Abstract: A skylight for a building includes a solar panel arranged within the skylight, the solar panel comprising one or more photovoltaic cells to collect direct radiation from rays of sunlight for conversion to electrical power, and an optical element to receive the direct radiation and refract it to the solar panel, and to receive the direct radiation and diffuse radiation scattered from the rays of sunlight and refract the direct radiation and the diffuse radiation through the skylight, bypassing the solar panel, to provide daylighting in the building.

Abstract: A multi-power source system including a first power source, a second power source in a parallel with the first power source, and a diode preventing power from the second power source to drive the first power source, but permitting the first power source to charge the second power source. The system also includes a controller operably coupled to both the first and second power sources, and a plurality of field effect transistor (FETs) arranged in series with one or more of the first power source, the second power source, and the load, wherein controller can switch the plurality of FETs to enable the first power source to drive the load or the second power source to drive the load.

Abstract: A skylight for a building includes a solar panel arranged within the skylight, the solar panel comprising one or more photovoltaic cells to collect direct radiation from rays of sunlight for conversion to electrical power, and an optical element to receive the direct radiation and refract it to the solar panel, and to receive the direct radiation and diffuse radiation scattered from the rays of sunlight and refract the direct radiation and the diffuse radiation through the skylight, bypassing the solar panel, to provide daylighting in the building.

Abstract: A multi-power source system including a first power source, a second power source in a parallel with the first power source, and a diode preventing power from the second power source to drive the first power source but permitting the first power source to charge the second power source. The system also includes a controller operably coupled to both the first and second power sources, and a plurality of field effect transistor (FETs) arranged in series with one or more of the first power source, the second power source, and the load, wherein controller can switch the plurality of FETs to enable the first power source to drive the load or the second power source to drive the load.

Abstract: There is provided a therapeutic method and system for utilizing full spectrum of natural solar radiations with an optimum balance of ultra-violet (UV), visible and infrared (IR) radiations. The disclosed therapeutic method comprising collecting and concentrating the natural solar radiations using a natural solar radiations concentrator; transporting the concentrated natural solar radiations using a transporting medium to an indoor device; optimizing a spot size, an intensity and an ultra-violet range of the natural solar radiations; and directing the optimized natural solar radiations to a desired body part using the indoor device; wherein the full spectrum of natural solar radiations has an optimum balance of ultra-violet, visible and infrared radiations.

Abstract: The present disclosure describes thermally insulating glass laminates that mitigate or prevent heat loss from heated cavities. In some embodiments, the thermally insulating glass laminates comprise a non-uniform low or non-conductive coating layer that forms a chemical bond with at least one inner surface of the substrates, wherein the coating layer can have a thickness of about 0.010 inches or less and forms a pattern that contacts about 30% or less of at least one inner surface of a substrate and helps form a plurality of sealed cavities of gas molecules between the substrates. Since there is a small amount of gas molecules in each cavity, convective heat transfer between the substrates is minimized thereby minimizing heat loss through the laminates into the surrounding environment.

Abstract: A solar tracker apparatus includes an adjustable hanger assembly that has a clam shell hanger assembly. The clam shell hanger assembly may hold a torque tube comprising a plurality of torque tubes configured together in a continuous length from a first end to a second end. A center of mass of the solar tracker apparatus may be aligned with a center of rotation of the torque tubes, in order to reduce a load of a drive device operably coupled to the torque tube. Solar modules may be coupled to the torque tubes. The solar tracker includes an energy system that includes solar panel, a DC to DC converter, a battery, and a micro-controller. The energy system may facilitate full operation movement of the tracker apparatus without any external power lines.

Abstract: Lighting devices and methods for providing daylight to the interior of a structure are disclosed. Some embodiments disclosed herein provide a daylighting device including a tube having a sidewall with a reflective interior surface, a light collecting structure, and a light reflector positioned to reflect daylight into the light collector. In some embodiments, the light collector is associated with one or more light-turning and/or light reflecting structures configured to increase the amount of light captured by the daylighting device. Optical elements may allow for the absorption and/or selective transmission of infrared light away from an interior of the daylighting device.

Abstract: A hybrid lighting system is disclosed in which light emitting diodes (LEDs) provide input light when illumination with solar light is unavailable. Light from LEDs are propagated through an optical fiber, which delivers the light to a point of illumination. The disclosed system reduces the amount of electricity and electric conduit for light in areas using hybrid lighting systems.

Abstract: A sensing device with a glare shield has an infrared sensor and a glare shield. The infrared sensor has a body and a lens hood. The lens hood is mounted around an outer periphery of the body. The glare shield is conical, is detachably mounted around the lens hood of the infrared sensor, and extends in a direction away from the body of the infrared sensor. The glare shield prevents the infrared sensor from being affected by glare emitted from adjacent lighting devices. Accordingly, the sensing device avoids incorrect judgment of environmental luminance caused by lighting devices nearby and therefore generates less misoperation, so that the goal of being more power-saving can be achieved.

Abstract: A multi-mode lighting system includes a collector unit having a base including a cavity and a transparent or translucent cover mounted on the base. The system further includes a lighting module having a base, a transparent or translucent cover and a photovoltaic element mounted therein. A plurality of fiber optic filaments extend from the collector to the lighting module to transmit radiation from first ends of the fiber optic filaments to second ends of the fiber optic elements. The first ends of the fiber optic filaments are disposed in an array in the collector unit to receive radiation and second ends are disposed in an array in the lighting module to emit radiation received by the first ends of the fiber optic filaments. Radiation transmitted by the fiber optic filaments illuminates an area external to the lighting module and impinges the photovoltaic element to generate electricity.

Abstract: An optical distributor (10) is formed as a reflector with one or more sloping surfaces. The sloping surfaces have varying angles of inclination from a bottom edge (20) to a top edge of the reflector. The sloping surfaces may form a substantially pyramidal or conical frustum-shaped surface. The sloping surfaces may additionally or alternatively form a band of adjacent or contiguous faceted surfaces. The reflector is configured to receive light rays through an opening (32) in a first plane (30) and reflect light rays radially outward and upward at varying angles of reflection (8B) to a bottom surface of the first plane (30) in a manner that illuminates both the bottom surface of the first plane (30) and an area (40) below the first plane (30). The reflected light may illuminate the first plane (30) and the area (40) below in a substantially uniform manner.

Abstract: A solar light distribution system includes a solar light concentrator that is affixed externally to a light transfer tube. Solar light waves are processed by the concentrator into a collimated beam of light, which is then transferred through a light receiving port and into the light transfer tube. A reflector redirects the collimated beam of light through the tube to a light distribution port. The interior surface of the light transfer tube is highly reflective so that the light transfers through the tube with minimal losses. An interchangeable luminaire is attached to the light distribution port and provides light inside of a structure. A sun tracking device rotates the concentrator and the light transfer tube to optimize the receiving of solar light by the concentrator throughout the day. The system provides interior lighting that uses only renewable energy sources, and releases no carbon dioxide emissions into the atmosphere.

Abstract: Lighting devices and methods for providing daylight to the interior of a structure are disclosed. Some embodiments disclosed herein provide a daylighting device including a tube having a sidewall with a reflective interior surface, a light collecting structure, and a light reflector positioned to reflect daylight into the light collector. In some embodiments, the light collector is associated with one or more light-turning and/or light reflecting structures configured to increase the amount of light captured by the daylighting device. Optical elements may allow for the absorption and/or selective transmission of infrared light away from an interior of the daylighting device.

Abstract: A solar light distribution system includes a solar light concentrator that is affixed externally to a light transfer tube. Solar light waves are processed by the concentrator into a collimated beam of light, which is then transferred through a light receiving port and into the light transfer tube. A reflector redirects the collimated beam of light through the tube to a light distribution port. The interior surface of the light transfer tube is highly reflective so that the light transfers through the tube with minimal losses. An interchangeable luminaire is attached to the light distribution port and provides light inside of a structure. A sun tracking device rotates the concentrator and the light transfer tube to optimize the receiving of solar light by the concentrator throughout the day. The system provides interior lighting that uses only renewable energy sources, and releases no carbon dioxide emissions into the atmosphere.

Abstract: A solar simulator including a light source and a light conduit array is provided. The light source is used for emitting a beam of ray radiation. The light conduit array includes a plurality of light conduits closely adjacent to one another. Each of the light conduits has an inner reflecting surface used for reflecting the ray radiation, a light input side, and a light output side opposite to the light input side. The ray radiation enters the light conduits through the light input side and emitting from the light output side.

Abstract: The disclosed subject matter is a reflector assembly for a skylight curb and the method of installing same through a safety grid from the roof. The purpose of the disclosed subject matter is to improve the optical performance of skylight curbs. The reflector assembly is manufacture from metallized polymer film, trimmed to match the desired interior curb surface where it will be mounted, and equipped with attachment devices to facilitate installation. The reflector assembly is configured by folding or rolling into a compact shape, passing it through an opening in the safety grid, unfolding it, and securing it in its proper position using the integrated attachment devices.

Abstract: Certain disclosed embodiments provide internally-reflective tube assemblies for use in a tubular daylighting device configured to direct daylight into an interior of a building when installed on a roof of the building. A tube assembly may include multiple tube segments including connection projections, such as hook-type structures, for weaving or otherwise connecting and/or securing tube segments together. In some embodiments, sidewalls of tube segments connected together are substantially parallel to one another at or near the connection region.

Abstract: The present invention relates to a light redirection device (1) for redirecting and concentrating direct sunlight (31) into buildings, said device comprising at least one transparent element (10) having a substantially planar top surface (10) in an x-y-plane and a substantially planar bottom surface (14), wherein said top (11) and bottom (14) surfaces are arranged in an angle ? to each other around the x-axis, and a light reflector (20) for each transparent element (10) having a planar surface, wherein said planar surface of said light reflector (20) is arranged substantially parallel and adjacent said bottom surface (14) of said transparent element (10), wherein said reflective surface is spaced apart (12) from said transparent element by a transparent medium having lower refractive index than the transparent element (10), so that incident light (31) to the device is refracted by each material transition interface and reflected by the reflecting element (20).

Abstract: A sheet-form light-redirecting optical article for illuminating building interiors with sunlight. At least one embodiment comprises a sheet of optically transmissive rigid material, preferably Poly(methyl methacrylate), in which a plurality of deep and narrow parallel channels are formed and arranged in two perpendicular arrays. Each channel has opposing walls configured for reflecting light by means of a Total Internal Reflection (TIR). At least a portion of off-axis rays incident onto the surface of the sheet is redirected by the TIR walls of the light-guiding channels. At least one embodiment comprises a grid formed by intersecting specular reflectors and further comprises a light diffusing element optically coupled to the grid. Disclosed also are a method for making the intersecting arrays of light-redirecting channels.

Abstract: The disclosure generally relates to concentrating daylight collectors and in particular to concentrating daylight collectors useful for interior lighting of a building. The concentrating daylight collectors generally include a cassegrain-type concentrator section that provides for a full-tracking solar collector with one moving part and with a high efficiency of coupling of collected solar irradiation to a stationary duct. In some cases, the disclosed concentrating daylight collectors can be used more conventionally, such as for directing sunlight onto a photo-voltaic cell for generation of electrical power, or an absorbing surface for extraction of thermal energy.

Abstract: Sunlight redirector (30) incorporates closely proximate mirror arrays (32, 34) having parallel, uniformly spaced, longitudinal mirror segments (38, 44). Prismatic sheet (36) is positioned behind and closely proximate second array (34). Segments (38) extend in first direction (x). Segments (44) extend in second direction (y) perpendicular to direction (x) segments (38, 44)have normal vectors (42, 48). Segments (38) are interconnected for simultaneous pivotal movement (40), such that their normal vectors (42) remain parallel. Segments (44) are interconnected for simultaneous pivotal movement (46), such that their normal vectors (48) remain parallel. Arrays (32, 34) redirect incident light toward sheet (36), which redirects the light into a desired fixed direction, e.g. parallel to the sunlight redirect's normal vectors (50). Segments (38, 44) may have inward and outward segments (60A, 60B) which can be adjustably positioned to maximize redirection of incident sunlight rays in a desired direction.

Abstract: A light collecting and disseminating apparatus is provided for use in harvesting sunlight from the exterior of a man-made structure, and providing light to the inside of the structure, via an opto-mechanical joint where sunlight would not normally be available. The internal arrangement of the collector allows for improved optical accuracy and performance over prior efforts. The apparatus is also characterized as possessing a low profile so as not to alter the appearance of buildings furnished with the invention. Further, light can be collected from any orientation and redirected through the opto-mechanical joint to a stationary light receiving port independent of the orientation of the collectors.

Abstract: A method and device for improving natural lighting within buildings is provided. The device comprises a controllable shelf having an upper, specular reflective surface for directing natural light into interior spaces and against interior ceilings. The shelves can be static or pivotable to redirect light based on the day and time of year. The pivotable shelf can be rotated downward or upwards to change the angle with which the light is reflected into the adjacent window, while its position is below the window and along the exterior of the building. This improves interior natural lighting and reduces electrical lighting costs using either a static shelf or movable shelf, wherein the assembly is deployable in a commercial or residential environment without blocking any naturally entering light through the window itself.

Abstract: Attachment methods for daylighting sheets and a resulting optical construction enable daylighting microstructures to be secured to a light incident surface, such as a glazing. Applying an adhesive to selected portions of the daylighting microstructures creates a transparent, optical adhesive surface that enables the daylighting microstructures to be oriented outward, facing the incident light, and effectively seals the microstructures against the glazing to prevent ingress of dust and contaminants that would degrade optical efficiency.

Abstract: Thermochromic filters use combinations of absorptive, reflective, thermoabsorptive, and thermoreflective elements covering different portions of the solar spectrum, to achieve different levels of energy savings, throw, shading, visible light transmission, and comfort. Embodiments include stopband filters in the near-infrared spectrum.

Abstract: Certain disclosed embodiments provide internally-reflective tube assemblies for use in a tubular daylighting device configured to direct daylight into an interior of a building when installed on a roof of the building. A tube assembly may include multiple tube segments including connection projections, such as hook-type structures, for weaving or otherwise connecting and/or securing tube segments together. In some embodiments, sidewalls of tube segments connected together are substantially parallel to one another at or near the connection region.

Abstract: Lighting devices and methods for illuminating the interior of a building with natural daylight are disclosed. In some embodiments, a daylighting apparatus includes a tube having a sidewall with a reflective interior surface, an at least partially transparent light collector with one or more light turning elements, and a light reflector positioned to reflect daylight into the light collector. The one or more light turning elements can turn direct and indirect daylight into the tube so that it is available to illuminate the building. In some embodiments, the tube is disposed between the light collector and a diffuser positioned inside a target area of a building. In certain embodiments, the tube is configured to direct at least a portion of the daylight transmitted through the light collector towards the diffuser.

Abstract: A window assembly defines a transom opening above a movably deployable reflective shelf that is positionable to reflect sunlight into the building through the transom, and also can be closed over the transom for protection and/or privacy. The reflective shelf may be associated with a mechanically operated a jalousie window. A plurality of shading shelves may be located on the window below the reflecting shelf and similarly operable to open and close.

Abstract: Described herein are optical devices including resonant cavity structures. In one embodiment, an optical fiber includes: (1) an elongated core including an outer surface; (2) an inner reflector disposed adjacent to the outer surface of the core and extending substantially along a length of the core; (3) an outer reflector spaced apart from the inner reflector and extending substantially along the length of the core; and (4) an emission layer disposed between the outer reflector and the inner reflector and extending substantially along the length of the core, the emission layer configured to emit radiation that is guided within the optical fiber.

Abstract: A laminated optical disk, applied for lighting system or solar energy system, includes a plurality of annular lenses, a base and a circular light guiding unit. The annular lenses are arranged in order from center to outside to form a disk-structure. Each annular lens has a light-input curved surface and a light-output curved surface respectively matching the different thickness of the base. The light-input curved surface is opposite to the center. The light-output curved surface is opposite to the light-input curved surface, and facing to the center. The light is incident on the light-input curved surface, refracted and tended to concentrate by the light-input curved surface. Besides, the light exiting from the annular lens is to be refracted to the direction of the center by the light-output curved surface. The base of the laminated optical disk can significantly improve the light leakage problem by different annular lenses.

Abstract: Lighting devices and methods for providing daylight to the interior of a structure are disclosed. Some embodiments disclosed herein provide a daylighting device including a tube having a sidewall with a reflective interior surface, a light collecting structure, and a light reflector positioned to reflect daylight into the light collector. In some embodiments, the light collector is associated with one or more light-turning and/or light reflecting structures configured to increase the amount of light captured by the daylighting device. Optical elements may allow for the absorption and/or selective transmission of infrared light away from an interior of the daylighting device.

Abstract: A sheet-form light-redirecting optical article for illuminating building interiors with sunlight. At least one embodiment comprises a sheet of optically transmissive rigid material, preferably Poly(methyl methacrylate), in which a plurality of deep and narrow parallel channels are formed and arranged in two perpendicular arrays. Each channel has opposing walls configured for reflecting light by means of a Total Internal Reflection (TIR). At least a portion of off-axis rays incident onto the surface of the sheet is redirected by the TIR walls of the light-guiding channels. At least one embodiment comprises a grid formed by intersecting specular reflectors and further comprises a light diffusing element optically coupled to the grid. Disclosed also are a method for making the intersecting arrays of light-redirecting channels.

Abstract: An illumination system for illumining an anechoic chamber includes a light gathering device mounted on an outer surface of the anechoic chamber for gathering daylight, a light guiding post mounted to the anechoic chamber, and a diffusion device received in the anechoic chamber. The light guiding post is connected between the light gathering device and the diffusion device. The light guiding post includes two shields mounted in the light guiding post, which are respectively adjacent to the light gathering device and the diffusion device, to protect the anechoic chamber from electrostatic or magnetic interference.

Abstract: A light guide plate includes a substrate and horizontally oriented elongated prisms. The substrate is positioned on mounted on an outside surface of a window of a building and includes a first surface and an opposing second surface. The second surface faces the outside surface. The substrate is made of transparent material. The prisms are arranged on the first surface and parallel to each other. Each prism includes a flat side surface facing upward and a curved side surface facing downward. The flat side surface and the curved side surface extend from the first surface and intersect at a line away from the first surface. Each curved side surface is configured for reflecting light passing through the flat side surface to a ceiling of the building.

Abstract: A system providing consistent and intense sunlight to light-guiding structures for redirecting sunlight to the interior of a building is presented. One aspect of the inventive subject matter includes an illumination system comprising a solar redirector and at least one optical converter. The solar redirector can be configured to extend outward from a wall of a building and to redirect sunlight to exterior sections of the wall below the solar redirector. The optical converter can be configured to mount on at least one of the exterior sections of the wall and to receive the redirected sunlight and distribute the redirected sunlight to an interior of the building.

Abstract: Some embodiments provide a fenestration apparatus including at least one glazing pane capable of being installed in an opening of a building envelope and a tessellated structure disposed adjacent to the at least one glazing pane. The tessellated structure can include at least one partition having a first face and a second face. The at least one partition can define a plurality of spatially separated cells within a substantially contiguous region of the opening. Each of the plurality of spatially separated cells can have a cell width and a cell depth. Each of the plurality of spatially separated cells can be at least partially surrounded by the first face of the at least one partition, the second face of the at least one partition, or a combination of the first face and the second face of the at least one partition.

Abstract: A light guide plate includes a substrate and horizontally oriented elongated prisms. The substrate is positioned on mounted on an outside surface of a window of a building and includes a first surface and an opposing second surface. The second surface faces the outside surface. The substrate is made of transparent material. The prisms are arranged on the first surface and parallel to each other. Each prism includes a flat side surface facing upward and a curved side surface facing downward. The flat side surface and the curved side surface extend from the first surface and intersect at a line away from the first surface. Each curved side surface is configured for reflecting light passing through the flat side surface to a ceiling of the building.

Abstract: Disclosed is a window blind solar energy management system for capturing solar energy to manage illumination and temperature within a defined space. Blinds comprising curved louvers are hung from the internal frame of a window, each louver having a concave, highly reflecting specular mirrored surface that focuses incoming solar beam radiation onto a thin area on the back of the adjacent louver. The angle of the louvers is adjusted by an integral automatic controller so that the thin strip of light can be focused on one or two of three regions on the back of the adjacent louver which are designed to either reflect, absorb, or reject the incoming light.

Abstract: An optical element includes a first surface, a second surface positioned to face the first surface, and a plurality of reflecting surfaces arrayed in a first region defined by the first surface and the second surface, wherein the reflecting surfaces have a first length in a first direction vertical to the first surface and are arrayed at a pitch in a second direction perpendicular to the first direction, light incident on one of the first surface and the second surface is reflected by the reflecting surfaces toward the other surface, and predetermined parameters satisfy predetermined relational formulae representing conditions for ensuring total reflection at the reflecting surfaces and for avoiding total reflection at a light emergent surface.

Abstract: An optical distributor (10) is formed as a reflector with one or more sloping surfaces. The sloping surfaces have varying angles of inclination from a bottom edge (20) to a top edge of the reflector. The sloping surfaces may form a substantially pyramidal or conical frustum-shaped surface. The sloping surfaces may additionally or alternatively form a band of adjacent or contiguous faceted surfaces. The reflector is configured to receive light rays through an opening (32) in a first plane (30) and reflect light rays radially outward and upward at varying angles of reflection (8B) to a bottom surface of the first plane (30) in a manner that illuminates both the bottom surface of the first plane (30) and an area (40) below the first plane (30). The reflected light may illuminate the first plane (30) and the area (40) below in a substantially uniform manner.

Abstract: The present invention relates to a solar light condensing system for realization of natural lighting, and more particularly, to a vertical solar light condensing system which is formed on an outer wall of a building using a reflective member and a light condensing member so as to secure large light condensing area and to increase light condensing efficiency.

Abstract: Lighting devices and methods for illuminating the interior of a building with natural daylight are disclosed. In some embodiments, a daylighting apparatus includes a tube having a sidewall with a reflective interior surface, an at least partially transparent light collector with one or more light turning elements, and a light reflector positioned to reflect daylight into the light collector. The one or more light turning elements can turn direct and indirect daylight into the tube so that it is available to illuminate the building. In some embodiments, the tube is disposed between the light collector and a diffuser positioned inside a target area of a building. In certain embodiments, the tube is configured to direct at least a portion of the daylight transmitted through the light collector towards the diffuser.

Abstract: The disclosure generally relates to concentrating daylight collectors, and in particular to concentrating daylight collectors useful for interior lighting of a building. The concentrating daylight collectors generally include a plurality of moveable reflective vanes and a Cassegrain-type concentrator section.

Abstract: A general purpose energy saving light amplification unit suitable as a lantern, guide light, background light, safety light, ornament or decorative object, said unit adapted to harness external surrounding ambient light, or other remote energy sources from at least two directions, employing a plurality of reflector members to receive and concentrate energy in order to luminesce or fluoresce an optimally placed mutually shared luminescent or fluorescent body member, lodged in a tapered or convergent section of a hyperbola or between at least two juxtaposed reflectors, stimulating photon and electron activity resulting in maximum amount of transmitted visible light from at least two directions, irrespective of receptive direction or angle of origin of light source.

Abstract: A lighting device includes a substantially cylindrical tube defining an interior and an exterior, and a longitudinal axis extending between a first end and a second end. The first end of the tube defines a substantially cylindrical opening disposed in a plane at a first angle that is substantially perpendicular to the longitudinal axis, and the second end of the tube defines a substantially elliptical opening disposed in a plane at a second angle that is substantially non-perpendicular to the longitudinal axis. A reflective surface is provided on the interior of the tube, and a substantially cylindrical flashing is provided about the exterior of the tube. A substantially transparent dome is coupled to the tube proximate the first end, and a diffuser is coupled to the tube proximate the second end.

Abstract: An indirect daylighting device for a building with an interior space may include a suspension system configured for securing to a building structure and a pan secured to the suspension system and having an incident surface and a cross-sectional profile forming a plurality of waves, wherein the incident surface is arranged to receive natural light entering a building and reflect the natural light to provide indirect lighting to the interior space of the building.

Abstract: Generally, the present disclosure provides a light duct bend used in a mirror-lined light duct system. In one aspect, the light duct bend includes an input region having a first propagation direction, an output region having a second propagation direction disposed at a bend angle to the first propagation direction, and a transition region connecting the input region to the output region. The transition region includes a plurality of vanes that subdivide the duct into channels, which can reduce the loss and/or disruption of collimation about one or more bends in the light duct system.

Abstract: A low-cost sunlight redirecting element including multiple substantially identical redirecting structures uniformly arranged and fixedly disposed on a base, where each redirecting structure includes multiple optical surface regions that are cooperatively formed and arranged such that, when the sunlight redirecting element is operably fixedly oriented relative to a stationary target with sunlight directed along an incident direction onto the redirecting structures, at least some of the sunlight is transmitted between the corresponding optical surface regions of each redirecting structure, and redirected from the corresponding optical surface regions toward the target's surface. The optical surface regions are shaped and arranged to redirect the sunlight toward the fixed target surface even when the sunlight's incident angle direction changes during the course of a year. A stationary sunlight redirecting system (e.g.

Abstract: A low numerical aperture (low-NA) light concentration and transmission system collects, concentrates and transmits light for interior illumination. A solar tracker aligns a primary light concentrator to collect light and direct the light to a secondary light concentrator and a filter for removing ultraviolet and infrared radiation. On exiting the secondary light concentrator, the optical axis of the concentrated light is aligned to optimize the numerical aperture of the concentrated light with a numerical aperture (NA) optimizer having a light guide to direct the concentrated light to an interior luminaire. The method of the low numerical aperture transmission of light has the advantages of fewer reflections in the light guide, low loss, low cost, and easy installation and operation.