| 摘要 |
<p>The invention relates to a dual-field (small field and large field) imaging system including an optronic detector (1) and an optical combination of small field focalisation (Fpc) comprising on an optical axis: a head lens (G1); a small-field inlet pupil in the vicinity of the head lens; a real large-field inlet pupil, i.e. provided upstream the head lens; an intermediate focal plane (IFP); the optical combination further comprising on the optical axis the following dioptric groups: a convergent head group G1 having a focal F, with F<F<SUB>pc</SUB>/2, said G1 group including the head lens; a field changing divergent group G2 capable of displacement along the optical axis, said group being located upstream the IFP in a SF configuration and downstream the IFP in a LF configuration; a relay group G3 imaging the IFP on the focal plane of the detector. It comprises a cooled IR2 and IR3 detector and an optical combination including 6 lenses, including at least one diffractive lens, in the head group G1, and at least 3 different materials including CaF2 are used for the lenses of the head group G1.</p> |
