| 摘要 |
PROBLEM TO BE SOLVED: To actualize the lamp illumination control method which can extend the time for an exposing process within the life time of a lamp by reducing the power consumption and making the service life of the lamp long. SOLUTION: Exposure light emitted by the lamp 1 is converged by a converging mirror 2, passed through a 1st plane mirror 3, an integrator lens 4, a shutter 5, and a collimator 6, and emitted by a light irradiation device 10. A work is irradiated with the exposure light emitted by the light irradiation device 10 through an unillustrated mask, and the work is exposed. A lamp power circuit 12 which supplies the electric power to the lamp 1 is provided with a switching circuit 12a to input the rated electric power to the lamp, when the work is exposed and inputs electric power which is smaller than the rated electric power, e.g. electric power which is 50 to 80% of the rated electric power to the lamp. |
