| 摘要 |
<p>An optical element can be placed in a finite or infinite ray path and be provided with spectral-selective filtering, at the same time compensating the resulting negative geometric-optic influence through corresponding compensation measures relevant to the image. The optical element has at least an optically effective, non-plane surface (25). It has for example the ability to absorb completely visible light (6) and to be completely transparent to light having shorter or longer wavelengths (Mr, Mb). Furthermore, a laser autofocus device known in itself is equipped with the optical element of the invention, thus allowing a dark field illumination (1) to be obtained with a reflected light microscope without losing the autofocus function.</p> |
