| 摘要 |
The invention relates to an optical device comprising a radiation source (101) for producing a radiation beam and means (103, 106) for focusing the radiation beam on an information carrier (100) along an optical path. The radiation beam has a central axis, an outer envelope and an intensity distribution. The optical device further comprises, in the optical path, an optical component (104) designed for increasing the RIM intensity and thus the radio between the intensity near the envelope and the intensity near the central axis in that at least the radiation beam near the central axis is diffracted.
|
