Variable power endoscope

Claim 2

An endoscope including an intermediate image-forming optical system and an ocular optical system, said ocular optical system having variable magnifying power and being constructed according to the following table n v ao 38.4-21.5 r1 infinity a1 3 1.519 64.0 r2 -14.45 a2 10.75-27.65 r3 +11.2 a33.8 1.610 59.2 r4 -13.13 a4 0.8 1.678 32.0 r5 infinity wherein all linear dimensions are given in millimeters, r1 through r5 represent the successive radii of curvature of the surfaces of the lens elements, commencing with the lens surface nearest the intermediate image-forming optical system, ao through a4 representing the successive distances between the vertices of the lens surfaces measured along the axis of the ocular optical system, ao being the distance between the adjacent vertices of the most closely adjacent lenses of said systems, n denotes the index of refraction of the glasses of the lens elements, and v represents the Abbe number of the glasses of the lens elements, the magnifications of said ocular optical system being related by a factor of 1.82, and the focal length f'' varying between 14.9 and 27.1 millimeters.

Claim 3

An endoscope including an intermediate image-forming optical system and an ocular optical system, said ocular optical system having variable magnifying power and being constructed according to the following table n v ao 30.95-20.53 r1 -25.93 a1 1.5 1.519 64.0 r2 Infinity a2 3.2-23.62 r3 Infinity a3 3 1.519 64.0 r4 -14.45 a416-6 r5 +11.2 a5 3.8 1.610 59.2r6 -13.13 a6 0.81.67832.0 r7 Infinity wherein all linear dimensions are given in millimeters, r1 through r7 represent the successive radii of curvature of the surfaces of the lens elements commencing with the lens surface nearest the inTermediate image-forming optical system, ao through a6 represent the successive distances between the vertices of the lens surfaces measured along the axis of the ocular optical system, ao being the distance between the adjacent vertices of the most closely adjacent lenses of said systems, n denotes the index of retraction of the glasses of the lens elements, and v represents the Abbe number of the glasses of the lens elements, the extreme magnifications of said ocular optical system being related by a factor of 1.68, and the focal length f'' varying between 9.86 and 16.53 millimeters.

Claim 4

An endoscope including an intermediate image-forming optical system and an ocular optical system, said ocular optical system having variable magnifying power and being constructed according to the following table n v ao 30.95-20.53 r1 -25.93 a1 1.5 1.519 64.0 r2 Infinity a2 3.2-23.62 r3 Infinity a3 3 1.519 64.0 r4 -14.45 a416-6 r5 +11.2 a5 3.8 1.610 59.2r6 -13.13 a6 0.81.67832.0 r7 Infinity wherein all linear dimensions are given in millimeters, r1 through r7 represent the successive radii of curvature of the surfaces of the lens elements commencing with the lens surface nearest the inTermediate image-forming optical system, ao through a6 represent the successive distances between the vertices of the lens surfaces measured along the axis of the ocular optical system, ao being the distance between the adjacent vertices of the most closely adjacent lenses of said systems, n denotes the index of retraction of the glasses of the lens elements, and v represents the Abbe number of the glasses of the lens elements, the extreme magnifications of said ocular optical system being related by a factor of 1.68, and the focal length f'' varying between 9.86 and 16.53 millimeters.

Claim 5

An endoscope including an intermediate image-forming optical system and an ocular optical system, said intermediate image-forming optical system comprising a variable power system constructed according to the following table n v ao 12.66-31.66-56-66 r1 +74.42a1 2 1.618 50.8 r2 -9.7 a2 1.21.734 28.1 r3 -22.65 a3 54-60-54 r4 22.65 a4 1.2 1.734 28.1 r5 +9.7 a5 2 1.618 50.8 r6 -74.42 ab 58.32-33.32- 14.32 wherein all linear dimensions are given in millimeters, r1 through r6 represent the successive radii of curvature of the surfaces of the lens elements commencing with the lens surface most remote from the eyepiece of the endoscope, ao through ab represent the successive distances between the vertices of the lens surfaces measured along the axis of the endoscope, ao being the distance between the adjacent vertices of the lens of said variable magnifying power system which is most remote from the eyepiece of the endoscope and the lens most closely adjacent it, in the direction toward the objective, n denotes the index of refraction of the glasses of the lens elements, and v represents the Abbe number of the glasses of the lens elements, the extreme magnification factors of said variable power optical system being related by a factor of 1.73.

Claim 6

An endoscope including an intermediate image-forming optical system and an ocular optical system, said intermediate image-forming optical system comprising a variable power system constructed according to the following table n v ao 12.66-31.66-56-66 r1 +74.42a1 2 1.618 50.8 r2 -9.7 a2 1.21.734 28.1 r3 -22.65 a3 54-60-54 r4 22.65 a4 1.2 1.734 28.1 r5 +9.7 a5 2 1.618 50.8 r6 -74.42 ab 58.32-33.32- 14.32 wherein all linear dimensions are given in millimeters, r1 through r6 represent the successive radii of curvature of the surfaces of the lens elements commencing with the lens surface most remote from the eyepiece of the endoscope, ao through ab represent the successive distances between the vertices of the lens surfaces measured along the axis of the endoscope, ao being the distance between the adjacent vertices of the lens of said variable magnifying power system which is most remote from the eyepiece of the endoscope and the lens most closely adjacent it, in the direction toward the objective, n denotes the index of refraction of the glasses of the lens elements, and v represents the Abbe number of the glasses of the lens elements, the extreme magnification factors of said variable power optical system being related by a factor of 1.73.