JP2782779B2 - Electronic endoscope - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electronic endoscope.

2. Description of the Related Art Generally, an electronic endoscope is connected to a main body operation unit, and has a CC as an imaging unit at a distal end of an insertion unit introduced into a patient's body or the like.
A solid-state imaging device made of D or the like is provided, an image of an observation target portion is formed on the solid-state imaging device, and photoelectric conversion is performed by the solid-state imaging device. Then, the electric signal from the solid-state imaging device is transmitted to a processor, subjected to signal processing, and then displayed on a monitor device. Therefore, in the case of a side-view type endoscope as an imaging unit, an objective lens is disposed at an end of the insertion portion at an observation window opened to the side and formed by the objective lens. A solid-state imaging device is disposed at a position, and in a direct-view type endoscope, an objective lens is disposed at an observation window provided with an opening at a distal end surface of an insertion portion, and the objective lens and the solid-state imaging device Between them, a prism for bending the optical axis by 90 ° is provided.

[Problems to be Solved by the Invention] By the way, the viewing angle in the solid-state imaging device described above is
It is determined by the viewing angle of the objective lens and the imaging area of the solid-state imaging device, and cannot be changed according to the observation target portion. For example, when observing the inside of an organ such as the stomach, a wide viewing angle is required, but when examining a thin body tube such as the esophagus, a wide viewing angle is not required. Not only that, there is a disadvantage that the extra object comes into the field of view, which is rather distracting, which hinders intensive observation.

The present invention has been made in view of the above points, and an object of the present invention is to provide an electronic endoscope in which a viewing angle of a solid-state imaging device can be desirably limited according to an observation target portion. To provide a mirror.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention is provided above a light receiving area of a solid-state imaging device, and restricts the imaging area by partially covering the light receiving area. And a variable masking means including an opening area variable means for varying a masking area by the masking member.

[Operation] By adopting such a configuration, when a wide viewing angle is required, an image in a wide viewing range is displayed on the monitor device by opening the variable masking means. In the case where only a part of the observation target is extracted and the observation is performed intensively, the variable masking means is operated to narrow the viewing angle to the part to be observed.
As a result, only a portion necessary for observation is displayed on the monitor device, and an extra portion can be masked, which is convenient for inspection and diagnosis.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

First, FIG. 1 shows a cross section of a distal end portion in an insertion portion of a side-view type electronic endoscope. In the figure, reference numeral 1 denotes a distal end main body, and the distal end main body 1 is provided with an observation section 2 opening toward the side thereof, and an objective lens 3 is attached to the observation window 2. I have. A solid-state imaging device 4 such as a CCD is mounted on the image-forming position of the objective lens 3 so that the solid-state imaging device 4 can capture an image of an observation target.

A variable masking means is provided between the objective lens 3 and the solid-state imaging device 4, and is provided at a position above the light receiving region of the solid-state imaging device 4, and an aperture member 10 for changing the light receiving region is interposed. ing. As is apparent from FIG. 2, the aperture member 10 includes two aperture blades 11 and 12,
The aperture blades 11 and 12 are provided with notches 11a and 12a for forming aperture openings. And these aperture blades 1
The cutouts 1 and 12 are overlapped so that the cutouts 11a and 12a face each other. Therefore, the notches 11a,
Here, the aperture area is changed by relatively displacing the aperture blades 11, 12 constituting the masking member so that the apertures 12a approach and separate from each other. As aperture area changing means for changing the imaging area, the aperture blades 11 and 12 are provided with extension portions 11b and 12b, respectively.
1b, 12b are connected to the pivot pin 13, and the link plates 14a,
Connected to 14b. And these link plates 14a, 14b
Is connected to a pivot pin 15, and one end of an operation wire 16 is attached to the pivot pin 15.By pushing and pulling the operation wire 16, the diaphragm blades 11, 12 are brought close to each other. Or be separated from each other.

The aperture opening formed by the cutouts 11a and 12a of the aperture blades 11 and 12 always has a spring 17 mounted between the link plates 14a and 14b.
Is biased so as to be in a fully open state. If the operation wire 16 is pulled against the spring 17, the opening area of the aperture is reduced.
As shown in FIG. 3, the other end of the operation wire 16 is extended to the main body operation section in order to perform the pulling operation by remote control. Are linked. This slide 18 has a shaft 19
A drive pin 21 projecting from an operation lever 20 that can swing around the center is engaged.

By adopting such a configuration, for example, when observation is performed with a wide viewing angle inside the stomach or the like, the operation lever 20 is left as it is, and the aperture blade 1
The aperture opening formed between 1 and 12 is fully opened. Thereby, the solid-state imaging device 4 is displayed on the screen of the monitor device.
The image obtained from the entire imaging area is displayed.

On the other hand, when observing a narrow part such as an examination in the esophagus, if an extra part is displayed on the monitor screen, it becomes a sight and it is not possible to concentrate on the part to be actually observed There is. In such a case, the operation lever 20 is operated to pull the operation wire 16. As a result, the diaphragm blades 11 and 12 are displaced in a direction approaching each other, and the opening area of the diaphragm opening formed by the cutouts 11a and 12a decreases. As a result, the solid-state imaging device 4 is partially masked, so that the image area displayed on the monitor screen is narrowed down to only a part to be actually observed, and an extra part is removed from the screen. Can be.

Next, FIG. 4 shows a second embodiment of the present invention, in which a liquid crystal plate 30 is used as a masking member constituting a variable masking means. ing. In this liquid crystal plate 30, an annular liquid crystal 31 having a predetermined width is disposed concentrically without any gap. The liquid crystal plate 30 is interposed between the objective lens 3 and the solid-state imaging device 4, similarly to the aperture member 10 in the first embodiment described above.

The above-described liquid crystal 31 can transmit light in the state where no voltage is applied. Therefore, the reflected light from the observation target portion passes through the liquid crystal 31 and enters the solid-state imaging device 4. However, when a predetermined voltage is applied to the liquid crystal 31, that portion is shielded from light, and the portion of the imaging area of the solid-state imaging device 4 that faces the liquid crystal 31 in the light-shielded state is masked. Therefore,
By sequentially applying a voltage from the outer portion to the inner portion of the liquid crystal 31 provided in an annular shape, the solid-state imaging device 4
The area to be masked increases, and the imaging area can be narrowed down. And this liquid crystal
By driving 31, the imaging area of the solid-state imaging device 4 changes, so that the driving means of the liquid crystal 31 constitutes an opening area variable means. Therefore, for example, by providing an operation button or the like as the opening area changing means in the main body operation unit and operating the operation button or the like, a person who operates the endoscope can easily operate the endoscope at his / her own hand. The user can perform the operation of narrowing down the imaging area.

Note that the arrangement of the liquid crystals is not limited to the arrangement in which the annular liquid crystal is arranged concentrically, but may be arranged in a matrix.

[Effects of the Invention] As described above, the present invention has a configuration in which variable masking means for limiting the imaging area of the solid-state imaging device is provided above the light-receiving region of the solid-state imaging device. The range of the image displayed on the monitor screen can be set arbitrarily according to the target to be observed.If it is necessary to observe with a wide viewing angle, the masking means is set to the fully open state and narrowed to a predetermined portion. When performing observations, intensive observation is possible by activating the variable masking means and narrowing down the displayed image so that parts that do not need to be observed are not displayed on the monitor screen You will be able to break in.

[Brief description of the drawings]

FIGS. 1 to 3 show a first embodiment of the present invention. FIG. 1 is a sectional view of a distal end portion of an insertion portion of an endoscope, and FIG.
FIG. 3 is a plan view of an aperture member, FIG. 3 is a side view showing a drive mechanism of the aperture member, and FIG. 4 is a plan view of a liquid crystal plate showing a second embodiment of the present invention. 1: tip body, 3: objective lens, 4: solid-state image sensor, 10: aperture member, 11, 12: aperture blade, 11a, 12a: notch, 11b, 12b: extension, 13: pin, 14: long groove , 16: operation wire, 20: operation lever, 30: liquid crystal plate, 31: liquid crystal.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁶ , DB name) G02B 23/00 A61B 1/04

Claims (1)

(57) [Claims] 1. An electronic endoscope having a solid-state imaging device provided at a tip of an insertion portion and taking an image of an observation target by the solid-state imaging device, the electronic endoscope being disposed above a light receiving region of the solid-state imaging device. A masking member for limiting the imaging area by partially covering the light receiving region, and a variable masking means including an opening area variable means for varying the masking region by the masking member. Electronic endoscope.