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| Number | Title | Issue Date |
| 4636040 | Zoom lens system A zoom lens system with a focusing system other than a front group focusing system is provided. The lens system comprises a first lens group including at least two subgroups with a variable air space therebetween to be varied during zooming, and a focusin... | 01/13/1987 |
| 4571031 | Wide angle zoom objective A wide angle zoom objective has three lens units of which the first counting from front is of negative power, the second is of positive power and the third is of negative power. At least one lens surface in the first unit has an aspheric surface, and the ... | 02/18/1986 |
| 4509833 | High variable magnification wide angle zoom lens A wide angle zoom lens with an increased varifocal range comprises, from front to rear, a divergent 1st lens group, a convergent 2nd lens group and a divergent 3rd lens group, the aforesaid three lens groups being axially movable to effect zooming, and th... | 04/09/1985 |
| 4411488 | Afocal zoom refractor telescopes An afocal zoom refractor telescope 20 is formed by a variable magnification achromatic objective system 18 and a fixed focus eyepiece system 19 aligned on a common optical axis 17 and arranged to provide an internal real image I. The objective system 18 i... | 10/25/1983 |
| 4304466 | Zoom lens An improved optical system for a relatively compact zoom lens of relatively high speed, moderate range, and extending from normal into the telephoto region, the lens being of simple construction and having two lens groups and as few as six elements.... | 12/08/1981 |
| 4303311 | Short distance zoom lens system A short distance zoom lens system for forming an image of an object lying at any short distance at a predetermined short distance comprises, in order from the object side, a first group which is a divergent lens group, a second group which is a convergent... | 12/01/1981 |
| 4198127 | Wide angle zoom lens system having small distortion The present invention provides a compact zoom lens which exhibits small distortion aberration. The lens system comprises, in order from the object side, a front lens group having a negative focal length and a rear lens group having a positive focal length... | 04/15/1980 |
| 4196969 | Zoom lens having a small distortion aberration The present invention provides a compact zoom lens which exhibits only small distortion aberration. The present invention comprises, in order from the object side, a first lens group having a negative focal length, a second lens group having a positive fo... | 04/08/1980 |
| 4170402 | Very compact wide-angle zoom lens system A very compact wide-angle zoom lens system with favorably corrected aberrations comprising a first lens group consisting of a negative meniscus lens element and a lens component having negative refractive power, a second lens group consisting of a positiv... | 10/09/1979 |
| 4018510 | Varifocal objective containing movable lens component of positive refractivity An objective of variable focal length affording an aperture ratio of about 1:1.0 to 1:1.4 for narrow film projectors and microscopes comprising at least six lens members separated by air spaces, characterized by the following construction and arrangement ... | 04/19/1977 |
| 3994572 | Varifocal lens system with macro-photography capabilities A macro-photography varifocal lens assembly is provided for attachment to a camera body. The lens assembly can include a first lens group of negative refractive power and a second lens group of positive refractive power further supplemented by a master or... | 11/30/1976 |
| 3942874 | Pancratic wide-angle objective A pancratic wide-angle objective comprises a stationary negative front component in the form of a single meniscus with a convex forward surface, an axially movable intermediate component consisting of a biconvex lens, and a stationary multilens positive r... | 03/09/1976 |
