Abstract: A suspended lighting fixture for direct/indirect lighting having a broad light emitting surface and including a thin curved sheet of an optically transmissive material, an LED strip optically coupled to a light input edge of the curved sheet, one or more suspension elements, an elongated heat dissipating structural element longitudinally extending along the light input edge, and an opaque elongated housing at least partially enclosing the LED strip. The curved sheet may include forward-deflecting or forward-scattering elements distributed over an area of the curved sheet according to a two-dimensional pattern and configured to extract light from one location of the sheet and direct the extracted light toward a second location of the sheet.

Abstract: An illumination system having a plurality of light emitting diodes (LEDs) and multiple layers of optical elements used to distribute light emitted by the LEDs. The optical elements may include a planar optical waveguide, a plurality of non-imaging lenses, a two-dimensional pattern of light extraction elements, a reflective surface, a light diffusing layer. The illumination system may further have a plurality of luminescent centers distributed in a volume of a planar layer of an optically transmissive material or one or more light converting elements used for converting light.

Abstract: A foldable electronic display having a layered sheet-form structure including a multi-layer flexible support substrate sheet, a flexible front sheet and a plurality of rigid heat-conductive substrates bonded to the flexible support substrate sheet, and a large number of individually digitally addressable solid-state light emitting devices hermetically encapsulated within the layered sheet-form structure and each configured to emit light in a different color than an adjacent solid-state light emitting device. The display further has a fold area located in a space between at least two of the plurality of rigid heat-conductive substrates and is configured for repetitive and reversible folding upon itself with a radius of curvature in the fold area from 1 mm to 5 mm.

Abstract: A method of making an angular selective light control sheeting is disclosed. The method includes providing a sheet of an optically transmissive elastic material, providing a slitting blade, advancing the slitting blade into the optically transmissive elastic material to a predetermined depth, moving the slitting blade relatively to the sheet along a straight or curvilinear path so as to form a channel in the elastic material, and introducing an opaque material into the channel.

Abstract: Light directing film structure employing at least two layers having different refractive indices and forming a continuous corrugated boundary between major surfaces of the film. The corrugated boundary forms a plurality of alternating facets forming different dihedral angles with a prevalent plane of the film structure. The facets may longitudinally extend along an arcuate or circular path. Light received by a major surface of the film structure is internally redirected by interacting with the facets of the corrugated inter-layer boundary and may be emitted from the opposing major surface towards a new propagation direction which is different from the original propagation direction.

Abstract: A method of forming a structurally reinforced illumination panel which includes providing a multiwall structural panel having a pair of optically transmissive sheets joined with transverse ribs that define a plurality of linear hollow chambers, providing LED strips each including a plurality of interconnected LED sources distributed over a length the LED strip, a step of inserting the LED strips into the linear hollow chambers through open ends of the chambers, and a step of electrically connecting the LED strips to a power supply.

Abstract: A stepped light guide illumination system employing a planar sheet of an optically transmissive material having a stepped light guiding structure including one or more parallel arrays of channels. Light is input into the stepped light guiding structure using a number of light sources, such as LEDs, located within the channels and coupled to the stepped light guiding structure at multiple locations. Light is extracted from the stepped light guiding structure by two-dimensional patterns of light extraction features provided in surface areas of the stepped light guiding structure located between the parallel channels.

Abstract: A retroreflective sheeting which comprises a top transmissive layer including a plurality of parallel channel formed perpendicular to a surface of the layer, and a reflective bottom layer including a specular surface or a corrugated transmitting surface. The corrugated surface includes a plurality of linear prismatic elements extending perpendicular to the channels of the top layer. The top and bottom layers reflect light in orthogonal directions and act cooperatively to retroreflect incident light back toward the source, particularly at high incidence angles.

Abstract: A method of making multi-layer light converting optical structures including providing an artificial light source, an optically transmissive sheet having a parallel array of linear grooves, a reflective back cover sheet, and a planar light converting layered structure which is approximately coextensive with the planar optically transmissive sheet. The light converting layered structure includes a partially transmissive layer of a light absorbing medium sandwiched between two transparent layers. The light absorbing medium includes light absorbing elements distributed in a volume of an optically transmissive material and configured to absorb light in a first wavelength more weakly than in a second wavelength. The method further includes positioning the light converting layered structure between the planar optically transmissive sheet and the reflective back cover sheet for enhanced light trapping and conversion.

Abstract: An illumination system employing a waveguide that receives and propagates light in response to transmission and total internal reflection. Light deflecting elements distributed along the propagation path incrementally change the out-of-plane angles of light rays and cause decoupling of portions of light from the waveguide at different distances from the light input edge or end. Light may escape from the waveguide into an intermediate layer at low out-of-plane angles and can be further redirected by light extraction features out of the system. In one embodiment, the illumination system is configured to emit collimated light. In one embodiment, the illumination system includes shallow surface relief features. In one embodiment, the light deflecting elements include forward-scattering particles distributed throughout the volume of the waveguide.

Abstract: A light converting optical system employing a planar light trapping optical structure illuminated by a source of monochromatic light. The light trapping optical structure includes a photoresponsive layer including quantum dots. The photoresponsive layer is configured at a relatively low thickness and located between opposing broad-area reflective surfaces that confine and redistribute light within the light trapping structure, causing multiple transverse propagation of light through the photoresponsive layer and enhanced absorption and light conversion. The light trapping optical structure further incorporates optical elements located on a light path between the light source and the photoresponsive layer.

Abstract: An apparatus for distributing light from a planar waveguide through an array of linear cylindrical lenses formed in a major surface of the waveguide, and a method of making the same. Light received on an edge of the waveguide is propagated transmissively and retained by total internal reflection, except in response to impinging upon light deflecting elements which sufficiently redirect the light to escape the waveguide such that the extracted from the waveguide is further redirected and redistributed through the array of linear cylindrical lenses.

Abstract: Electronic displays having curved or retractable configurations and having a layered monolithic sheet-form structure including a bottom heat conductive layer, a top optically transmissive layer coextending with the bottom layer, and a two-dimensional array of individually digitally addressable solid-state illumination devices such as LEDs or OLEDs. The top and bottom layers hermetically encapsulate the array of individually digitally addressable solid-state illumination devices.

Abstract: Light directing film structure employing at least two layers having different refractive indices and forming a continuous corrugated boundary between major surfaces of the film. The corrugated boundary forms a plurality of alternating facets forming different dihedral angles with a prevalent plane of the film structure. The facets may longitudinally extend along a straight, arcuate, circular, or curvilinear path. Light received by a major surface of the film structure is internally redirected by interacting with the facets of the corrugated inter-layer boundary and may be emitted from the opposing major surface towards a new propagation direction which is different from the original propagation direction.

Abstract: Wide-area solid-state illumination devices and systems employing a light guide formed by a sheet of an optically transmissive material and selectively patterned in designated areas. Printed light extraction features are used to form a plurality of patterned areas are separated from each other and from edges of the light guide by separation areas which are generally free from the light extraction features. One or more light emitting diodes (LEDs) is optically coupled to the light guide and provides a light source. The light guide is sandwiched between a front sheet and a reflective back sheet. The front sheet includes opaque areas and a plurality of optically transmissive areas disposed in registration with the patterned areas.

Abstract: A light trapping optical structure employing an optically transmissive layer with a plurality of light deflecting elements. The transparent layer is defined by opposing broad-area surfaces extending parallel to each other. The light deflecting elements deflect light propagating transversely through the optically transmissive layer at a sufficiently high bend angle with respect to a surface normal, above a critical angle of a Total Internal Reflection. The deflected light is retained by means of at least TIR in the system which allows for longer light propagation paths through a photoabsorptive layer that may be associated with the optically transmissive layer for an improved light absorption. The light trapping optical structure may further employ a focusing array of light collectors being pairwise associated with the respective light deflecting elements.

Abstract: A stepped light guide illumination system employing a planar sheet of an optically transmissive material having a stepped light guiding structure including one or more parallel arrays of channels. Light is input into the stepped light guiding structure using a number of light sources, such as LEDs, located within the channels and coupled to the stepped light guiding structure at multiple locations. Light is extracted from the stepped light guiding structure by two-dimensional patterns of light extraction features provided in surface areas of the stepped light guiding structure located between the parallel channels.

Abstract: A window covering for natural illumination of building interiors by redirecting the incident daylight at angles that promote its deeper penetration into the interior space. The window covering comprises an optically transmissive, flexible polymeric sheet having a layered structure with a light diffusing output surface and a number of total internal reflection surfaces incorporated into its material. The total internal reflection surfaces are dimensioned such that the multi-layer sheet diffusely redirect at least a portion of light towards a direction which is generally not coincident with the incidence direction.

Abstract: Wide-area solid-state illumination devices and systems employing a thin and flexible sheet of an optically transmissive material having at least one broad-area surface patterned with light scattering surface microstructures such as microdots of a non-absorbing UV curable ink. Light is input into the thin and flexible sheet using a number of compact solid-state light sources, such as LEDs, optically coupled to one or more edges or to one or two of the broad-area surfaces defining the thin and flexible sheet. Each surface microstructure forms a semi-opaque layer that extracts light from the thin and flexible sheet and causes light emission from both opposing broad-area surfaces of the sheet.

Abstract: An illumination system employing an elongated waveguide having a non-round transversal cross-section and having at least a portion of its surface shaped in the form of a linear collimating element. The waveguide further employs at least one array of light extracting features distributed along a longitudinal axis of the waveguide and disposed in the focal area of the respective linear collimating element. Each light extracting feature has an active aperture which is substantially less than the light receiving aperture of the linear collimating element and is configured to redirect light propagating in the waveguide generally towards a normal direction with respect to the longitudinal axis of the waveguide. Light rays redirected by the light extracting features are further collimated by the linear collimating element and exit from the waveguide in the form of a directional beam.