Optical scope

An optical scope, comprising:

• an objective lens;
• an eyepiece lens;
• a reticle disposed between the objective lens and the eyepiece lens;
• an erecting optical system that erects an image and is disposed between the objective lens and the reticle;
• and
• a field lens having negative power disposed between the eyepiece lens and the erecting optical system, wherein
• a straight imaginary line is defined from a center of the objective lens to a center of the eyepiece lens,
• the reticle, the erecting optical system, and the field lens are arranged such that the imaginary line intersects each of the reticle, the erecting optical system, and the field lens respectively,
• the eyepiece lens comprises a plurality of lens structures, and
• the objective lens, the field lens, the reticle and the eyepiece lens are arranged in sequence.

A method of forming an optical scope, comprising:

• providing an objective lens;
• providing an eyepiece lens, wherein the eyepiece lens comprises a plurality of lens structures, each lens structure having either positive power or negative power, wherein the plurality of lens structures comprise a first lens structure having a positive power, a second lens structure, a third lens structure, and a fourth lens structure;
• placing a reticle between the objective lens and the eyepiece lens;
• placing an erecting optical system that erects an image between the objective lens and the reticle;
• placing a field lens having negative power disposed between the eyepiece lens and the erecting optical system;
• defining a straight imaginary line from a center of the objective lens to a center of the eyepiece lens;
• arranging the reticle, the erecting optical system, and the field lens such that the imaginary line intersects each of the reticle, the erecting optical system, and the field lens respectively.