Objective lens system for microscopes

Claim 2

An objective lens system for microscopes comprising a front lens group consisting of a first positive meniscus lens component and a second positive cemented doublet component, and a rear lens group consisting of a third lens component having positive refractive power and a fourth lens component having positive refractive power, and said lens system satisfying the following conditions: 0.5<r.sub.1 /r.sub.2 <0.8 (1) 0.3<r.sub.5 /R<1.1 (2) 0.12f<d.sub.1 /n.sub.1 <0.19f (3) 30<[(ν.sub.2 -ν.sub.3)+(ν.sub.p -ν.sub.n)]<120 (4) 0.35<f.sub.1 /f.sub.2 <0.65 (5) wherein the reference symbols r 1 and r 2 represents radii of curvature on both the surfaces of the first lens component, the reference symbol r 5 designates radius of curvature on the image side surface of the second lens component, the reference symbol R denotes radius of curvature on the image side surface of the third lens component, the reference symbol d 1 represents thickness of the first lens component, the reference symbol n 1 designates refractive index of the first lens component, the reference symbols ν 2 and ν 3 denote Abbe's numbers of both the elements respectively of the second lens component, the reference symbol ν p and ν n represent Abbe's numbers of the positive and negative lens elements respectively of the cemented doublet component arranged in the rear lens group, and the reference symbols f 1 and f 2 designate focal lengths of the front and rear lens groups respectively.

Claim 3

An objective lens system for microscopes according to claim 1 satisfying the following additional condition (6): ##EQU4## wherein the reference symbols N n and N p represent refractive indices of the negative and positive lens elements respectively of said cemented doublet component arranged in said rear lens group and the reference symbol R' designates radius of curvature on the cemented surface of said cemented doublet component arranged in said rear lens group.

Claim 4

An objective lens system for microscopes according to claim 2 wherein said third lens component is a single-element lens component and said fourth lens component is a positive cemented doublet component.

Claim 5

An objective lens system for microscope according to claim 3 so adapted as to satisfy the following conditions (2'), (4') and (6'): 0.3<r.sub.5 /R<0.5 (2') 70<[(ν.sub.3 -ν.sub.2)+(ν.sub.p -ν.sub.n)]<120 (4') 0.13<|(N.sub.n -N.sub.p)/R'|f<0.25 (6').

Claim 6

An objective lens system for microscopes according to claim 4 having the following numerical data: ______________________________________ r.sub.1 = -0.2293 d.sub.1 = 0.2399 n.sub.1 = 1.61659 ν.sub.1 = 36.63 r.sub.2 = -0.3664 d.sub.2 = 0.0051 r.sub.3 = 4.3251 d.sub.3 = 0.0436 n.sub.2 = 1.57957 ν.sub.2 = 53.75 r.sub.4 = 0.5891 d.sub.4 = 0.1894 n.sub.3 = 1.43389 ν.sub.3 = 95.15 r.sub.5 = -0.4488 d.sub.5 = 1.2629 r.sub.6 = -3.6847 d.sub.6 = 0.1768 n.sub.4 = 1.48749 ν.sub.4 = 70.15 r.sub.7 = -1.0139 d.sub.7 = 0.0316 r.sub.8 = 2.3172 d.sub.8 = 0.1086 n.sub.5 = 1.61659 ν.sub.5 = 36.63 r.sub.9 = 0.8443 d.sub.9 = 0.1894 n.sub.6 = 1.143389 ν.sub.6 = 95.15 r.sub.10 = -4.5056 f = 1 NA = 0.4 β = -10X f.sub.1 = 1.08 f.sub.2 = 1.99 ______________________________________ wherein the reference symbols r 1 through r 10 represent radii of curvature on the surfaces of the respective lens elements, the reference symbols d 1 through d 9 designate thicknesses of the respective lens elements and airspace reserved therebetween, the reference symbols n 1 through n 5 denote refractive indices of the respective lens elements, the reference symbols ν 1 through ν 5 represent Abbe's numbers of the respective lens elements, the reference symbol NA designates numerical aperture and the reference symbol β denotes magnification.

Claim 7

An objective lens system for microscopes according to claim 4 having the following numerical data: ______________________________________ r.sub.1 = -0.2459 d.sub.1 = 0.2396 n.sub.1 = 1.61659 ν.sub.1 = 36.63 r.sub.2 = -0.3818 d.sub.2 = 0.0050 r.sub.3 = 4.4832 d.sub.3 = 0.0435 n.sub.2 = 1.57957 ν.sub.2 = 53.75 r.sub.4 = 0.5852 d.sub.4 = 0.2144 n.sub.3 = 1.43389 ν.sub.3 = 95.15 r.sub.5 = -0.4491 d.sub.5 = 1.2610 r.sub.6 = -4.9133 d.sub.6 = 0.1765 n.sub.4 = 1.48749 ν.sub.4 = 70.15 r.sub.7 = -1.0536 d.sub.7 = 0.0315 r.sub.8 = 2.2089 d.sub.8 = 0.1084 n.sub.5 = 1.61659 ν.sub.5 = 36.63 r.sub.9 = 0.8289 d.sub.9 = 0.1892 n.sub.6 = 1.43389 ν.sub.6 = 95.15 r.sub.10 = -6.2556 f = 1 NA = 0.4 β = -10X f.sub.1 = 1.07 f.sub.2 = 2.00 ______________________________________ wherein the reference symbols r 1 through r 10 represent radii of curvature on the surfaces of the respective lens elements, the reference symbols d 1 through d 9 designate thicknesses of the respective lens elements and airspace reserved therebetween, the reference symbols n 1 through n 5 denote refractive indices of the respective lens elements, the reference symbols ν 1 through ν 5 represent Abbe's numbers of the respective lens elements, the reference symbol NA designates numerical aperture and the reference symbol β denotes magnification.

Claim 8

An objective lens system for microscopes according to claim 4 having the following numerical data: ______________________________________ r.sub.1 = -0.2168 d.sub.1 = 0.2333 n.sub.1 = 1.61659 ν.sub.1 = 36.63 r.sub.2 = -0.3313 d.sub.2 = 0.0048 r.sub.3 = 5.2569 d.sub.3 = 0.0418 n.sub.2 = 1.57957 ν.sub.2 = 53.75 r.sub.4 = 0.5343 d.sub.4 = 0.1818 n.sub.3 = 1.43389 ν.sub.3 = 95.15 r.sub.5 = -0.3793 d.sub.5 = 1.5147 r.sub.6 = -49.8194 d.sub.6 = 0.1696 n.sub.4 = 1.48749 ν.sub.4 = 70.15 r.sub.7 = -1.1560 d.sub.7 = 0.0303 r.sub.8 = 2.5250 d.sub.8 = 0.1042 n.sub.5 = 1.61659 ν.sub.5 = 36.63 r.sub.9 = 0.7026 d.sub.9 = 0.1818 n.sub.6 = 1.48749 ν.sub.6 = 70.15 r.sub.10 = 25.0452 f = 1 NA = 0.4 β = -10X f.sub.1 = 0.811 f.sub.2 = 2.16 ______________________________________ wherein the reference symbols r 1 through r 10 represent radii of curvature on the surfaces of the respective lens elements, the reference symbols d 1 through d 9 designate thicknesses of the respective lens elements and airspace reserved therebetween, the reference symbols n 1 through n 5 denote refractive indices of the respective lens elements, the reference symbols ν 1 through ν 5 represent Abbe's numbers of the respective lens elements, the reference symbol NA designates numerical aperture and the reference symbol β denotes magnification.

Claim 9

An objective lens system for microscopes according to claim 4 having the following numerical data: ______________________________________ r.sub.1 = -0.2095 d.sub.1 = 0.2372 n.sub.1 = 1.61659 ν.sub.1 = 36.63 r.sub.2 = -0.3158 d.sub.2 = 0.0050 r.sub.3 = 5.0101 d.sub.3 = 0.0431 n.sub.2 = 1.61659 ν.sub.2 = 36.63 r.sub.4 = 0.7297 d.sub.4 = 0.2122 n.sub.3 = 1.43389 ν.sub.3 = 95.15 r.sub.5 = -0.4680 d.sub.5 = 1.2482 r.sub.6 = -3.3554 d.sub.6 = 0.1747 n.sub.4 = 1.48749 ν.sub.4 = 70.15 r.sub.7 = -1.1513 d.sub.7 = 0.0312 r.sub.8 = 7.9857 d.sub.8 = 0.1073 n.sub.5 = 1.58921 ν.sub.5 = 41.08 r.sub.9 = 1.0061 d.sub.9 = 0.1872 n.sub.6 = 1.43389 ν.sub.6 = 95.15 r.sub.10 = -1.5490 f = 1 NA = 0.4 β = -10X f.sub.1 = 0.96 f.sub.2 = 2.10 ______________________________________ wherein the reference symbols r 1 through r 10 represent radii of curvature on the surfaces of the respective lens elements, the reference symbols d 1 through d 9 designate thicknesses of the respective lens elements and airspace reserved therebetween, the reference symbols n 1 through n 5 denote refractive indices of the respective lens elements, the reference symbols ν 1 through ν 5 represent Abbe's numbers of the respective lens elements, the reference symbol NA designates numerical aperture and the reference symbol β denotes magnification.

Claim 10

An objective lens system for microscopes according to claim 2 wherein said third lens component is a positive cemented doublet component and said fourth lens component is a positive single-element lens component.

Claim 11

An objective lens system according to claim 9 so adapted as to satisfy the following conditions (2"), (4") and (6"): 0.4<r.sub.5 /R<1.1 (2") 30<[(ν.sub.3 -ν.sub.2)+(ν.sub.p -ν.sub.n)]<70 (4") 0.075<|(N.sub.n -N.sub.p)/R'|f<0.13 (6").

Claim 12

An objective lens system for microscopes according to claim 10 having the following numerical data: ______________________________________ r.sub.1 = -0.2065 d.sub.1 = 0.2551 n.sub.1 = 1.61659 ν.sub.1 = 36.63 r.sub.2 = -0.3465 d.sub.2 = 0.0050 r.sub.3 = -5.6243 d.sub.3 = 0.0429 n.sub.2 = 1.61659 ν.sub.2 = 36.63 r.sub.4 = 0.3834 d.sub.4 = 0.2115 n.sub.3 = 1.61117 ν.sub.3 = 55.92 r.sub.5 = -0.5668 d.sub.5 = 1.2442 r.sub.6 = -2.1238 d.sub.6 = 0.1070 n.sub.4 = 1.61659 ν.sub.4 = 36.63 r.sub.7 = 1.4540 d.sub.7 = 0.1860 n.sub.5 = 1.48749 ν.sub.5 = 70.15 r.sub.8 = -1.0154 d.sub.8 = 0.0305 r.sub.9 = 4.9207 d.sub.9 = 0.1742 n.sub.6 = 1.48749 ν.sub.6 = 70.15 r.sub.10 = -2.2830 f = 1 NA = 0.4 β = -10X f.sub.1 = 0.884 f.sub.2 = 2.18 ______________________________________ wherein the reference symbols r 1 through r 10 represent radii of curvature on the surfaces of the respective lens elements, the reference symbols d 1 through d 9 designate thicknesses of the respective lens elements and airspace reserved therebetween, the reference symbols n 1 through n 5 denote refractive indices of the respective lens elements, the reference symbols ν 1 through ν 5 represent Abbe's numbers of the respective lens elements, the reference symbol NA designates numerical aperture and the reference symbol β denotes magnification.

Claim 13

An objective lens system for microscopes according to claim 10 having the following numerical data: ______________________________________ r.sub.1 = -0.2179 d.sub.1 = 0.2515 n.sub.1 = 1.51633 ν.sub.1 = 64.15 r.sub.2 = -0.3026 d.sub.2 = 0.0062 r.sub.3 = 3.1358 d.sub.3 = 0.0418 n.sub.2 = 1.71700 ν.sub.2 = 47.94 r.sub.4 = 0.8726 d.sub.4 = 0.1107 n.sub.3 = 1.61720 ν.sub.3 = 54.04 r.sub.5 = -0.9623 d.sub.5 = 1.1266 r.sub.6 = -3.3947 d.sub.6 = 0.1052 n.sub.4 = 1.64769 ν.sub.4 = 33.80 r.sub.7 = 1.5258 d.sub.7 = 0.1365 n.sub.5 = 1.49831 ν.sub.5 = 65.03 r.sub.8 = -0.9225 d.sub.8 = 0.0307 r.sub.9 = 3.6194 d.sub.9 = 0.2460 n.sub.6 = 1.58528 ν.sub.6 = 50.87 r.sub.10 = -4.4582 f = 1 NA = 0.4 β = -10X f.sub.1 = 0.95 f.sub.2 = 1.77 ______________________________________ wherein the reference symbols r 1 through r 10 represent radii of curvature on the surfaces of the respective lens elements, the reference symbols d 1 through d 9 designate thicknesses of the respective lens elements and airspace reserved therebetween, the reference symbols n 1 through n 5 denote refractive indices of the respective lens elements, the reference symbols ν 1 through ν 5 represent Abbe's numbers of the respective lens elements, the reference symbol NA designates numerical aperture and the reference symbol β denotes magnification.

Claim 14

An objective lens system for microscopes according to claim 10 having the following numerical data: ______________________________________ r.sub.1 = -0.2689 d.sub.1 = 0.2473 n.sub.1 = 1.61659 ν.sub.1 = 36.63 r.sub.2 = -0.4551 d.sub.2 = 0.0060 r.sub.3 = 3.2970 d.sub.3 = 0.0423 n.sub.2 = 1.61659 ν.sub.2 = 36.63 r.sub.4 = 0.5488 d.sub.4 = 0.1149 n.sub.3 = 1.55963 ν.sub.3 = 61.14 r.sub.5 = -0.5173 d.sub.5 = 1.1075 r.sub.6 = -2.4841 d.sub.6 = 0.1034 n.sub.4 = 1.61659 ν.sub.4 = 36.63 r.sub.7 = 1.2691 d.sub.7 = 0.1632 n.sub.5 = 1.48749 ν.sub.5 = 70.15 r.sub.8 = -1.0786 d.sub.8 = 0.0302 r.sub.9 = 2.8706 d.sub.9 = 0.1693 n.sub.6 = 1.51728 ν.sub.6 = 69.56 r.sub.10 = -2.2526 f = 1 NA = 0.4 β = -10X f.sub.1 = 0.88 f.sub.2 = 1.84 ______________________________________ wherein the reference symbols r 1 through r 10 represent radii of curvature on the surfaces of the respective lens elements, the reference symbols d 1 through d 9 designate thicknesses of the respective lens elements and airspace reserved therebetween, the reference symbols n 1 through n 5 denote refractive indices of the respective lens elements, the reference symbols ν 1 through ν 5 represent Abbe's numbers of the respective lens elements, the reference symbol NA designates numerical aperture and the reference symbol β denotes magnification.

Claim 15

An objective lens system for microscopes according to claim 10 having the following numerical data: ______________________________________ r.sub.1 = -0.1962 d.sub.1 = 0.2510 n.sub.1 = 1.56873 ν.sub.1 = 63.16 r.sub.2 = -0.3065 d.sub.2 = 0.0061 r.sub.3 = 1.8758 d.sub.3 = 0.0417 n.sub.2 = 1.71700 ν.sub.2 = 47.94 r.sub.4 = 0.6175 d.sub.4 = 0.1105 n.sub.3 = 1.61342 ν.sub.3 = 57.41 r.sub.5 = -0.9062 d.sub.5 = 1.1243 r.sub.6 = -2.4746 d.sub.6 = 0.1049 n.sub.4 = 1.64769 ν.sub.4 = 33.80 r.sub.7 = 1.3788 d.sub.7 = 0.1362 n.sub.5 = 1.48749 ν.sub.5 = 70.15 r.sub.8 = -1.1274 d.sub.8 = 0.0307 r.sub.9 = 5.4990 d.sub.9 = 0.2455 n.sub.6 = 1.51728 ν.sub.6 = 69.56 r.sub.10 = -1.4729 f = 1 NA = 0.4 β = -10X f.sub.1 = 0.90 f.sub.2 = 1.88 ______________________________________ wherein the reference symbols r 1 through r 10 represent radii of curvature on the surfaces of the respective lens elements, the reference symbols d 1 through d 9 designate thicknesses of the respective lens elements and airspace reserved therebetween, the reference symbols n 1 through n 5 denote refractive indices of the respective lens elements, the reference symbols ν 1 through ν 5 represent Abbe's numbers of the respective lens elements, the reference symbol NA designates numerical aperture and the reference symbol denotes magnification.