Optical coupling, endoscopy arrangement and corresponding use

An optical coupling having a coupling part and a mating coupling part which are detachably connected to one another is provided, a connection element being arranged on the coupling part and a fitting mating connection element being arranged on the mating coupling part. These connection elements together form a common optical channel, and the mating connection element is arranged with play in the mating coupling part and without play in the coupling part.

INCORPORATION BY REFERENCE

The following documents are incorporated herein by reference as if fully set forth: German Patent Application No. 10 2021 102 653.9, filed Feb. 4, 2021.

TECHNICAL FIELD

The invention relates to an optical coupling having a coupling part and a mating coupling part which are detachably connected to one another, a connection element being arranged on the coupling part and a fitting mating connection element being arranged on the mating coupling part, these connection elements forming an optical channel in relation to one another. Such an optical coupling is known.

The invention also relates to an endoscopy arrangement having an optical coupling. Such an endoscopy arrangement is known.

The invention also relates to the use of an optical coupling in endoscopy. Such a use is known.

BACKGROUND

Optical couplings of this type are known and are used, for example in endoscopes, to connect a light source or a light guide to a corresponding light guide path in an endoscope.

The invention is based on the object of aligning the transition between the two partial optical paths, for example between the connection element and the mating connection element, as accurately as possible, for example in order to prevent unnecessary instances of heat development, heat losses or—in the case of image guidance—optical imaging aberrations. The invention is further based on the object of minimizing the sum of the manufacturing tolerances of the parts, and of simplifying the mechanical structure and the assembly of the components. The objects are achieved by the use of one or more of the features described herein. Advantageous embodiments are described below and in the claims.

To achieve these objects, the invention provides in the case of an optical coupling of the type set forth at the outset, that the mating connection element is arranged with play in the mating coupling part and without play in the coupling part. What this achieves is that the coupling part aligns the connection element and the mating connection element with respect to one another such that manufacturing tolerances have less influence. Over determination of the alignment is consequently rendered avoidable.

An advantageous embodiment according to the invention can provide for the connection element to be in the form of a fiber cone. Alternatively or additionally, provision can be made for the mating connection element to be in the form of a fiber socket. Alternatively or additionally, provision can be made for the coupling part to be in the form of a connection socket. Alternatively or additionally, provision can be made for the mating coupling part to be in the form of a fiber connection socket. Thus, different functions of the parts can be realized and specific structural realizations can be provided.

In a further advantageous embodiment, provision can be made for a guide surface to be formed on the coupling part and to arrange the connection element and the mating connection element in relation to one another. Consequently, aligning the mating connection element with the coupling part is easily attainable.

A cylindrical guide surface is particularly expedient. Consequently, it is possible to attain an optimal arrangement between connection element and mating connection element. Consequently, it is furthermore possible to minimize the sum of the manufacturing tolerances, and mechanical structure and the assembly of the components can be simplified. In particular, it is advantageous here that the guide surface for the connection element and the mating connection element can be produced in one work step.

In a further advantageous embodiment, provision can be made for the mating coupling part to be screwed to a main body by way of a fastening thread. Consequently, it is possible to obtain a simple and detachable connection between the main body and the mating coupling part.

In a further advantageous embodiment, provision can be made for the mating coupling part to be screwed to the coupling part by way of a coupling thread. Consequently, it is possible to obtain a simple and detachable connection between the coupling part and the mating coupling part.

In a further advantageous embodiment, provision can be made for a breakaway torque of the fastening thread to be greater than a breakaway torque of the coupling thread. Consequently, by using a smaller breakaway torque or torque, the mating coupling part can be separated from the coupling part without the mating coupling part being separated from the main body. Consequently, the manufacturing or installation method can moreover be simplified.

Such a selective disconnection is required, for example, during the assembly or during the grinding of optical guides such as fiber guides or optical fibers, for example.

The magnitude of the breakaway torques can be defined by the diameters and the pitches of the threads. By way of example, the fastening thread can take the shape of a fine thread as M8×0.5 with a small pitch. The coupling thread can take the shape of a fine thread, for example, as M9×1.0 with a greater pitch. The diameters of the fastening threads and the coupling threads may be the same, with a different pitch of the threads possibly being required in such a case.

In a further advantageous embodiment, provision can be made for the mating connection element to have a channel opening which narrows in the direction of the connection element. Consequently, the positioning of optical elements, for example fiber guides or optical fibers, within the channel opening and in the direction of the connection element can be simplified. By way of example, the channel opening can take the shape of a trumpet. What is likewise advantageous here is that friction between the optical elements, for example the fiber guides, and the mating connection element can be reduced. Consequently, it is possible to prevent damage to the optical elements. A further advantage that may arise here is that the assembly, for example of the optical fibers in the mating connection element, is simplified.

In a further advantageous embodiment, provision can be made for an optical guide to be arranged in the connection element. Provision can be made for the optical guide to be connected to the connection element in integrally bonded fashion and/or in frictionally connected fashion. By way of example, the optical guide could be in the form of optical fibers or in the form of a glass part, for example a glass lens. By way of example, the integral bond can be obtained by means of an adhesive bond or by soldering. Consequently, optimal positioning of the optical guide and, additionally, sealing can be ensured.

Alternatively or additionally, provision can be made for an optical guide to be arranged in the mating connection element. Provision can be made for the optical guide to be connected to the mating connection element in integrally bonded fashion and/or in frictionally connected fashion. By way of example, the integral bond can be obtained by means of an adhesive bond or by soldering. Consequently, optimal positioning of the optical guide in relation to the mating connection element can be ensured.

In a further advantageous embodiment, provision can be made for the optical guide to be a light guide. Consequently, an optimal application can be ensured. Consequently, light losses or heat losses can furthermore be reduced during a light transmission by virtue of an accurate alignment without a gap being attainable.

Alternatively or additionally, provision can be made for the optical guide to be an image guide. Consequently, an optimal application can be ensured. Consequently, imaging aberrations can furthermore be reduced during an image transmission by virtue of an accurate alignment without a gap being attainable.

In a further advantageous embodiment, provision can be made for a glass body to be arranged in the connection element and a fiber guide to be arranged in the mating connection element. Consequently, optimal positioning between the glass body and the fiber guide can be ensured. In this context, it is advantageous if the glass body and the connection element are tightly connected. Consequently, it is possible to prevent an unwanted ingress or egress of liquid. It generally is the case that the fiber guide comprises a bundle of optical fibers which, although densified and adhesively bonded, have not been hermetically sealed, and so moisture can penetrate between the individual optical fibers.

The invention moreover relates to an endoscopy arrangement comprising an optical coupling having the features according to the invention, for example wherein the optical channel is used for a light transmission and/or an image transmission. Consequently, a reduction in manufacturing tolerances or an increase in product quality can be attained in a preferred application.

In an advantageous embodiment, provision can be made for the coupling part to be arranged proximally within the endoscopy arrangement. What can be advantageous here is that the part with play is not arranged directly at the mating coupling of the optical cable.

Alternatively, provision can be made for the coupling part to be arranged distally. Consequently, a structural alternative can be provided.

By way of example, proximal may denote proximity to the surgeon, for example the physician, or distance from the examination object (e.g., patient); by way of example, distal may denote proximity to the examination object, for example the patient.

The invention moreover relates to the use in endoscopy of an optical coupling having the features according to the invention, for example for light transmission. Consequently, it is possible to attain exact positioning of optical guides or an improved structure.

DETAILED DESCRIPTION

In the following description of various exemplary embodiments of the invention, elements that correspond in terms of their function receive corresponding reference numerals, even in the case of a deviating design or shape.

FIG.1shows an optical coupling according to the prior art.

The optical coupling1comprises a coupling part2, a mating coupling part3, a connection element4and a mating connection element5.

The optical coupling1is fastened to a main body9. Fastening can be achieved by means of a thread or by means of welding, for example.

The optical coupling1has an optical channel6, which is continuous through a bore of the connection element4, through a bore of the mating connection element5, and through a bore of the mating coupling part3.

The mating coupling part3is screwed to the coupling part2by way of a coupling thread10.

The diameters of the bore of the connection element4and of the bore of the mating connection element5should be the same.

A guide surface7takes shape on the coupling part2and is in direct contact with the connection element4. This guide surface7is cylindrical.

The mating connection element5and the connection element4are arranged in relation to one another. The positioning of these two elements is determined by the contact between connection element4and coupling part2, in particular the guide surface7, the contact between coupling part2and mating coupling part3, and the contact between mating coupling part3and mating connection element5. Accordingly, three or more manufacturing tolerances have to be taken into account in this example, these manufacturing tolerances adding up and leading to a poor (non-optimal) alignment of the end faces of connection element4and mating connection element5, and as a consequence possibly leading to more rejection of material or components during a quality analysis.

The mating coupling part3has a shoulder on which the mating connection element5is seated.

FIG.2shows an optical coupling according to this invention.

The optical coupling1comprises a coupling part2, a mating coupling part3, a connection element4and a mating connection element5.

The connection element4may be in the form of a fiber cone. The mating connection element5may be in the form of a fiber socket. The coupling part2may be in the form of a connection socket. The mating coupling part3may be in the form of a fiber connection socket.

The optical coupling1is fastened to a main body9. The main body9belongs to an endoscope shaft or an endoscope. Fastening is achieved by means of a fastening thread8. The fastening thread8takes shape between the mating coupling part3and the main body9.

The optical coupling1has an optical channel6, which is continuous through a bore of the connection element4, through a bore of the mating connection element5, and through a bore of the mating coupling part3.

The mating connection element5is arranged without play in the coupling part2and the mating connection element5is arranged with play in the mating coupling part3. In this context, without play means that there is direct contact between the mating connection element5and the coupling part2transversely to the axial direction. In this context, with play means that there is no direct contact between the mating connection element5and the mating coupling part3transversely to the axial direction.

The mating coupling part3is screwed to the coupling part2by way of a coupling thread10.

The breakaway torque of the fastening thread8is greater than the breakaway torque of the coupling thread10. The magnitude of the breakaway torques can be defined by way of the diameters and the pitches of the threads. By way of example, the fastening thread8can take the shape of a metric fine thread M8×0.5. By way of example, the coupling thread10can take the shape of a metric fine thread M9×1.0. This can ensure selective opening of screwed together parts during the assembly and during manual activities, or this can prevent damage to fiber guides, for example.

A guide surface7takes shape on the coupling part2and is in direct contact with the connection element4and the mating connection element5. The guide surface7is cylindrical. The guide surface7aligns the connection element4and the mating connection element5in relation to one another. The guide surface7may be conical in another exemplary embodiment.

The connection element4and the mating connection element5are arranged in relation to one another. The positioning of these two elements is determined by the contact between connection element4and coupling part2and the contact between coupling part2and mating connection element5. Accordingly, two or more manufacturing tolerances should be considered in this example, and consequently fewer tolerances need to be considered than in the example ofFIG.1, which describes the prior art. In this respect, the example ofFIG.2represents an improvement over the example ofFIG.1, for example in relation to mechanical manufacturing and positioning with a precise fit. Optimal positioning between connection element4and mating connection element5, and consequently between the optical guides situated in the optical channel, is desirable, for example to prevent light losses or excessive development of heat.

The connection element4has a shoulder which is seated on the coupling part2. There is an integrally bonded connection between the connection element4and the coupling part2. The integral bond is ensured by a welded seam and is consequently hermetically sealed. The integral bond can be attained by way of an adhesive in another exemplary embodiment. What is advantageous here is that an ingress of liquid into, or an egress of liquid from, the optical coupling can be prevented.

The mating coupling part3has a shoulder on which the mating connection element5is seated.

There is an integrally bonded connection between the main body9and the coupling part2. The integral bond is ensured by a welded seam and is consequently welded in hermetically sealed fashion. The integral bond can be attained by way of an adhesive in another exemplary embodiment. What is likewise advantageous here is that an egress of liquid from, or an ingress of liquid into, the optical coupling can be prevented.

An optical guide (not illustrated inFIG.2) is arranged in the connection element4. A fiber guide (not illustrated inFIG.2) is arranged in the mating connection element5.

By way of example, the fiber guide can be a light guide or an image guide or a combination of both. The fiber guide may comprise a bundle of optical fibers.

The mating connection element5has a channel opening11, which narrows in the direction of the connection element4. The shape of the channel opening11may be described as trumpet shaped. In this way, it is possible to attain improved positioning of for example fiber guides and the associated optical fibers, and potential damage due to friction between the fiber guides and the surface of the mating connection element5can be reduced. The optical fibers of the fiber guide in the mating connection element5are densified and adhesively bonded at the contact point to the optical guide in the connection element4but are not hermetically sealed. The optical fibers may guide liquid in capillary fashion. A structure as described herein is expedient for the assembly, which contains for example the polishing of optical fibers and the adhesive bonding of optical fibers.

In the case illustrated inFIG.2, provision is made for the main body9to be connected to an endoscope shaft (not illustrated inFIG.2) and for the light source13(not illustrated inFIG.2) to act from above and for the light-guide cable14(not illustrated inFIG.2) to be guided to the connection element4from above. The light-guide cable14has a mating coupling (not illustrated inFIG.2), which is placed directly on the optical coupling1and which is detachably connected to the connection element4. A glass body (not illustrated inFIG.2) is arranged in the connection element4. The connection between the glass body and the connection element4is hermetically sealed, and so liquid ingress or liquid egress can be prevented. The glass body may be a glass lens. In another exemplary embodiment, the glass body may be formed from plastic. The coupling part2is arranged proximally inFIG.2.

However, this is not the only option. The coupling part may be arranged distally in another exemplary embodiment. Thus, it is possible for the optical coupling1to be accordingly installed in reverse.

The endoscopy arrangement12comprises a light source13which is connected to an endoscope16via a light-guide cable14. The endoscope16inter alia has an optical channel for light transmission.

The light-guide cable14is connected to the endoscope16by means of a light-guide connection15.

The endoscope16moreover comprises an optical coupling1(not illustrated inFIG.3) according to this invention and according to the claimed features.

An optical coupling having a coupling part and a mating coupling part which are detachably connected to one another is disclosed, a connection element being arranged on the coupling part and a fitting mating connection element being arranged on the mating coupling part, these connection elements together forming a common optical channel, wherein the mating connection element is arranged with play in the mating coupling part and without play in the coupling part.

LIST OF REFERENCE SIGNS