Surgery – Endoscope – Having imaging and illumination means
Reexamination Certificate
1999-06-11
2001-05-15
Cohen, Lee (Department: 3739)
Surgery
Endoscope
Having imaging and illumination means
C600S181000, C362S583000, C362S574000
Reexamination Certificate
active
06231503
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to an endoscopic light source apparatus for supplying illuminating light to an endoscope.
Endoscopic light source apparatus are generally of such a type that rays of illuminating light emitted from a light source, such as a built-in lamp are allowed to converge with a condenser lens and the illuminating light entrance end face of an endoscope's lightguide connector is connected near the position of their convergence.
Such endoscopic light source apparatus are useful in combination with various types of endoscopes to constitute an endoscopic system. That is, various types or kinds of endoscopes are preliminarily prepared depending on various intended uses, and selectively connected for use with a single unit of light source apparatus. To this end, the lightguide connector to be connected to the light source apparatus has the same shape and size in spite of the use of different models of endoscope. Therefore, any one of endoscopes belonging to an endoscopic system can be connected to a light source apparatus belonging to the same endoscopic system.
If the endoscopic system itself is renewed for various reasons such as making substantial modification, it is often necessary to change the size and shape of the joint between the endoscope's lightguide connector and the light source apparatus.
In renewal of the endoscopic system, there is no big problem with the light source apparatus since only one unit need be replaced. However, substituting an entirely new set of endoscopes often means an excessive economic burden on the user. To deal with this problem, the light source apparatus in a new system is generally adapted to be of such a compatible type that not only the endoscopes for the new system but also those for the old system can be connected.
In this connection, the endoscope belonging to the old system generally has a relatively long insertion section on the lightguide as a support to the light source apparatus in order to secure the positional accuracy of the illuminating light entrance end face of the endoscope's lightguide connector relative to the convergence position of the rays of illuminating light emitted from the light source lamp. In contrast, the endoscope belonging to the new system does not require such long insertion section on the lightguide since the positional accuracy can be secured by other means or mechanisms, and therefore the design trend is making the insertion section of the lightguide shorter from the viewpoint of space-saving.
However, some types of the endoscopes belonging to the new endoscopic system require the light source apparatus belonging to the new endoscopic system to have a light attenuating filter in the form of a metal screen between a lamp, i.e. the light source, and the illuminating light entrance end face of a lightguide connector in order to ensure that heat rays included in the illuminating light radiated from the lamp will not raise the temperature of the lightguide connector portion to an unduly high level that may cause a burn to the operator. An endoscope that has a relatively long insertion section on a lightguide similarly to the endoscope belonging to the old endoscopic system (and thus a distance between the light source lamp and the illuminating light entrance end face of the lightguide connector is inevitably short), an endoscope that uses a thermally weak material, such as plastic fiber (which is advantageous in view of cost reduction and which would be put into practice near future), as the lightguide, etc. are included in those types of the endoscopes.
A problem with a light source apparatus of this design is that if it is connected to an endoscope in a system that does not have to use such a light attenuating filter, the efficiency of illumination is insufficient to produce an adequate brightness of illuminating light whereas if the combination is reversed, the temperature of the lightguide connector portion is raised to an unduly high level that may potentially cause a burn to the operator.
SUMMARY OF THE INVENTION
The present invention has been accomplished under these circumstances, and has as an object providing an endoscopic light source apparatus to which either an endoscope in a system that requires a light attenuating filter in the optical path of illuminating light or an endoscope in a system that does not need such a light attenuating filter can be connected for use without any problem.
To achieve the stated object, the present invention provides such an arrangement that the light attenuating filter is inserted into or retracted from the optical path of illuminating light depending upon the length of the lightguide connector to be connected to the light source apparatus. The present invention further provides such an arrangement that, irrespective of the length of the lightguide connector, the illuminating light entrance end face of the lightguide connector is always located near the position in which the rays of illuminating light converge. Accordingly, various types of endoscopes can be used in the appropriate way irrespective of whether they are intended for a system that requires a light attenuating filter in the optical path of illuminating light or for a system that needs no such filters.
The present invention provides, as an embodiment, an endoscopic light source apparatus in which the illuminating light entrance end face of an endoscope's lightguide connector is connected near a converging position in which the rays of illuminating light emitted from a light source are allowed to converge with a condenser lens, characterized by having an illuminating light converging mechanism in which said lightguide connector to be connected displaces said condenser lens in a direction parallel to the optical axis of the illuminating light so that irrespective of the length of said lightguide connector, the illuminating light entrance end face of said lightguide connector is located near the converging position of said rays of illuminating light, and a filter inserting and retracting mechanism which moves in operative association with said illuminating light converging mechanism such that a light attenuating filter is inserted into or retracted from said rays of illuminating light depending upon the length of said lightguide connector.
If desired, said filter inserting and retracting mechanism may be adapted to be driven by the operation of said illuminating light converging mechanism. Alternatively, it may be adapted to allow said light attenuating filter to be inserted or retracted in a direction normal to said optical axis of the illuminating light.
In another modification, said light attenuating filter may be inserted into said rays of illuminating light when said lightguide connector is long enough but it is not inserted into said rays of illuminating light when said lightguide connector is short. Alternatively, said light attenuating filter may be inserted into said rays of illuminating light when said lightguide connector is short but it is not inserted into said rays of illuminating light when said lightguide connector is long enough.
In a preferred embodiment, the rays of illuminating light emitted from said light source may consist of rays of both parallel light and diffusing light.
The present disclosure relates to the subject matter contained in Japanese patent application No. Hei. 10-163292(filed on Jun. 11, 1998), which is expressly incorporated herein by reference in its entirety.
REFERENCES:
patent: 4862258 (1989-08-01), Kidawara et al.
patent: 4951133 (1990-08-01), Onoda
patent: 5823943 (1998-10-01), Tomioka et al.
patent: 5876327 (1999-03-01), Tsuyuki et al.
Iriyama Kenichi
Sugimoto Hideo
Asahi Kogaku Kogyo Kabushiki Kaisha
Cohen Lee
Greenblum & Bernstein P.L.C.
Ram Jocelyn
LandOfFree
Endoscopic light source apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Endoscopic light source apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Endoscopic light source apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2543943