GB1019646A - Photographic objective of the modified gauss type, consisting of six lens elements - Google Patents

Abstract

1,019,646. Photographic objectives. CARL ZEISS-STIFTUNG, [trading as CARL ZEISS]. Nov. 8, 1963 [Nov. 24,1962], No. 44273/63. Heading G2J. A photographic objective of the modified Gauss type having a focal length f consists of six elements in which (1) the distance between the first vertex and the rear focal plane is less than 1. 30 f (2) L I is a collective meniscus concave to the diaphragm (3) L II is a collective meniscus concave to the diaphragm (4) L III is an unsymmetrical collective lens element turning the surface of stronger curvature r 5 towards L II (5) L IV is an unsymmetrical dispersive lens element turning the surface of stronger curvature r 7 towards the diaphragm (6) the diaphragm is between L IV and L V (7) L V is a dispersive meniscus concave to the diaphragm (8) L VI is an unsymmetrical collective lens element with the surface of stronger curvature r 11 towards the image (9) 0.4 f < r 1 < 1.2 f (10) 0.6 f < r 2 < 6.0 f (11) 0.80 < r 1 /r 3 <1.33 (12) 0.28 f <r 5 <0.45 f (13) 0.35 f < d 5 + d 6 + d 7 + d 8 < 0.65 f (14) 1. 3 (d 8 + d 9 + d 10 ) <d 1 + d 2 + d 3 + d 4 + d 5 + d 6 < 2.3(d 8 + d 9 + d 10 ) (15) all surfaces with a radius of curvature which is absolutely smaller than f have a concave curvature towards the diaphragm where #n/r is the refractive power of the corresponding surface. As shown L III and L IV are cemented together to form a dispersive meniscus component. Optical data are provided for three examples.