JP2013192798A - Endoscope system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an endoscope system in which an observable range of an observation object is not narrowed by a hood when the hood is mounted on a distal end part of an insertion part.SOLUTION: An endoscope system includes: an endoscope 10 which is provided with an observation optical system 19 whose optical axis is eccentric to the center point 18 of a distal end face on the distal end face 17 of an insertion part 12, and provided, inside the insertion part, with an imaging element 21 for which the center of an imaging surface 22 forming a rectangle is positioned on the optical axis and the midpoint of a pair of long sides of the rectangle is positioned on one straight line extending in a radial direction from the center point when viewed in the optical axis direction; and a cylindrical hood 25 which is attachable and detachable to/from the distal end part of the insertion part and has an annular projection part 28. A distance in the straight line direction from the center point to the midpoint of one long side is longer than a distance in the straight line direction from the center point to the midpoint of the other long side, and the annular projection part is turned to such a shape that it is positioned outside of the observation field of the observation optical system when the hood is mounted on the distal end part of the insertion part.

Description

  The present invention relates to an endoscope and an endoscope system including a hood that can be attached to and detached from a distal end portion of an insertion portion of the endoscope.

In general, an endoscope includes an operation unit and a flexible insertion unit extending forward from the operation unit, and an observation optical system (objective lens) having a zooming function on the distal end surface of the insertion unit. ), And an image pickup element located immediately after the observation optical system is provided in the vicinity of the distal end of the insertion portion.
Since the endoscope is connected to a monitor via an image processing device (processor), image data (observation image) captured by the image sensor is subjected to image processing by the image processing device and displayed on the monitor.

A hood, which is a cylindrical member having both ends opened, can be attached to and detached from the distal end portion of the insertion portion of the endoscope.
When the hood is attached to the distal end of the insertion section, the positional relationship between the observation optical system and the body cavity wall is determined by pressing the distal end of the hood against the body cavity wall to be observed when the insertion section is inserted into the patient's body cavity. Can be fixed. Therefore, if the focal length of the observation optical system is increased in this state, the surgeon can perform magnified observation using a hood.

Japanese Patent No. 3686876

When the hood is attached to the distal end portion of the insertion portion, the distal end portion of the hood is positioned in front of the distal end surface of the insertion portion. Therefore, the distal end portion of the hood is picked up by the image sensor as an observation image that has passed through the observation optical system, so that the hood is projected on the monitor together with the body cavity wall.
However, when the hood is reflected on the monitor, the observable range of the body cavity wall is narrowed by the hood (the front end portion), and thus it becomes difficult to observe the body cavity wall and treat the affected part.

  An object of the present invention is to provide an endoscope system in which the observable range of an observation target is not narrowed by the hood when the hood is attached to the distal end portion of the insertion portion.

  The endoscope system of the present invention is provided with an observation optical system on the distal end surface of the insertion portion, which is a rotationally symmetric body centered on its own optical axis, and the optical axis is decentered with respect to the center point of the distal end surface, A straight line in which the center of the rectangular imaging surface is located on the optical axis, and the central point of the pair of long sides of the rectangle extends in the radial direction from the central point when viewed in the optical axis direction. An endoscope provided with an imaging element positioned above in the insertion portion, and an annular protrusion that is detachable from the distal end portion of the insertion portion of the endoscope and that is positioned on the observation object side from the distal end surface when attached. A linear hood from the center point to the center point of one of the long sides, the linear direction distance from the center point to the center point of the other long side. In the endoscope system longer than the distance, the annular projecting portion and the hood are inserted into the insertion portion. It is characterized in that it has a shape which is located in the observation field of view outside of the observation optical system when mounted on the tip.

  The portion of the annular protrusion that protrudes from the distal end surface to the observation target side of each of the following parts is opposed to the one long side in the radial direction extending from the center of the imaging element. The part facing the radial line direction extending from the center of the image sensor with respect to the other long side is B, and the corner between the one long side and the short side of the rectangle is The portion of the imaging element facing the radial line direction extending from the center is C, and the radial line direction extending from the center of the imaging element with respect to a corner portion between the other long side and the short side of the rectangle The relationship of C <D <E <A <B is established when the portion facing D is E and the portion facing the short side is E in the radial direction extending from the center of the image sensor. You may make it do.

  An indicator may be provided on the inner peripheral surface of the annular protrusion.

  According to the present invention, when the hood is attached to the distal end portion of the insertion portion, the annular protrusion is positioned outside the observation field of view of the observation optical system, so that the annular protrusion can be imaged by the imaging surface (imaging device). Absent. Therefore, since the observable range of the observation target (for example, the body cavity wall) is not narrowed by the hood, it is possible to reliably observe the observation target.

  According to the invention of claim 2, according to each area of the imaging surface (according to the amount of reflection of the hood in each area when a conventional hood is attached), the portion facing each area of the annular protrusion Therefore, the entire annular protrusion is not shortened more than necessary. Therefore, when the distal end portion of the hood is pressed against the body cavity wall, it is possible to ensure a sufficient distance between the distal end surface of the insertion portion and the observation target.

  According to the third aspect of the present invention, the hood can be mounted at a desired relative rotational direction position (circumferential position) with respect to the distal end portion of the endoscope.

1 is an overall view of an endoscope system when a hood is attached to a distal end portion of an insertion portion of an endoscope according to an embodiment of the present invention. It is an expansion perspective view of the tip part of an insertion part, and the hood with which the tip part was equipped. It is a schematic diagram when an image sensor is seen from the front. The figure of the center part is a front view of the front end part of the hood and the insertion part, and (i) (ii) (iii) (iv) (v) are seen in the respective alternate long and short dash lines Li, Lii, Liii, Liv, and Lv. It is the side view seen from the outer peripheral side of the front-end | tip part of the hood and insertion part. It is an enlarged front view of the front-end | tip part of a hood and an insertion part. It is a front view of the tip part of a hood and an insertion part when a hood is mounted on the tip part of an insertion part of a modification.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. In the following description, the front-rear direction (the front end side of the insertion portion 12 of the endoscope 10 is defined as “front”, and the front end side (connector portion 14 side) of the universal tube 13 is defined as “rearward”), up-down direction, And the left-right direction is based on the arrow direction in the figure.
The medical endoscope 10 is fixed to an operation part 11 made of a hard resin, an insertion part 12 extending forward from the operation part 11, a universal tube 13 extending rearward from the operation part 11, and a rear end of the universal tube 13. Connector portion 14.

  The insertion portion 12 extends forward from the operation portion 11 and has a flexible flexible tube portion 15, and is positioned in front of the flexible tube portion 15 and is used to operate a bending operation lever provided in the operation portion 11. The bending part 15a which curves according to it, and the front-end | tip hard part 16 which comprises the part located ahead from the bending part 15a are comprised. The distal end hard portion 16 is made of a hard resin material (for example, ABS, modified PPO, PSU, etc.) that is substantially inelastically deformable. On the distal end surface 17 consisting of the flat surface of the distal end hard portion 16, a through hole having a circular cross section penetrating the distal end hard portion 16 in the axial direction is formed at a position offset upward from the center point 18 of the distal end surface 17. The through-hole is provided with an observation optical system 19 composed of a plurality of lenses that are coaxial with each other. Each lens constituting the observation optical system 19 is a rotationally symmetric body with the optical axis OA of the observation optical system 19 as the center. The observation optical system 19 includes an objective lens 20 that is a front-facing circular fixed lens located at the forefront, and a movable lens group (not shown) located behind the objective lens 20. By moving in the optical axis OA direction (front-rear direction), the focal length of the observation optical system 19 changes (zooming operation is performed).

Further, an imaging element 21 located immediately after the observation optical system 19 is provided in the through hole. As shown in FIGS. 3 to 5, the front shape of the imaging surface 22 of the imaging device 21 is a rectangle, and the center 22 a of the imaging surface 22 is located on the optical axis OA of the observation optical system 19 (objective lens 20). . When the front end surface 17 is viewed from the front (when viewed in the direction of the optical axis OA of the observation optical system 19), the center points of the pair of long sides (extending in the left-right direction) of the rectangle (imaging surface 22) are both It is located on a radial straight line L (see FIG. 5) extending in the radial direction (radial direction) from the center point 18 (a pair of long sides are orthogonal to the radial straight line L). Further, the distance in the radial direction (straight direction) from the center point 18 when the front end surface 17 is viewed from the front to the center point of the long side on one side (the upper side in FIGS. 4 and 5) is from the center point 18. It is longer than the distance in the radial direction (linear direction) to the center point of the other long side (lower side in FIGS. 4 and 5).
Further, the rear end portion of an image signal cable (not shown) extending rearward from the image sensor passes through the internal space of the insertion portion 12, the operation portion 11, and the universal tube 13 and is connected to the connector portion 14.

  As shown in FIGS. 2 and 3, the distal end surface 17 has a pair of through holes penetrating the distal end hard portion 16 in the axial direction, and an illumination optical system 23 (illumination lens) is formed at the front end of each through hole. ) Are fixed (FIG. 2 shows only one illumination optical system, and the other is omitted). A pair of flexible light guide fibers (not shown) are disposed in the internal space of the insertion section 12, the operation section 11, the universal tube 13, and the connector section 14, and the front ends of the light guide fibers are Each light guide fiber is connected to each illumination optical system 23 inside the distal end hard portion 16 (through hole), and the rear end of each light guide fiber passes through the internal space of the insertion portion 12, the operation portion 11, and the universal tube 13. It is connected to the connector part 14.

When the connector unit 14 is connected to a processor (image processing device / light source device) (not shown) and the light emitted from the light source built in the processor is supplied to the rear end face of the light guide fiber in the connector unit 14, the distal end is hard. A pair of illumination optical systems 23 provided on the distal end surface 17 of the portion 16 irradiates illumination light forward.
Further, an observation image that is transmitted through the observation optical system 19 (objective lens 20) (to be observed) is picked up by the image pickup device 21. However, since the observation optical system 19 guides the photographing light beam to the image sensor 21 (imaging surface 22) while gradually reducing the light beam diameter, the outer shape of the photographing light beam on the same plane as the imaging surface 22 is indicated by a virtual line in FIG. The shape (circular shape) is formed, and the four corner portions (portions filled in black) of the imaging surface 22 do not capture the observation target (observation image). The imaging data generated by the imaging device 21 is sent to the image processing device of the processor via the image signal cable, and the image data processed by the image processing device is displayed on a monitor (not shown) connected to the processor. Is done.

The hood 25 that can be attached to and detached from the front end portion of the distal end hard portion 16 is an integrally molded product made of rubber, elastomer, or resin material, and has appropriate elasticity and hardness. The hood 25 is a cylindrical body centered on its own axis, and both front and rear ends thereof are open. The inner peripheral surface of the hood 25 is a fitting surface having a larger diameter than the inner peripheral reflective surface 26 constituting the front portion thereof and the inner peripheral reflective surface 26 constituting a portion located behind the inner peripheral reflective surface 26. 27 (see FIGS. 2 and 4). The inner peripheral reflection surface 26 has a smaller diameter than the hard tip portion 16, and the fitting surface 27 has substantially the same diameter as the hard tip portion 16. The annular protrusion 28 constituting the front portion of the hood 25 (the portion where the inner peripheral reflection surface 26 is formed) has a circular through-hole 25a (FIG. 4 (iv)) passing through the annular protrusion 28 in the thickness direction. Reference) is formed.
Concavities and convexities are formed on the tip surface of the annular protrusion 28 of the hood 25. In other words, the tip surface of the annular protrusion 28 is divided into eight regions having different shapes. That is, one first plane 29, one second plane 30, a pair of left and right third planes 31, a pair of left and right first recesses 32 positioned between the second plane 30 and the third plane 31, A pair of left and right second recesses 33 located between the first plane 29 and the third plane 31 are provided. The first plane 29, the second plane 30, and the third plane 31 are planes orthogonal to the front-rear direction (the axial direction of the hood 25), and the first plane 29 and the second plane 30 are the axes of the hood 25. They are located on opposite sides of each other (the rotational phase of both is 180 °). The concavo-convex shape of the front end surface of the hood 25 including the first plane 29, the second plane 30, the third plane 31, the first recess 32, and the second recess 33 is the center point of the first plane 29 and the second plane 30. Is symmetrical with respect to the radial straight line L (see FIG. 5) passing through the center point.
As shown in FIGS. 2, 4, and 5, the first plane 29 is (slightly) ahead of the third plane 31, and the second plane 30 is positioned ahead of the first plane 29. The first recess 32 is recessed backward from the third plane 31, and the second recess 33 is recessed backward from the first recess 32. Therefore, the forward protrusion amount (front-rear length) of the annular protrusion 28 (from the front end of the fitting surface 27) varies depending on the circumferential position. That is, the protrusion amount of the portion of the annular protrusion 28 where the first plane 29 is formed at the tip is A, the protrusion amount of the portion where the second plane 30 is formed at the tip is B, and the third plane 31 is at the tip. When the protruding amount of the formed portion is E, the protruding amount of the portion where the first recess 32 is formed at the tip is D, and the protruding amount of the portion where the second recess 33 is formed at the tip is C,
C <D <E <A <B
The relationship is established.
Further, the forward protrusion amount of the annular protrusion 28 is smaller than that of the conventional hood. That is, the hood 25 has a shape in which the annular protrusion 28 (the tip thereof) is located outside the observation field of the observation optical system 19 (objective lens 20) when the hood 25 is attached to the tip hard portion 16.

The hood 25 can be attached to the distal end hard portion 16 by approaching the distal end surface 17 from the front. At this time, the surgeon works while visually recognizing the hood 25 displayed on the monitor, and detachably attaches the hood 25 to the distal end hard portion 16 while positioning the through hole 25a at the lower end of the annular projecting portion 28. .
When the hood 25 is attached to the distal end portion of the distal end hard portion 16, the annular projecting portion 28 (inner peripheral reflection surface 26) is positioned in front of the distal end surface 17. Further, the first plane 29, the second plane 30, the third plane 31, the first recess 32, the second recess 33 and the tip surface 17 are in the positional relationship shown in FIGS. 4 and 5. That is, when viewed from the front, facing one long side (the upper side in FIGS. 4 and 5) that forms the outer shape of the imaging surface 22 (in the radial direction extending from the center 22 a of the imaging surface 22). The first flat surface 29 is located at a position where the first flat surface 29 is opposed to the other long side of the rectangle (lower side in FIGS. 4 and 5) (in the radial direction extending from the center 22 a of the imaging surface 22). The two planes 30 are located, and the imaging is performed with respect to corners (upper two corners in FIGS. 4 and 5) between the one long side of the rectangle and the short side (extending in the vertical direction) of the rectangle. A second recess 33 is located at a position facing the surface 22 in the radial line direction extending from the center 22a of the surface 22, and a corner between the other long side of the rectangle and the short side of the rectangle (lower in FIG. 4 and 5). Radial linear direction extending from the center 22a of the imaging surface 22 with respect to the two corners on the side ) First recess 32 is located in a position opposed to (in the radial-line direction extending from the center 22a of the imaging surface 22 with respect to the short side of the rectangle) third plane 31 at opposite positions is located.

  When the insertion portion 12 to which the hood 25 is attached is inserted into the body cavity of a patient (not shown) and the front end surface of the hood 25 is pressed against the body cavity wall where the affected portion is located, the affected portion and the objective lens 20 (in the optical axis OA direction) The spacing is kept constant. Further, a part of the illumination light emitted from the illumination optical system 23 directly illuminates the affected part (body cavity wall), and after the remaining illumination light is reflected by the inner peripheral reflecting surface 26, the affected part (body cavity wall) is illuminated. Accordingly, the surgeon can perform magnified observation using the hood 25 by operating the zoom operation means provided in the operation unit 11 in this state to increase the focal length of the observation optical system 19.

  Then, as described above, the amount of forward protrusion of the annular protrusion 28 is made smaller than that of the conventional hood, so that when the hood 25 is mounted on the distal end hard part 16, the annular protrusion 28 (the distal end thereof) is observed optically. Since the system 19 (objective lens 20) is positioned outside the observation field of view, the annular protrusion 28 (the tip thereof) is imaged by the imaging surface 22 and is not displayed on the monitor (the conventional hood is attached to the tip hard part). In the case of being attached to 16, the tip of the hood is imaged by the imaging surface 22 as indicated by the phantom line in FIG. 3, and the tip of the hood is displayed on the monitor). Therefore, since the observable range of the body cavity wall is not narrowed by the hood 25 (annular protrusion 28), the operator can reliably observe the body cavity wall and treat the affected part.

Furthermore, the hood 25 of this embodiment can also exhibit the effects described below.
As shown in FIG. 3, the imaging range of the hood by the imaging surface 22 when a conventional hood is mounted on the distal end hard portion 16 varies depending on the position of the imaging surface 22. Specifically, a portion (area Ac) positioned on a straight line extending from the center 22a (optical axis OA) of the imaging surface 22 to one (upper side in FIG. 3) corner, the center 22a (optical axis OA) of the imaging surface 22 ) To the other (lower side in FIG. 3) portion located on a straight line (area Ad), a portion located on a straight line extending from the center 22a (optical axis OA) of the imaging surface 22 to the short side of the rectangle (Area Ae), a portion (area Aa) located on a straight line extending from the center 22a (optical axis OA) of the imaging surface 22 to one long side (upper side in FIG. 3), the center 22a (optical axis OA) of the imaging surface 22 ) To the other (lower side in FIG. 3) in the order of the portion (area Ab) located on the straight line extending from the long side (the image is reflected most in area Ac and the image reflected in area Ab is the smallest).
For example, even when the annular protrusion 28 of the hood is cut along a plane that is located on the center portion (the portion that is most greatly recessed rearward) of the second recess 33 and is orthogonal to the optical axis OA, The image is not captured by the imaging surface 22 (not displayed on the monitor). However, in this case, since the longitudinal length of the entire annular protrusion of the hood is shortened, a sufficient distance cannot be secured between the distal end surface 17 and the body cavity wall when the distal end of the hood is pressed against the body cavity wall.
On the other hand, the hood 25 of the present embodiment corresponds to each area Ac, Ab, Ac, Ad, Ae on the imaging surface 22 (each area Ac, Ab, Ac, Ad, Ae when a conventional hood is attached). The amount of protrusion of the portion of the annular protrusion 28 facing the areas Ac, Ab, Ac, Ad, and Ae is changed so that the entire annular protrusion 28 is more than necessary. It does not become shorter (the second plane 30 facing the area Ab and the first plane 29 facing the area Aa have substantially the same longitudinal length as the conventional hood). Therefore, it is possible to ensure a sufficient distance between the distal end surface 17 and the body cavity wall when the distal end portion of the hood 25 is pressed against the body cavity wall.

As mentioned above, although this invention was demonstrated using the said embodiment, this invention can be implemented, giving various deformation | transformation.
In the present invention, an observation optical system 19 that is a rotationally symmetric body about its own optical axis is provided after being decentered with respect to the center point of the tip surface 17, and the center of the rectangular imaging surface 22 is the observation optical system. An image pickup device that is located on 19 optical axes OA and that is located on a straight line in which the center point of the pair of long sides of the rectangular shape extends in the radial direction from the center point when viewed in the direction of the optical axis OA. In addition, the linear distance from the central point to the central point of one of the long sides is longer than the linear distance from the central point to the central point of the other long side. Applicable to mirrors. Therefore, if the endoscope satisfies this requirement, the present invention can also be applied to an endoscope in which the attachment positions of the observation optical system 19 and the imaging element 21 with respect to the distal end surface 17 are different from those in the above embodiment.
FIG. 6 shows an example. In this modification, the attachment positions of the observation optical system 19 and the image pickup device 21 with respect to the distal end surface 17 are 90 ° (counterclockwise in front view) as compared with the endoscope 10 of the above embodiment. It has been rotated. Therefore, the hood 25 is attached to the distal end hard portion 16 after being rotated by 90 ° (counterclockwise in a front view) as compared to the case of the above embodiment.

  Moreover, you may form the parameter | index of the shape different from the through-hole 25a in the hood 25 (for example, the parameter | index consisting of a figure etc. may be printed on the internal peripheral surface of the cyclic | annular protrusion part 28, or the outer peripheral surface of the hood 25).

DESCRIPTION OF SYMBOLS 10 Endoscope 11 Operation part 12 Insertion part 13 Universal tube 14 Connector part 15 Flexible tube part 16 Tip rigid part 17 Tip surface 18 Center point 19 of the tip surface Observation optical system 20 Objective lens 21 Imaging element 22 Imaging surface 22a Imaging surface Center 23 Illumination optics (illumination lens)
25 Hood 25a Through hole (index)
26 Inner peripheral reflection surface 27 Fitting surface 28 Annular protrusion 29 First plane 30 Second plane 31 Third plane 32 First recess 33 Second recess OA Optical axis of observation optical system

Claims (3)

The distal end surface of the insertion portion is provided with an observation optical system that is a rotationally symmetric body centered on its own optical axis and whose optical axis is decentered with respect to the center point of the distal end surface, and the center of the imaging surface forming a rectangle is the above Inserting the image pickup device located on the optical axis and having a central point of the pair of long sides of the rectangle on a straight line extending in the radial direction from the central point when viewed in the optical axis direction An endoscope provided in the department;
A cylindrical hood having an annular protrusion that is detachable from the distal end of the insertion portion of the endoscope and is positioned closer to the observation object than the distal end surface when attached;
With
In the endoscope system, the distance in the linear direction from the center point to the center point of one of the long sides is longer than the distance in the linear direction from the center point to the center point of the other long side.
An endoscope system according to claim 1, wherein the annular protrusion has a shape that is positioned outside the observation field of view of the observation optical system when the hood is attached to the distal end of the insertion portion. The endoscope system according to claim 1, wherein
The amount of protrusion from the tip surface of each of the following parts of the annular protrusion to the observation target side is as follows:
A portion facing the radial line direction extending from the center of the image sensor with respect to the one long side is A,
The part facing the radial direction extending from the center of the image sensor with respect to the other long side is B,
The part facing the radial linear direction extending from the center of the imaging element is C, with respect to the corner portion between the one long side and the short side of the rectangle.
The portion facing the radial straight direction extending from the center of the imaging element is D, with respect to the corner portion between the other long side and the short side of the rectangle.
A portion facing the short side in the radial direction extending from the center of the image sensor is E,
When
C <D <E <A <B
Endoscope system where the relationship is established. The endoscope system according to claim 1 or 2,
An endoscope system in which an index is provided on the inner peripheral surface of the annular protrusion.

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