GB2352922A

GB2352922A - Endoscope

Info

Publication number: GB2352922A
Application number: GB0013515A
Authority: GB
Inventors: Timo Wenzel; Andreas Mueckner; Mathias Kraas
Original assignee: Olympus Winter and Ibe GmbH
Current assignee: Olympus Winter and Ibe GmbH
Priority date: 1999-06-02
Filing date: 2000-06-02
Publication date: 2001-02-07
Also published as: JP2001008885A; DE19925323A1; FR2794535A1; GB0013515D0

Abstract

An electronic endoscope includes a tubular shaft (1), arranged at the distal end of which there is a video camera (5) connected to a video line (9) extending through the shaft (2), an illumination device (4), which is arranged to radiate from the distal end of the shaft and is supplied by a light supply line (4) extending through the shaft, and a main body (14), which is provided at the proximal end of the shaft and is connected to the shaft and through which extend two lines (4, 9), which extend away from the main body to externally disposed devices for image processing (23) and for light supply (20). The proximal end of the shaft (2) is releasably connected to the main body (14), which is constructed in the form of a coupling body, by means of a mechanical coupling (10, 17), which has a video transmission coupling (7, 19) and a light supply coupling (4, 4').

Description

2352922 ENDOSCOPE The invention relates to an endoscope of the type

including a tubular shaft, arranged at the distal end of which there is a video camera, connected to which is a video signal line extending through the shaft, an illumination device, which is arranged to radiate light from the distal. end of the shaft and connected to which is a light supply line extending through the shaft, and a main body, which is provided at the proximal end of the shaft and is connected thereto and through which extend a video signal line and a light supply line.

In known endoscopes of this type, as described in US 4858001, the shaft and main body are rigidly connected. In order to replace the shaft, if this is desired, for instance, because a different shaft length or a different viewing angle of the video camera is required, the entire device must be exchanged and the lines extending from the main body to the devices for image processing and light supply must be repositioned.

In an optical endoscope with optical image transmission as disclosed in JP57-156851 U, which is not of the type referred to above, it is known to provide the shaft, which affords one portion of the optical image transmission system, replaceably on the main body with a coupling in which respective portions of the optical beam path of the image transmission system and the light supply line, constituted by a light guiding fibre bundle are coupled. This construction produces considerable problems as regards the precise coupling of the beam path.

It is the object of the present invention to construct an endoscope of the type 2 referred to above more simply as regards its construction and handling in relation to exchanging the shaft.

According to the present invention an endoscope of the type referred to above is characterised in that the proximal end of the shaft is releasably coupled to the main body, which is constructed in the form of a coupling body, by means of a mechanical coupling which includes a video signal coupling and a light supply coupling. In use, the video signal line and the light supply line in the main body are connected to external devices for image processing and light supply, respectively.

In accordance with the invention, the main body is constructed merely as a simple coupling body which may be mechanically releaseably coupled to the proximal end of the shaft and has couplings for the video line and the light supply line and provides outlets for the lines to external devices for image processing and light supply. A very simple construction of the main body is thus provided which may be small and which may constitute substantially only a cable terminal member. After decoupling, the shaft can be replaced with another shaft which has a different length or a different viewing direction, e.g.

looking straight ahead instead of looking obliquely. Advantages are also produced by the decouplable arrangement as regards cleaning and sterilisation of the components of medical endoscopes which may be used within the body since the externally located main body, which does not come into contact with the field of operation, need not necessarily be maintained sterile with the same care as the shaft which is to be introduced into the body, which can be sterilised separately, e.g. by autoclaving.

3 The illumination device can, for instance, comprise light emitting diodes arranged distally in the shaft, whereby the light supply line is an electrical power line. This offers advantages as regards the coupling between the shaft and the coupling body. It is, however, preferred that the illumination device is constructed in the form of a light guiding fibre bundle which also constitutes the light supply line in the tubular shaft and is arranged to radiate light from its distal end. This construction offers the advantages usual in endoscopy. The shaft then has the conventional construction with an internally situated light guiding fibre bundle. The light supply coupling is advantageously constituted by opposed end surfaces of the two light guiding fibre bundles, which are in alignment in the coupled position.

The mechanical coupling can be provided in the form of a rotary coupling but is advantageously of rotationally locking type which provides, in particular, advantages relating to the coupling of electric lines which can be connectable by means of plug pins, whereas with a rotary coupling e.g. electrical sliding contacts or an optical coupling for a video signal line in the form of an optical signal line, would be necessary.

The video signal line and the light supply line can extend separately away from the coupling body. However, they advantageously extend away in a common connecting cable, which provides advantages as regards neatness of the working area. The connecting cable preferably leaves the main body in the axial direction of the shaft. The axial exit of the connecting cable renders unimpeded rotation of the endoscope about its axis possible, which is frequently necessary, for instance in the case of a laterally viewing video camera, in order to change the viewing angle.

4 One embodiment of the invention is illustrated schematically and by way of example in the accompanying drawing which is an axial sectional view of an electronic endoscope in accordance with the invention in the decoupled state.

The single Figure shows a shaft I and a shaft tube 2, the distal end of which is closed in a sealed manner with a window 3. The window 3 can also be omitted if no importance is attached to sealing the interior for reasons of sterility and the like.

Provided annularly in engagement with the inner surface of the shaft tube 2 is an annular light guiding fibre bundle 4, the distal end of which radiates light through the window 3 onto the field of view. Secured within the light guiding fibre bundle 4 at the distal end of the shaft tube 2 is a video camera 5. The objective 6 can, as shown, be constructed to look straight ahead through the window 3 or to look e.g. obliquely.

The light guiding fibre bundle 4 extends over the length of the shaft tube 2 and terminates at its proximal end. The tube 2 can again be sealed at this point with a window, which is not shown. Provided within the light guiding fibre bundle 4 at the proximal end of the shaft tube 2 is a plug body 7 with electrical contact pins 8, which extend in the axial direction of the shaft I and are connected to the individual electrical leads of a video line 9 which extends over the length of the shaft I and transmits electrical signals from the camera 5.

Secured on the proximal end region of the shaft tube 2 is a threaded ring 10 with an external screw thread and an axial nose 11 at one angular position.

Secured at the end of a connecting cable 12 by means of a socket 13 is a coupling body 14. The coupling body 14 has a tubular body 15, whose distal internal diameter matches the external diameter of the shaft tube 2. It has an axial slot 16 for rotational locking engagement with the nose 11.

Rotatably mounted on the tubular body 15 is a threaded sleeve 17 whose internal thread may be screwed onto the external thread of the threaded ring 10.

When these two are screwed together the end of the shaft tube 2 moves axially into engagement with an external flange 18 on the tubular body 15.

When this mechanical coupling 10, 17,11,16 is in the engaged position, the proximal end of the annular light guiding fibre bundle is opposed to the end of an annular light guiding fibre bundle 4' which is secured in the tubular body 15 and converges from the coupling point towards the connecting cable 12.

Secured within the annular end of the light guiding fibre bundle 4 is a socket member 19 with sockets, shown in chain lines, for receiving the contact pins 8 of the plug body 7. An extension 9' of the video line extends within the connecting cable 12, which, as shown, extends away from the tubular body 15 in the axial direction.

As illustrated, the connecting cable 12 extends to an externally positioned cold light source 20, in which, as shown in chain lines, the end of the light guiding fibre bundle 4' is illuminated in a conventional manner by a lamp 21 with a reflector 22.

6 The video line 9' branches out of the connecting cable 12 and is connected to an image processing device 23 in which the electronic image signals are processed and on which a monitor 24 for reproducing the image is provided in the illustrated exemplary embodiment.

In a modification of the illustrated embodiment, the coupling body 14 is provided with separate outlets for the light guiding fibre bundle 4' and the video line 9'. It can also be differently constructed spatially, e.g. with an ergonomic construction which is easy to grip, for instance with a pistol grip and a laterally extending connecting cable 12.

The mechanical coupling between the coupling body 14 and shaft I can also be produced in a different manner, e.g. by means of a bayonet coupling or a screw coupling which are released in a different manner.

The mechanical coupling can also be of rotary construction. In this case the annular disposition of the light guiding fibre cable 4,4', illustrated in the Figure, is of advantage since it couples satisfactorily in all rotary positions. The light guiding fibre cable can also be of non-rotationally symmetrical construction with a rotationally fixed coupling. With a rotary coupling, the video line 9,9' must be coupled in some other manner, e.g. by means of electrical slip rings. If the video line is in the form of an optical signal cable, an optical coupling will need to be provided for it.

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Claims

1. An endoscope including a tubular shaft, arranged at the distal end of which there is a video camera, connected to which is a video signal line extending through the shaft, an illumination device, which is arranged to radiate light from the distal end of the shaft and connected to which is a light supply line extending through the shaft, and a main body, which is provided at the proximal end of the shaft and is connected thereto and through which extend a video signal line and a light supply line, the proximal end of the shaft being releasably coupled to the main body, which is constructed in the form of a coupling body, by means of a mechanical coupling which includes a video signal coupling and a light supply coupling.

2. An endoscope as claimed in Claim I in which the video signal line and the light supply line in the main body are connected to external devices for image processing and light supply, respectively.

3. An endoscope as claimed in Claim 1 or 2 in which the illumination device is constructed in the form of a light guiding fibre bundle which also constitutes the light supply line in the tubular shaft and is arranged to radiate light from its distal end.

4. An endoscope as claimed in Claim 3 in which the light supply line in the main body comprises a light guiding fibre bundle and the light supply coupling is constituted by opposed end surfaces of the two light guiding fibre bundles, which are in alignment in the coupled position.

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5. An endoscope as claimed in Claim I in which the mechanical coupling is of rotationally locking type.

6. An endoscope as claimed in Claim 1, in which the video line and the light supply line in the main body extend away from the main body in a common connecting cable.

7. An endoscope as claimed in Claim 5, in which the connecting cable 10 leaves the main body in the axial direction of the shaft.