Abstract: A lighting device comprising a light source being configured to generate source light of a white light emission spectrum having a color correlated temperature (CCT) in a range of 2500-20000K and comprising a control unit being configured to control a lighting element for tuning of the source light with respect to a ratio between a first emission peak in a wavelength range of 460-490 nm and a second emission peak in a wavelength range of 430-460 nm. Thus a lighting device with a tunable/adjustable spectrum is provided that can switch between a first operation state of energy efficiency lighting with a blue peak in the second wavelength range of 430-460 nm, but with blue hazard risk, and a second operation state of less efficient but safe, healthy lighting with a biological stimulant having a blue peak in the first wavelength range of 460-490 nm.

Abstract: A method comprises determining (203) whether a person has been and/or will be irradiated with an amount of UV radiation exceeding a threshold and controlling (205), in dependence on the determination, one or more light sources to render light comprising a light component having wavelengths in the range 550 to 900 nm. A spectral power distribution of the light is chosen such that the light has a cytochrome C oxidase efficacy complying with the following conditions: for DNA synthesis: the cytochrome C oxidase efficacy is at least 6.2*v?-2.48 mW/lm if the light’s v? is lower than 0.539 or at least 0.85 mW/lm if the light’s v? is equal to or higher than 0.539; for RNA synthesis: the cytochrome C oxidase efficacy is at least 7.5*v?-2.975 mW/lm if the light’s v? is lower than 0.539 or at least 1.05 mW/lm if the light’s v? is equal to or higher than 0.539.

Abstract: A camera-based sensor device (200) and method for use in a controllable lighting system (100). The camera-based sensor device (200) comprises: a communications interface (203); a camera (201) for capturing images of a scene, each image comprising an array of pixels; and a processor (202). The processor (202) is configured to determine at least one light performance indicator, LPI, from an image captured by the camera (201). The LPI is a combined metric derived from a plurality of pixels of the array of pixels in the image. The processor (202) is configured to transmit, via the communications interface (203), the determined at least one LPI to the controllable lighting system (100) for use by the controllable lighting system (100) to make a control decision based on the LPI. The processor (202) does not transmit any of the images of the scene.

Abstract: A method and computer device for determining a spatial luminance distribution over at least one image of a scene illuminated by at least one illuminant (121) are provided. The image comprises RGB channels. A linear combination of the RGB channels is applied to determine the luminance distribution. The linear combination has a set of coefficients comprising a respective coefficient for each of the RGB channels. The coefficients are determined by identifying a spectral power distribution, SPD, of the at least one illuminant and performing a search to determine values of the set of coefficients that minimise a spectral mismatch between: a) the identified SPD weighted by the linear combination; and b) the identified SPD weighted by a luminosity function.

Abstract: A lighting device comprising a light source being configured to generate source light of a white light emission spectrum having a color correlated temperature (CCT) in a range of 2500-20000K and comprising a control unit being configured to control a lighting element for tuning of the source light with respect to a ratio between a first emission peak in a wavelength range of 460-490 nm and a second emission peak in a wavelength range of 430-460 nm. Thus a lighting device with a tunable/adjustable spectrum is provided that can switch between a first operation state of energy efficiency lighting with a blue peak in the second wavelength range of 430-460 nm, but with blue hazard risk, and a second operation state of less efficient but safe, healthy lighting with a biological stimulant having a blue peak in the first wavelength range of 460-490 nm.

Abstract: An illumination device (100) for illuminating an at least partially reflective surface (S) viewable by an observer (O) is disclosed. The illumination device (100) comprises a light-emitting module (110, 120) adapted to generate polarized light having a selected direction of polarization. Further, the illumination device (100) is adapted to illuminate the at least partially reflective surface (S) with the polarized light, and is adjustable so as to effect adjustment in the direction of polarization of light illuminating the at least partially reflective surface (S) in relation to the orientation of a plane of incidence of light incident on the at least partially reflective surface. An indicator (130) is arranged such as to provide guidance for the observer (O) how to adjust the direction of polarization of light illuminating the at least partially reflective surface (S). Thereby, the extent of light reflection from the at least partially reflective surface (S) may be adjusted.

Abstract: The invention relates to an illumination system comprising a luminaire which is configured to provide light according to a plurality of preset combinations of illumination level and color temperature, controlled via a control protocol. The system further comprises a user interface comprising means to (manually) select the illumination level and color temperature from said plurality of preset combinations. The number of preset combinations is at least three. The control protocol comprises transition times for transitions between said preset combinations, said transition times being in the range of about 2 seconds to about 5 minutes. The invention further relates to an illumination method using the illumination system and to a controller uploaded with said preset lighting settings. The use of the system in dependence on the activity, time of day or atmosphere in the classroom has been proven to improve the learning behavior of children. It therefore is a learning tool for teachers.

Abstract: A lighting device comprising a first light source issuing a first beam and a second light source issuing a second beam. Said first and said second light source are dimmable and together issue light with a total light flux. At a mutually equal light flux of the first and the second beam, the glare level of the second beam is lower than the glare level of the first beam. The lighting device further comprises at least one (programmed) controller which, during operation, moderates said dim levels such that in at least a range of the illumination level a ratio of the dim level of the second beam to the dim level of the first beam increases in a gradual manner with increasing total light flux.

Abstract: An illumination device (100) for illuminating an at least partially reflective surface (S) viewable by an observer (O) is disclosed. The illumination device (100) comprises a light-emitting module (110, 120) adapted to generate polarized light having a selected direction of polarization. Further, the illumination device (100) is adapted to illuminate the at least partially reflective surface (S) with to effect the polarized light, and is adjustable so as adjustment in the direction of polarization of light illuminating the at least partially reflective surface (S) in relation to the orientation of a plane of incidence of light incident on the at least partially reflective surface. An indicator (130) is arranged such as to provide guidance for the observer (O) how to adjust the direction of polarization of light illuminating the at least partially reflective surface (S). Thereby, the extent of light reflection from the at least partially reflective surface (S) may be adjusted.

Abstract: The invention relates to an illumination system comprising a luminaire which is configured to provide light according to a plurality of preset combinations of illumination level and color temperature, controlled via a control protocol. The system further comprises a user interface comprising means to (manually) select the illumination level and color temperature from said plurality of preset combinations. The number of preset combinations is at least three. The control protocol comprises transition times for transitions between said preset combinations, said transition times being in the range of about 2 seconds to about 5 minutes. The invention further relates to an illumination method using the illumination system and to a controller uploaded with said preset lighting settings. The use of the system in dependence on the activity, time of day or atmosphere in the classroom has been proven to improve the learning behavior of children. It therefore is a learning tool for teachers.

Abstract: The invention relates to an illumination system comprising a luminaire which is configured to provide light according to a plurality of preset combinations of illumination level and color temperature, controlled via a control protocol. The system further comprises a user interface comprising means to (manually) select the illumination level and color temperature from said plurality of preset combinations. The number of preset combinations is at least three. The control protocol comprises transition times for transitions between said preset combinations, said transition times being in the range of about 2 seconds to about 5 minutes. The invention further relates to an illumination method using the illumination system and to a controller uploaded with said preset lighting settings. The use of the system in dependence on the activity, time of day or atmosphere in the classroom has been proven to improve the learning behavior of children. It therefore is a learning tool for teachers.

Abstract: The present invention refers to a luminaire comprising a plurality of directed light sources arranged in a surface of a three-dimensional body and a controller for controlling the operational state of the luminaire. The controller comprises a three-dimensional touch-sensitive surface. Each point on the touch-sensitive surface is allocated to a position of the body surface such that an operational state of at least one light source at a position of the body surface is changeable by touching a point on the touch-sensitive surface allocated to this position. A corresponding method for controlling a luminaire comprises the steps of detecting a touch at a point on a three-dimensional touch-sensitive surface and changing an operational state of at least one light source at a position of the body surface allocated to the touch point on the touch-sensitive surface.

Abstract: A lighting device comprising a first light source issuing a first beam and a second light source issuing a second beam. Said first and said second light source are dimmable and together issue light with a total light flux. At a mutually equal light flux of the first and the second beam, the glare level of the second beam is lower than the glare level of the first beam. The lighting device further comprises at least one (programmed) controller which, during operation, moderates said dim levels such that in at least a range of the illumination level a ratio of the dim level of the second beam to the dim level of the first beam increases in a gradual manner with increasing total light flux.

Abstract: An optical system (100) is provided, having at least one light emitting module (110) adapted to emit light, and at least one reflector (120) arranged relatively to a corresponding one of the at least one light emitting module (110) so as to receive at least some light emitted by the at least one light emitting module (110). A polarizer (130) is provided so as to transmit light having at least a first polarization direction and to reflect light having at least a second polarization direction. The light emitting module (110) comprises at least one light emitting surface portion (114) and at least one corresponding reflective surface portion (112) which are arranged point symmetrically to each other with respect to a point (116) coinciding with an optical axis (A) of the at least one reflector (120) such that at least some of the light reflected by the polarizer (130) impinges on the reflective surface portion (112).

Abstract: The invention relates to an illumination system comprising a luminaire which is configured to provide light according to a plurality of preset combinations of illumination level and color temperature, controlled via a control protocol. The system further comprises a user interface comprising means to (manually) select the illumination level and color temperature from said plurality of preset combinations. The number of preset combinations is at least three. The control protocol comprises transition times for transitions between said preset combinations, said transition times being in the range of about 2 seconds to about 5 minutes. The invention further relates to an illumination method using the illumination system and to a controller uploaded with said preset lighting settings. The use of the system in dependence on the activity, time of day or atmosphere in the classroom has been proven to improve the learning behavior of children. It therefore is a learning tool for teachers.

Abstract: The present invention refers to a luminaire comprising a plurality of directed light sources arranged in a surface of a three-dimensional body and a controller for controlling the operational state of the luminaire. The controller comprises a three-dimensional touch-sensitive surface. Each point on the touch-sensitive surface is allocated to a position of the body surface such that an operational state of at least one light source at a position of the body surface is changeable by touching a point on the touch-sensitive surface allocated to this position. A corresponding method for controlling a luminaire comprises the steps of detecting a touch at a point on a three-dimensional touch-sensitive surface and changing an operational state of at least one light source at a position of the body surface allocated to the touch point on the touch-sensitive surface.

Abstract: A display device comprising at least one substrate(1, 2), a first and a second electrode(7, 8), a display medium (12) and an optically active layer(3, 5), wherein said optically active layer comprises a polarizer (3) and is arranged between said substrate and said display medium, and wherein said substrate is made of a birefringent material.

Abstract: A mirror device (1) which can be simultaneously used for display purposes, based on e.g. an LCD display (5) with a polarizing mirror (2) placed in front of it. When the surface area occupied by the display is smaller than the surface area of the mirror, the smaller display can be easily recognized at the front of the mirror. This is masked by introducing absorbing polarizers (30, 40).

Abstract: A mirror device (1) which can be simultaneously used for display purposes, based on e.g. an LCD display (5) with a polarizing mirror (2) placed in front of it. When the surface area occupied by the display is smaller than the surface area of the mirror, the smaller display can be easily recognized at the front of the mirror. This is masked by introducing absorbing polarizers (30, 40).

Abstract: A method for the manufacture of a birefringent layer with tilted optical axis, comprising providing a liquid crystal mixture comprising liquid crystal molecules and a volatile surfactant, aligning said liquid crystal mixture, and evaporate at least part of said volatile compound from the mixture to alter the tilt of the optical axis of said liquid crystal mixture.