摘要 |
An exposure apparatus which projects exposure light from a pattern of an illuminated original onto a substrate, comprises a projection system including an optical element and configured to project the exposure light onto the substrate, an enclosure configured to enclose the projection system, and a cleaning mechanism configured to clean the optical element by irradiating the optical element with ultraviolet light under an environment in which oxygen is present within the enclosure, the cleaning mechanism including a light source configured to generate ultraviolet light, a tubular member including an exit window and configured to partially enclose an optical path between the light source and the optical element, and a regulating device configured to regulate an environment of a space inside the tubular member so that a partial pressure of oxygen becomes lower in the space inside the tubular member than in a space which is outside the tubular member. |