| 摘要 |
<p>A monochromator assembly (10) comprising a premonochromator (12) and a main monochromator (14) in which the main monochromator (14) receives light from the exit slit (26) of the premonochromator (12). The premonochromator includes an adjustable dispersive element, preferably a prism (30), and focussing means (32) for focussing a selected band of wavelengths of light from a source (20) in the form of an image (36, 38, 40, 42) of the premonochromator's entrance slit (16) onto the exit slit (26). The entrance slit (16) of the premonochromator (12) is significantly wider than its exit slit (26) and the dispersive element (30) is further finely adjustable for moving the image of the entrance slit across the exit slit. Thus the dispersive element of the premonochromator provides for "order sorting" of the dispersed wavelengths and via the fine adjustment provides for selection of light emanating from a narrow spatial region of the light source for passage through the exit slit and into the main monochromator.</p> |
