JPH0218514A - Endoscope device - Google Patents

Abstract

PURPOSE:To obtain an in-focus enlarged image automatically by moving an optical member according to the movement distance of an image pickup element and correcting a focusing distance when the image pickup element is moved so as to obtain the enlarged observation image. CONSTITUTION:An optical system unit 6 provided with an objective 3, etc., is provided in a scope tip part 1 while projected from the tip end surface. Further, the image pickup element 8 is pressed forward by a spring 17 and drawn backward by a wire 16. A gear 18 with a pulley is fitted atop the wire, the gear 18 engages a gear 19 which is movable in the direction of the optical axis, and a wire 20 which presses the optical system unit and never buckles is coupled with the gear 19. Therefore, when the image pickup element 18 is moved backward so as to obtain the enlarged image, the unit 6 moves forward through the wire 20 according to the distance and the in-focus enlarged image can be observed automatically.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Field of Application) The present invention relates to an endoscope device that can obtain an enlarged image of an observation region, and in particular, to an endoscope device that can obtain an enlarged image of an observation region. The present invention relates to an endoscope having a mechanism for correcting a change in focusing distance in response to movement when the endoscope moves.

(Prior technology) Currently, there are two types of endoscopes available: fiberscope type and electronic endoscope type. Some are provided with a variable rate function.

In this endoscope, like other endoscopes, an observation site 2 in the body cavity to be targeted for shooting is illuminated from a scope tip 1 through a light guide, and the reflected light is sent to an objective lens 3 provided at the scope tip 1. The light is collected by optical system members such as the above, and is received by the glass fiber east end face 4 and the like.

When observing without commanding such magnification, the distance is approximately the specified distance from the observation site 2! The distal end portion 1 of the scope is held at a position one distance away from the user to obtain a focused observation image.

On the other hand, when commanding the enlargement of the observation image from this state, the 31st D
As shown in (b), the glass fin Nl east end face 4 is retracted in the longitudinal direction of the scope. Due to this retreat, the distance between the glass fiber east end surface 4 and the objective lens 3 attached to the scope tip 1 changes, and with this distance change, the observation region 2 and the objective lens when the glass fiber bundle end surface 4 is in focus change. Since the distance to the lens 3 (hereinafter referred to as focusing distance) changes from 2 to 2□, this focusing distance must be corrected.

(Problem to be Solved by the Invention) However, such scopes are not equipped with a mechanism for correcting the change in focusing distance as described above, and therefore, the operator is forced to adjust the shortened focusing distance. distance! 2, it is necessary to move the scope distal end 1 back and forth with respect to the observation site 2 while looking at the observation image of the endoscope to find the position that is best in focus. Furthermore, when the magnification ratio is set to a large value, it is easy to lose sight of the observation area 2, which is the sniping target, because the stomach wall and the like in the body cavity are constantly moving, making adjustment difficult and cumbersome.

The present invention has been made in view of the problems of the prior art, and an object of the present invention is to provide an endoscope that can automatically observe a focused image when obtaining a magnified observation image. That is.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, in the endoscope according to the present invention, the light-receiving surface that receives the illumination reflected light from the observation site that is focused by the optical system member is positioned along its optical axis. a light-receiving surface moving mechanism that moves the light-receiving surface along the direction of the light-receiving surface; and a focusing distance setting that moves the optical system member to give the optical system member a focusing distance corresponding to the distance from the moved light-receiving surface to the optical system member. The device is equipped with a mechanism.

(Function) According to the above configuration, when transitioning from the normal observation state in which the distal end of the scope is observed at a focusing distance from the observation site and obtaining a magnified observation image, the light receiving surface moving mechanism moves the light receiving surface to the optical axis. At the same time, the optical system members are moved along the optical axis so that the distance between the observation area and the light-receiving surface becomes a focusing distance that changes depending on the movement of the light-receiving surface. Enlarged images can be observed. Further, even when transitioning from this state to normal magnification observation, the operation opposite to the above is performed and the focus does not shift.

(Example) Hereinafter, an example in which the present invention is applied to an electronic endoscope will be described.
This will be explained with reference to FIG. 1 or 2. In FIGS. 1 and 2, parts that are the same or equivalent to those of the conventional example shown in FIG. 3 are designated by the same reference numerals.

In FIG. 1, an optical system unit 6 that can protrude from the distal end face is provided inside the scope distal end 1. As shown in FIG. Inside the optical system unit 6, an optical system including a light guide section 7 that emits illumination light from the optical system unit 6, and a plurality of objective lenses 3, etc., into which light reflected from the observation region 2 due to this illumination is incident. An image pickup device 8 such as a CCD that receives an optical image focused by the objective lens 3 is provided.

The light guide section 7 is provided at two opposing positions around the objective lens 3, and includes a fiber bundle 11 that guides light from a light source, and a fiber bundle 11 that fixes the fiber bundle 11 and extends from the end of the fiber bundle 11 at a predetermined position. Lens 1 at the distance layer position
2, and a lens 14 located in front of the lens 12 and attached to the optical system unit 6. The guide 13 is provided slidably within the optical system unit 6.

Further, the plurality of objective lenses 3 are attached to the tip of the central portion of the optical system unit 6.

Further, the image pickup device 8 is provided behind the objective lens 3 so as to be movable along the optical axis while the image pickup surface 8a is held perpendicular to the optical axis direction. This image sensor 8 is subjected to a tensile force backward on the optical axis by a wire 16, and a spring 17 provided between the image sensor 8 and the optical system unit 6 is applied to the image sensor 8, which is weaker than the tensile force of the wire 16. It is being pushed forward on the optical axis. The pulling side end of the wire 16 is rotatably attached to a pulley of a gear with a boot 18 provided behind the optical system unit 6 so as to be movable along the optical axis. Rank 1 with this pulley
The rotation amount of 8 is controlled by an enlargement operation knob 23, which will be described later. A gear 19 that is movable in the optical axis direction is meshed with the gear 18 with the boob. This gear 19 and the optical system unit 6 are connected to each other using a wire 20 that does not buckle.
connected with.

Therefore, simultaneously with the movement of the image sensor 8, the optical system unit 6 protrudes from the scope tip 1 and moves forward toward the observation site 2. The distance between the image sensor 8 and the objective lens 3 changes as the image sensor 8 moves along the optical axis, and the focusing distance changes with this change. The relationship between the pulley gear 18 and the rack 19 and the wire 16 .
This is set based on the length of 20, etc.

Note that a gear with a pulley 18. Rack 19. It goes without saying that the mechanism is not limited to the one that uses the wires 16 and 20.

Moreover, the scope tip 1 of such an optical system unit 6
Sufficient treatment is required to prevent water from entering the portion between the optical system unit 6 and the distal end portion 1 of the scope as well as the portion protruding from the scope.

On the other hand, as shown in FIG. 2, an operating section is provided at one end of the guide section 21 which has the scope distal end 1 as described above and is inserted into a body cavity, and has the function of performing various operations on the guide section 21. 22 are provided. This operation section 22 is provided with the aforementioned enlargement operation knob 23.

Next, the operation of this embodiment will be explained.

The operator inserts the guiding part 21 into the body cavity of the subject, positions the scope tip 1 at a focusing distance of about 2 to 3 C11 from the wall surface such as the stomach wall to be observed, and observes the observed image on a CRT or the like. While doing so, aim at a specific observation area 2. During this time, the light guided by the fiber bundle 11 is converted into square light by the lens 12, then converted into scattered light by the lens 14, and is emitted toward the observation site 2.

Next, the enlargement operation knob 23 is operated to instruct enlargement of the observed image. This command drives and rotates the gear with a pulley 18, and this rotation causes the image sensor 8 to retreat along the optical axis. At the same time as this retraction, as the gear with pulley 18 rotates, a predetermined proportion of the retraction distance of the image sensor 8 is moved to rank 19.
moves forward, and the optical system unit 6 moves to the front end of the scope 1.
It protrudes from and slides in line with the observation area 2. That is, as the image sensor 8 moves, the optical system unit 6 is moved by a focusing distance shorter than the movement of the image sensor 8, thereby correcting the change in the focusing distance. Further, the fiber bundle 11 and the lens 12 are connected to the optical system unit 6 by the kite 13.
Slide it toward the tip.

Therefore, when a command is given to obtain an enlarged image after adjusting to the normal focusing distance, the optical image of the observation region 4 is incident on the imaging device 1 in a focused state without the need for troublesome focusing. An enlarged image can be observed with the observation region 4 captured.

In the above embodiment, the optical system unit 6 includes a light guide section 7. Objective lens 3. Although the image pickup device 8 and the like are housed in the optical system unit 6, a tube for a forceps opening, a tube for air supply, a water supply, etc. may be incorporated into the optical system unit 6.

[Effect of the invention] As explained above, in the endoscope according to the present invention,
When attempting to obtain a magnified observation image from the normal observation state in which the tip of the scope is observed at a focusing distance from the observation site, the light receiving surface movement mechanism moves the light receiving surface along the optical axis and Since the optical system members are moved so that the focusing distance changes with the movement of the surface, an enlarged image that is automatically in focus can be observed.

[Brief explanation of the drawing]

FIG. 1 is an explanatory longitudinal cross-sectional view of the distal end portion of an endoscope according to an embodiment of the present invention, and FIG. 2 is a partial external view of the endoscope according to the present embodiment.
FIG. 3 is an explanatory longitudinal cross-sectional view showing an example of a conventional endoscope tip. ■... Scope tip 3... Objective lens 6.
...Optical system unit 7...Light guide section 8.
...Non-life insurance element 23...Enlargement operation nof ■ Fig. 2 Fig. 3 (b)

Claims (1)

[Claims] (1) A light-receiving surface moving mechanism that moves a light-receiving surface that receives illumination reflected light from an observation site that is focused by an optical system member along its optical axis, and a light-receiving surface moving mechanism that moves a light-receiving surface that receives illumination reflected light from an observation site that is focused by an optical system member, and a An endoscope apparatus comprising: a focusing distance setting mechanism that moves the optical system member in order to give the optical system member a focusing distance corresponding to the distance.