| 摘要 |
PROBLEM TO BE SOLVED: To provide an illumination system that includes an array of reflecting elements, which may be realized as a microelectromechanical system (MEMS), particularly as a digital micromirror device (DMD).SOLUTION: An illumination system for illuminating a mask 16 in a microlithographic exposure apparatus has an optical axis 60 and a pupil surface 70. The system comprises a beam deflection array 46 of reflective or transparent beam deflection elements (M) such as mirrors, and each deflection element (M) is adapted to deflect an impinging light ray by a deflection angle that is variable in response to a control signal. The system further comprises an optical raster element 34 including a plurality of microlenses and/or diffractive structures. The beam deflection elements (M), which are arranged in a first plane 40, and the optical raster element 34, which is arranged in a second plane 36, commonly produce a two-dimensional far field intensity distribution. An optical imaging system 38, 41 optically conjugates the first plane 40 to the second plane 34. |
