| 摘要 |
A diffraction-optical component for providing a radiation-diffracting grating structure is proposed, comprising a surface wave device including a substrate 43, a surface wave source 47 excitable with an adjustable frequency for producing surface waves on a surface 45 of the substrate 43 and an interaction region 17 of the substrate surface 45 which is provided for the radiation to interact with a grating structure provided by the surface waves produced. To this end, the surface wave source 47 may have a directional characteristic and emits surface waves stronger in a preferred direction 53 than in a direction 54 opposite thereto, the surface wave source may comprises an electro-acoustic transducer which includes spaced apart sections for emitting surface waves at different wavelengths, an electro-acoustic transducer of the surface wave source may be operated as a voltage divider with an intermediate electrode, the frequency for exciting the surface wave source may be adjusted in response to a measuring signal which is obtained by a surface wave receiver 73, a surface wave damper 73, 87 may be provided in the form of an acousto-electric transducer,a closed propagation path may be provided for the surface waves and the grating structure may be formed by standing surface waves. Moreover, an exposure system is proposed which comprises such a diffraction-optical component and a radiation source.
|
