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US 3,944,338 AGranted
Short focal length long back focus objective
AssigneeBell & Howell Company
InventorAndor A. Fleischman
Life of this patent
Estimating the term…
Abstract
This invention relates to a short focal length, large aperture optical system having a relatively long back focus primarily designed to efficiently transmit monochromatic light rays to an image plane with an extraordinarily high degree of correction over a prescribed field.
Claims2
An optical system of relatively short focal length and large aperture having a relatively long back focus and substantially the following specification:
- EFL = 8.17mm(.3215 inch) 1/2 Angle of Field = 2.58.degree. LENS RADII (IN.) THICKNESS (IN.) SPACING (IN.) ______________________________________ L.sub.1 R.sub.1 = .8800 D.sub.1 = .0750 R.sub.2 = 15.4000 S.sub.1 = .0350 L.sub.2 R.sub.3 = -.3370 D.sub.2 = .2230 R.sub.4 = .4120 S.sub.2 = .3100 L.sub.3 R.sub.5 = .4310 D.sub.3 = .0960 R.sub.6 = -6.6720 S.sub.3 = .0040 L.sub.4 R.sub.7 = .1750 D.sub.4 = .0940 R.sub.8 = -.2450 S.sub.4 = .1000 (.1545 BFL) L.sub.5 R.sub.9 = Inf. D.sub.5 = .0492 R.sub.10 = Inf. 0 .ltoreq. S.sub.5 .ltoreq. .0053 For ELEMENTS L.sub.1, L.sub.3 V = 25.4 N.sub.D = 1.805 For ELEMENTS L.sub.2, L.sub.4 V = 66.1 N.sub.D = 1.494 ELEMENT L.sub.5 -- OPTICAL MATERIAL ______________________________________
- wherein the first column lists the lens elements numerically starting at the ray entrance side of the system which elements each have the dispersive index V and the refractive index N.sub.D ;
- the second column lists the respective base radii R.sub.1 to R.sub.10 ;
- the third column lists the thickness D.sub.1 to D.sub.5 of the respective elements;
- and the fourth column lists the axial spacings S.sub.1 to S.sub.5 between the respective elements, and the image plane.
2 more elements
An optical system of relatively short focal length and large aperture having a relatively long back focus and substantially the following specification:
- EFL = 8.17mm 1/2 Angle of Field = 2.58.degree. LENS RADII (IN.) THICKNESS (IN.) SPACING (IN.) ______________________________________ L.sub.1 R.sub.1 = .8800 D.sub.1 = .0810 R.sub.2 = 15.4000 S.sub.1 = .350 L.sub.2 R.sub.3 = -.3370 D.sub.2 = .2250 R.sub.4 = .4120 S.sub.2 = .3110 L.sub.3 R.sub.5 = .4310 D.sub.3 = .0880 R.sub.6 = -6.6720 S.sub.3 = .0040 L.sub.4 R.sub.7 = .1715 D.sub.4 = .0970 R.sub.8 = -.2450 S.sub.4 = .1000 (.1535 BFL) L.sub.5 R.sub.9 = Inf. D.sub.5 = .0492 R.sub.10 = Inf. 0 .ltoreq. S.sub.5 .ltoreq. .1044 For ELEMENTS L.sub.1, L.sub.3 V = 25.4 N.sub.D = 1.805 For ELEMENTS L.sub.2, L.sub.4 V = 57.4 N.sub.D = 1.490 ELEMENT L.sub.5 -- OPTICAL MATERIAL ______________________________________
- wherein the first column lists the lens elements numerically starting at the ray entrance side of the system which elements each have the dispersive index V and the refractive index N.sub.D ;
- the second column lists the respective base radii R.sub.1 to R.sub.10 ;
- the third column lists the thickness D.sub.1 to D.sub.5 of the respective elements;
- and the fourth column lists the axial spacings S.sub.1 to S.sub.5 between the respective elements, and the image plane.
2 more elements
Dependencies are inferred from the claim text.