Abstract: A high power objective or lens system of the same general kind as disclosed in Glatzel U.S. Pat. No. 3,915,558, but with a larger aperture and a slightly smaller angular field of view. Rules or conditions are disclosed which, if complied with, will result in a lens with improved image formation. The present lens is particularly suitable for cinematographic purposes.

Abstract: An extremely high speed wide angle objective lens system, wherein a reducing Newtonian finder telescope is arranged in front of an objective lens group which produces a real image on an image plane. Rules or conditions are stated, and several specific examples are given. In many of the examples, the back focus distance is relatively large, thus making the lens system suitable for use with a mirror reflex camera where room is needed for swinging the reflex mirror.

Abstract: A wide angle lens of moderate aperture, similar in general to the lens of Glatzel et al. U.S. Pat. No. 3,833,290, but differing from it and from other similar lenses in the refractive power distribution as between two dispersing components near the front of the lens, and the refractive power distribution as between two air lenses, one formed between the two dispersive components just mentioned and the other formed between the second dispersing component and a next following condensing component. By designing the lens to have the power distribution at these points between certain stated limits, greatly increased performance is achieved, with reduction of specific aberrations of higher order, and with sharpness of distant real points brought extremely close to the ideal Rayleigh limit.

Abstract: An objective of the expanded Tessar type, having five elements constituting four components (two of the elements being cemented to each other to form one component), all of the components being air spaced from each other. The front two components (in the direction from the object or long conjugate side toward the image or short conjugate side) are both positive. Numerical limits or ranges are given, for certain designated features of the lens system. If a lens of this type is so designed that the designated features fall within the specified ranges, improved results are attained.