| 摘要 |
<p>A circuit (300) and method for controlling the brightness of a display screen (200) implemented using a flat panel field emission display (FED) screen (200). A brightness control circuitry (300) is positioned across the row drivers (220) for altering the applied voltage (212) to the rows (230) causing a change in brightness cross the FED screen (200). The applied voltage (212) can be pulse width modulated or amplitude modulated to alter the brightness of the FED screen (200). Within one FED screen (200) implementation, it is more efficient to alter the row voltage (212); however, in alternative embodiment of the present invention the column voltages (207) are modulated in amplitude or pulse width to alter the brightness of the FED screen (200). The brightness control circuitry (300) of the present invention can be made responsive to a manual brightness knob (520) or can be responsive to an ambient light sensor (580a, 580b).</p> |
