Hard endoscope with improved light dispersion

• US 4,576,147 A
• Filed: 07/30/1984
• Issued: 03/18/1986
• Est. Priority Date: 07/16/1981
• Status: Expired due to Term

• Current Assignee: Olympus Optical Corporation Limited (Olympus Corporation)
• Original Assignee: Olympus Optical Corporation Limited (Olympus Corporation)
• Inventors: Hashiguchi, Toshihiko
• Primary Examiner(s): Coven, Edward M.
• Assistant Examiner(s): Hindenburg, Max F.
• Application Number:
  US06/634,673
• Time in Patent Office: 596 Days
• Field of Search: 128/4-8, 350/96.26
• US Class Current: 600/129
• CPC Class Codes: A61B 1/0011 Manufacturing of endoscope parts
• CPC Class Codes: A61B 1/00165 with light-conductive means, e.g. fibre optics A61B1/07 takes precedence
• CPC Class Codes: A61B 1/00179 for off-axis viewing
• CPC Class Codes: A61B 1/0623 for off-axis illumination
• CPC Class Codes: Y10S 600/92 Method of making endoscopes

Abstract

A hard endoscope is disclosed having a hard outer tube, an inner tube disposed eccentrically within the outer tube, such that a gap is left between the two tubes, the inner tube having an observing optical system disposed therein, a plurality of light guide fibers disposed within the gap, the light guide fibers being adapted to transmit light along the length thereof and an end surface formed by the termination of the outer tube, the inner tube, and the light guide fibers. The outer tube has a tip member disposed on the end thereof, the tip member having an opening and forming a curved inner peripheral surface. The inner tube has a tip member disposed on the end thereof, the tip member having a curved outer peripheral surface and a slit for receiving reflected light, and the inner tube tip member terminating at the above-mentioned opening. The outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube are curved in generally the same direction. The light guide fibers disposed between the two peripheral surfaces are also curved, curves thereof having various different curvatures, such that the light which is emitted therefrom is emitted in different directions.

Claims

1. A hard endoscope, comprising:

a hard outer tube having an inner peripheral surface;

an inner tube disposed eccentrically within said outer tube such that said inner tube contacts a portion, defined as the upper portion, of said inner peripheral surface of said outer tube, thereby forming a cresent-shaped space in cross-section, between the inner peripheral surface of said outer tube and the outer surface of said inner tube,

an observing optical system disposed within said inner tube;

a plurality of light guide fibers disposed within said space for transmitting light therealong;

a tip surface for emitting and receiving light, said tip surface disposed on a tip part formed by the inner and outer tubes, said tip part having an eliptical upper surface and a visual field direction forward of said tip surface;

an end portion of said inner tube disposed at the tip part, said end portion having a curved outer surface in contact with said light guide fibers;

an end portion of said outer tube disposed at the tip part, said end portion having at its lower side, diametrically opposite the upper portion of the tube, an inner curved surface in contact with said light guide fibers; and

a saddle-shaped pressing part disposed in between said inner and outer tubes at the upper portions thereof and near said tip part, said pressing part having edges for pressing said light guide fibers together in the circumferential direction with respect to said inner tube, such that said light guide fibers are concentrated in the visual field direction.

2. The hard endoscope of claim 1, wherein said end portion of said inner tube is integral with said inner tube.

3. The hard endoscope of claim 1, wherein said end portion of said outer tube is integral with said outer tube.

4. The hard endoscope of claim 1, wherein the curved surfaces of said end portions are partial parabaloids.

5. The hard endoscope of claim 1, wherein the curved surfaces of said end portions are partial spheres.

6. The hard endoscope of claim 1, wherein the outer surface of the tip part is formed by the outer peripheral surface of said end portion of said outer tube.

7. A hard endoscope, comprising:

a hard outer tube having an inner peripheral surface;

an inner tube disposed eccentrically within said outer tube such that said inner tube contacts a portion, defined as the upper portion, of said inner peripheral surface of said outer tube, thereby forming a cresent-shaped space in cross-section, between the inner peripheral surface of said outer tube and the outer surface of said inner tube,

an observing optical system disposed within said inner tube;

a plurality of light guide fibers disposed within said space for transmitting light therealong;

a tip surface for emitting and receiving light, said tip surface disposed on a tip part formed by the inner and outer tubes, said tip part having an eliptical upper surface and a visual field direction forward of said tip surface, said tip surface presenting said light guide fibers in a crescent-like shape so as to increase illumination around the observing optical system;

an end portion of said inner tube disposed at the tip part, said end portion having a curved outer surface in contact with said light guide fibers;

an end portion of said outer tube disposed at the tip part, said end portion having at its lower side, diametrically opposite the upper portion of the tube, an inner curved surface in contact with said light guide fibers; and

a saddle-shaped pressing part disposed in between said inner and outer tubes at the upper portions thereof and near said tip part, said pressing part having edges for pressing said light guide fibers together in the circumferential direction with respect to said inner tube, such that said light guide fibers are concentrated in the visual field direction.