| 摘要 |
<p>PURPOSE: To prevent flickering, etc. by allowing changes in the position of a dimmer volume and changes in the luminance of a bulb to become linear even if the bulb itself has a nonlinear characteristic, and preventing the bulb from being overheated and decreased in life even if battery voltage fluctuates. CONSTITUTION: Input voltage data 'DPWM' is produced on the basis of an output voltage 'V0 ' output from a dimmer volume 3, by consulting the contents of an extinction-value correcting table in which extinction values showing the characteristic of a bulb 7 are stored and the contents of a battery correcting table in which is stored the correction required to keep constant time power applied to the bulb 7 even if battery voltage 'VBAT' fluctuates. The bulb 7 is dimmed and lighted at an input voltage having a duty ratio corresponding to the input voltage data 'DPWM'.</p> |
