JP2002065586A - Forward view type endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a forward view type endoscope securing constant observation window washing ability by an air-water supply nozzle and restrained from the formation of a smear caused by reflected light from a treating instrument projecting from a treating instrument projecting port. SOLUTION: A directional error of an observation optical axis 5 is constituted to allow only in a separating direction from the front side of at least one or both of the air-water supply nozzle 6 and treating instrument projecting port 7a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a forward-looking endoscope.

[0002]

2. Description of the Related Art Although an observation optical axis of a forward-looking endoscope is directed straight forward from a distal end face of an insertion portion, an actual product cannot be assembled without any error. It is allowed to incline in all directions around the center by an error within a predetermined range.

[0003]

In a forward-looking endoscope, an air supply / water supply nozzle is often arranged alongside an observation window, and the observation window and the air supply / water supply function in cleaning the observation window surface. It is desirable that the nozzle is close to the nozzle.

However, since it is not uncommon for recent forward-looking endoscopes to have a wide viewing angle of about 120 ° to 150 °, the observation optical axis is inclined toward the air / water nozzle within an allowable error range. Even in order to prevent the air / water nozzle from entering the visual field range, the distance between the observation window and the air / water nozzle must be considerably large, and as a result, the observation window cleaning ability is reduced. I will.

[0005] Further, when illumination light is reflected by a treatment tool projected from a treatment tool outlet arranged alongside the observation window, the reflected light tends to enter the observation window, thereby deteriorating the observation image quality. So-called smear may occur.

Therefore, the present invention provides a front-view type in which a certain observation window cleaning ability can be ensured by the air / water supply nozzle, and smear due to reflected light from the treatment tool projected from the treatment tool outlet is less likely to occur. It is intended to provide an endoscope.

[0007]

In order to achieve the above object, a forward-looking endoscope according to the present invention includes a front end face of an insertion portion, which is provided with an at least one of an air supply / water supply nozzle and a treatment tool outlet. In a forward-looking endoscope in which an observation window whose optical axis is directed toward the front of the insertion section is arranged, the directional error of the observation optical axis is limited only in a direction away from the front of at least one of the air / water nozzle and the treatment tool outlet. It was taken.

If the directional error of the observation optical axis is determined only in the direction away from the front of both the air / water nozzle and the treatment tool outlet, it is possible to ensure a constant observation window cleaning performance by the air / water nozzle and to ensure that the treatment tool The effect is obtained in both prevention of generation of smear due to the reflected light from the treatment tool protruding from the protrusion port.

[0009]

Embodiments of the present invention will be described with reference to the drawings. FIG. 3 shows the distal end surface 1 of the insertion section 1 of the forward-looking endoscope.
The air supply / water supply nozzle 6, the treatment tool protrusion 7 a, the illumination window 8, and the like are arranged alongside the observation window 2.

FIG. 1 shows a cross section taken along the line II in FIG. 3 including the observation window 2 and the air / water nozzle 6. The air / water nozzle 6 is inserted so as to open toward the surface of the observation window 2. It protrudes from the distal end surface 1 a of the part 1.

An objective optical system 3 supported by a lens frame 31 is disposed inside the observation window 2, and an image pickup surface of the solid-state image pickup device 4 is disposed at a position where an image of a subject is formed by the objective optical system 3. . However, an image guide fiber bundle may be arranged instead of the solid-state imaging device 4.

The observation optical axis 5 of the endoscope observation image formed on the imaging surface of the solid-state imaging device 4 by the objective optical system 3 is directed straight forward from the center of the observation window 2 by design. It is inevitable that a certain degree of inclination (direction error) occurs due to the unavoidable variation in the relative positional relationship between the objective optical system 3, the lens frame 31, and the solid-state imaging device 4.

Therefore, when assembling this part, it is set so that the inclination of the observation optical axis 5 due to the direction error occurs only in the direction away from the front of the air / water supply nozzle 6.
In the setting method, any one of the objective optical system 3, the lens frame 31, and the solid-state imaging device 4 may be adjusted as a reference.

Therefore, the visual field range does not swing toward the air / water nozzle 6 due to the design setting, so that the distance A between the observation window 2 and the air / water nozzle 6 is set by the air / water nozzle 6 by design. It can be set to the shortest distance as far as it does not fall within the visual field range, and it is possible to secure a constant observation window cleaning ability by the air / water supply nozzle 6.

FIG. 2 shows a section II-II in FIG. 3 including the observation window 2 and the treatment tool outlet 7a, and 7 is a treatment tool insertion passage. As shown in this cross section, the inclination of the observation optical axis 5 due to the directional error is set so as to occur only in a direction away from the front of the treatment tool outlet 7a.

Therefore, the visual field range does not swing toward the treatment tool outlet 7a side due to the design setting, so that the treatment tool outlet 7a
Smear due to the reflected light from the treatment tool protruding from the surface hardly occurs.

The present invention is not limited to the above embodiment. For example, the inclination of the observation optical axis 5 due to a directional error is at least one of the front of the air / water nozzle 6 and the front of the treatment tool outlet 7a. If it is set to occur in a direction away from the camera, individual effects can be obtained accordingly.

[0018]

According to the present invention, the directional error of the observation optical axis is determined only in the direction away from the front of at least one or both of the air supply / water supply nozzle and the treatment tool outlet, so that the air supply / water supply nozzle can maintain a constant error. The cleaning ability of the observation window can be ensured, and smear due to the reflected light from the treatment tool projected from the treatment tool outlet is less likely to occur, and a good endoscope observation image can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along line II in FIG. 3 of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG. 3 of the embodiment of the present invention.

FIG. 3 is a front view of a distal end surface of an insertion portion of the forward-looking endoscope according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insertion part 1a Tip surface 2 Observation window 3 Objective optical system 4 Solid-state image sensor 5 Observation optical axis 6 Air / water supply nozzle 7 Treatment tool insertion path 7a Treatment tool protrusion 31 Lens frame

Claims (2)

[Claims] 1. A forward-looking endoscope in which at least one of an air / water nozzle and a treatment tool outlet is provided on a distal end surface of an insertion portion, and an observation window whose observation optical axis faces forward of the insertion portion. A front-view endoscope, wherein the directional error of the observation optical axis is determined only in a direction away from the front of at least one of the air / water nozzle and the treatment tool protrusion. 2. A front-view endoscope in which an air supply / water supply nozzle, a treatment tool outlet, and an observation window whose observation optical axis is directed to the front of the insertion section are arranged on the distal end surface of the insertion section. A forward-looking endoscope, wherein the directional error of the observation optical axis is determined only in a direction away from the front of both the air / water nozzle and the treatment tool outlet.