| 摘要 |
PURPOSE:To adjust the variance of the quantity of light easily, quickly, and properly, by providing a light quantity adjusting mechanism and rotating a lamp around the lamp axis to adjust the quantity of light. CONSTITUTION:A lamp 3 which has a filament 2 extending in the direction traversing a lamp axis 1 is used, and a light quantity adjusting mechanism is constituted with gears 7 and 8 and a pulse motor 10. In this case, when the pulse motor 10 is rotated by an external signal for adjustment, the lamp 3 is rotated by a driving quantity of this signal, and the projection area of the filament 2 through a condenser lens 4 and a main lens 5 is changed in the longitudinal direction of a slit 6, and the quantity of light incident to the main lens 5 is changed by this variation to obtain the aperture effect. By providing this light quantity adjusting mechanism, the quantity of light is adjusted with a constant lamp voltage, and the adjustment is performed quickly with a simple structure. |
