Endoscope with resistance heater
A medical endoscope and insertion portion for a medical endoscope having a fiber tube that encloses an image guide and is surrounded by optical fibers, the distal opening of said fiber tube being sealed by a window, which is heated by an electric resistance heater located close by, wherein the heater is designed as heating foil arranged on the outer surface of the fiber tube.
1. A medical endoscope comprising:
an outer tube;
an image guide;
a fiber tube that encloses the image guide;
optical fibers disposed within the outer tube and outside of the fiber tube;
a window disposed at a distal opening of the fiber tube; and
an electric resistance heater for heating the window, wherein the electric resistance heater is a heating foil arranged proximate to the window on an outer surface of the fiber tube.
2. The endoscope according to claim 1 , wherein a distal edge of the heating foil is located offset from a front face of the endoscope.
3. The endoscope according to claim 2 , wherein a space between the front face of the endoscope and the distal edge of the heating foil is filled with a potting material.
4. The endoscope according to claim 1 , wherein the fiber tube is metallic.
5. The endoscope according to claim 4 , wherein a distal portion of the fiber tube contacts the window so as to conduct heat from the heating foil to the window via the fiber tube.
6. An insertion portion for a medical endoscope, the insertion portion comprising:
an outer tube;
an image guide;
a fiber tube that encloses the image guide;
optical fibers disposed within the outer tube and outside of the fiber tube;
a window disposed at a distal opening of the fiber tube; and
an electric resistance heater for heating the window, wherein the electric resistance heater is a heating foil arranged proximate to the window on an outer surface of the fiber tube.
7. The insertion portion according to claim 6 , wherein a distal edge of the heating foil is located offset from a front face of the endoscope.
8. The insertion portion according to claim 7 , wherein a space between the front face of the endoscope and the distal edge of the heating foil is filled with a potting material.
9. The insertion portion according to claim 6 , wherein the fiber tube is metallic.
10. The insertion portion according to claim 9 , wherein a distal portion of the fiber tube contacts the window so as to conduct heat from the heating foil to the window via the fiber tube.