CPC G02B 21/33 (2013.01) [G02B 21/0072 (2013.01); G02B 21/025 (2013.01)] | 21 Claims |
1. An objective, comprising:
a plurality of lenses arranged along an optical axis of the objective,
wherein:
the objective is an immersion objective;
the objective comprises a correction group which comprises at least one of the plurality of lenses;
the correction group is displaceable along the optical axis;
the objective has a working distance that is dependent on at least one member selected from the group consisting of an immersion medium and a cover glass that may be used;
aberrations of a wavefront coming from an axis point are describable by Zernike polynomials with Zernike coefficients;
the Zernike coefficient Z4 has a sensitivity Z4sens with respect to a displacement of the correction group along the optical axis;
the Zernike coefficient Z9 has a sensitivity Z9sens with respect to the displacement of the correction group along the optical axis; and
|Z4sens:Z9sens|<1.
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