| CPC G02B 13/06 (2013.01) [G02B 9/64 (2013.01); G02B 13/0045 (2013.01); G02B 27/0025 (2013.01); H04N 23/55 (2023.01)] | 17 Claims |
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1. A wide-angle lens, from an object side to an imaging surface, sequentially comprising:
a first group with a negative refractive power, the first group comprising a first lens, a second lens and a third lens from the object side to the imaging surface, wherein the first lens has a negative refractive power, a convex object side surface and a concave image side surface, the second lens has a negative refractive power and a concave image side surface, the third lens has a negative refractive power;
a stop;
a second group with a positive refractive power, the second group comprising a fourth lens and a fifth lens from the object side to the imaging surface, wherein the fourth lens has a positive refractive power and a convex image side surface, the fifth lens has a positive refractive power and a convex image side surface;
a third group with a positive refractive power, the third group comprising a sixth lens, a seventh lens, and an eighth lens from the object side to the imaging surface, wherein the sixth lens and the seventh lens are cemented to form a cemented doublet, the eighth lens has a positive refractive power, a convex object side surface and a convex image side surface; and
a filter, disposed between the third group and the imaging surface;
wherein the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are glass lenses;
wherein the wide-angle lens meets the expression:
0.0494(mm/°≤IH/θ≤)0.05(mm/°;
where θ represents a half field of view of the wide-angle lens, and IH represents a half actual image height of the wide-angle lens.
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