| 摘要 |
<p>Optical resolution of an objective (11) is improved by splitting one or more beams (12) of electromagnetic radiation into a plurality of separate beams (15, 16) in a beam splitting device (13) which may be a glass part, transmitting and part-reflecting device or a birefringent material. Interference at the image may be alleviated by advancing or retarding the separate beams so that they are all in phase at a given angle, for example using the birefringent material. The separate beams (15, 16) emerge from the beam-splitting device (13) in the form of a wider composite beam which may be focussed by a lens (18). Any number of separate beams may be produced in one or two dimensions.</p> |
