JPH01209417A - Endoscope device - Google Patents

Abstract

PURPOSE:To obtain an easy-to-see image by radiating irradiation light principally outside the range of the observation visual field of an object and making an observation with indirect light. CONSTITUTION:Illumination is performed principally outside the range of the observation visual field of the object, which is observed with the indirect light. Here, what is called direct lighting i.e. light is projected directly toward the visual field range of the object by the optical system 4 at a scope tip part 1 is not employed, so the regularly reflected light of the irradiation light from the object surface is hardly incident on the optical system 4. Therefore, the regular reflected light becomes hard to generate halation and an extremely large light-dark image difference. Consequently, the easy-to-see image is obtained.

Description

[Detailed Description of the Invention] [Purpose of the Invention (Field of Industrial Application) This invention relates to an endoscope device for observing the inside of a body cavity or a mechanical device (hereinafter referred to as the inside of a body cavity), and particularly relates to The present invention relates to an improvement in which an object to be observed is indirectly illuminated in a device.

(Prior Art) In general, the 3M device for family celebrations is used to introduce an endoscope into a body cavity or the like and observe a subject such as an organ.

Light supplied from a light source in the main body of the apparatus is guided to the distal end of the scope by a light guide or the like, and is emitted from an irradiation window at the distal end of the scope to illuminate the subject. The reflected light from the illuminated object enters an optical system such as an objective lens fitted into the observation window at the tip of the scope, and is converted into an electrical signal by an image sensor, for example, and sent to an endoscopic IM device outside the object to be observed. The image is sent to the main body, and the subject image can be observed on the main body side of the device. Alternatively, there is also one in which the light incident on the optical system is guided by a fiber scope so that it can be observed outside the object to be observed.

In conventional endoscope apparatuses, illumination is performed by the so-called M, contact illumination method, in which light guided by a light guide is directly irradiated toward a subject within the field of view of the optical system at the distal end of the scope.

The above-mentioned scopes can be used with any of the scopes, such as the forward-viewing type that observes the subject on the longitudinal extension of the scope, the side-viewing type that observes in a direction perpendicular to the scope's longitudinal direction, or the oblique-viewing type that observes diagonally forward. Direct lighting method was used.

(Problem B to be solved by the invention) However, in an endoscope device using such a direct illumination method,
When illumination light is directly irradiated onto the subject within the field of view of the optical system from the irradiation window at the tip of the scope introduced into the body cavity,
The light reflected from the surface of the subject is directly reflected light (regularly reflected light).
This makes it easier for the light to enter the imaging unit and the like. An image portion caused by such specularly reflected light may cause halation or the like, turning that portion of the image pure white. Furthermore, the difference between brightness and darkness of the image becomes large, and the dynamic range of the image sensor may be exceeded, resulting in invisible portions.

The present invention suppresses the occurrence of halation by irradiating using an indirect illumination method that is less likely to produce such specularly reflected light, and reduces the difference in brightness at the edges of the image to improve the visibility of invisible areas. It is an object of the present invention to provide an endoscope device that can reduce the number of occurrences and provide easy-to-see images.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve such an object, in the endoscope device according to the present invention, a scope is introduced into the object to be observed, and from the distal end of the scope, In this device, which emits illumination light to observe a subject, the ff! It is characterized by a configuration in which the irradiation light is mainly emitted outside the observation field and observation is performed using indirect light.

(Function) As described above, the endoscope device according to the present invention is configured to primarily illuminate the outside of the observation field of view of the subject and perform observation using indirect light. Since so-called direct illumination, in which light is irradiated directly toward the field of view of the subject, is not used, the specularly reflected light that is reflected from the subject's surface is less likely to enter the optical system. Halation caused by light and extreme differences in brightness in large images are less likely to occur. In this way, it becomes possible to obtain an image that is easier to see.

(Example) Next, each example to which this invention is applied will be described based on the drawings. FIG. 1 is a schematic diagram showing the distal end of a scope of an endoscope apparatus according to an embodiment of the present invention. In this embodiment, a forward-looking scope that observes a subject on the longitudinal extension of the scope will be described.

In FIG. 1, reference numeral 1 indicates a forward-looking scope tip. Reference numeral 2 denotes a light guide made of a glass fiber bundle, and this light guide 2 guides light emitted from an irradiation light source of an endoscope body (not shown) to an illumination light emitting section 3. The illumination light emitting section 3 is formed in a cylindrical shape and is fixed to the scope tip 1 by appropriate means. An optical system 4 consisting of an objective lens and the like is attached to the distal end surface 1a of the distal end portion 1. 5 is an imaging probe such as a CCD;
This image sensor 5 is placed behind the optical system 4, receives the light incident through the optical system 4, performs photoelectric conversion, and converts it into an electrical image signal through a signal line 6 to the endoscope body (not shown). Sending out.

Next, the operation of this embodiment of the device will be explained.

Using this device, the operator etc. can perform 3 AItl! When performing an observation, etc., first turn on the power to the endoscope (not shown) and turn on the irradiation light source in the main body.Next, while operating the scope operation part (not shown), insert the end of the scope into the body cavity, etc. Insert 1. At this time, the light emitted from the light source passes through the light guide 2 and is guided to the illumination light emitting section 3. The light guided to the illumination light emitting section 3 is emitted from the rotation section 3 toward the side surface of the scope tip section 1. The emitted light is repeatedly reflected diffusely within the body cavity, etc., and indirectly illuminates a subject (not shown) within the field of view by the optical system 4 of the scope tip 1a.9 The reflected light from the indirectly illuminated subject is The light is received by the imaging device 5 through the optical system 4 at the distal end of the scope and photoelectrically converted.

Then, it is sent as an electrical video signal to the endoscope main body (not shown) via the signal line 6, and the image of the subject can be observed on the main body side.

Note that when observing the inside of a body cavity of a living body, the illumination light emitting section 3 may be made of plastic, acrylic, or the like, which is a transparent material that is not easily corroded by gastric juices and is used in artificial organs, etc. Alternatively, a configuration may be adopted in which chemical-resistant glass is processed into a cylindrical shape, the inner surface and both end surfaces of the cylinder are formed into mirror shapes, and light is emitted from the outer surface of the cylinder.

In this way, since the device of this embodiment uses the indirect illumination method for illumination, the amount of specularly reflected light entering is significantly reduced.
Halation etc. are less likely to occur. Furthermore, the uniform illumination light can reduce the difference in brightness within the body cavity. Therefore, according to this device, it becomes possible to capture a subject image within the dynamic range of the image sensor 5, and it becomes possible to obtain an image that is easy to view.

Next, a second embodiment of the present invention will be described with a schematic diagram shown in FIG. 2.

In FIG. 2, reference numeral 11 denotes a distal end portion of a side-viewing scope, and an illumination light emitting portion 13 is provided on a distal end surface 11a of the distal end portion 11.
is installed. Reference numeral 2 denotes a light guide, and the light guide 2 guides light emitted from the irradiation light source of the endoscope body to the illumination light emitting section 13 . Reference numeral 4 denotes an optical system, and this optical system 4 is disposed in a side window portion of the distal end portion 11 of the side-viewing scope. Reference numeral 5 denotes a VI image element such as COD, which receives light incident from the optical system 4 in the side window, converts it into an electrical video signal by photoelectric conversion, and sends it to the main body of the apparatus.

Next, the operation of this second embodiment will be explained.

When an operator performs endoscopic observation using this device,
As in the above embodiment, the irradiation light source of the endoscope body is turned on, and the scope distal end 11 is inserted into the body cavity or the like while operating the scope operating section (not shown). At this time, the light emitted from the light source passes through the light guide 2 to the illumination light emitting section I.
Guided by 3.

The light guided to the illumination light emitting section 13 is radiated forward of the scope distal end 11 from the distal end surface 11a. The light emitted from the illumination light emitting section 13 is repeatedly reflected diffusely within the body cavity, etc., and indirectly illuminates an object (not shown) within the field of view of the optical system 4 on the side surface of the scope distal end section 11. The reflected light from the indirectly illuminated object passes through the optical system 4 of the scope tip 11 and is received by the image sensor 5, and is sent as an electrical video signal to the device main body (not shown), where the object is detected. Images can be observed.

Note that the illumination light emitting section 13 may be made of transparent plastic, acrylic, or glass with a mirror-like bottom surface, as in the above-mentioned embodiment. It will be even more effective if a lens is provided to illuminate the front of the scope over a wide angle.

In this way, the side-viewing endoscope of the second embodiment can also implement the indirect illumination method and exhibit the same excellent effects as the device of the first embodiment.

FIG. 3 is a diagram showing an outline of a third embodiment of the present invention.

In this figure, reference numeral 21 denotes a forward-looking endoscope tip, and an optical system 4 is attached to a tip surface 21a of this tip 21. As shown in FIG. 23 is a light emitting section in which light emitting elements such as high brightness laser diodes and high brightness LEDs are arranged in a cylindrical shape.

Next, the operation of this third embodiment device will be explained.

When an operator such as a doctor performs endoscopic observation using this device, the distal end portion 21 of the scope is inserted into a body cavity or the like in the same manner as in the first embodiment and the second embodiment. At this time, the light emitting part 2 is powered by power supplied from the endoscope body (not shown).
3 emits light, and the emitted light is emitted toward the side surface of the scope tip 21. Then, the light emitted from the light emitting unit 23 repeatedly irradiates randomly within the body cavity, etc., and indirectly illuminates the subject within the field of view of the optical system 4 on the distal end surface 21a of the distal end portion 21 of the scope. The reflected light from the subject that has been indirectly illuminated in this way enters the optical system 4, is received by a photoelectric conversion element in the imaging section (not shown) behind it, and is sent to the main body of the device as an electrical image signal, which produces an image of the subject. observation.

In this way, it is also possible to configure an endoscope apparatus using an indirect illumination method to which the present invention is applied, using light emitting elements such as high-intensity laser diodes and high-intensity LEDs.

Although illustration and description are omitted, it is of course possible to apply the indirect illumination using the above-mentioned light emitting element to a side-viewing type or front-viewing endoscope.

In addition to the same excellent effects as the above-described first and second embodiments, the device of the third embodiment can reduce the number of parts by configuring the device without using a light guide or the like. Therefore, it is possible to reduce the diameter of the scope, and it is possible to more easily introduce the scope into a body cavity during endoscopic observation.

In each of the above-mentioned embodiments, an example of an endoscope that uses an image sensor such as a COD was explained. It goes without saying that the present invention can be similarly applied to mirror devices.

[Effects of the Invention] As described above, according to the present invention, the interior of the body cavity, etc. is entirely illuminated with indirect illumination light, and the object within the observation field of view is not directly irradiated with the illumination light. The entire area is uniformly and brightly illuminated by indirect illumination light. Since it does not rely on direct illumination light, the influence of specularly reflected light is significantly reduced, halation and the like are less likely to occur, and differences in brightness and darkness within the body cavity are also reduced. Therefore, easy-to-see endoscopic images can be obtained, and yA? You can improve the efficiency of ¥, etc. If the endoscope uses a large image sensor, etc., its dynamic range will be small, and it will be possible to obtain images with appropriate exposure suitable for display on display devices such as color monitors with limited dynamic ranges. become.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing one embodiment of the invention, FIG. 2 is a schematic diagram showing a second embodiment of the invention, and FIG. 3 is a schematic diagram showing a third embodiment of the invention. 1.11.21... Scope tip 1a, lla. 21a... Scope tip surface 2... Light guide
3.13... Illumination light emitting section 23... Light emitting section 4.
...Optical system 5...Image sensor 6...Signal line

Claims (1)

[Claims] (1) In an endoscope device in which an endoscope is introduced into the object and the object is observed by emitting illumination light from the distal end of the scope, the irradiation light is mainly applied outside the observation field of view of the object. An endoscope device characterized in that it is configured to emit light and perform observation using indirect light.