Abstract: The present invention provides overhead having (a) a main body having a stage area, (b) a head assembly, and (c) a post suspending the inverted head assembly over the stage area. The post is pivotally attached to the main body in accordance with equation Clearance={square root over ((Mx−Px)2+(My−Py)2)}−{square root over ((Fx−Px)2+(Fy−Py)2)} and the post is outside the stage area. In a preferred embodiment, the head assembly is an inverted head assembly.

Abstract: An overhead projector including a Fresnel lens, a single element meniscus projection lens having a concave side and a convex side, and a folding mirror placed in an optical path between the Fresnel lens and the projection lens. The projection lens is oriented to have the concave side optically facing the Fresnel lens. The optical design of the overhead projector follows the following equation, FFres=(FLens(MLens+1)/MLens−SLD)/(MFres+1), where the Fresnel lens has a focal length FFres, and a magnification MFres, the projection lens has a focal length FLens and a magnification MLens, and SLD is the distance from the stop position and the projection lens.

Abstract: A front image projection device and corresponding method are disclosed that utilize a shaped imager component to pre-distort an input image and thereby compensate for the distortion expected in a screen image. The front projection device includes projection components, image generating components, and illumination components. The shaped image component may compensate at least in part for distortion introduced due to the components of the projection system. The physical configuration for the shaped imager may be determined through a modeled or actual ray trace through the projection system, and the resulting physical configuration may be a geometric shape having a curved top, a curved bottom and curved sides.

Abstract: A three dimensional optical circuit featuring an optical manifold for organizing, guiding and protecting individual optical fibers is shown. One aspect of the present invention is a three dimensional manifold which may be constructed using a rapid prototyping process such as, but not limited to, stereolithography (“SLA”), fused deposition modeling (“FDM”), selective laser sintering (“SLS”), and the like. The manifold has a number of input openings in a first ordered arrangement at one end connected by passageways to a number of output openings in a second ordered arrangement at the opposite end. A plurality of optical fibers may be directed through the passageways of the manifold to produce a three dimensional optical circuit such as a shuffle. Moreover, the optical manifold may be used in conjunction with a number of connections or terminations to form a various optical modules. These modules may be configured for rack mounting within enclosures for electrical components.

Abstract: A spring probe block assembly includes an insulative housing. A probe connector having a signal probe, an insulative layer, and a conductive shell is positioned within the housing. At least one ground probe is also positioned within the housing. The ground probe and the conductive shell of the probe connector are electrically connected by a grounding element. The grounding element is configured to elastically deform the ground probe in such a manner as to create spring energy in the ground probe. The spring energy generates a normal force between the ground probe and the grounding element which maintains the ground probe in its position. Also, a method for retaining a spring probe in a housing by elastically deforming the spring probe to maintain a spring force between the spring probe and the housing.

Abstract: A method of making a three dimensional optical circuit featuring an optical manifold for organizing, guiding and protecting individual optical fibers is provided. One aspect of the present invention is a three dimensional manifold which may be constructed using a rapid prototyping process such as, but not limited to, stereolithography (“SLA”), fused deposition modeling (“FDM”), selective laser sintering (“SLS”), and the like. The manifold has a number of input openings in a first ordered arrangement at one end connected by passageways to a number of output openings in a second ordered arrangement at the opposite end. A plurality of optical fibers may be directed through the passageways of the manifold to produce a three dimensional optical circuit such as a shuffle.

Abstract: A front projection screen and associated system and method are disclosed that utilize a back structured layer and a front diffusing layer to provide improved viewable image quality. The structured layer is formed with a plurality of grooves and can operate to direct light into a defined audience view region. The diffusing layer is coupled to the structured layer and is formed from a matte polyester film to provide dry erase capability on a front surface of the diffusing layer. For example, the matte polyester film can be TEKRA Marnot XL matte Melinex polyester film. Further, the structured layer can be formed as an acrylate linear prismatic structure having a gloss white coating. The acrylate linear prismatic structure and the matte polyester film can be coupled, for example, by lamination or can be coupled by being extruded as a unitary construction.

Abstract: An electrical connector for terminating a shielded cable and connecting the cable to regularly arranged contact pins. The connector includes a connector body formed from an insulative material. The connector body has an upper surface and an opposing lower surface defined by a front edge, a back edge and two longitudinal side edges. The upper surface includes a plurality of longitudinal channels adapted to receive a plurality of socket contacts. A planar conductive ground plate engages the bottom surface of the connector body and extends across each of the plurality of socket contacts to establish a ground plane across the entire connector. A cover member encloses the longitudinal channels and socket contacts. A plurality of individual connectors may be stacked together and retained in a stack by a removable retaining rod.

Abstract: A method for measuring the absolute throughput of a polarization modulating reflective display in an optical system having a folded light path. The steps include measuring a first light intensity, LR, in the folded light path, having a first polarizing beam splitter, and a reflective display. A second intensity, LO, is measured using an unfolded light path where the reflective display is replaced by a second cross-rotated polarizing beam splitter. The absolute throughput is TM is calculated, where TM=LR/LO.

Abstract: A front projection system and associated method are disclosed that correct distortion for a front projector device. The front projector device is characterized by off-axis optics and a throw-to-screen diagonal ratio of at most 1 which generate distortion including pincushion, keystone and anamorphic distortion components. Further, the projection device has an electronic distortion correction component operable to pre-distort an image prior to projection in order to correct for the pincushion, keystone and anamorphic distortion components of the projector device. Further, an associated method is also disclosed for correcting distortion generated in a projection system by a combination of optical and electronic correction. The method comprises setting a limit on the amount of image information that is acceptable to lose through the optical components, and selecting an optical solution is comprising optics having inherent distortion within the set limit.

Abstract: An optical imaging system including a wide-angle Cartesian polarizing beam splitter, light valve illumination optics having an f/#≦2.5, and at least one reflective light valve. The Cartesian polarizing beam splitter (PBS) has a structural orientation defining fixed polarization axes. The use of a Cartesian PBS allows the development of systems using curved PBS that provide higher light output and/or replace or augment other optical components. By recognizing and advantageously applying properties of wide-angle Cartesian polarizers, the present invention discloses a high-efficiency optical imaging system capable of functioning at f/#'s equal to or below f/2.5 while maintaining a contrast ratio of at least 100 to 1, or, more preferably, 150 to 1 in a projection system configuration.

Abstract: An integrated front projection system has a housing assembly, a projection assembly, and an expansion assembly. The housing assembly includes a frame having a front surface that provides a front projection screen and contains other modular components. In addition, a projection assembly with a movable arm may be included, having a storage position and a projection position, and to which the front projection head may be coupled. According to one aspect, the projection assembly is modularized and has a plurality of easily replaceable component modules coupled to the housing and which operate together to project an image onto the front projection screen. According to another aspect, the integrated front projection system further has an expansion assembly coupled to the housing. The expansion assembly includes an expansion slot formed in the housing and electrically coupled to a display controller in the projection assembly and expansion modules coupled to the expansion slot.

Abstract: A liquid ink repellent coating adapted to prevent transfer of fluid image forming ink droplets between imaged sheets in a stack of multiple printed impressions. The repellent coating comprises a polymeric composition having a surface energy less than about 30 mJ/m2 and an insoluble particulate filler as a matting agent.

Abstract: The present invention provides an image-recording transparent film having a toner-fixing layer which shows an improved compatibility with a toner resin, and capable of forming a color image of high quality. An image-recording transparent film comprising a transparent substrate and a toner-receiving layer provided at least on one major surface of the substrate, the toner-receiving layer comprising a light-transmitting resin having a softening point of 90 to 180° C., and from 0.1 to 40 parts by weight of an amide nonionic surfactant based on 100 parts by weight of the light-transmitting resin which surfactant is in a compatible state with the light-transmitting resin.

Abstract: A converter for terminating a coaxial connector to a coaxial cable when the cable shield layer outer diameter is larger than an interior dimension of the connector shell. The converter includes a conductive shell having a first end and a second end. The first end of the converter shell has an inner diameter larger than the outer diameter of the cable conductive shield layer, and the second end of the converter shell has an outer diameter smaller than the interior dimension of the connector shell. A dielectric insulation insert is positioned with the converter shell. The converter may be designed to match the impedance of either the coaxial cable or the connector, or the converter may smoothly transition from the impedance of the cable to the impedance of the connector.

Abstract: A spring probe block assembly includes an insulative housing. A probe connector having a signal probe, an insulative layer, and a conductive shell is positioned within the housing. At least one ground probe is also positioned within the housing. The ground probe and the conductive shell of the probe connector are electrically connected by a grounding element. The grounding element is configured to elastically deform the ground probe in such a manner as to create spring energy in the ground probe. The spring energy generates a normal force between the ground probe and the grounding element which maintains the ground probe in its position. Also, a method for retaining a spring probe in a housing by elastically deforming the spring probe to maintain a spring force between the spring probe and the housing.

Abstract: An overhead projector including a stage assembly, a post extending from the stage assembly and an optical projection head assembly suspended above the stage assembly by the post in a cantilever arrangement, the optical head assembly having a weight W. The head assembly includes a post retaining assembly having a collar fitted around the post, the collar having at least two friction points interacting with the post, the interaction having a coefficient of friction &mgr;. The weight W and the cantilever arrangement create torsional forces, the at least two friction points being positioned to transmit the torsional forces onto the post creating a friction force Ff. The coefficient of friction of the interaction between each of the at least two friction points and the post is selected such that absent other forces the friction force is at least sufficient to maintain the head assembly at a static position with respect to the post.

Abstract: A process for making a retroreflective article that includes the steps of providing a device (tool or a mold) having a first structured surface; applying a reflective layer on the first structured surface resulting in a first adhesion value between the reflective layer and the first structured surface, the reflective layer having an exposed surface; applying a molding polymer to the exposed surface of the reflective layer resulting in a second adhesion value between the reflective layer and the molding polymer. The second adhesion value is higher than the first adhesion value. The device is separated from the molding polymer to yield a retroreflective article that has a second structured surface that is the reverse image of the first structured surface. The separation causes a transfer of the reflective layer from the first structured surface to the retroreflective article.