Lamp e.g. gas-discharge lamp, brightness adjusting device for background lighting, has modulator applying voltage to lamp, such that voltage is sufficient and reduced during intervals, where transitions between intervals are decelerated

摘要

The device (10) has a pulse width modulation modulator (14), modification circuit (16), pulse width modulation circuit (18), bridge circuit (20), and transformer (22) for applying pulsed effective voltage to a fluorescent lamp (12), such that the effective voltage is sufficient during pulse in intervals for igniting the fluorescent lamp and is reduced during pulse out intervals for igniting the fluorescent lamp. The transitions between the pulse in intervals and pulse out intervals are decelerated. An independent claim is also included for a method for adjusting brightness of a background lighting.