Abstract: A lighting device comprises a plurality of light sources (61) fixedly mounted on a support. At least one of the light sources is operable independently of the other light source(s), and optionally every one of the light sources is operable independently of every other light source. The lighting device has an optical system (62) for directing light from each light source along respective directions different from one another. The axes and illumination patterns of the optical system subscribe 360° in the plane of the lighting device. The lighting device is preferably operable in at least a first mode in which the lighting device provides directional lighting and a second mode in which the illumination provided by the lighting device subscribes substantially 360° in the plane of the lighting device.

Abstract: A light guide plate includes a first major surface, a second major surface opposite the first major surface, and a pair of opposite primary side surfaces and a pair of opposite secondary side surfaces that are perpendicular to the first and second major surfaces. The light guide plate further includes a plurality of pairs of opposing grooves including a first groove provided on the first major surface and a second groove provided on the second major surface. The light guide plate further includes a plurality of light sources configured relative to the grooves. A backlight unit includes the described light guide plate fixed to a back plate. A liquid crystal display device includes the backlight unit positioned behind a liquid crystal panel.

Abstract: A backlight unit includes a light source and at least one modular light guide plate (LGP) element that guides light from the light source. The modular LGP element has a first surface and a plurality of pins integrally formed with and protruding from the first surface. A back plate portion has a plurality of receptacles for receiving the plurality of pins of the modular LGP element to fix the modular LGP element to the back plate portion. A backlight includes a plurality of the described backlight units, wherein the modular LGP elements are arranged in a two dimensional array, and the back plate portions form a common back plate to which the modular LGP elements are fixed. The backlight including the described backlight units may be incorporated into a liquid crystal display device.

Abstract: A concentrated photovoltaic system includes a photovoltaic cell; a primary light concentrating optic; and a secondary light mixing concentrator. The primary light concentrating optic is arranged to collect solar radiation and concentrate the collected solar radiation towards the secondary light mixing concentrator. The secondary light mixing concentrator is arranged to concentrate the concentrated solar radiation from the primary light concentrating optic towards the photovoltaic cell. The secondary light mixing concentrator includes a dielectric member having first and second primary surfaces, with the second primary surface being in optical contact with the photovoltaic cell and the first primary surface facing the primary light concentrating optic. The first primary surface has a non-planar surface structure configured to redirect light which is reflected at transitional surfaces between the secondary light mixing concentrator and the photovoltaic cell back towards the photovoltaic cell.

Abstract: A display backlight comprises a light guide plate (12b) and independent controllable light sources (10, 11). The plate (12b) is divided into first and second regions (13, 14) having light extraction features, such as corrugations, which direct light travelling in first and second directions, respectively, through the plate out of its front major surface and transmit light travelling in the second and first directions, respectively.