The invention relates to an image transmission system for endoscopes and similar viewing tubes with at least one rod lens and at least one additional lens system. In order to produce an image transmission system of simple and economical construction, it is proposed in accordance with the invention that the minimum of one rod lens should be constructed as a plano-convex lens whose length corresponds to the curvature radius of its convex terminal surface. In addition, the invention relates to a process for producing a rod lens for an image transmission system as well as an endoscope equipped with such an image transmission system.
The present application is a continuation of pending International Patent Application PCT/EP00/01980 filed on Mar. 7, 2000, which designates the United States, and which claims priority of German patent application 199 10 050.0 filed on Mar. 8, 1999.
A relay set (4, 4') for the optical system of a rigid endoscope, the optical system including an objective (1) at the distal end, an ocular (5) at the proximal end and between them a relay lens system consisting of several relay sets (2, 3, 4), the relay set (4, 4') consisting of two half sets (4.1, 4.2) having the same lens units (11.1, 12.1, 13.1; 11.2, 12.2 13.2) arranged symmetrically with respect to the center (10) of the set (4, 4'), each half set (4.1, 4.2) consisting of two positive power lens units (11.1, 13.1; 11.2, 13.2) at the ends and one negative power lens unit (12.1; 12.2) in the middle, is characterized in that each half set is of Triplet design.
An endoscope has an endoscope tube and a lens system arranged in the endoscope tube. The lens system has endoscope lens components and air gaps between the lens components. An illumination system is arranged within the endoscope tube. The endoscope lens components each have an axial lens length; the endoscope lens components include first lens components and second lens components, wherein the axial lens length of the first lens components is the shortest axial lens length, respectively, and wherein the axial lens length of the second lens components is longer than the shortest axial lens length. The first lens components with the shortest axial lens length are arranged in an area of an axial center of the endoscope tube. The second lens components having the longer axial lens length have a first half and a second half and an air gap arranged between the first and second halves.
