Abstract: A low reflectivity, variable attenuation contrast enhancement filter having a total visible light reflectance of less than about 2.0% when measured with light incident to the first outer major surface. The contrast enhancement filter has a first layer(s) for providing antireflection, the first layer(s) defining the first outer major surface; a variable attenuation element interposed between the first major outer surface and the second major outer surface; element(s) for providing fixed attenuation interposed between the variable attenuation element and the first major outer surface; and at least one substrate.

Abstract: An optical filter screen for a visual display monitor includes an optical filter supported by a support frame. A pair of adjustable mounting members support the support frame from a visual display monitor or similar such that the optical filter is positioned adjacent a display area of the display monitor. Each mounting member includes a stem element with a first and second end. A support element is rotatably engaged with the first end of the stem element so that in a first stop position the support element extends outwardly from the stem element to engage a top surface of the visual display unit. The support element folds down into a second storage position in which it lies substantially parallel with the stem element.

Abstract: A louvered plastic film has louvers including central regions with a relatively high coefficients of extinction and outer regions with relatively low coefficients of extinction. Such a film provides a dramatic reduction in ghost images.

Abstract: An optical filter screen for a visual display monitor includes an optical filter supported by a support frame. A pair of adjustable mounting members support the support frame from the visual display monitor such that the optical filter is positioned adjacent a display area of the display monitor. Each mounting member includes a latch member that is movable between an unlatched state wherein the filter can be moved relative to the display area of the display monitor and a latched state wherein the filter is held in a desired position relative to the display area. Each mounting member further includes a movable latch operator for moving the latch member between the latched state and the unlatched state.

Abstract: A passive railroad crossing warning device has two input optical windows that receive light from the headlight of an oncoming locomotive. The light is redirected to an output optical window where a combiner causes it to exit at a predetermined angle to make it visible to motorists approaching the railroad crossing.

Abstract: An optical filter screen for a visual display monitor includes an optical filter supported by a support frame. A pair of adjustable mounting members support the support frame from the visual display monitor such that the optical filter is positioned adjacent a display area of the display monitor. Each mounting member includes a latch member that is movable between an unlatched state wherein the filter can be moved relative to the display area of the display monitor and a latched state wherein the filter is held in a desired position relative to the display area. Each mounting member further includes a movable latch operator for moving the latch member between the latched state and the unlatched state.