JPH11125774A - Lighting method for image scope use, side view type image scope, and light guide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide lighting technology which clearly discriminates an object to be observed by the light and shade difference on an observed surface when the observed surface is observed through an image scope. SOLUTION: A side view type bore scope 1 is equipped with a main body 12 which is made of a long metal pipe, an objective optical member 14 which is arranged on the far end 12a of the main body 12 opposite the side (arrow A in the figure) of the main body 12, and an ocular optical member 16 which is arranged on the side of the near end 12b of the main body. A light guide 2 is equipped with a cylinder body 22 which is mounted slidably on the outer periphery of the main body 12, an optical fiber bundle 24 which transmits light made incident on an incidence end 24a to a projection end 24b, and a fixing screw 26 for fixing the cylinder body 22 at an arbitrary position of the main body 12. The projection end 24b projects illumination light in the direction wherein a shade is formed at one side part of unevenness on the observed surface and also emits illumination light in the direction wherein the illumination light reflected by the observed surface can not be made incident on the objective optical member 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an illumination technique for illuminating an observation surface in a bore with an image scope when observing the observation surface.

[0002]

2. Description of the Related Art Conventionally, various borescopes and fiberscopes (hereinafter, collectively referred to as “borescopes”) have been used to perform nondestructive visual inspections of parts that are difficult to directly observe, such as inside a machine or inside a tubular part. Image scope). The borescope has an objective lens on the distal end side of a main body made of a small-diameter metal tube, an eyepiece on the proximal end side, and an image guide consisting of many relay lenses or optical fiber bundles inside the main body. Thus, the optical transmission system is configured to be suitable for visually inspecting the inside of a straight tubular hole. In addition, the fiberscope is covered with a flexible tube so as not to impair the flexibility of the image guide composed of an optical fiber bundle, and an objective lens is disposed on a distal end side and an eyepiece is disposed on a proximal end side. Since it can be freely bent to some extent, it is suitable for visually inspecting the inside of a curved hole.

In the above-mentioned image scope, a small solid-state image pickup device is incorporated in the vicinity of the objective lens in place of an optical transmission system including a relay lens and a bundle of optical fibers, so that the objective lens can be moved through the objective lens. There is also an image scope which employs an electronic transmission system for transmitting an image obtained by converting the image into an electric signal.

[0004] As one of such image scopes, a type called a side view type has been conventionally known. For example, a side-view type borescope 80 shown in FIGS. 5A and 5B has a main body 82 made of a long metal tube.
And the objective optical member 8 disposed on the side of the main body 82 toward the side (in the direction of arrow A in the figure) on the distal end 82a side of the main body 82
4 and an eyepiece optical member 86 disposed on the proximal end 82b side of the main body 82, and an objective prism that bends the traveling direction of incident light by 90 degrees is used as the objective optical member 84. The light bent by the objective prism is applied to the main body 82.
Incident on an objective lens (not shown) incorporated in the
Further, the light is transmitted to the proximal end 82b of the main body 82 via some relay lenses (not shown). According to such a side-view borescope 80, when the main body 82 is inserted into the hole to be inspected, the objective optical member 84 is in a state of directly facing the surface to be observed in the hole, and the eyepiece optical member The image of the surface to be observed can be observed outside the hole body through 86.

[0005]

By the way, the side-viewing borescope 80 is provided with an optical fiber bundle for illumination (not shown) inside a main body 82 as a means for irradiating illumination light to a surface to be observed. Built-in. The illumination optical fiber bundle transmits light from an external light source incident on the incident end 90 on the proximal end 82b side of the main body 82 to the distal end 82a side of the main body 82, and Are emitted from an emission end 92 arranged so as to surround the object, and the light emitted from the emission end 92 is radiated to the surface to be observed as illumination light. In FIG. 5, the emission end 92 is represented by a mesh for the sake of convenience, but in reality, the ends of a large number of optical fibers are densely arranged within the range of the mesh display in the figure. Also in FIGS. 1, 3 and 4, which will be described later, the exit end of the illumination optical fiber bundle is represented by a similar mesh display.)

However, when the surface to be observed is observed with the side-viewing borescope 80 having the above-described structure, a difference in brightness different from that to be observed may occur on the surface to be observed depending on the state of the surface to be observed. In some cases, it is difficult to observe the surface to be observed due to the appearance.

More specifically, for example, as shown in FIG. 6, the side-view type borescope 80 is configured such that the direction of the field of view of the objective optical member 84 from the emission end 92 coincides with the center of the field of view indicated by the dotted line in FIG. The illumination light is emitted in substantially the same direction as the direction in which the illumination light is emitted. Therefore, the illumination light is irradiated not only to the intact portion on the observation surface F but also to the deepest portion of the flaw S (see arrow P1). However, the wound S
When the illumination light is radiated to the deepest part of the surface F, it is brightly illuminated from the intact part to the damaged part, and depending on the color and gloss of the material constituting the surface F to be observed, the brightness is determined by the presence or absence of the damage. There is a problem that the difference may be hard to appear, and as a result, it is extremely difficult to find the wound.

When the observation surface having a relatively high gloss is observed with the side-view type borescope 80 having the above structure,
Most of the light emitted from the emission end 92 is the observation surface F
, And enters the objective optical member 84 (arrow P2).
reference). Therefore, when the exit end 92 is reflected on the surface to be observed F, a difference in brightness may appear in the field of view irrespective of the state of the surface to be observed F itself. When the brightness is secured, there is a problem that the bright part is apt to cause halation. Of course, if the brightness of the illuminating light is suppressed, it is possible to prevent halation in a bright part, but this causes a problem that a dark part becomes too dark, and in any case, it becomes difficult to observe the observation surface F. Did not solve the problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a light-dark difference corresponding to the state of the surface to be observed itself or the state of the surface to be observed itself. An object of the present invention is to provide an illumination method when an image scope is used, in which an irrelevant contrast is prevented from appearing, so that an object to be observed can be clearly identified.
Another object of the present invention is to provide a side-view image scope and a light guide suitable for implementing the illumination method.

[0010]

In order to achieve the above object, an illumination method when an image scope is used according to the first aspect of the present invention includes an elongated main body and a distal end side of the main body. The objective body is inserted into the bore, the objective optical member is opposed to the surface to be observed in the hole, and the image of the surface to be observed is outside the hole. When using an image scope configured to be observable, in the method of irradiating the observation surface with the illumination light, the illumination light is emitted from a direction in which a shadow occurs on one side of the unevenness on the observation surface. Is irradiated.

Here, as a method of irradiating the illumination light from a direction in which a shadow occurs on one side of the unevenness on the surface to be observed, for example, the observation is performed only from one direction different from the visual field direction of the objective optical member. A method of irradiating the surface with illumination light and not irradiating it from the other direction, or changing the brightness greatly between light from one direction different from the visual field direction of the objective optical member and light from the other direction. A method of irradiating the observation surface with illumination light can be considered.

As for the angle of incidence on the surface to be observed (= the angle formed by the incident light beam with respect to the normal to the point of incidence on the surface to be observed), the greater the angle of incidence, the more clearly the shadow appears. Therefore, the smaller the unevenness to be identified at the time of observation, the larger the incident angle should be.

According to such an illumination method, since the presence of unevenness can be clearly identified by the shadow, the shadow is prevented from being formed on each part of the surface to be observed from the direction corresponding to the direction of the field of view of the objective optical member as in the prior art. As compared with the case where the illumination light is applied evenly, a difference in brightness is caused by the presence of unevenness such as the presence or absence of a flaw. As a result, there is an effect that irregularities on the surface to be observed are more easily found.

According to a second aspect of the present invention, there is provided an illumination method using an image scope, comprising: an elongated main body; and an objective optical member disposed on a distal end side of the main body. When inserted into the body, the objective optical member is opposed to the surface to be observed in the bore, and when using an image scope configured to be able to observe an image of the surface to be observed outside the hole, the surface to be observed is In the method of irradiating illumination light to the objective optical member, the illumination light is illuminated from a direction in which the illumination light specularly reflected on the surface to be observed cannot enter the objective optical member.

Here, as a method of irradiating the illumination light from the direction in which the illumination light regularly reflected on the surface to be observed cannot enter the objective optical member, all the illumination light regularly reflected within the field of view goes out of the field of view. A method of increasing the angle of incidence of the illumination light on the surface to be observed to such an extent that the light beam advances is considered.

According to such an illuminating method, since the radiating portion of the illuminating light is not reflected on the surface to be observed, there is no difference in brightness due to the presence or absence of the reflected light. As a result, halation does not occur partially, and the image does not become too dark partially, so that the entire surface to be observed can be observed well.

The illumination methods according to the first and second aspects can prevent light-dark differences different from those to be observed from appearing on the surface to be observed, even when used alone. In this case, the unevenness of the surface to be observed can be easily identified, and partial halation or the like can be prevented. That is,
By adopting both the illumination methods according to the first and second aspects, it is possible to enhance the effect of preventing a difference in brightness different from that to be observed from appearing on the surface to be observed.

Next, a side-viewing type image scope according to a third aspect of the present invention includes an elongated main body, and an objective optical member disposed on a distal end side of the main body toward the side of the main body. A side-view type image scope configured such that the main body is inserted into the hole, the objective optical member is opposed to the surface to be observed in the hole, and an image of the surface to be observed can be observed outside the hole. In the, there is a radiating portion of the illumination light at a position closer to the proximal end of the main body than the objective optical member, an illumination member capable of irradiating the observation surface with the illumination light radiated from the radiating portion The illumination member is disposed at a position where illumination light can be emitted from a direction in which a shadow is formed on one side of the unevenness on the surface to be observed.

According to this side-view image scope, the illumination member is arranged at a position where the illumination light can be emitted from a direction in which a shadow is formed on one side of the unevenness on the surface to be observed. It is suitable for carrying out the illumination method according to claim 1, and has an effect that irregularities on a surface to be observed are more easily found than in a conventional side-view image scope.

A side-view type image scope according to a fourth aspect of the present invention includes an elongated main body, and an objective optical member disposed on a distal end side of the main body toward the side of the main body. In this case, the main body is inserted into the bore, the objective optical member is opposed to the surface to be observed in the bore, and the image of the surface to be observed is configured to be observable outside the hole. A radiating portion for illuminating light at a position closer to a proximal end of the main body than the objective optical member, and an illuminating member capable of irradiating the surface to be observed with illuminating light radiated from the radiating portion. The illumination member is disposed at a position where the illumination light can be irradiated from a direction in which the illumination light regularly reflected on the surface to be observed cannot enter the objective optical member.

According to this side-view image scope, the illumination member is disposed at a position where the illumination light can be irradiated from a direction in which the illumination light that has been specularly reflected on the surface to be observed cannot enter the objective optical member. It is suitable for carrying out the illumination method according to claim 2, wherein, as in the conventional side-view image scope, halation occurs partially or an image becomes too dark partially. Thus, there is an effect that the observed surface can be favorably observed over the entire surface.

Further, in the side-view type image scope according to the third or fourth aspect, as in the fifth aspect, the illuminating member sets a distance from a radiating portion of the illuminating light to the objective optical member. If it is configured to be arbitrarily changeable, even if the distance from the observation surface to the objective optical member fluctuates, the distance from the illumination light emitting portion to the objective optical member can be arbitrarily changed, so that the observation surface can be changed. Since the angle of incidence of illumination light to the object can be adjusted to an appropriate range, one image scope can be used without having to design a dedicated image scope according to the distance from the surface to be observed to the objective optical member. .

Next, a light guide according to a sixth aspect of the present invention comprises an elongated main body, and an objective optical member disposed on a distal end side of the main body toward the side of the main body, The main body is inserted into the bore, the objective optical member is opposed to the surface to be observed in the bore, and the outer periphery of the main body of the side-view type image scope configured so that the image of the surface to be observed can be observed outside the hole. A light guide that can be mounted on the part, can be mounted at any position in the longitudinal direction of the main body, at the time of mounting,
A radiating portion for illuminating light is provided at a position closer to a proximal end of the main body than the objective optical member, and illuminating light radiated from the radiating portion can be radiated to the surface to be observed. The illumination light can be emitted from a direction in which a shadow is formed on one side of the unevenness on the observation surface.

According to this light guide, when it is mounted on the outer peripheral portion of the main body of the side-view type image scope, it becomes possible to irradiate the illumination light from a direction in which a shadow is formed on one side of the unevenness on the surface to be observed. It is suitable for carrying out the illumination method according to the first aspect. For example, even when a side-view type image scope having the same structure as that of the related art is used, there is an effect that a flaw on the surface to be observed is more easily found. .

According to a seventh aspect of the present invention, there is provided a light guide, comprising: an elongated main body; and an objective optical member disposed on a distal end side of the main body toward a side of the main body. The main body is inserted into the bore, the objective optical member is opposed to the surface to be observed in the bore, and the outer peripheral portion of the body of the side-view type image scope configured so that the image of the surface to be observed can be observed outside the hole. A light guide that can be mounted on the main body, can be mounted at any position in the longitudinal direction of the main body, at the time of mounting,
A radiating portion for illuminating light is provided at a position closer to a proximal end of the main body than the objective optical member, and illuminating light radiated from the radiating portion can be radiated to the surface to be observed. According to this light guide, it is possible to irradiate the illumination light from a direction in which the illumination light specularly reflected on the observation surface cannot enter the objective optical member. Then, it becomes possible to irradiate the illumination light from the direction in which the illumination light specularly reflected on the surface to be observed cannot enter the objective optical member, which is suitable for implementing the illumination method according to the second aspect. Even if a side-view image scope with the same structure is used, halation does not occur partially and the image does not become too dark, so that the entire observation surface can be observed well. When it comes There is an effect.

In the present invention, the above-mentioned side-view type image scope is usually an image scope provided with an optical member such as a prism or a mirror as an objective optical member for bending the traveling direction of incident light by 90 degrees. I can think. However, such an objective optical member for side viewing may not be directly incorporated in the image scope main body, for example,
It may be provided as a side viewing adapter that can be selectively attached to the image scope body. If the image scope is compatible with such an adapter, the image scope can be arbitrarily changed to a direct-view type or a side-view type by selectively mounting a direct-view adapter or a side-view adapter.

Also, as already described as a prior art, an image scope incorporating a small solid-state image pickup device is known. However, such an image scope has a structure in which the small solid-state image pickup device itself is directed sideways. By
Since a side-view type image scope can be configured,
In this case, an objective lens or the like may be used as the objective optical member. That is, the objective optical member in the present invention is not limited to an optical member having a function of bending the traveling direction of incident light by 90 degrees.

Further, in the case of the fiberscope, the direction of the field of view of the objective lens itself is fixed so as to coincide with the axial direction of the distal end of the main body, but the distal end of the main body is operated by operating the proximal end side of the main body. Some allow only a portion of the end to bend in the desired direction. Such a fiberscope functions as both a direct-view type and a side-view type by bending the distal end of the main body in a necessary direction, and this is also included in the side-view type image scope referred to in the present invention. It is.

[0029]

Next, an embodiment of the present invention will be described with reference to an example. As shown in FIGS. 1A and 1B, an image scope exemplified as an embodiment is as follows.
This is configured by combining a light guide 2 with a side view type borescope 1.

The side-view borescope 1 is disposed on the distal end 12a side of the main body 12 in the direction of the arrow A in the figure. It comprises an objective optical member 14 and an eyepiece optical member 16 disposed on the proximal end 12b side of the main body 12.

The main body 12 has substantially the same internal structure as that of the conventional product described above, except that the main body 12 does not include the optical fiber bundle for illumination unlike the conventional product. Further, the objective optical member 14 is an objective prism that bends the traveling direction of the incident light by 90 degrees, similarly to the conventional product described above. Eyepiece optical member 1
The eyepiece 6 is also the same as the conventional eyepiece. The light incident on the objective optical member 14 is bent in the traveling direction by the objective optical member 14, the light is incident on an objective lens (not shown) incorporated inside the main body 12, and further, some relay lenses ( The proximal end 12b of the body 12 via a not shown)
Is transmitted to the eyepiece optical member 16.

On the other hand, the light guide 2 comprises a cylindrical body 22 slidably mounted on the outer periphery of the main body 12 and an incident end 24.
The optical fiber bundle 24 is provided with an optical fiber bundle 24 for transmitting light incident on a to the emission end 24b, and a fixing screw 26 for fixing the cylindrical body 22 to an arbitrary position of the main body 12.

The cylindrical body 22 is a resin component for holding the emission end 24b side of the optical fiber bundle 24 at a specific position in a specific direction. The outer peripheral portion of the optical fiber bundle 24 is covered with a flexible resin tube 28, and a connector 30 for connecting to an external light source is provided on the incident end 24 a side of the optical fiber bundle 24. On the other hand, the emission end 24b side of the optical fiber bundle 24 is separated inside the tubular body 22,
As shown by a mesh in FIG. 1B, the cylindrical body 22 is arranged so as to be exposed to the outside at one end face 22 a of the cylindrical body 22, and is arranged so as to surround the outer periphery of the main body 12.

The fixing screw 26 is a member for restricting the sliding of the cylindrical body 22 with respect to the main body 12 by being pressed against the main body 12 while being screwed to the cylindrical body 22, and is used when the fixing screw 26 is loosened. Only the cylindrical body 22 can be slid. In the side-viewing borescope 1 and the light guide 2 configured as described above, the light guide 2
Is located at a position closer to the proximal end 12b of the main body 12 than the objective optical member 14 of the side-view type borescope 1, there is an output end 24b (illumination light emitting portion) of the optical fiber bundle 24, as shown in FIG. In addition, it is possible to irradiate the observation surface F with illumination light emitted from the emission end 24b.

In particular, unlike the conventional product, the object optical member 14 is irradiated with illumination light from a direction in which a shadow is formed on one side of the unevenness on the surface F to be observed, and is in a direction in which the shadow can be observed. The observation of the observation surface F is performed via the. Therefore, for example, as shown in FIG. 2, when there is a flaw S on the observation surface F, the interior of the flaw S is not irradiated with illumination light (see P1 in the figure). As a result, a shadow is formed inside the scratch S, and a difference in brightness is caused depending on the presence or absence of the scratch S. Therefore, the scratch S can be found very easily.

Further, unlike conventional products, the illumination light is radiated from a direction such that the illumination light regularly reflected on the observation surface F does not enter the objective optical member 14 (see P2 in the figure). That is, the visual field range of the objective optical member 14 (Q in the figure)
1-Q2), the specularly reflected light passes through the objective optical member 1
Illumination light is incident at an incident angle larger than the maximum incident angle (θ in the figure) that can enter the illumination light 4. Therefore, the emission end 24b of the optical fiber bundle 24 does not appear on the surface F to be observed at least in the visual field range of the objective optical member 14. Therefore, even if the external light source is brightened, halation does not occur partially as in the related art, and the image does not partially become too dark, so that the entire observation surface F can be observed well. become able to.

Although the embodiments of the present invention have been described above, various specific embodiments other than those described above are conceivable for the embodiments of the present invention. Hereinafter, useful modifications will be described. In the above-described embodiment, the side-viewing borescope 1 and the light guide 2 are configured separately from each other, and the two are combined to form a side-viewing type borescope with a lighting mechanism. 3 (a),
As in the side view type borescope 4 shown in FIG. 4B, an integrated type in which an optical fiber bundle for illumination is incorporated inside may be used. That is, in the side-view borescope 4, the main body 40 is a double tube constituted by the inner cylinder 42 and the outer cylinder 44, and the light from the surface to be observed is objectively provided inside the inner cylinder 42. An image transmission path for transmitting the light from the optical member 46 to the eyepiece optical member 48 is formed. On the other hand, in the gap between the inner cylinder 42 and the outer cylinder 44, the light from the external light source for illumination
An optical fiber bundle for illumination, which transmits light from 0 to the emission end 52, is provided. The emission end 52 of the illumination optical fiber bundle is arranged so as to surround the inner cylinder 42 at the end face of the outer cylinder 44, and the light emitted from the emission end 52 is illuminated on the surface to be observed as illumination light. Even with such a side-view type borescope 4 with an illumination mechanism, the illumination light is not radiated in the direction of the field of view unlike a conventional product, so that irregularities on the surface to be observed can be easily identified, and There is no problem that light specularly reflected on the observation surface is incident on the objective optical member 46 and causes partial halation.

Both the light guide 2 and the side-view borescope 4 have a structure in which the emission ends of the optical fiber bundle for illumination are arranged in a ring around a portion having a built-in image transmission system. However, for example, FIG.
(A) As in a side-view type borescope 6 shown in FIG. 7 (b), the output end 60 is connected to the objective optical member 62 by using a minimum optical fiber bundle necessary for irradiating the visual field range.
May be arranged in a state where it is biased to a position close to. With such a structure, the diameter can be made smaller than that of the above-described side-view type borescope 4, and the amount of optical fibers can be reduced without deteriorating the function, and the cost can be reduced. . However, as for the light guide 2 described above, for those that are separate from the borescope body,
If the exit end of the optical fiber bundle is biased to a specific position, it is necessary to optimize the mounting angle with respect to the borescope body. Therefore, in this case, it is better to provide a structure that can be mounted only at a specific mounting angle in order to optimize the mounting angle, or to arrange the output end of the optical fiber in an annular shape.

Furthermore, in each of the embodiments described above, the main part of the present invention has been described in detail by taking a borescope having an optical image transmission system as an example. If technology is adopted, in addition to the optical transmission system,
An electronic transmission system may be adopted. Further, the present invention can be applied to an image scope other than the bore scope, specifically, a fiber scope.

In addition, in the above-described embodiment, as the illuminating means, an example in which light from an external light source is transmitted by a light guide to irradiate the illuminated surface has been exemplified, but a self-luminous light emitting element is incorporated as a light source. Even in the case of an image scope, the position of the light source was changed to a position where illumination light could be irradiated from the direction in which a shadow occurs on one side of the unevenness on the surface to be observed, or it was specularly reflected on the surface to be observed By setting the illumination light at a position where the illumination light can be irradiated from a direction in which the illumination light cannot enter the objective optical member, the illumination method of the present invention can be implemented.

The side-viewing borescope 1 and the light guide 2 may be combined to provide a side-viewing type borescope with an illumination mechanism.
May be provided by itself and used in combination with an existing side-view type borescope.

[Brief description of the drawings]

1A and 1B show an assembly of a side view type borescope and a light guide, wherein FIG. 1A is a side view and FIG. 1B is an enlarged front view of a main part thereof.

FIG. 2 is a cross-sectional view showing a state where illumination light from the light guide is incident on a surface to be observed.

FIG. 3 shows a side-view type borescope with a lighting mechanism,
(A) is the side view, (b) is the enlarged front view of the principal part.

FIG. 4 shows another side-viewing borescope with a lighting mechanism,
(A) is the side view, (b) is the enlarged front view of the principal part.

5A and 5B show a conventional side-view type borescope, in which FIG. 5A is a side view and FIG. 5B is an enlarged bottom view of a main part thereof.

FIG. 6 is a cross-sectional view showing a state in which illumination light from a light guide incorporated in a conventional side-view borescope enters a surface to be observed.

[Explanation of symbols]

1, 4, 6 ... side-view type borescope, 2 ... light guide, 12, 40 ... body, 14, 46, 62 ...
-Objective optical member, 16, 48 ... eyepiece optical member, 22
... cylindrical body, 24 ... optical fiber bundle, 26 ... fixing screw, 28 ... resin tube, 30 ... connector, 42 ... inner cylinder, 44 ... outer cylinder.

Claims (7)

[Claims] 1. An object comprising an elongated main body and an objective optical member disposed on a distal end side of the main body, wherein the main body is inserted into a hole, and the objective optical member is inserted into the hole. A method of irradiating illumination light on the surface to be observed when using an image scope configured to be opposed to a surface to be observed and to be able to observe an image of the surface to be observed outside the hole body; An illumination method using an image scope, wherein illumination light is emitted from a direction in which a shadow occurs on one side of the unevenness on the surface. 2. An object comprising an elongated main body and an objective optical member disposed on a distal end side of the main body, wherein the main body is inserted into a hole, and the objective optical member is inserted into the hole. A method of irradiating illumination light on the surface to be observed when using an image scope configured to be opposed to a surface to be observed and to be able to observe an image of the surface to be observed outside the hole body; An illumination method when an image scope is used, wherein the illumination light is irradiated from a direction in which illumination light specularly reflected on a surface cannot enter the objective optical member. 3. An elongate main body, and an objective optical member disposed at a distal end side of the main body toward a side of the main body, wherein the main body is inserted into a hole, In a side-view type image scope configured such that the objective optical member is opposed to a surface to be observed in a bore and an image of the surface to be observed can be observed outside the hole, a position closer to the main body than the objective optical member There is a radiating portion of the illumination light at a position near the end, comprising an illumination member capable of irradiating the observation surface with the illumination light emitted from the radiation portion, wherein the illumination member is provided on the observation surface. A side-view image scope, which is arranged at a position where illumination light can be emitted from a direction in which a shadow occurs on one side of a certain unevenness. 4. An elongated body, and an objective optical member disposed on a distal end side of the body toward the side of the body, wherein the body is inserted into a hole, In a side-view type image scope configured such that the objective optical member is opposed to a surface to be observed in a bore and an image of the surface to be observed can be observed outside the hole, a position closer to the main body than the objective optical member A radiating portion for illuminating light is provided at a position close to the end, and an illuminating member capable of irradiating illuminating light radiated from the radiating portion to the surface to be observed is provided. A side-view type image scope, wherein the reflected illumination light is arranged at a position where the illumination light can be irradiated from a direction in which the reflected illumination light cannot enter the objective optical member. 5. The side-view image scope according to claim 3, wherein the illuminating member is configured to be able to arbitrarily change a distance from a radiating portion of the illuminating light to the objective optical member. A side-view type image scope characterized by the following. 6. An elongated body, and an objective optical member disposed on a distal end side of the body toward a side of the body, wherein the body is inserted into a hole, A light guide that can be attached to an outer peripheral portion of a main body of a side-view image scope configured so that the objective optical member is opposed to a surface to be observed in a bore and an image of the surface to be observed can be observed outside the body. The main body can be mounted at an arbitrary position in the longitudinal direction, and at the time of mounting, there is a radiating portion of illumination light at a position closer to the proximal end of the main body than the objective optical member, and the radiating portion is radiated from the radiating portion. A light guide capable of irradiating the observation surface with the illumination light, and in particular, irradiating the illumination light from a direction in which a shadow occurs on one side of the unevenness on the observation surface. . 7. An elongate main body, and an objective optical member disposed at a distal end side of the main body toward the side of the main body, wherein the main body is inserted into a hole, A light guide that can be attached to an outer peripheral portion of a main body of a side-view image scope configured so that the objective optical member is opposed to a surface to be observed in a bore and an image of the surface to be observed can be observed outside the body. The main body can be mounted at an arbitrary position in the longitudinal direction, and at the time of mounting, there is a radiating portion of illumination light at a position closer to the proximal end of the main body than the objective optical member, and the radiating portion is radiated from the radiating portion. It is possible to irradiate the observation surface with the illumination light, and in particular, it is possible to irradiate the illumination light from a direction in which the illumination light specularly reflected on the observation surface cannot enter the objective optical member. Light guide to do.