An endoscope has a head and an outer tube joined to it. Received in the outer tube is an inner tube in which optical components are received. Light guides are guided in the interstice between the interior space and outer tube. A closure element made of transparent material, which closes off the distal end of the outer tube in hermetically sealed fashion, is provided. The closure element has a window in the region of the inner tube. The window is surrounded by an opaque layer that shields the window radially from the entry of illumination light.