Abstract:
The invention relates to a method of representing a video image based on a video signal by means of a projector which comprises an image display device and a high-pressure gas discharge lamp, which lamp is supplied with a square-wave alternating current (I 0 , I 10 ) on which a current pulse (P 1 , P 3 , P 10 , P 40 ) is superimposed before each phase reversal. According to the invention, the alternating current (I 0 , I 10 ) is superimposed with a second current pulse (P 2 , P 4 , P 20 , P 30 , P 50 , P 60 ) of the same polarity. A simple attunement of the alternating current frequency to the image frequency without image artifacts is made possible by the second pulses (P 2 , P 4 , P 20 , P 30 , P 50 , P 60 ).
Abstract:
An average power consumption of receiving units (3,5,7) for controlling apparatuses (4,6,8) in response to operation control signals from transmitting units (2) may be reduced by introducing devices (1,21) for controlling the power consumption of the receiving units (3,5,7) in response to detections of states of the apparatuses (4,6,8). The devices (1) may comprise controllers (30) for controlling the power consumption in a wireless, non-wireless, physical and/or logical manner. The devices (1) may comprise monitors (33) for monitoring power consumption, currents and/or voltages at the receiving units (3,5,7) and/or the apparatuses (4,6,8). The devices (1) may comprise receivers (40), detectors (41), converters (42) and transmitters (43) for receiving the operation control signals, detecting the states of the apparatuses (4,6,8), converting the operation control signals into converted signals, and transmitting the operation control signals or the converted signals to the receiving units (3,5,7) for controlling the power consumption of the receiving units (3,5,7) via the transmitted signals, wherein the transmitted signals correspond to power control signals.