Abstract: The present invention provides a high brightness color selective light modulator (CSLM) formed by a polarization modulator positioned between two retarder stacks. The modulator changes the apparent orientation of one retarder stack relative to the other so that, in a first switching state of the modulator the two retarder stacks cooperate in filtering the spectrum of input light, and in a second switching state the two retarder stacks complement each other, yielding a neutral transmission spectrum. Two or more CSLM stages can be used in series, each stage providing independent control of a primary color. One preferred embodiment eliminates internal polarizers between CSLM stages, thereby providing an additive common-path full-color display with only two neutral polarizers. Hybrid filters can be made using the CSLMs of this invention, in combination with other active or passive filters.

Abstract: The disclosed technique employs a process for mating polarizing wafers to clear lenses using a high-yield bonding process. A thermoformed polarizing wafer is bonded to a clear lens of similar curvature via a solvent bonding process. In one embodiment, a system includes a translation stage configured to press a first lens to a second, with a solvent therebetween, such that a portion of the first lens initially contacts a portion of the second lens. An alignment fixture holding the second lens conforms to the curvature of the second lens, and a deformable sheet mounted proximate to the alignment fixture flexes in response to the force so that either of the first or second lenses conforms to a curvature of the other, and so that the pressure of the first lens against the second lens presses the solvent radially outward to the perimeter of the second lens to bond the first lens to the second lens.

Abstract: Described is an optical compensator device that can maintain a high degree of performance in the demanding environment of projection display. A mounting process involves using a sealant between optically clear glass or ceramic substrate and low elastic polymer retarder film. The sealant may mitigate or prevent the degradation of the retarder film by acting as an oxygen barrier that seals the substrate and increases the lifetime of the device in high luminance.

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: Chemically-bonded retarder stacks are provided in this disclosure. A first organic layer having a first molecular orientation is chemically welded to a second organic layer having a second molecular orientation. The first and second molecular orientations are crossed when the organic layers are laminated. The first and second organic layers may be polycarbonate films, which can be welded together using a suitable solvent.

Abstract: Described are various compensators for compensating for in-plate and out-of-plane retardances of LC panels in their dark states.

Abstract: Disclosed is 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, the method comprising 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: Described in the present application are multiple systems for high-performance compensated shutter lens designs, including compensators for compensating for performance problems that stem from real-world performance limitations in present shutter-glass designs.

Abstract: Described are various compensators for compensating for in-plate and out-of-plane retardances of LC panels in their dark states.

Abstract: A sequential color system with reduced or eliminated global temporal notching losses may be implemented with a buffered display panel. Fast global blanking and/or inter-field images may be used to reduce or eliminate the global temporal notching losses. When consecutive states of a pixel are “on,” an inter-field image may be displayed by maintaining the pixel in an “on” state instead of turning the pixel “off” and then turning the pixel “on.” This improves the color brightness and saturation. The display may be implemented with a color wheel or with a color switch.

Abstract: The present application describes a retarder stack color switch using a single polarization analyzer for reflective-mode projection displays. The single polarization analyzer permits additive mode switching, which optimizes the chrominance of the additive primary outputs and the black state. Moreover, the single analyzer color switch provides a white state, which is frequently used in sequential systems. The single analyzer color switch overcomes some of the cost and manufacturing challenges associated with conventional transmissive full color switches based on retarder-stack-filters. The single analyzer color switch according to an embodiment uses a split-path so that relatively weak colors can follow a “high-efficiency” path.

Abstract: A birefringent network can be formed from a pair of beam directing elements that sandwich a birefringent filter. One of the beam director elements can be a polarizing beam splitter and the other of the beam director elements can be a reflector or polarizing beam splitter. The polarizing beam splitters can be formed by an anisotropic material sandwiched between two isotropic pieces and can include optical films to couple both polarizations of light into and out of the beam splitters. The polarizing beam splitters also can be formed by anisotropic material on either side of an isotropic bow-tie piece, all of which is sandwiched a pair of isotropic pieces. A birefringent network also can be formed by a pair of bulk birefringent beam splitters sandwiching a birefringent filter. Little or no polarization mode dispersion occurs in these birefringent networks since all of the beams travel the same distances through the same elements.

Abstract: Projection systems having o-plate compensation elements are described. The compensation elements may be negative, positive or biaxial anisotropic element and may have a homogeneous tilt or a splayed tilt. The compensation elements may be formed from a polymer liquid crystal. The compensation elements are designed to maximize azimuth-averaged contrast. The compensation elements may be placed on the same side of a liquid crystal panel when a micro-lens array is used to improve the ease of manufacture.

Abstract: The selective filtering of light by polarization interference may be used to enhance vision and/or protect eyes from harmful light rays. For example, such filtering may be used in sunglasses, color corrective eyewear or protective eyewear. The selective filtering of incident light may provide any desired spectral transmission (including visible light and light not visible to the eye) and is performed by a pair of polarizing elements that sandwich a retarder stack. The filtering structure may be formed by multi-layer polarizing structures and may be formed by fabricating sheet laminates that are die cut to form inexpensive laminates. The laminates may be flat or curved in one (e.g., wrap-around) or more dimensions.

Abstract: A light source for sequential or scrolling displays that recycles otherwise unusable light. The recycling is achieved by reflecting that portion of the light spectrum that will not be used by a pixel back into the light pipe where the light is rehomogenized or redistributed. The rehomogenized or redistributed light may then be used by other pixels that can uses that portion of the light spectrum. The reflection or transmission of the light through a reflective polarizer is controlled by a polarization rotation element that rotates certain portions of the spectrum according to excitation.

Abstract: The present application describes color management architecture for a three-panel projection system that utilizes color selective polarization filters (CSPF) and polarizing beam splitting elements. An exemplary embodiment describes a color management architecture with a dichroic input beam splitter and three polarizing beam splitters. An output polarizing beam splitter is used as an analyzer. The color management system architecture can isolate any color channel from those remaining whose separation and combination are then carried out by a single beamsplitting element. The disclosed embodiments also provide an improvement in the ANSI contrast. In some embodiments, an achromatic quarter-wave plate is used in combination with a color filter to block the light reflected from projection optics.

Abstract: Disclosed are color management architectures used in video projection systems including, for example, retarder stacks sensitive to the symmetries between input and output polarizer configurations that provide the polarization transformations that will comprise for skew rays, such that normal incidence performance is maintained for all incident light. Additionally, also disclosed are systems that utilize color selective polarization (CSP) filters and polarizing beam splitting elements such that an output analyzer is not required. One exemplary CSP architecture includes two CSPs, a single polarizing beam splitting element combination for splitting and combining light between two of the three panels, and an output polarizing beam splitting element used as an analyzer such that a single CSP is in the projection path.

Abstract: Beamsplitters are frequently used in projectors based on reflective liquid crystal display for separating input and output light, and more recently for color management systems. Rather stack filters are used in such systems to orthogonally polarize primary colors, converting polarizing beamsplitters to color splitters and combiners. Geometric polarization rotations induced by beamsplitters at moderate f-numbers have the effect of significantly degrading performance. Because retarder stacks in general rely on a specific input polarization to perform properly, such skew rays are responsible for color cross-talk. Retarder stacks designed according to the present invention are sensitive to the symmetries that exist between input and output polarizer configurations. These stacks provide the polarization transformations that will compensate for skew rays, such that normal incidence performance is maintained for all incident light.

Abstract: A system for separating light into different spectrums and for recombining the light includes at least one polarizing beamsplitter and at least one retarder stack configured to condition the polarization of input light differently for different spectrums. A device embodying the invention could utilize multiple polarizing beamsplitters and multiple retarder stacks. Alternatively, a system could utilize a single polarizing beamsplitter and a single retarder stack in combination with one or more dichroic beamsplitters. In preferred embodiments, one or more reflective modulator panels are included to separately modulate each separated spectrum of light. Such an embodiment can be used for a color projection system. In each of the embodiments that utilize modulators, distances between the modulators and the focusing optics is essentially the same.

Abstract: The present invention provides a high brightness color selective light modulator (CSLM) formed by a polarization modulator positioned between two retarder stacks. The modulator changes the apparent orientation of one retarder stack relative to the other so that, in a first switching state of the modulator the two retarder stacks cooperate in filtering the spectrum of input light, and in a second switching state the two retarder stacks complement each other, yielding a neutral transmission spectrum. Two or more CSLM stages can be used in series, each stage providing independent control of a primary color. One preferred embodiment eliminates internal polarizers between CSLM stages, thereby providing an additive common-path full-color display with only two neutral polarizers. Hybrid filters can be made using the CSLMs of this invention, in combination with other active or passive filters.