| 摘要 |
PURPOSE:To obtain easily a laterally long rectangular type wide screen and to improve the utilization rate of luminous flux by allowing light beams from adjacent xenon short arc lamps to overlap each other on the screen. CONSTITUTION:Two xenon short arc lamps 1 are arranged in the lengthwise direction of the screen 5. The 2nd focal points of their elliptic converging mirros 2 are both positioned near the center of a projection lens 4. Therefore, the light from the upper lamp 1 is reflected and converged by the elliptic converging mirror 2 to reach a point between points P and Q on the screen 5 through the projection lens 4. The illuminance distribution on the screen 5 in the lengthwise direction X-X has a sufficiently high-illuminance area. Consequently, the long rectangular type wide screen is obtained easily and the utilization rate of light is improved. |
