摘要:
A method for driving a lamp with a variable duty cycle in a timing relationship with an input image signal (Si) comprises the steps of: receiving the image signal having a predetermined frame period (t3−t1); generating a high-frequency inverter signal (Sv); based on the received image signal, generating a dimming command signal (Sdcc) determining a target ON time (t1) for the lamp and determining a target OFF time (t2) for the lamp, such that the duty cycle (Δ=(t2−t1)/(t3−t1)) has a desired value; on the basis of the target ON time, determining an adapted ON time (ti 1) coinciding with a first predetermined phase of the high-frequency inverter signal; on the basis of the target OFF time, determining an adapted OFF time (t12) coinciding with a second predetermined phase of the inverter signal; switching the lamp ON at the adapted ON time and switching the lamp OFF at the adapted OFF time.
摘要:
A charger for inductively charging one or more battery powered appliances simultaneously includes an external unit configured to inductively provide power to the battery powered appliances. The external unit includes two or more primary coil pairs that are arranged in a circular pattern; an AC power source for providing an alternating current (AC) to the primary coil pairs for generating a rotating magnetic field between respective primary coils of the primary coil pairs; and a processor for driving the AC power source. The one or more battery powered appliances are configured to be arranged inside the circular pattern of the external unit. Further, each appliance includes a secondary coil for enclosing part of the magnetic field and, in response, generating a current for charging the battery of the appliance.
摘要:
A wake-up lighting device is described, comprising a gas discharge lamp (10) and a lamp driver (1; 2) comprising a power source (100) capable of generating spaced-apart current bursts (51) of alternating lamp current (I). The wake-up lighting device is capable of operating in an off-mode in which no lamp current is generated, and is adapted to switch from its off-mode to a wake-up mode in which the power source (100) operates to:—initially generate an alternating lamp current (I) with a minimum duty cycle value (ΔT) and a reduced current amplitude (IR) close to zero;—subsequently gradually increase the current amplitude while keeping the duty cycle (Δ) constant at the minimum duty cycle value (ΔT), until the current amplitude reaches a nominal current amplitude (IM);—subsequently gradually increase the duty cycle (Δ) while keeping the current amplitude constant at the nominal current amplitude (IM).
摘要:
The present invention provides a charger for inductively charging one or more battery powered appliances simultaneously. The charger comprises an external unit adapted to inductively provide power to the battery powered appliances, the external unit comprising: two or more primary coil pairs that are arranged in a circular pattern; an AC power source for providing an alternating current (AC) to the primary coil pairs for generating a rotating magnetic field between respective primary coils of the primary coil pairs; and a processor for driving the AC power source, wherein the one or more battery powered appliances are adapted to be arranged inside the circular pattern of the external unit, each appliance comprising a secondary coil for enclosing part of the magnetic field and in response generating a current for charging the battery of the appliance.