Endoscope and method for assembling components of an optical system

Abstract

An endoscope has a tubular shaft whose interior contains components, in particular lenses, spacers, diaphragms, prisms and filters of an optical system, said components being at least partially surrounded by a support piece made of shrunk material. It is proposed that the components be surrounded by a transparent and tube-sleeve-shaped shrunk material which has been shrunk before the components are introduced into the tubular shaft.

Claims

.[.1. An endoscope, comprising: a tubular shaft, having an inside face, an optical system having several components, said components of said optical system are contained in an interior of said tubular shaft, said components comprising at least two of the following: a lens, a spacer, a diaphragm, a prism and a filter, said components directly surrounded by a support piece made of a shrunk material, wherein said shrunk material is a transparent material, said support piece made of said transparent material has a shape of a tube, and said tube containing said components of said optical system has been shrunk prior to inserting said tube into said interior of said tubular shaft, for allowing a visual check of a position of said components relative to one another, and a gap located between an outside surface of said tube of shrunk material and said inside face of said tubular shaft..].

.[.2. The endoscope of claim 1, wherein said components are surrounded by a single tube made of said transparent material..].

.[.3. The endoscope of claim 1, wherein said shrunk transparent tube containing said components is fixed to the inside face of said tubular shaft..].

.[.4. The endoscope of claim 3, wherein said tube being fixed to said inside face of said tubular shaft by a radial expansion of said shrunk material..].

.[.5. The endoscope of claim 4, wherein said shrunk tube containing said components has in at least one area a configuration effecting a radial expansion during an axial shrinkage of said tube already inserted into said hollow shaft..].

.[.6. The endoscope of claim 5, wherein said configuration being at least one of thickened parts, beads and incisions of said transparent material..].

.[.7. The endoscope of claim 1, wherein said components comprise at least one of each of the following: a lens, a spacer, a diaphragm, a prism and a filter..].

.[.8. An endoscope, comprising: a tubular shaft having an interior and an inside face; an optical system including a plurality of components positioned in the interior of said shaft, the plurality of components comprising at least two of the following: a lens, a spacer, a diaphragm, a prism and a filter; a support piece comprising a shrunk material enclosing said optical system to fit into the interior of said tubular shaft and providing support for said optical system, said shrunk material directly surrounding said plurality of components; wherein said optical system is enclosed by and in contact with said shrunk material prior to insertion into said interior of said tubular shaft; and wherein said shrunk material is either transparent or translucent such that visual inspection of said plurality of components relative to each other may be conducted prior to insertion into said interior of said tubular shaft, and a gap located between an outside surface of said tube of shrunk material and said inside face of said tubular shaft..].

.[.9. The endoscope of claim 8, wherein said plurality of components is surrounded by a single tube made of said transparent or translucent material..].

.[.10. The endoscope of claim 8, wherein said shrunk transparent or translucent material containing said plurality of components is affixed to the inside face of said tubular shaft..].

.[.11. The endoscope of claim 10, wherein said shrunk transparent or translucent material is affixed to said inside face of said tubular shaft by a radial expansion of said shrunk transparent or translucent material..].

.[.12. The endoscope of claim 11, wherein said shrunk transparent or translucent material containing said plurality of components has in at least one area a configuration effecting a radial expansion during an axial shrinkage of said transparent or translucent material already inserted into the interior of said tubular shaft..].

.[.13. The endoscope of claim 11, wherein said configuration being at least one of thickened parts, beads and incisions of said transparent or translucent material..].

.[.14. The endoscope of claim 8, wherein said plurality of components comprise at least one of each of the following: a lens, a spacer, a diaphragm, a prism and a filter..].

.Iadd.15. An endoscope, comprising: a tubular shaft having an inside face; an optical system having several components contained in an interior of the tubular shaft; the components comprising at least two of the following: a lens, a spacer, a diaphragm, a prism, and a filter; the components directly surrounded by a shrunk material to form a shape of a tube; the tube containing the components shrunk prior to inserting the tube into the interior of the tubular shaft; the shrunk material adapted to permit a visual check of a position of the components relative to one another through the shrunk material; a gap located between an outside surface of the tube and the inside face of the tubular shaft to permit inserting the tube into the interior of the tubular shaft..Iaddend.

.Iadd.16. The endoscope of claim 15, wherein the shrunk material is shrunk by the application of heat..Iaddend.

.Iadd.17. The endoscope of claim 15, wherein the shrunk material transmits light to permit the visual check..Iaddend.

.Iadd.18. The endoscope of claim 17, wherein the shrunk material is transparent..Iaddend.

.Iadd.19. The endoscope of claim 17, wherein a transparency of the shrunk material permits the visual check..Iaddend.

.Iadd.20. The endoscope of claim 15, wherein the shrunk material is fixed to the inside face of the tubular shaft..Iaddend.

.Iadd.21. The endoscope of claim 20, wherein the shrunk material is fixed to the inside face of the tubular shaft by a radial expansion of the shrunk material..Iaddend.

.Iadd.22. The endoscope of claim 21, wherein the radial expansion of the shrunk material fills the gap..Iaddend.

.Iadd.23. The endoscope of claim 21, wherein the shrunk material has in at least one area a configuration effecting a radial expansion during an axial shrinkage of the shrunk material..Iaddend.

.Iadd.24. The endoscope of claim 23, wherein the configuration comprises at least one of thickened parts, beads, and incisions of the shrunk material..Iaddend.

.Iadd.25. The endoscope of claim 15, wherein the components comprise at least one of each of the following: a lens, a spacer, a diaphragm, a prism, and a filter..Iaddend.

.Iadd.26. An endoscope, comprising: a tubular shaft having an interior and an inside face; an optical system including a plurality of components positioned in the interior of the tubular shaft, the plurality of components comprising at least two of the following: a lens, a spacer, a diaphragm, a prism, and a filter; a shrunk material enclosing the optical system and providing support for the optical system, the shrunk material directly surrounding the plurality of components to form a shape of a tube; the optical system enclosed by and in contact with the shrunk material prior to insertion into the interior of the tubular shaft; the shrunk material adapted to permit visual inspection of the plurality of components relative to each other through the shrunk material; a gap located between an outside surface of the tube and the inside face of the tubular shaft to permit inserting the tube into the interior of the tubular shaft..Iaddend.

.Iadd.27. The endoscope of claim 26, wherein the shrunk material transmits light to permit the visual inspection..Iaddend.

.Iadd.28. The endoscope of claim 27, wherein the shrunk material is transparent..Iaddend.

.Iadd.29. The endoscope of claim 26, wherein the shrunk material is affixed to the inside face of the tubular shaft..Iaddend.

.Iadd.30. The endoscope of claim 29, wherein the shrunk material is affixed to the inside face of the tubular shaft by a radial expansion of the shrunk material..Iaddend.

.Iadd.31. The endoscope of claim 30, wherein the radial expansion of the shrunk material fills the gap..Iaddend.

.Iadd.32. The endoscope of claim 30, wherein the shrunk material containing the plurality of components has in at least one area a configuration effecting a radial expansion during an axial shrinkage..Iaddend.

.Iadd.33. The endoscope of claim 26, wherein the plurality of components comprises at least one of each of the following: a lens, a spacer, a diaphragm, a prism, and a filter..Iaddend.

.Iadd.34. The endoscope of claim 26, further comprising a retaining device for holding the tube and permitting the visual inspection of the plurality of components relative to each other through the shrunk material..Iaddend.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is described and explained in greater detail below on the basis of a number of selected illustrative embodiments and with reference to the attached drawings, in which:

(2) FIG. 1 shows a longitudinal section through a unit composed of a tube of transparent and shrinkable material and of optical components, namely rod lenses and spacers, before shrinkage,

(3) FIG. 2 shows a cross section of a retaining device in which the unit shown in FIG. 1 is inserted, specifically upon shrinkage,

(4) FIG. 3 shows a longitudinal section through an endoscope during assembly, into which endoscope the unit shown in FIG. 1, after it has been shrunk in the retaining device 3 shown in FIG. 2, is inserted into the tubular shaft, and

(5) FIG. 4 shows, on a greatly enlarged scale, a partial longitudinal section through a shaft of an endoscope in whose tubular shaft a unit according to the invention is inserted, the left-hand half showing the unit fixed on the inside face of the tubular shaft by adhesive contacts, and the right-hand side showing it being fixed by means of further shrinkage.

DETAILED DESCRIPTION OF THE INVENTION

(6) In FIG. 1, a unit, designated in its entirety by reference number 10, comprises a tube 12 made of transparent and shrinkable material 14. A plurality of components 16 of an optical system are introduced into the tube 12, specifically, as viewed from left to right, a rod lens 18, whose external diameter corresponds approximately to the clear internal diameter of the tube 12, a tubular and stiff spacer 20, a further rod lens 18, a further spacer 21, and a further rod lens 18.

(7) This unit 10 is shown only by way of example, and other components such as filters, diaphragms or the like can of course also be included. It is also possible to provide closure windows at the ends or, in the case of an angled side view, suitable prisms.

(8) By virtue of the transparency of the material 14, it is possible to check the desired correct fit of these components 16 relative to one another from the outside, for example to check whether the opposing end faces of the two rod lenses 18 and 18 bear exactly on the spacer 20.

(9) For the shrinking process, the unit 10 is inserted into a retaining device 30, as is shown in FIG. 2.

(10) The retaining device 30 has an elongate body 32 whose length corresponds to least to the length of the unit 10.

(11) Cut out on the top face of the body 32 there is a longitudinally extending groove 34 which is configured in such a way that the unit 10 can be inserted into this groove, the unit 10 protruding slightly above the upper edge of the retaining device.

(12) A roughly plate-shaped object 36 is placed onto this protruding area and bears with an at least partial form fit on the top face of the unit 10, as it were pressing said unit 10 into the groove 34.

(13) In this way, the unit 10 is inserted and fixed in the retaining device 30 in such a way that a uniform shrinking of the material 14 of the tube 12 is possible, but with the unit still being fixed in position.

(14) Alternatively or in addition, the position can be fixed by use of a partial vacuum. For this purpose, at least one opening 35 is provided in the bottom of the groove 34 and can be connected via an attachment piece 39 to a partial vacuum source (not shown here).

(15) As is known per se, in the actual shrinking process, energy is supplied from an energy source 38 and causes the material 14 of the tube 12 to shrink.

(16) One energy source is, for example, heat, if the material is designed such that it shrinks when heated. It is of course also possible to heat the retaining device 30 itself or to cause heated fluid to flow onto the retaining device.

(17) After the shrinkage, the object 36 is taken off and the now shrunk unit 10 is removed from the retaining device 30.

(18) By virtue of the transparency of the material 14 which is still present even after the shrinkage, it is possible once again to check, from the outside, the correct fit of the individual components 16 relative to one another.

(19) The shrunk unit 10 is then inserted into a tubular shaft 42 of an endoscope 40, as is shown in FIG. 3.

(20) The endoscope 40 shown in FIG. 3 is represented highly schematically and, in addition to the tubular shaft 42 also referred to as inner tube, it also comprises an outer tube 44 of greater diameter which is mounted in a housing 50. The tubular shaft 42 is received in the interior of the outer tube 44.

(21) As is normally the case, a light guide 46 is arranged in an approximately crescent-shaped space between tubular shaft 42 and outer tube 44, said light guide 46 leading to a laterally angled light guide attachment 48. In the illustrative embodiment shown, the light guide 46 is composed of a bundle of light-conducting glass fibers. The state shown in FIG. 3 is a state of partial assembly in which the eyepiece cup is still to be applied to the right-hand end, and, if appropriate, closure components or the like to the left-hand end.

(22) FIG. 4 shows a cross section, on a greatly enlarged scale, through the shaft of an endoscope 40, and, for the sake of clarity of the drawing, a slightly shorter spacer 20 is shown here separating the two rod lenses 18 and 18 from one another.

(23) From the cross-sectional view in FIG. 4 it will be evident that the unit 10 is inserted after shrinkage into the tubular shaft 42 received in the outer tube 44. The external diameter is chosen in such a way that a small gap 52 is present between the outside face of the shrunk tube 12 and the inside face 56 of the tubular shaft 42.

(24) In FIG. 4, for the sake of clarity of the drawing, this gap 52 is shown much larger than it really is.

(25) The width of the gap is chosen such that the shrunk unit 10 can be pushed into the tubular shaft 42 easily, or at any rate with minimal resistance.

(26) FIG. 4 shows, on the left-hand side, that the unit 10 is fixed on the inside face 56 of the tubular shaft 42 via an adhesive 54. The adhesive 54 can either be introduced through openings (not shown here) from the outside or can be applied to the shrunk unit 10 before the latter is inserted into the tubular shaft 42.

(27) The right-hand end of FIG. 4 shows that the unit 10 is fixed to the inside face 56 of the tubular shaft 52 by further shrinkage of the tube and associated radial expansion, in which case, as has already been mentioned, the shrinkable tube can be geometrically designed in such a way that, for example by provision of beads, incisions or other configurations which promote expansion at predetermined locations, this expansion takes place in a specific manner during the further shrinking process.

(28) This possibility is chosen when the material 14 of the tube 12 permits two shrinking processes, namely a first or preliminary shrinking process for fixing the components to one another, for example in the retaining device 30 shown in FIG. 2, and then, after insertion into the tubular shaft 42 as shown in FIG. 4, a further shrinking and radial expansion for filling the gap 52.