Ocular optical system

Claim 2

An ocular optical system having a wide diopter adjustment range comprising, in order from the viewing side, a first lens component having a negative refracting power, a second lens component having a positive refracting power, a third lens component having a negative refracting power, a pentaprism, and a condenser lens component, wherein the second lens having the positive refracting power is movable for diopter adjustment, said optical system satisfying the following conditions: F.sub.1 <0, 0.7F<|F.sub.1 |<F, (1) 0.35F<F.sub.1.2 <0.55F, and (2) 1.4<(ν.sub.2 +ν.sub.3)/(ν.sub.1 +ν.sub.4)<1.8, (3) where F is the overall focal length of the optical system, F 1 .2 . . . i is the resultant focal length up to the i-th lens group, and ν i is the Abbe number of the i-th lens from the viewing side.

Claim 3

An ocular optical system having a wide diopter adjustment range comprising, in order from the viewing side, a first lens component having a negative refracting power, a second lens component having a positive refracting power, a third lens component having a negative refracting power, a penta prism and a condenser lens component wherein the second lens component having the positive refracting power is movable for diopter adjustment, said optical system satisfying the following conditions: ______________________________________ F = 60.944 r.sub.1 -55.766 d.sub.1 0.80 n.sub.1 1.76180 ν.sub.1 27.1 r.sub.2 157.248 d.sub.2 1.96 r.sub.3 -211.982 d.sub.3 4.37 n.sub.2 1.83400 ν.sub.2 37.2 r.sub.4 -33.560 d.sub.4 0.20 r.sub.5 52.212 d.sub.5 3.58 n.sub.3 1.83481 ν.sub.3 39.6 r.sub.6 -55.371 d.sub.6 2.32 r.sub.7 -65.300 d.sub.7 1.72 n.sub.4 1.84666 ν.sub.4 23.9 r.sub.8 82.225 d.sub.8 1.33 r.sub.9 ∞ d.sub.9 81.09 n.sub.5 1.51633 ν.sub.5 64.1 r.sub.10 ∞ d.sub.10 1.00 r.sub.11 78.000 d.sub.11 3.50 n.sub.6 1.80518 ν.sub.6 25.4 r.sub.12 ∞ d.sub.12 1.60 (1) F.sub.1 = -0.8852F (2) F.sub.1·2 = 0.4319F (3) (ν.sub.2 + ν.sub.3)/(ν.sub.1 + ν.sub.4) = 1.569 diopter d.sub.2 d.sub.6 -2.5 D 4.06 0.22 1.5 D 0.49 3.79 ______________________________________ where F is the overall focal length of the optical system, F 1 .2 . . . i is the resultant focal length up to the i-th lens component, and ν 1 is the Abbe number of the i-th lens from the viewing side, r i is the radius of curvature of the i-th lens from the viewing side, d i is the difference between adjacent lenses or the lens thickness of the i-th lens from the viewing side, and N i is the refractive index at the d-line of the i-th lens from the viewing side.

Claim 4

An ocular optical system having a wide diopter adjustment range comprising, in order from the viewing side, a first lens component having a negative refracting power, a second lens component having a positive refracting power, a third lens component having a negative refracting power, a penta prism and a condenser lens component wherein the second lens component having the positive refracting power is movable for diopter adjustment, said optical system satisfying the following conditions: ______________________________________ F = 60.944 r.sub.1 -55.766 d.sub.1 0.80 n.sub.1 1.76180 ν.sub.1 27.1 r.sub.2 157.248 d.sub.2 1.96 r.sub.3 -211.982 d.sub.3 4.37 n.sub.2 1.83400 ν.sub.2 37.2 r.sub.4 -33.560 d.sub.4 0.20 r.sub.5 52.212 d.sub.5 3.58 n.sub.3 1.83481 ν.sub.3 39.6 r.sub.6 -55.371 d.sub.6 2.32 r.sub.7 -65.300 d.sub.7 1.72 n.sub.4 1.84666 ν.sub.4 23.9 r.sub.8 82.225 d.sub.8 1.33 r.sub.9 ∞ d.sub.9 81.09 n.sub.5 1.51633 ν.sub.5 64.1 r.sub.10 ∞ d.sub.10 1.00 r.sub.11 78.000 d.sub.11 3.50 n.sub.6 1.80518 ν.sub.6 25.4 r.sub.12 ∞ d.sub.12 1.60 (1) F.sub.1 = -0.8852F (2) F.sub.1·2 = 0.4319F (3) (ν.sub.2 + ν.sub.3)/(ν.sub.1 + ν.sub.4) = 1.569 diopter d.sub.2 d.sub.6 -2.5 D 4.06 0.22 1.5 D 0.49 3.79 ______________________________________ where F is the overall focal length of the optical system, F 1 .2 . . . i is the resultant focal length up to the i-th lens component, and ν 1 is the Abbe number of the i-th lens from the viewing side, r i is the radius of curvature of the i-th lens from the viewing side, d i is the difference between adjacent lenses or the lens thickness of the i-th lens from the viewing side, and N i is the refractive index at the d-line of the i-th lens from the viewing side.

Claim 5

An ocular optical system having a wide diopter adjustment range comprising, in order from the viewing side, a first component having a negative refracting power, a second lens component having a positive refracting power, a third lens component having a negative refracting power, a penta prism and a condenser lens component wherein the second lens component having the positive refracting power is movable for diopter adjustment, said optical system satisfying the following conditions: ______________________________________ F = 61.249 r.sub.1 -52.604 d.sub.1 0.80 n.sub.1 1.76180 ν.sub.1 27.1 r.sub.2 131.327 d.sub.2 2.34 r.sub.3 -211.969 d.sub.3 3.79 n.sub.2 1.83400 ν.sub.2 37.2 r.sub.4 -31.796 d.sub.4 0.20 r.sub.5 55.359 d.sub.5 3.65 n.sub.3 1.83481 ν.sub.3 42.7 r.sub.6 -50.886 d.sub.6 2.73 r.sub.7 -67.402 d.sub.7 1.32 n.sub.4 1.84666 ν.sub.4 23.9 r.sub.8 73.364 d.sub.8 1.45 r.sub.9 ∞ d.sub.9 81.09 n.sub.5 1.51633 ν.sub.5 64.1 r.sub.10 ∞ d.sub.10 1.00 r.sub.11 78.000 d.sub.11 3.50 n.sub.6 1.80518 ν.sub.6 25.4 r.sub.12 ∞ d.sub.12 1.60 (1) F.sub.1 = -0.8034F (2) F.sub.1·2 = 0.4234F (3) (ν.sub.2 + ν.sub.3)/(ν.sub.1 + ν.sub.4) = 1.569 diopter d.sub.2 d.sub.6 -3.0 D 4.84 0.23 1.5 D 0.81 4.26 ______________________________________ where F is the overall focal length of the optical system, F 1 .2 . . . i is the resultant focal length up to the i-th lens component, and ν i is the Abbe number of the i-th lens from the viewing side, r i is the radius of curvature of the i-th lens from the viewing side, d i is the distance between adjacent lenses or the lens thickness of the i-th lens from the viewing side, and N i is the refractive index at the d-line of the i-th lens from the viewing side.

Claim 6

An ocular optical system having a wide diopter adjustment range comprising, in order from the viewing side, a first component having a negative refracting power, a second lens component having a positive refracting power, a third lens component having a negative refracting power, a penta prism and a condenser lens component wherein the second lens component having the positive refracting power is movable for diopter adjustment, said optical system satisfying the following conditions: ______________________________________ F = 61.249 r.sub.1 -52.604 d.sub.1 0.80 n.sub.1 1.76180 ν.sub.1 27.1 r.sub.2 131.327 d.sub.2 2.34 r.sub.3 -211.969 d.sub.3 3.79 n.sub.2 1.83400 ν.sub.2 37.2 r.sub.4 -31.796 d.sub.4 0.20 r.sub.5 55.359 d.sub.5 3.65 n.sub.3 1.83481 ν.sub.3 42.7 r.sub.6 -50.886 d.sub.6 2.73 r.sub.7 -67.402 d.sub.7 1.32 n.sub.4 1.84666 ν.sub.4 23.9 r.sub.8 73.364 d.sub.8 1.45 r.sub.9 ∞ d.sub.9 81.09 n.sub.5 1.51633 ν.sub.5 64.1 r.sub.10 ∞ d.sub.10 1.00 r.sub.11 78.000 d.sub.11 3.50 n.sub.6 1.80518 ν.sub.6 25.4 r.sub.12 ∞ d.sub.12 1.60 (1) F.sub.1 = -0.8034F (2) F.sub.1·2 = 0.4234F (3) (ν.sub.2 + ν.sub.3)/(ν.sub.1 + ν.sub.4) = 1.569 diopter d.sub.2 d.sub.6 -3.0 D 4.84 0.23 1.5 D 0.81 4.26 ______________________________________ where F is the overall focal length of the optical system, F 1 .2 . . . i is the resultant focal length up to the i-th lens component, and ν i is the Abbe number of the i-th lens from the viewing side, r i is the radius of curvature of the i-th lens from the viewing side, d i is the distance between adjacent lenses or the lens thickness of the i-th lens from the viewing side, and N i is the refractive index at the d-line of the i-th lens from the viewing side.

Claim 7

An ocular optical system having a wide diopter adjustment range comprising, in order from the viewing side, a first lens component having a negative refracting power, a second lens component having a positive refracting power, a third lens component having a negative refracting power, a penta prism and a condenser lens component wherein the second lens component having the positive refracting power is movable for diopter adjustment, said optical system satisfying the following conditions: ______________________________________ F = 62.209 r.sub.1 -50.743 d.sub.1 0.81 n.sub.1 1.76180 ν.sub.1 27.1 r.sub.2 117.935 d.sub.2 2.78 r.sub.3 -179.820 d.sub.3 2.88 n.sub.2 1.83400 ν.sub.2 37.2 r.sub.4 -32.352 d.sub.4 0.10 r.sub.5 52.848 d.sub.5 3.89 n.sub.3 1.83481 ν.sub.3 42.7 r.sub.6 -51.064 d.sub.6 3.64 r.sub.7 -61.451 d.sub.7 0.79 n.sub.4 1.84666 ν.sub.4 23.9 r.sub.8 89.437 d.sub.8 1.33 r.sub.9 ∞ d.sub.9 81.09 n.sub.5 1.51633 ν.sub.5 64.1 r.sub.10 ∞ d.sub.10 1.00 r.sub.11 78.000 d.sub.11 3.50 n.sub.6 1.80518 ν.sub.6 25.4 r.sub.12 ∞ d.sub.12 1.60 (1) F.sub.1 = -0.7471 (2) F.sub.1·2 = 0.4339 (3) (ν.sub.2 + ν.sub.3)/(ν.sub.1 + ν.sub.4) = 1.569 diopter d.sub.2 d.sub.6 -3.0 D 5.61 0.82 1.5 D 0.81 5.54 ______________________________________ where F is the overall focal length of the optical system, F 1 .2 . . . i is the resultant focal length up to the i-th lens component, and ν i is the Abbe number of the i-th lens from the viewing side, r i is the radius of curvature of the i-th lens from the viewing side, d i is the distance between adjacent lenses or the lens thickness of the i-th lens from the viewing side, and N i is the refractive index at the d-line of the i-th lens from the viewing side.

Claim 8

An ocular optical system having a wide diopter adjustment range comprising, in order from the viewing side, a first lens component having a negative refracting power, a second lens component having a positive refracting power, a third lens component having a negative refracting power, a penta prism and a condenser lens component wherein the second lens component having the positive refracting power is movable for diopter adjustment, said optical system satisfying the following conditions: ______________________________________ F = 62.209 r.sub.1 -50.743 d.sub.1 0.81 n.sub.1 1.76180 ν.sub.1 27.1 r.sub.2 117.935 d.sub.2 2.78 r.sub.3 -179.820 d.sub.3 2.88 n.sub.2 1.83400 ν.sub.2 37.2 r.sub.4 -32.352 d.sub.4 0.10 r.sub.5 52.848 d.sub.5 3.89 n.sub.3 1.83481 ν.sub.3 42.7 r.sub.6 -51.064 d.sub.6 3.64 r.sub.7 -61.451 d.sub.7 0.79 n.sub.4 1.84666 ν.sub.4 23.9 r.sub.8 89.437 d.sub.8 1.33 r.sub.9 ∞ d.sub.9 81.09 n.sub.5 1.51633 ν.sub.5 64.1 r.sub.10 ∞ d.sub.10 1.00 r.sub.11 78.000 d.sub.11 3.50 n.sub.6 1.80518 ν.sub.6 25.4 r.sub.12 ∞ d.sub.12 1.60 (1) F.sub.1 = -0.7471 (2) F.sub.1·2 = 0.4339 (3) (ν.sub.2 + ν.sub.3)/(ν.sub.1 + ν.sub.4) = 1.569 diopter d.sub.2 d.sub.6 -3.0 D 5.61 0.82 1.5 D 0.81 5.54 ______________________________________ where F is the overall focal length of the optical system, F 1 .2 . . . i is the resultant focal length up to the i-th lens component, and ν i is the Abbe number of the i-th lens from the viewing side, r i is the radius of curvature of the i-th lens from the viewing side, d i is the distance between adjacent lenses or the lens thickness of the i-th lens from the viewing side, and N i is the refractive index at the d-line of the i-th lens from the viewing side.

Claim 9

An ocular optical system having a wide diopter adjustment range comprising, in order from the viewing side, a first lens component having a negative refracting power, a second lens component having a positive refracting power, a third lens component having a negative refracting power, a penta prism and a condenser lens component wherein the second lens component having the positive refracting power is movable for diopter adjustment, said optical system satisfying the following conditions: ______________________________________ F = 63.235 r.sub.1 -70.000 d.sub.1 0.80 n.sub.1 1.74077 ν.sub.1 27.8 r.sub.2 116.372 d.sub.2 2.73 r.sub.3 -100.000 d.sub.3 2.27 n.sub.2 1.88300 ν.sub.2 40.8 r.sub.4 -33.300 d.sub.4 0.2 r.sub.5 47.480 d.sub.5 3.41 n.sub.3 1.80440 ν.sub.3 47.4 r.sub.6 -62.240 d.sub.6 3.75 r.sub.7 -69.147 d.sub.7 0.80 n.sub.4 1.78472 ν.sub.4 25.7 r.sub.8 82.000 d.sub.8 1.18 r.sub.9 ∞ d.sub.9 81.09 n.sub.5 1.51633 ν.sub.5 64.1 r.sub.10 ∞ d.sub.10 1.00 r.sub.11 78.000 d.sub.11 3.50 n.sub.6 1.80518 ν.sub.6 25.4 r.sub.12 ∞ d.sub.12 1.60 (1) F.sub.1 = -0.9314F (2) F.sub.1·2 = 0.4615F (3) (ν.sub.2 + ν.sub.3)/(ν.sub.1 + ν.sub.4) = 1.475 diopter d.sub.2 d.sub.6 -3.0 D 5.74 0.73 1.5 D 0.74 5.62 ______________________________________ where F is the overall focal length of the optical system, F 1 2 . . . i is the resultant focal length up to the i-th lens component, and ν i is the Abbe number of the i-th lens from the viewing side, r i is the radius of curvature of the i-th lens from the viewing side, d i is the distance between adjacent lenses or the lens thickness of the i-th lens from the viewing side, and N i is the refractive index at the d-line of the i-th lens from the viewing side.

Claim 10

An ocular optical system having a wide diopter adjustment range comprising, in order from the viewing side, a first lens component having a negative refracting power, a second lens component having a positive refracting power, a third lens component having a negative refracting power, a penta prism and a condenser lens component wherein the second lens component having the positive refracting power is movable for diopter adjustment, said optical system satisfying the following conditions: ______________________________________ F = 63.235 r.sub.1 -70.000 d.sub.1 0.80 n.sub.1 1.74077 ν.sub.1 27.8 r.sub.2 116.372 d.sub.2 2.73 r.sub.3 -100.000 d.sub.3 2.27 n.sub.2 1.88300 ν.sub.2 40.8 r.sub.4 -33.300 d.sub.4 0.2 r.sub.5 47.480 d.sub.5 3.41 n.sub.3 1.80440 ν.sub.3 47.4 r.sub.6 -62.240 d.sub.6 3.75 r.sub.7 -69.147 d.sub.7 0.80 n.sub.4 1.78472 ν.sub.4 25.7 r.sub.8 82.000 d.sub.8 1.18 r.sub.9 ∞ d.sub.9 81.09 n.sub.5 1.51633 ν.sub.5 64.1 r.sub.10 ∞ d.sub.10 1.00 r.sub.11 78.000 d.sub.11 3.50 n.sub.6 1.80518 ν.sub.6 25.4 r.sub.12 ∞ d.sub.12 1.60 (1) F.sub.1 = -0.9314F (2) F.sub.1·2 = 0.4615F (3) (ν.sub.2 + ν.sub.3)/(ν.sub.1 + ν.sub.4) = 1.475 diopter d.sub.2 d.sub.6 -3.0 D 5.74 0.73 1.5 D 0.74 5.62 ______________________________________ where F is the overall focal length of the optical system, F 1 2 . . . i is the resultant focal length up to the i-th lens component, and ν i is the Abbe number of the i-th lens from the viewing side, r i is the radius of curvature of the i-th lens from the viewing side, d i is the distance between adjacent lenses or the lens thickness of the i-th lens from the viewing side, and N i is the refractive index at the d-line of the i-th lens from the viewing side.

Claim 11

An ocular optical system having a wide diopter adjustment range comprising, in order from the viewing side, a first lens component having a negative refracting power, a second lens component having a positive refracting power, a third lens component having a negative refracting power, a penta prism and a condenser lens component wherein the second lens component having the positive refracting power is movable for diopter adjustment, said optical system satisfying the following conditions: ______________________________________ F = 63.207 r.sub.1 -80.500 d.sub.1 0.80 n.sub.1 1.80518 ν.sub.1 25.4 r.sub.2 115.895 d.sub.2 2.74 r.sub.3 -100.000 d.sub.3 2.27 n.sub.2 1.88300 ν.sub.2 40.8 r.sub.4 -33.300 d.sub.4 0.2 r.sub.5 47.480 d.sub.5 3.41 n.sub.3 1.81600 ν.sub.3 46.6 r.sub.6 -64.350 d.sub.6 3.73 r.sub.7 -69.147 d.sub.7 0.8 n.sub.4 1.80518 ν.sub.4 25.4 r.sub.8 87.000 d.sub.8 1.18 r.sub.9 ∞ d.sub.9 81.09 n.sub.5 1.51633 ν.sub.5 64.1 r.sub.10 ∞ d.sub.10 1.00 r.sub.11 78.000 d.sub.11 3.50 n.sub.6 1.80518 ν.sub.6 25.4 r.sub.12 ∞ d.sub.12 1.60 (1) F.sub.1 = -0.9317F (2) F.sub.1·2 = 0.4617F (3) (ν.sub.2 + ν.sub.3)/(ν.sub.1 + ν.sub.4) = 1.720 diopter d.sub.2 d.sub.6 -3.0 D 5.76 0.71 1.5 D 0.87 5.60 ______________________________________ where F is the overall focal length of the optical system, F 1 2 . . . i is the resultant focal length up to the i-th lens component, and ν i is the Abbe number of the i-th lens from the viewing side, r i is the radius of curvature of the i-th lens from the viewing side, d i is the distance between adjacent lenses or the lens thickness of the i-th lens from the viewing side, and N i is the refractive index at the d-line of the i-th lens from the viewing side.

Claim 12

An ocular optical system having a wide diopter adjustment range comprising, in order from the viewing side, a first lens component having a negative refracting power, a second lens component having a positive refracting power, a third lens component having a negative refracting power, a penta prism and a condenser lens component wherein the second lens component having the positive refracting power is movable for diopter adjustment, said optical system satisfying the following conditions: ______________________________________ F = 63.207 r.sub.1 -80.500 d.sub.1 0.80 n.sub.1 1.80518 ν.sub.1 25.4 r.sub.2 115.895 d.sub.2 2.74 r.sub.3 -100.000 d.sub.3 2.27 n.sub.2 1.88300 ν.sub.2 40.8 r.sub.4 -33.300 d.sub.4 0.2 r.sub.5 47.480 d.sub.5 3.41 n.sub.3 1.81600 ν.sub.3 46.6 r.sub.6 -64.350 d.sub.6 3.73 r.sub.7 -69.147 d.sub.7 0.8 n.sub.4 1.80518 ν.sub.4 25.4 r.sub.8 87.000 d.sub.8 1.18 r.sub.9 ∞ d.sub.9 81.09 n.sub.5 1.51633 ν.sub.5 64.1 r.sub.10 ∞ d.sub.10 1.00 r.sub.11 78.000 d.sub.11 3.50 n.sub.6 1.80518 ν.sub.6 25.4 r.sub.12 ∞ d.sub.12 1.60 (1) F.sub.1 = -0.9317F (2) F.sub.1·2 = 0.4617F (3) (ν.sub.2 + ν.sub.3)/(ν.sub.1 + ν.sub.4) = 1.720 diopter d.sub.2 d.sub.6 -3.0 D 5.76 0.71 1.5 D 0.87 5.60 ______________________________________ where F is the overall focal length of the optical system, F 1 2 . . . i is the resultant focal length up to the i-th lens component, and ν i is the Abbe number of the i-th lens from the viewing side, r i is the radius of curvature of the i-th lens from the viewing side, d i is the distance between adjacent lenses or the lens thickness of the i-th lens from the viewing side, and N i is the refractive index at the d-line of the i-th lens from the viewing side.