| 摘要 |
PURPOSE:To make it possible to suppress the change in color temp. and luminous intensity distribution with the change in the quantity of emitted light to a predetermined range by enabling the stepless adjustment of the quantity of emitted light, by successively fully lighting each block and lighting only one block in a power controlling manner. CONSTITUTION:An incandescent electric lamp 3 is separated into first, second n-th blocks and first, second i-th blocks are lighted and only (i+1)th block is lighted in a power controlling manner. By this method, the stepless adjustment of the quantity of emitting light is enabled and the change in color temp. and luminous intensity distribution with the change in the quantity of emitted light can be suppressed to a range generating no problem from a practical viewpoint.
|
