Abstract: A prismatic lighting panel of very low weight (less than four ounces per square foot), high strength, and good optical characteristics includes a grid of depending thin ribs on one inch centers, and a web of microprisms between the ribs.

Abstract: A lighting panel has a planar upper face and a lower face having a system of aspherical female lenticules arranged in an overlapping offset pattern to form a network of diamond-shaped domed cells. The panel provides adequate light control and may be made thinner than a panel having female conical prisms. The panel also is substantially lighter weight than a panel of equivalent thickness having conical prisms, over a wide range of thicknesses. The pattern allows panels having a wide range of thicknesses to be made from the same tooling.

Abstract: A lighting system for providing aesthetic and energy efficient lighting, for building interiors and exterior lighting, includes lighting fixtures including a high intensity discharge lamp and a novel lens. The lens is formed as a dropped square pyramid with four triangular lower panels and four generally vertical side walls. Prisms on the inner and outer faces of the lens produce a higher luminous intensity at an angle of about 30.degree. to 50.degree. than at nadir and project light at higher angles toward the corners of the lens than perpendicular to the sides of the lens, thereby producing a generally square, widespread light distribution pattern. The lens cuts off high angle light (with respect to nadir), thereby reducing glare.

Abstract: Storm window framing, including a tape frame having a tape-receiving channel defined by spaced, parallel inner and outer ribs and one surface of a connecting web, a pane-receiving channel and a seat boss, the seat boss including a pair of spaced jaws defining between them a seat boss channel, keyhole-shaped in transverse section and with an outwardly opening, outwardly flaring mouth, and a glazing frame having a tenon strip with a head and neck adapted to fit in the keyhole-shaped seat boss channel and a root flared complementarily to and adapted to fill the mouth of the tape frame seat boss channel when the head and neck are fully seated, and, integral with and cantilevered from the root, a pane biasing leaf strip, extending at an angle toward the pane-receiving channel of the tape frame.Preferably, the full framing includes a sill section, extending along a lower edge of a pane and engaging a window sill.

Abstract: A light-weight plastic lighting panel having recessed conical prisms arranged in such a way that their intersecting edges form equilateral triangles, all of whose sides lie along lattice lines. The side of each triangle has a length of 0.475 cm. (three-sixteenths of an inch), and the panel may have a weight of less than 1600 grams per square meter (5.2 ounces/square foot).

Abstract: Luminaires equipped with an improved high efficiency, wide light distribution lighting panel provide more favorable ESI values and may be spaced farther apart than conventional ones. The lighting panel includes three bands of conical prismatic elements; these bands are spaced on 5-inch centers from each other and are separated by substantially transparent bands having shallow 15.degree. flutes to soften the lamp images. Outside the bands of conical prisms are bands of lengthwise elevating prisms for increasing the spread of light to the sides of the fixture. Outside the elevating bands are bands of lengthwise depressing prisms. A single panel design provides similar excellent optical characteristics for either a two-lamp or three-lamp troffer.