Abstract:
Computer-implemented methods of simulating optical systems such as backlights, and machine-readable media for carrying out such methods, are disclosed. The optical systems include optical elements. In some cases, different first and second probability functions can be acquired for first and second elements (respectively) of the optical system. A combined probability function can then be calculated using at least the first and second probability functions, and rays can be traced through the optical system using the combined probability function. The first, second, and combined probability functions can be bi-directional scattering distribution functions (BSDFs), having values stored in cells wherein each cell corresponds to a particular entrance and exiting direction. Some methods can include acquiring a first probability function associated with a first element, the first probability function including cell values as a function of incident direction and exiting direction. Rays can be traced through the optical system using the first probability function.
Abstract:
A hollow light-recycling backlight has a "semi-specular" component providing a balance of specularly and diffusely reflected light improving the uniformity of the light output. The component may be arranged on the reflectors (1021), (1014) or inside the cavity (1016). This balance is achieved by designing the component's "transport ratio" defined by (F - B) / (F + B), (F and B are the amounts of incident light scattered forwards and backwards respectively by the component in the plane of the cavity) to lie in a certain range. Furthermore, the product of the front and back reflector "hemispherical" reflectivities should also lie in a given range. Alternatively, the "cavity transport value", a measure of how well the cavity can spread injected light from the injection point to distant points in the cavity should lie in a further range and the "hemispherical" reflectivity of the back reflector should be >0.7.
Abstract:
The disclosure generally relates to highly efficient light duct light splitters that are capable of splitting the light propagating within a light duct into two different ducts, with nearly 100 percent efficiency. In particular, the described light splitters are configured in a "Tee" shape with a reflective splitter element.
Abstract:
A light directing substrate includes a back major surface and a front major surface opposing the back surface. The back major surface includes light reflection regions and light transmission regions. The front surface includes a plurality of lenticular lens elements. A graphic image disposed on or in the light directing substrate.
Abstract:
A light directing composite film includes a planar top major surface, a planar bottom major surface, a plurality of lenticular lens elements disposed between the top major surface and the bottom major surface, and a plurality of light reflection regions and light transmission regions disposed between the plurality of lenticular lens and the planar bottom major surface.
Abstract:
The present disclosure relates to illumination or lighting assemblies and systems that provide illumination using LEDs. In one aspect, the present disclosure provides a lighting assembly, comprising: multiple light emitting diodes that emit light; an optical system that directs the light emitted by the light emitting diodes, the optical system positioned adjacent to light emitting diodes; and a cooling fin including a two-phase cooling system, the cooling fin positioned adjacent to the light emitting diodes such that the two-phase cooling system removes heat from the light emitting diodes. In another aspect, the present disclosure provides a lighting system including multiple lighting assemblies. The lighting assemblies and systems of the present disclosure can be used in, for example, a street light, a backlight (including, for example, a sun-coupled backlight), a wall wash light, a billboard light, a parking ramp light, a high bay light, a parking lot light, a signage lit sign (also referred to as an electric sign), static signage (including, for example, sun-coupled static signage), illuminated signage, and other lighting applications.
Abstract:
Illumination devices having a partially transmissive front reflector, a back reflector, and a cavity between them are disclosed. At least one light injector including a baffle and a light source is disposed in the cavity. The light injector is capable of injecting partially collimated light into the cavity. The output area of the illumination device can be increased by disposing light injectors progressively within the cavity, without sacrificing uniformity of the light emitted through the output area.
Abstract:
A backlight unit (10) has a hollow cavity (16) instead of employing a light guide. One or more light sources (24a-c), such as LEDs, are arranged to emit light into the cavity, which is formed by a front (12) and a back reflector (14). The backlight is typically of the edge-lit type. The backlight can have a large area, is thin and consists of fewer components than conventional devices. Its design permits light recycling. The unit emits light of a predefined polarisation and can be arranged to have desired horizontal / vertical viewing angle properties. Light is uniformly distributed within the guide and the light output (20b, 2Od) is substantially collimated. Such backlights occupy a specific region in a parameter space defined by two parameters: first, the ratio of the output emission area to the total source emission area should lie in the range 0.0001 to 0.1; and second, the ratio of the SEP to the height of the cavity (H) should be in the range 3 to 10, where the SEP is an average plan view source separation, a special measure of the average spacing of light sources in the plane of the unit. There is also a discussion on the required number of light sources N, their arrangement near the periphery of the cavity, as well as the shape and size of the output emission area. A required minimum brightness uniformity (VESA) value to be maintained, when a subset of Madjacent sources is switched off (where M is at least 0.1 N or M> 2 or both), is also disclosed. The backlight can be used for a display or for general lighting purposes.
Abstract:
The present disclosure describes light delivery and distribution components of a light duct that can be used as a luminaire, such as a bollard-style luminaire that can be useful for the illumination of pedestrian crosswalks, the light engine useful in the luminaire, and methods for making the light engine and the luminaire. The present disclosure further describes methods for crosswalk illumination using the bollard-style luminaires, and methods of communication between bollard luminaires. The bollard luminaire includes a design that generally confines light to illuminate the crosswalk and the pedestrian in the crosswalk, such that light that could produce glare for the pedestrian and/or a driver approaching the crosswalk is minimized.
Abstract:
The disclosure generally relates to highly efficient light duct light extractors that are capable of extracting a portion of the light propagating within a light duct with nearly 100 percent efficiency. In particular, the described light extractors are configured in a "Tee" shape with a reflective diverter element.