3032results about "Photometry using reference value" patented technology

A wireless lighting control system comprises a daylight sensor for measuring a light intensity in a space and a dimmer switch for controlling the amount of power delivered to a lighting load in response to the daylight sensor. For example, the daylight sensor may be able to transmit radio-frequency (RF) signals to the dimmer switch. The system provides methods of calibrating the daylight sensor that allow for automatically measuring and / or calculating one or more operational characteristics of the daylight sensor. One method of calibrating the daylight sensor comprises a “single-button-press” calibration procedure during which a user is only required to actuate a calibration button of the daylight sensor once. In addition, the daylight sensor is operable to automatically measure the total light intensity in the space at night to determine the light intensity of only the electrical light generated by the lighting load.

The invention concerns a method and a circuit for maximum power point tracking of a variable power source from a comparison of an image of the power (P) supplied by the power source, the circuit comprising two elements (14, 31) providing different propagating delays to a physical quantity proportional to the power image, a comparator (16) of the outputs of the delaying elements to control a trigger (17) supplying a signal (Q) with two automatic control states to a static power converter, and means (33) for detecting a transitory operating condition from variations in oscillations of an established operating condition and means (32) for modifying the delay input by the slower delaying element (31).

A method in a computerized system including an image sensor mounted in a moving vehicle. The image sensor captures image frames consecutively in real time. In one of the image flames, a spot is detected of measurable brightness; the spot is matched in subsequent image frames. The image frames are available for sharing between the computerized system and another vehicle control system. The spot and the corresponding spot are images of the same object. The object is typically one or more of headlights from an oncoming vehicle, taillights of a leading vehicle, streetlights, street signs and / or traffic signs. Data is acquired from the spot and from the corresponding spot. By processing the data, the object (or spot) is classified. producing an object classification. The vehicle control system controls preferably headlights of the moving vehicle based on the object classification. The other vehicle control system using the image frames is one or more of: lane departure warning system, collision warning system and / or ego-motion estimation system.

A new way of mixing instrumental and digital means is described for the general field of wave front sensing. The present invention describes the use, the definition and the utility of digital operators, called digital wave front operators (DWFO) or digital lenses (DL), specifically designed for the digital processing of wave fronts defined in amplitude and phase. DWFO are of particular interest for correcting undesired wave front deformations induced by instrumental defects or experimental errors. DWFO may be defined using a mathematical model, e.g. a polynomial function, which involves coefficients. The present invention describes automated and semi-automated procedures for calibrating or adjusting the values of these coefficients. These procedures are based on the fitting of mathematical models on reference data extracted from specific regions of a wave front called reference areas, which are characterized by the fact that specimen contributions are a priori known in reference areas. For example, reference areas can be defined in regions where flat surfaces of a specimen produce a constant phase function. The present invention describes also how DWFO can be defined by extracting reference data along one-dimensional (1D) profiles. DWFO can also be defined in order to obtain a flattened representation of non-flat area of a specimen. Several DWFO or DL can be combined, possibly in addition with procedures for calculating numerically the propagation of wave fronts. A DWFO may also be defined experimentally, e.g. by calibration procedures using reference specimens. A method for generating a DWFO by filtering in the Fourier plane is also described. All wave front sensing techniques may benefit from the present invention. The case of a wave front sensor based on digital holography, e.g. a digital holographic microscope (DHM), is described in more details. The use of DWFO improves the performance, in particular speed and precision, and the ease of use of instruments for wave front sensing. The use of DWFO results in instrumental simplifications, costs reductions, and enlarged the field of applications. The present invention defines a new technique for imaging and metrology with a large field of applications in material and life sciences, for research and industrial applications.

Apparatuses and methods include a solar array having one or more strings of series-connected local management units (LMUs). Each LMU is parallel-connected to one of a plurality of solar modules. The strings are connected in parallel via a parallel bus. Local string management units (LSMUs) can increase or decrease an output voltage of the solar array by upconverting or downconverting string output voltages from each string. LSMUs can also operate in a bypass mode to increase overall power output.

A light output control system for implementing a method for sensing the tri-stimulus values for controlling a light output illuminated from an LED based luminary is disclosed. The system comprises one or more filter / photo diode sensors for sensing a first set of tri-stimulus values of the light output and providing signals indicative thereof. The signals are utilized in a transformation matrix whereby a second set of tri-stimulus values is obtained. The system controls the light output as a function of the second set of tri-stimulus values.