摘要:
Proposed is a light sensor (1), comprising at least one wavelength selective photo-detector (10), a lens (20) and an aperture (30).The wavelength selective photo-detector allows detecting light within a predefined wavelength range falling on the sensor. The lens project light on the photo-detector and the aperture defines a field of view of the light sensor. The photo-detector (10), the lens (20), and the aperture (30) are arranged in a telecentric configuration. Advantageously, this allows light to impinge on the wavelength selective photo-detector within a predefined range of angles irrespective of the direction of the light incident on the aperture, thus removing the angle dependent response of the wavelength selective photo-detector.
摘要:
A light-emitting diode has a first electrode, a second electrode and a light-emitting layer. A receptor layer of an ion receptor has an affinity for ions of a first charge and is positioned between the first electrode and the light-emitting layer. A further layer includes immobile ions of a second charge and is positioned between the second electrode and light-emitting layer. The immobile ions initially have attached counterions of the first charge that move towards the receptor layer upon application of an electric field for capture by the receptor layer. Upon capture of the counterions, a concentration of immobilized ions of the first charge is formed at the first electrode yielding an ion gradient for injection of electrons and holes resulting in emission of light.
摘要:
The present invention relates to a method for illuminating a scene having an average lighting setting, the method comprising the steps of receive scene information from an image sensor (110) comprising a plurality of pixels, determine chromaticity coordinates for the scene based on the scene information, and determine, based on the chromaticity coordinates, control values used for driving the at least two differently colored light sources (L1, L2, L3), thereby allowing for illumination of the scene without essentially changing the average lighting setting of the scene. The present invention provides for the possibility to in a more precise way match the average lighting setting of the scene, wherein it is possible to produced light that assure a more natural rendering of illuminated objects in the scene. In comparison to the prior art, for light sources which have spectra far from the black body curve, the chromaticity coordinates are a better representation of the color of ambient light illuminating the scene than when using the correlated color temperature. The present invention also relates to a corresponding illumination device (100).
摘要:
This invention relates to a control system for controlling the light output of a LED luminaire comprising a single color LED group consisting of at least one LED. The control system comprises a spectral filter and a photodetector, which thus receives spectrally filtered light from the LED group. The photodetector generates a response signal which is applied to a control device. The control device controls the light output of said LED group at least partially on the basis of the response signal. The control system further includes an incidence angle limiting device arranged to limit the angle of incidence of the LED light received by said filter.
摘要:
The present invention relates to a control system (13) and method for controlling the light output of an emitting unit (11) having at least one LED (15) and emitting light of at least one colour. The control system (13) comprises a feedback based on a detection unit (19) detecting the light output of the emitting unit (11), a detection pulse generator (27), a suppression unit (23) suppressing environmental light interferences in detected light, and a control unit (21) for controlling the light output of the emitting unit on basis of a comparison between a reference signal representing a desired light output of the emitting unit and an output signal of the suppression unit. The detection pulse generator (27) generates detection pulses a-periodically. Thus, an a-periodicity is introduced into the feedback processing of the light output. This provides a possibility by means of conventional suppression algorithms to eliminate or reduce interfering environmental light, particularly pulsed light.
摘要:
A temperature indicator (1) for indicating a high temperature at a surface (13) comprises a light-emitting electro-chemical cell (4) having a first electrode (8), a second electrode (9) and a light-emitting layer (10) being sandwiched between the two electrodes (8, 9). The light-emitting layer (10) comprises a matrix and ions being movable in the matrix, the mobility of said ions in said matrix being temperature dependent. A power source (5) is adapted for driving the light-emitting cell (4) with an AC voltage. The frequency of the AC voltage is tuned in such a way that, above a certain temperature level, the ions move fast enough in the matrix to provide a sufficient charge gradient in the light-emitting electrochemical cell (4) for the light-emitting electrochemical cell (4) to emit light before the AC power source (5) shifts the polarity of the voltage.
摘要:
The present invention relates to a method for controlling an illumination device (100), the illumination device (100) comprising a flux sensing unit (101) and at least two differently colored light sources (102, 103, 104), the method comprising the steps of switching on and off each of the light sources according to a predefined pattern, acquiring measurement values by means of the flux sensing unit at predetermined intervals in accordance with the predefined pattern, calculating a color point for each of the light sources based on the measurement values, calculating a difference between the color points and corresponding reference color points, and adjusting an analog current drive level of the light sources, wherein the difference is minimized such that a desired color is obtained. The present invention provides for the possibilities to in a more accurate way correct for the color changes due to change in drive current, temperature, and aging effects. Furthermore, the control method according to the present invention does not require a factory calibration, or knowledge of batch specific binning information, for obtaining the current or temperature related characteristics of the light sources, which significantly reduces the cost normally related to factory calibration and batch specific binning information. Furthermore, the present invention relates to an illumination device (100) comprising means for performing such a method.