Fish eye lens assembly - comprises three lens group, first lens in first group being a convex negative meniscus

摘要

The fish eye lens has a first lens-side lens group (G1) consisting of at least two lenses (L1,L3), of which the first (L1) is formed as a convex, negative meniscus. A second lens group (G2) comprises at least one lens (L3) and a shutter, and a picture-side lens group (G3) comprising at least three lenses. The first lens (L1) of the first lens group (G1) has a ratio between the first radius and the focus of 8.5 less than r1/f less than 11.8. The refraction index nl of the first lens (L1) is less than 1.625 and the ratio of the total focus fGl of the first lens group to the focus f lies in the range 1.1 less than fGl/f less than 2.1. The second lens group (G2) comprises at least four lenses, the last two lenses of which having adjacent radii in the range 1.21 less than r less than 1.28. The third lens group f(G3) comprises at least three lenses, whereby the ratio of the total focus to the focus fG3 of the third lens group is in the range 2.8 less than fG3/f less than 3.2. USE - A fish eye lens assembly.