Abbe condenser

Claim 2

A two-component microscope condenser having a working distance effective for either an air space or oil filled space and having a front pupil plane external to the glass thereof, said condenser consisting of a biconvex positive doublet and a convex-plano positive doublet aligned along an optical axis.

Claim 3

The condenser of claim 1 wherein said biconvex doublet has an aspherical first surface.

Claim 4

The condenser of claim 2 in which said two components have parameters of lens radii (R), a minus sign (-) indicates center of curvature on the pupil side of the lens, thicknesses (T), spacings (S), indices of refraction (ND) and Abbe numbers (ν) as follows: __________________________________________________________________________ Index of Abbe Lens Radius Thickness Spacing Refraction Number __________________________________________________________________________ S.sub.10 =0.2894X R.sub.11 = 1.2120X T.sub.11 =1.0311X 1.522<ND.sub.11 <1.524 γ.sub.11 ≅58 I R.sub.12 =-1.4414X T.sub.12 =0.1905X 1.785<ND.sub.12 <1.787 γ.sub.12 ≅25 R.sub.13 =-3.3477X S.sub.11 =0.0095X R.sub.14 = 0.7720X T.sub.13 =0.4264X 1.619<ND.sub.13 <1.621 γ.sub.13 ≅60 II R.sub.15 =∞ T.sub.14 =0.5212X 1.785<ND.sub.14 <1.787 γ.sub.14 ≅25 R.sub.16 =∞ S.sub.12 =0.0381X __________________________________________________________________________ wherein X is 9 to 13mm, the surface having radius R 11 is an axially symmetrical aspherical surface conforming to the equation ##EQU3## with a conic coefficient (k) of -0.536389 and deformation coefficients d of 0.380331·10 -5 , e of -0.428527·10 -7 , f of 0.124135·10 -8 and g of -0.709653·10 -11 .

Claim 5

The condenser of claim 3 wherein X is 10.5mm, ND 11 is 1.523, ND 12 is 1.786, ND 13 is 1.620, ND 14 is 1.786, ν 11 is 58.6, ν 12 is 25.5, ν 13 is 60.3 and ν 14 is 25.5.

Claim 6

The condenser of claim 1 in which said two components have parameters of lens radii (R), a minus sign (-) indicates center of curvature on the pupil side of the lens, thicknesses (T), spacings (S), indicates of refraction (ND) and Abbe numbers (ν) as follows: __________________________________________________________________________ Index of Abbe Lens Radius Thickness Spacing Refraction Number __________________________________________________________________________ S.sub.0 =0.3562X R.sub.1 = 1.9558X T.sub.1 =0.9662X 1.620<ND.sub.(1) <1.621 γ.sub.(1) ≅60 I R.sub.2 =-1.2632X T.sub.2 =0.1905X 1.78<ND.sub.(2) <1.79 γ.sub.(2) ≅25 R.sub.3 =-4.3594X S.sub.1 =0.0095X R.sub.4 = 0.8097X T.sub.3 =0.7669X 1.66<ND.sub.(3) <1.67 γ.sub.(3) ≅42 II R.sub.5 = ∞ T.sub.4 =0.3900X 1.78<ND.sub.(4) <1.79 γ.sub.(4) ≅25 R.sub.6 =∞ S.sub.2 =0.0286X __________________________________________________________________________ wherein X is 9 to 13mm.

Claim 7

The condenser of claim 5 wherein X is 10.5, ND 1 is 1.6203, ND 2 is 1.78600, ND 3 is 1.66741, ND 4 is 1.78600, ν 1 is 60.3, ν 2 is 25.5, ν 3 is 41.9 and ν 4 is 25.5.

Claim 8

The condenser of claim 2 in which said two components have parameters of lens radii (R), a minus sign (-) indicates center of curvature and the pupil side of the lens, thicknesses (T), spacings (S), indies of refraction (ND) and Abbe numbers (ν) as follows: __________________________________________________________________________ Index of Abbe Lens Radius Thickness Spacing Refraction Number __________________________________________________________________________ S.sub.10 =0.163X R.sub.11 = 1.261X 1.5<ND.sub.11 <1.6 γ.sub.11 ≅59 T.sub.11 =1.085X XI R.sub.12 =-1.385X T.sub.12 =0.271X 1.7<ND.sub.12 <1.8 γ.sub.12 ≅25 R.sub.13 =-2.891X S.sub.11 =0.009X R.sub.14 = 0.719X T.sub.13 =0.414X 1.5<ND.sub.13 <1.6 γ.sub.13 ≅61 XII R.sub.15 =∞ T.sub.14 =0.5423X 1.7<ND.sub.14 <1.8 γ.sub.14 ≅25 R.sub.16 =∞ S.sub.12 =0.036X __________________________________________________________________________ wherein X is 9 to 13mm, the surface having radius R 11 is an axially symmetrical aspheric surface conforming to the equation ##EQU4## with a conic coefficient (k) of -0.556707, and deformation coefficients d of 0.335486·10 -5 , e of -0.329104·10 -7 , f of 0.70309·10 -9 and g of -0.349273·10 -11 .

Claim 9

The condenser of claim 7 wherein X is 11.4mm, ND 11 is 1.523, ND 12 is 1.786, ND 13 is 1.589, ND 14 is 1.786, ν 11 is 58.6, ν 12 is 25.5, ν 13 is 61.2 and ν 14 is 25.5.

Claim 10

The condenser of claim 2 further including a negative lens having a concave rear surface positioned near the front pupil plane of said condenser.

Claim 11

The condenser of claim 9 wherein said negative lens has a focal length of about -32.9 to about -89.6.

Claim 12

The condenser of claim 8 further including a plano-concave negative lens to provide an air working distance, S 22 , of 2.5 to 5mm.

Claim 13

The condenser of claim 11 wherein said negative lens has a concave radius, R 22 , of 39.779mm, a thickness, T 21 , of 3.60mm, an index of refraction, ND 21 , of 1.689, an Abbe number, ν 21 , of 30.9 and the working distance is about 3.3mm.