| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve the luminance of a display lamp while keeping constant current consumption by controlling only the display lamp to be turned on among plural display lamps through a dynamic turning-on means. SOLUTION: When respective display lamps 4 (#1-#4) are turned on, a dynamic turning-on circuit 3 flickers the respective display lamps 4 in a cycle sensible for human being. At such a time, the dynamic turning-on circuit 3 divides the plural display lamps 4 into several groups and provides a time difference in the cycle for controlling the ON of display lamps 4 in each group so that even when the plural display lamps 4 in all the groups are simultaneously turned on, a peak current can be suppressed and the current consumption can be kept constant. A dynamic turning-on control circuit 2 controls only the display lamp 4 to be turned on among the plural display lamps 4 through the dynamic turning-on circuit 3. Thus, since the dynamic turning-on circuit 3 excludes the turned-off display lamp 4 from the object of control, control is made efficient.</p> |
