PURPOSE: To obtain a compact and large aperture photographing lens whose various abberations are effectively corrected by arranging the 1st to 7th lenses and satisfying specific conditions.
CONSTITUTION: The 1st meniscus-shape lens having positive refractive power, the 2nd meniscus-shape lens having positive refractive power, the 3rd meniscus- like lens having negative refractive power, the 4th lens having negative refractive power, the 5th lens having positive refractive power, the 6th meniscus-like lens having negative refractive power, and the 7th lens having positive refractive power are successively arranged from the front. When it is defined that (ri) is the radius of curvature of the i-th lens surface counted from the front, (di) is lens thickness or an air gap on the axis of the i-th lens counted from the front, (ni) is the refractive index of a cutting material for the i-th single lens counted from the front, (fi) is the focal distance of the i-th lens group counted from the front, and (f) is the focal distance of the whole system, conditions expressed by inequalities I to IV are satisfied.
JP3069437 | [Title of Invention] Fixed Focal Length Lens |
WO/2020/184871 | IMAGING LENS |
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