Optics tube for an endoscope, endoscope, and method for mounting at least one rod lens in an optics tube

1. An endoscope, comprising:

an optics tube;

a lens arrangement having a rod lens received in an inside of the optics tube; and

a sleeve fixed on the rod lens and at least partially enclosing the rod lens;

wherein at least an axial section of the sleeve that extends circumferentially about the rod lens is welded to the optics tube.

2. The endoscope of claim 1 , wherein the optics tube and the sleeve are made of a metallic material.

3. The endoscope of claim 1 , wherein the sleeve is adhesively bonded to the rod lens.

4. The endoscope of claim 1 , wherein the sleeve encloses the rod lens along a guide length is smaller than a length of the rod lens and which amounts to at most one third of the length of the rod lens.

5. The endoscope of claim 4 , wherein the sleeve is fixed centrally on the rod lens.

6. The endoscope of claim 1 , wherein the rod lens is a first rod lens and the lens arrangement includes a second rod lens which is adjacent to the first rod lens, and the sleeve encloses mutually facing end portions of the first and second rod lenses and is fixed thereon.

7. The endoscope of claim 6 , wherein an annular aperture stop is arranged between the first and second rod lenses.

8. The endoscope of claim 1 , wherein the sleeve has a ferromagnetic material.

9. An endoscope, comprising:

an optics tube including a lens arrangement having a rod lens received in an inside of the optics tube; and

a sleeve fixed on the rod lens and at least partially enclosing the rod lens;

wherein at least an axial section of the sleeve that extends circumferentially about the rod lens is welded to the optics tube.

10. A method for mounting a rod lens in an inside of an optics tube, the method comprising:

fixing a sleeve on the rod lens;

pushing the rod lens with the sleeve into the optics tube; and

welding to the optics tube at an axial section of the sleeve that extends circumferentially about the rod lens.

11. The method of claim 10 , wherein the sleeve has a ferromagnetic material; and

wherein the method further comprises positioning the sleeve at a predefined position inside the optics tube under an effect of a magnetic force; and

welding the sleeve to the optics tube in the predefined position.

12. The method of claim 11 , further comprising moving the sleeve in an axial direction with a gauge in order to reach an axial position, in so doing holding the sleeve magnetically against a front face of the gauge; and

welding the sleeve to the optics tube in the axial position reached.

13. The method of claim 11 , further comprising pressing the sleeve in one direction onto an inside face of the optics tube by a laterally acting magnetic force; and

welding the sleeve to the optics tube in this position.

14. The method of claim 10 , further comprising placing the optics tube in a V-shaped groove of an assembly device and, using a laterally acting force, deforming the optics tube in such a way that the sleeve bears at one or more circumferentially distributed contact lines on an inside face of the optics tube; and

welding the sleeve to the optics tube in an area of at least one of the contact lines.