, from the external cavity, frequency-doubled light propagating on the light path in a second direction opposite to the first direction. The doubling chips are operable to receive the light and double the frequency of a portion of the received light. The microlens array is aligned with the VCSEL elements. A mount may be employed to mount the side stack of doubling chips by either side mounting or end mounting.

Abstract: The present disclosure is directed to autostereoscopic display systems operable to provide increased number of views and related methods. One embodiment of the display systems comprises a light-modulating display panel comprising a first set of colored subpixels and a second set of colored subpixels, and the number of subpixels in the first set of colored subpixels is greater than the number of subpixels in the second set of colored subpixels. The display system further comprises a lenticular sheet disposed in light paths of the colored subpixels of the display panel.