Scope

A scope comprising:

• an objective lens system which is with refractive power;
• a relay lens system which is with refractive power and comprises a first lens group, a second lens group, and a third lens group;
• and
• an eyepiece system which is with refractive power;
• wherein the first lens group is with positive refractive power;
• wherein the second lens group comprises a II-2-1 lens and a II-2-2 lens having a convex surface facing an object side, and both of which are cemented and the II-2-1 lens is a meniscus lens;
• wherein the third lens group comprises a II-3-1 lens and a II-3-2 lens having a convex surface facing an image side, and both of which are cemented;
• wherein the second lens group and the third lens group can move along an optical axis to change a magnification of the relay lens system and thereby change a magnification of the scope;
• wherein the objective lens system, the relay lens system, and the eyepiece system are arranged in order from the object side to the image side along the optical axis;
• wherein the first lens group, the second lens group, and the third lens group are arranged in order from the object side to the image side along the optical axis;
• wherein the II-2-1 lens, the II-2-2 lens, the II-3-1 lens, and the II-3-2 lens are arranged in order from the object side to the image side along the optical axis;
• wherein the scope satisfies:
• 20 degrees≤FOV×MEL≤24 degrees;
• wherein FOV is a field of view of the scope and ME, is a magnification of the relay lens system.