| CPC G02B 15/144113 (2019.08) [G02B 15/144105 (2019.08)] | 20 Claims |

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1. A zoom lens, comprising:
a first lens group comprising lenses, wherein the first lens group is fixedly disposed along an object side of an optical axis, wherein a first lens of the lenses is a biconvex lens, and wherein at least two lenses of the lenses are glass lenses;
a second lens group adjacent to the first lens group and disposed along the optical axis, wherein the second lens group is configured to move along the optical axis;
a third lens group fixedly disposed and adjacent to the second lens group along the optical axis; and
a fourth lens group adjacent to the third lens group and disposed along the optical axis, wherein the fourth lens group is a compensation group and is configured to move along the optical axis,
wherein the first lens group, the second lens group, the third lens group, and the fourth lens group are sequentially arranged from the object side to an image side along the optical axis,
wherein the first lens group, the third lens group, and the fourth lens group have a positive focal power, and wherein the second lens group has a negative focal power,
wherein the second lens group is a focusing group and the fourth lens group is a compensation group that is configured to move along the optical axis with the second lens group, or the fourth lens group is a focusing group and the second lens group is a compensation group that is configured to move along the optical axis with the fourth lens group,
wherein a maximum clear aperture diameter of the zoom lens meets the following relationship: 4 millimeters (mm)≤φ≤12 mm, and
wherein φ is the maximum clear aperture diameter of the zoom lens.
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