Method of manufacturing a spectrally selective surface. The method comprises cleaning an outside of a tubular substrate, e.g. by sonicating in acetone, polishing the cleaned outside, and depositing a CoCr coating on the polished outside, i.e. the tubular substrate's outside. The CoCr coating comprises Co(II) compounds and Cr(III) compounds but no Cr(VI) compounds. By applying a DES electrolyte Cr(III)-ions may be solved in the electrolyte such that a receiver tube arranged in the electrolyte may become coated with a selective CoCr coating from Cr(III)-ions, where the optical characteristics regarding absorptance and emittance for the resulting receiver tube are comparable or surpasses traditional black chrome. Thereby use of harmful hexavalent chrome could be avoided, which may achieve more healthy and environmental friendly conditions. Particularly, no harmful Cr(VI)-ions or rest substances comprising them will contaminate ambient air or need to be handled or disposed.

Systems for generating solar power are provided. One such system includes a solar radiation collector and one or more side-emitting fiber-optic cables, coupled to the solar radiation collector. The system further includes one or more photovoltaic cell enclosures, including an outer housing and one or more photovoltaic cells, wherein the one or more side-emitting fiber-optic cables is positioned within the outer housing and configured to emit, to the one or more photovoltaic cells, solar radiation collected from the solar radiation collector.

A tubular LED light fixture includes a lamp holder; printed circuit board; a plurality of point light sources; lens; strip-shaped convex lens array, located between the lens and printed circuit board and arranged along the length direction of the tubular LED light fixture for converting each point light source into a plurality of consecutive sub point light sources, and the sub point light source converted by the adjacent point light source is connected or overlapped. The invention adopts a strip-shaped convex lens array which forms a line light source only by diffusing light from the point light source only in the length direction of the strip light fixture, preventing light from diffusing in multiple directions, so that the line source is purified. The lens is arranged to perform light distribution in the other direction to the line source, thereby reducing energy attenuation and ensuring the light effect.

A light-collecting unit having an inverted pyramid shape is described. The light-collecting unit has one or more outer light-collecting panel facing inward. The light-collecting unit also includes a first plurality of inner, light-collecting panels facing outward and a second plurality of inner, light-collecting panels facing inward. A flower base is configured to support the first plurality of inner, light-collecting panels and the second plurality of inner, light-collecting panels. The first plurality of inner, light-collecting panels is disposed on an outer facing side of the flower base and the second plurality of inner, light-collecting panels is disposed on an inner facing side of the flower base. The light-collecting unit may also include a light emitting element, such as an LED or fiber optic cable end. The light emitting element may provide infrared light to the light-collecting unit. The light emitting element may provide the light using pulse-wave modulation.

The collimator comprises an output area approximately having the shape of an n-gon with legs and apices, for collimation of light rays emitted by a light source. In viewing the collimator from the side from the optical source in the direction of the lighting axis, the collimator comprises n first parts and n second parts. Each first part is associated with one of the legs of the n-gon and comprises the first sector of the first circular collimator, approximately inscribed in the n-gon so that this leg is tangential to the outline of the circular output area of the first circular collimator. Each second part is associated with one of the apices and is comprised in a second sector of the second circular collimator, approximately circumscribed around the n-gon so that the outline of the output area of this second circular collimator passes through the apex.

This invention discloses a low-cost backlight module including a plurality of light source assemblies arranged in an array, and a reflector as well as a diffuser plate both disposed beside each light source assembly, wherein the reflector includes a circle of side reflection wall arranged annularly around the light source assembly, each of the light source assemblies includes a plurality of spot light sources spaced apart circumferentially and faced toward the side reflection wall, and the light emitted by the spot light source toward the side reflection wall is reflected by the side reflection wall and then emitted out from the diffuser plate. This invention further discloses a display device. An area of the diffuser plate that is emitted by each spot light source is enlarged and the emitted light becomes more uniform. The number of spot light sources is reduced and the problem of LED Mura is avoided.

Embodiments described herein may relate to a system comprising a plurality of optical elements, comprising at least a first optical element and one or more secondary optical elements, a heliostat comprising the first optical element, where the heliostat is operable to move the first optical element to continuously reflect light from a non-stationary light source in a beam towards a first of the secondary optical elements, and where the secondary optical elements are arranged to re-direct the reflected beam of light towards an illumination target. The system further includes a controller configured to receive position data indicative of the position of the non-stationary light source over time, and in response to the position data, control at least the heliostat to continuously direct the beam of light towards the first of the secondary optical elements, such that the beam of light is continuously re-directed towards the illumination target.

A first light guide guides first light in a first light guiding path. The first light is of light irradiated from the light source to a sheet. A first detection unit receives reflected light from the sheet and outputs an image signal indicating an image of a surface of the sheet. A second light guide guides second light in a second light guiding path different from the first light guiding path. The second light is of the light irradiated from the light source and is different from the first light. A second detection unit receives the second light and output a detection signal corresponding to a light amount of the second light. A control unit controls a light emission amount of the light source based on the detection signal.

Examples of the present disclosure disclose an optical element, a light source module using the optical element and a lighting device using the light source module. The optical element includes: a light distribution portion configured to receive irradiated light emitted from a light-emitting unit and allow the irradiated light to be emitted upon distribution, where the light emitted from the light distribution portion upon distribution has an irradiation range; and a light-shielding portion provided integrally with the light distribution portion, where the light-shielding portion is engaged with the light distribution portion to form a light-shielding receiving chamber, and the light-shielding receiving chamber is located outside the irradiation range.

The present invention is in the field of solar energy collectors. In particular, the invention is directed to solar energy collectors that operate by concentrating solar radiation onto an absorber using a reflector. The invention may be embodied in the form of a unitary planar solar radiation reflector array having a plurality of upwardly facing reflective surfaces each of which is configured to reflect incident solar radiation, wherein each upwardly facing reflective surface is formed by coating a substrate with a coating material. The coating material may be a metallic coating of substantially even thickness formed by a metal deposition method such as a vapour deposition method or a thermal spray method.