JPH08553A - Electronic endoscope - Google Patents

Abstract

PURPOSE:To maintain the smaller diameter of a front end and to shorten the min. visible distance of pincers without diminishing an illumination window. CONSTITUTION:A solid-state image pickup element 23 is formed to a rectangular shape slender in the central axial direction of an objective lens 19 to widely assure the space for the illumination windows arranged on both right and left sides of an optical element consisting of the objective lens 19 and a prism 21 and to widen the angle of view of a vertical direction in the case of downward positioning of a pincer port from which a treatment means arranged on the side opposite to the solid-state image pickup element 23 with respect to the optical system element projects.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical electronic endoscope for imaging the inside of a human body, for example.

[0002]

2. Description of the Related Art Recent electronic endoscopes are required to use as many pixels as possible on a solid-state image pickup device arranged in an extremely narrow and limited space in order to cope with high image quality. Therefore, the element of the optical system arranged in front of the solid-state image pickup element has the same size as the solid-state image pickup element. Further, an image produced by these is displayed using the largest possible area of a horizontally long monitor screen similar to that used in a normal television or the like.

FIG. 7 is a schematic overall configuration diagram of such a conventional electronic endoscope. In this electronic endoscope, the scope 1 is connected to the processor body 3, and a CRT display 5 serving as a monitor screen is installed on the processor body 3. The scope 1 in FIG. 7 is an enlarged view of the main parts of the respective parts incorporated in the distal end portion. The built-in parts include the objective lens 7, the prism 9, and the substrate 1.
There is a solid-state image sensor (CCD) 13 mounted on the device 1.

The light introduced from the objective lens 7 arranged at the tip of the scope 1 is reflected by the reflecting surface of the prism 9 and then received by the light receiving surface of the CCD 13, where the photoelectrically converted electrical signal is the processor body. 3, the processor main body 3 converts the input electric signal into a signal that can be displayed on the display 5.

Normally, the size of the display screen of the display 5 is a horizontally long size which is slightly longer in the horizontal direction than the vertical direction. It has a rectangular shape that is long in the lateral direction (the arrow X direction in FIG. 7) when viewed from the front of the tip. The conductive connecting portion 11a such as a signal line connected to the CCD 13 is arranged at the end of the CCD 13 on the long side.

FIG. 8 is a diagram showing the arrangement of the respective parts as seen from the front of the tip of the scope 1. The forceps port 15 is opened on the lower side of the optical system element consisting of the objective lens 7 and the prism 9, and the optical system is shown. Illumination windows 17 are formed on both left and right sides of the element. The forceps opening 15 is a portion through which a treatment tool used for performing an appropriate treatment on a predetermined part of the human body is projected, and the illumination window 17 receives the illumination light guided by an illumination light transmission mechanism such as an optical fiber. It is for irradiating the imaging unit.

[0007]

By the way, in the electronic endoscope as described above, the scope 1 is desired to have a small diameter, but the CC arranged in a laterally long state is desired.
Since the illumination light transmission mechanism connected to the illumination window is arranged on both the left and right sides of the prism 9 having a size corresponding to D13, the diameter of the illumination window 17 becomes smaller as the diameter becomes smaller, and the illuminance is lowered to be clear. There is a risk that a good image will not be obtained.

Further, the treatment tool protruding from the forceps port 15 is
The image is taken by the CCD 13, but if the CCD 13 is arranged in a laterally long state, the distance (minimum forceps visible distance) from the distal end surface of the scope to the position where the treatment tool is projected in the protruding process becomes long, The operability when using the treatment tool is poor, and improvement has been desired.

Therefore, an object of the present invention is to maintain the thinning of the tip portion and shorten the minimum forceps visible distance without reducing the size of the illumination window.

[0010]

In order to achieve the above-mentioned object, the present invention provides a light introducing surface portion for introducing external light and a light introduced from the light introducing surface portion in a central axis direction of the light introducing surface portion. A reflection surface portion for reflecting in a substantially vertical direction, and light receiving the light reflected by the reflection surface portion, having a solid-state image sensor having a rectangular light receiving surface substantially parallel to the central axis of the light introduction surface portion, Illumination windows for irradiating the imaged region are formed on both the left and right sides of the optical system element including the light introducing surface section and the reflecting surface section, and the imaged area is formed on the opposite side of the optical system element from the solid-state image sensor In the electronic endoscope in which a forceps opening through which a treatment tool for performing an appropriate treatment is projected on a part, the shape of the solid-state imaging device is long along the central axis direction of the light introduction surface portion, and A rectangle with a short direction connecting the lighting windows Was there as a constituent.

[0011]

According to the electronic endoscope having such a structure, the solid-state image pickup device has a short length in the direction connecting the left and right illumination windows, and accordingly, the size of the optical system device in the same direction is reduced. Therefore, the diameter reduction of the tip portion is maintained without reducing the size of the illumination windows arranged on the left and right sides of the optical system element. Further, since the solid-state imaging device has a shape that is long along the central axis direction of the light introduction surface portion, the vertical angle of view becomes large, and the minimum visible forceps distance of the treatment tool protruding from the forceps port becomes short.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic perspective view showing an essential part of the internal structure of the tip of a scope in an electronic endoscope showing an embodiment of the present invention. Light introduction surface 19a at the tip of the scope
A prism 21 is arranged behind the objective lens 19 having the. The prism 21 includes a reflecting surface portion 21 a that reflects the light introduced from the objective lens 19 in a direction perpendicular to the central axis direction of the objective lens 19.

A solid-state image sensor (CCD) 23 is mounted on a substrate 25 above the prism 21 in FIG. 1, which is the direction in which the light reflected by the reflecting surface portion 21a travels. The light receiving surface 23a of the CCD 23 has a rectangular shape that is long along the central axis direction of the objective lens 19.
The end of the substrate 25 on the longitudinal side of the CCD 23 is the CCD 2
A conductive connecting portion 25a is formed so as to project from 3, and a cable 27 is connected to the conductive connecting portion 25a.

FIG. 2 is a view showing the arrangement of each part of the electronic endoscope as seen from the front of the distal end of the scope. As in the prior art example shown in FIG. 8, it comprises an objective lens 19 and a prism 21. A forceps port 29 is provided on the lower side of the optical system element.
And an illumination window 31 is formed on both left and right sides of the optical system element. The prism 21 is the CCD 23
The shape is short in the left-right direction and long in the up-down direction according to the shape.

According to the electronic endoscope having such a structure, as shown in FIG. 2, the dimension of the prism 21 is short in the left-right direction in accordance with the CCD 23 having a short dimension in the left-right direction. The illumination windows 31 arranged on both the left and right sides of the optical system element consisting of 19 can be formed larger when the scope diameter is the same as in the conventional example of FIG. Therefore, even if the diameter of the scope is reduced, the illumination window 31 does not become small unlike the conventional case, and the illuminance of the illumination light is maintained as desired.

Further, the CCD 23 is short in the left-right direction in FIG. 2, and the conducting connection portions 25a are provided at both ends in the longitudinal direction of the CCD 23 (direction orthogonal to the paper surface in FIG. 2). The CCD 23 can be brought closer to the outer peripheral side of the endoscope as compared with the conventional one, and the layout of each part in the scope such as the arrangement of the prism 21 which is long in the vertical direction is facilitated.

FIG. 3 shows the path of light in the optical system element,
The present example (shown by a solid line) and the conventional example (shown by a broken line) are shown in comparison with each other. (A) is a side view, (b) is a top view,
(C) is a front view. According to this, the reflecting surface portion 21a of the prism 21 has a long CC in the left-right direction in FIG.
Due to the shape of D23, the present embodiment is formed larger than the conventional example.

FIG. 4 shows a comparison of the minimum forceps visible distance from the distal end surface S of the scope between this embodiment (illustrated by the solid line) and the conventional example (illustrated by the broken line). In the case of the present embodiment, as described above, since the reflecting surface portion 21a of the prism 21 is large, the vertical angle of view α is larger than the conventional angle of view β, and the forceps port is accordingly increased. The minimum forceps visible distance A at which the treatment tool protruding from 29 can be confirmed on the monitor screen is shorter than the same distance B of the conventional example. By shortening the minimum forceps visible distance A, the position projected on the monitor screen of the treatment instrument protruding from the forceps port 29 becomes closer to the scope distal end surface S, and the operability when using the treatment instrument is improved. To do.

FIG. 5 shows an example in which the scope 33 having the CCD 23 as described above is connected to a processor main body 37 having a CRT display 35 serving as a monitor screen on the top. In this case, the CRT display 35
The screen shape is made vertically long in accordance with the shape of the CCD 23 so that an image corresponding to the vertically widened view angle α can be projected. In the case of this example, the reading direction of the image on the CCD 23 is the horizontal direction along the short side of the rectangular light receiving surface 23a as indicated by the arrow P, and the scanning line direction on the display 35 is also indicated by the arrow Q accordingly. Horizontally along the short side of the screen.

In contrast to the example shown in FIG. 5, FIG.
The reading direction of 3 is the vertical direction along the long side of the light receiving surface 23a indicated by the arrow R, and the scanning line direction in the display 35 is also the vertical direction along the long side of the screen in accordance with this.

In the case of FIG. 5 described above, the scanning line direction of the display 35 is the same as the conventional one, and the reading direction of the CCD 23 may be changed from the conventional one. On the other hand, in the case of FIG. 6, the reading direction of the CCD 23 is the same as the conventional one, and the scanning line direction of the display 35 may be changed from the conventional one.

[0023]

As described above, according to the present invention, the solid-state image pickup element has a short length in the direction connecting the illumination windows arranged on both left and right sides of the optical system element, and the solid-state image pickup element conforms to this shape. As a result, the dimension of the optical system element in the direction in which the illumination windows are connected to each other is reduced, and the diameter of the tip portion can be kept small without reducing the illumination window. Further, since the solid-state imaging device is long along the central axis direction of the light introduction surface portion, it is possible to shorten the minimum visible forceps distance that can be imaged by the treatment tool protruding from the forceps opening.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing a main part of an internal structure of a distal end of a scope in an electronic endoscope showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing the arrangement of each part as seen from the front of the distal end of the scope of FIG.

FIG. 3 is an explanatory diagram showing a path of light in an optical system element in comparison between a present example (illustrated by a solid line) and a conventional example (illustrated by a broken line).

FIG. 4 is an explanatory diagram showing the minimum visible forceps distance from the distal end surface of the scope in comparison between the present embodiment (illustrated by a solid line) and the conventional example (illustrated by a broken line).

5 is an overall configuration diagram showing an example of a combination of a CCD reading direction and a display scanning line direction in the electronic endoscope of FIG.

FIG. 6 is an overall configuration diagram showing another example of a combination of the reading direction of the CCD and the scanning line direction of the display.

FIG. 7 is an overall configuration diagram of an electronic endoscope showing a conventional example.

8 is an explanatory view showing the arrangement of each part as seen from the front of the distal end of the scope of FIG. 7. FIG.

[Explanation of symbols]

 19a Light introduction surface part 21a Reflective surface part 23 Solid-state image sensor 23a Light receiving surface 29 Forceps mouth 31 Illumination window

Claims (5)

[Claims] 1. A light introducing surface portion for introducing external light, a reflecting surface portion for reflecting the light introduced from the light introducing surface portion in a direction substantially perpendicular to a central axis direction of the light introducing surface portion, and a reflection surface portion for reflecting the light. And a solid-state imaging device having a rectangular light receiving surface substantially parallel to the central axis of the light introducing surface portion, and on both left and right sides of the optical system element including the light introducing surface portion and the reflecting surface portion. A forceps in which an illumination window for irradiating a region to be imaged is formed, and a treatment tool for performing an appropriate treatment on the region to be imaged is projected on the side opposite to the solid-state image sensor with respect to the optical system element. In the electronic endoscope with a mouth formed, the shape of the solid-state imaging device is a rectangle that is long along the central axis direction of the light introduction surface portion and short in the direction connecting left and right illumination windows. Electronic endoscope. 2. The electronic endoscope according to claim 1, wherein a conductive connection portion such as a signal line connected to the solid-state image sensor is arranged at an end portion in the longitudinal direction of the solid-state image sensor. 3. The electronic endoscope according to claim 1, wherein a vertically long monitor screen is used as a monitor screen for displaying an image captured by the solid-state image sensor. 4. The reading direction of the solid-state imaging device is a direction along the short side of the solid-state imaging device, and the scanning line direction of the monitor screen is a horizontal direction along the short side of the screen. Electronic endoscope. 5. The reading direction of the solid-state image pickup device is a direction along the long side of the solid-state image pickup device, and the scanning line direction of the monitor screen is a vertical direction along the long side of the screen.
The described electronic endoscope.