摘要:
The invention relates to a high-pressure discharge lamp having a light-transmitting discharge vessel, which includes at least one sealed end and a starting aid, the starting aid being arranged on the at least one sealed end and being designed to be opaque.
摘要:
The invention relates to a circuit arrangement for operating high pressure discharge lamps and corresponding operating method, whereby the input voltage for the pulsed trigger device is increased by means of a series resonance loop (L3, C4), of a cascade circuit, or a symmetrical voltage doubling circuit.
摘要:
The invention relates to a high-pressure discharge lamp having electrodes arranged inside a discharge vessel which define a discharge path of a gas discharge in the discharge vessel, and having a starting device, arranged inside the lamp base for the high-pressure discharge lamp and designed as a pulse starting device, for starting the gas discharge in the discharge vessel, and having, arranged outside its discharge vessel, an auxiliary starting electrode coupled to the pulse starting device, the voltage input of pulse starting device being connected in parallel with the discharge path of the high-pressure discharge lamp, such that according to the invention the voltage across the discharge path serves as supply voltage for the pulse starting device. Also disclosed is an operating method for such a high-pressure discharge lamp.
摘要:
A method of Light-based Communication (LCom) using camera frame-rate based light modulation is provided. The method includes receiving light having modulated light properties that vary at a first frequency from a LCom-enabled luminaire by an image capture device using a global shutter image capture process, comparing light properties received at the image capture device over sequential image capture instances, and determining, from the compared light properties, data encoded by the modulated light.
摘要:
A controller dynamically identifies a switching frequency based power converter output load condition, input voltage, and/or temperature. The controller updates the operating switching frequency to the identified target switching frequency when the identified switching frequency is sufficiently different than a current operating switching frequency of the power converter. In this respect, switching frequency may be dynamically controlled to strike a balance between avoiding saturation of inductive elements and efficient operation of a power converter. A controller may also dynamically control switching frequency by having a thermo resistor incorporated into circuitry that determines switching frequency such that an increase in temperature beyond the threshold temperature directly causes a decrease in switching frequency.
摘要:
Techniques are disclosed for measuring an amount of flicker produced by a light source. In one embodiment, a flicker measuring device includes a photo sensor to measure the amount of light produced by the light source, a dedicated processor to receive and process data from the photo sensor, a memory bus coupled to an analog-to-digital converter (ADC) and to a first memory, and a direct memory access (DMA) bus coupled to the ADC and to a second memory. In another embodiment, a flicker measuring system uses a light sensor, an associated circuit and a portable computing device (PCD), such as a smart phone, to measure an amount of flicker produced by a light source by sending an electrical signal from the light source and associated circuit via an audio output to an audio sub-system of the PCD, so that the PCD may calculate the flicker value.
摘要:
Techniques for supplying auxiliary power to lighting driver circuitry are disclosed. An auxiliary power supply can be used, for example, to provide auxiliary power to a current source that drives an LED string. In some embodiments, the LED string is effectively used as a series resistor to charge a capacitor that provides the auxiliary voltage Vaux. As soon as the capacitor is charged to a given threshold, the LED string can be disconnected from the capacitor and the current through the LED string bypasses the auxiliary supply circuit. Thus, the current source provides a current through the LED string, which in turn may be selectively fed to the auxiliary power supply to provide auxiliary power back to the current source or to provide auxiliary power to other circuitry.
摘要:
Techniques are provided for bi-directional communication between a power supply and one or more light engines (and/or other lighting system components) via the existing power lines so that no additional communication wires are needed. In particular, the power supply can transmit information by modulating its output (voltage or current) and the light engine (or other lighting componentry, such as a sensor) can communicate back by modulating how much power it draws from the power supply. Any suitable type of modulation scheme can be used, and a master-slave arrangement can be used to control the bi-directional communication if so desired, so as to avoid multiple devices communicating over the power line communication channel at the same time. Other embodiments allow a multiple simultaneous communications over the power line communication channel.
摘要:
Techniques are disclosed for detecting stationary presence using IR sensor array. A number of IR images may be captured. Of the IR images captured by the IR sensor array certain pixels can be identified as causing false triggers. These pixels can be identified and filtered to be ignored. The non-filtered pixels of IR images may be averaged over various time intervals to calculate a number of average IR frames. The difference between these average IR frames provides a delta frame. A mask frame may be calculated as the summation of delta frames over time, and the value of the mask frame may be used to detect a stationary human presence even when no delta value is calculated. Alternatively, the mask frame may be used to calculate a background frame that represents the IR signature of stationary or cyclical objects within the scanned area that are not intended to trigger the presence detection system. A stationary presence may be determined by subtracting the background frame from a current average IR frame.
摘要:
Multiple panel luminaires for light-based communication (LCom) and related techniques of use are disclosed. Each luminaire panel may comprise at least one solid-state light source, where the light sources are configured to output light. The luminaire may also include at least one modulator configured to modulate the light output of the light sources to allow for emission of LCom signals. The luminaire may also include a controller configured to synchronize timing of the LCom signals. In some cases, one panel may be configured to emit an LCom signal that is the inverse or duplicate of the LCom signal emitted from another panel. Panel signal inversion may be used to maintain a relatively constant level of light output from the luminaire and/or to create a virtual fiducial to provide orientation information. Using a multiple panel luminaire to transmit data may also result in improved data transmission rates and transmission reliability.