JPH04104214A - Observation device - Google Patents

Abstract

PURPOSE:To light an observed surface brightly and uniformly by providing a deflecting element which bends an optical axis of lighting toward an observation optical system in an optical path of light emitted by a lighting optical system and bending the optical axis of the observation optical system and the optical axis of illumination light projected by a deflecting element sideward by a reflecting mirror. CONSTITUTION:An objective 1 and a solid-state image pickup element 2 constitute the observation optical system and a light guide 3 and a polarizing prism 4 constitute the lighting optical system respectively; and the polarizing prism 4 functions as the deflecting element which bends the optical axis of illumination light toward the observation optical system. A visual field conversion prism 1c bends the optical path and the solid-state image pickup element 2 is arranged slantingly so that the solid-state image pickup element 2 is housed compactly in the device. Namely, the reflecting mirror, observation optical system, and solid-state image pickup element are arranged so that the length direction of a tube to be measured matches a horizontal scanning direction in an image formed on the solid-state image pickup element; and a signal is extracted by horizontal scanning and the length of a weld zone is calculated by conversion of the signal. Consequently, the observed surface is lighted uniformly and brightly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an observation device, and particularly to a side-view observation device suitable for observing the inner surface of a tube.

[Conventional technology]

In recent years, side-viewing endoscopes have been widely used to inspect damage on the inner surface of gas pipes, water pipes, etc., and to inspect the welding conditions of pipe connections. As shown in FIG. 14, the illumination optical system includes a light guide and an illumination lens provided at the exit end of the light guide, and the observation optical system includes a side viewing prism, an objective lens, and an image guide. The exit end and the entrance end are arranged in order in the longitudinal direction of the endoscope body, and the illumination light is directed in front of the entrance end of the observation optical system (Utility Model No. 53-10
1482) and as shown in FIGS. 15 and 16, a reflecting mirror is placed on the optical axis of the observation optical system of a forward-viewing endoscope, and the illumination light emitted from the illumination optical system is reflected from this mirror. A device configured to direct the observation light onto the surface to be observed through a reflection mirror and to introduce observation light from the surface to be observed into the observation optical system through the reflection mirror (Utility Model No. 62-9431).
No. 2 and Japanese Unexamined Patent Publication No. 61-109013) are known.

[Problem to be solved by the invention]

By the way, in the conventional example shown in FIG. 14, when the inner diameter of the tube to be observed is not much larger than the diameter of the endoscope body, the distance between the entrance end of the observation optical system and the surface to be observed is Because it is short, there is a problem that the effect of parallax due to the separation between the entrance end of the observation optical system and the exit end of the illumination optical system becomes noticeable, and one side of the field of view becomes dark, making it impractical for practical use.

Additionally, if the surface to be observed is relatively close to a mirror surface, there is a problem in that the image of the exit end face of the illumination optical system reflected from the surface to be observed enters the field of view, causing strong halation in this area, which hinders observation. .

In addition, the conventional example shown in FIG.
(Refer to the publication), the illumination light directed from the exit end of the illumination optical system toward the observed surface and the observation light directed from the observed surface toward the input end of the observation optical system are reflected by a common reflection mirror. Therefore, even if the inner diameter of the tube to be observed is not very large compared to the diameter of the endoscope body, the optical path length from the surface to be observed to the exit end of the illumination optical system and the input end of the observation optical system is relatively long. Therefore, the influence of parallax is smaller compared to the conventional example shown in FIG. If the light distribution angle is widened in order to eliminate unevenness, the illumination efficiency decreases, which poses a practical problem.Furthermore, when the surface to be observed is close to a mirror surface, problems similar to those of the conventional example shown in FIG. 14 occur.

Furthermore, the conventional example shown in FIG.
13) is different from the conventional example shown in Fig. 15 in that the exit end of the illumination optical system is arranged in an annular shape.
There are problems similar to those of the conventional example shown in FIG.

The present invention has been made in view of the above-mentioned problems of the conventional technology, and its purpose is to solve the problem when the inner diameter of the tube to be observed is relatively large compared to the outer diameter of the main body of the device. The surface to be observed can be illuminated brightly and uniformly from a relatively large distance to a slightly large distance, that is, from a relatively distant position to a close position.
Moreover, even when the inner surface of the tube is close to a mirror surface, the image at the output end of the illumination optical system does not cause halation in the observation field, and a good observation image can always be obtained, as shown in Fig. 15 or 16. The aim is to provide equipment.

[Means to solve the problem]

In order to achieve the above object, the observation device according to the present invention includes:
The optical path of the light emitted from the illumination optical system is equipped with a deflection element that bends the illumination optical axis to approach the observation optical system, and the optical axis of the observation optical system and the illumination optical axis emitted from the deflection element are connected by a reflecting mirror. The reflective surface that bends the optical axis of the illumination optical system is tilted so that the illumination optical axis approaches the observation optical axis relative to the reflective surface that bends the optical axis of the observation optical system. It is arranged as follows.

In addition, a polarizing element is provided in each of the observation optical system and the illumination optical system,
The polarizing elements are arranged so that their vibration directions are substantially perpendicular, or at least one polarizing element is arranged so that it can rotate around the optical axis.

[For production]

By using a reflective mirror to bend the observation optical axis and illumination optical axis so that they reach the observed object surface, the observation optical axis can be bent to reach the observed object surface. A certain distance is ensured from the exit surface of the illumination optical system to the surface to be observed even in the case of Therefore, by arranging a deflection element in front of the exit surface of the illumination optical system, or by arranging a reflective mirror that reflects the illumination light at an angle, the difference between the illumination range and the observation range on the observed surface, so-called parallax ( Parallax) can be reduced.

In addition, polarizing elements arranged in the illumination optical system and the observation optical system so that the vibration directions are almost perpendicular to each other allow the specular reflection component on the observed surface to be removed from the observation light that reaches the observer's eye or the image sensor. is effectively removed. In this case, by rotating at least one of the polarizing elements around the optical axis,
The specular reflection component can be appropriately leaked into the observation field of view, thereby making it possible to appropriately brighten the observed image.

〔Example〕

Hereinafter, the present invention will be described in detail based on the illustrated embodiments.

FIG. 1 shows a first embodiment of the invention. In the figure, ■ indicates an infrared cut filter 1a held between glass plates, an optical low-pass filter lb that uses birefringence such as a crystal filter to remove moiré, and a visual field conversion prism lc.
2 is a solid-state image sensor such as a CCD, 3 is an objective lens including
4 is a light guide, 4 is a deflection prism provided at the exit end of the light guide 3, 5 is a reflective mirror having a reflective surface 5a, and S is a surface to be observed such as the inner surface of a tube. In this case, the objective lens l and the solid-state image sensor 2 constitute an observation optical system, and the light guide 3 and the deflection prism 4 constitute an illumination optical system, respectively.
The deflection prism 4 functions as a deflection element that bends the illumination optical axis toward the observation optical system. In this example,
In order to store the solid-state image sensor 2 compactly within the apparatus, the optical path is bent by a visual field conversion prism lc and the solid-state image sensor 2 is disposed diagonally. The horizontal scanning direction of this solid-state image sensor is the direction shown by the arrow in FIG. has been done. That is, the reflecting mirror, observation optical system, and solid-state image sensor are arranged so that the longitudinal direction of the tube to be measured in the image formed on the solid-state image sensor coincides with the horizontal scanning direction, and the signal is detected by horizontal scanning. The length of the welded portion is calculated from the signal.

FIG. 2 shows various configuration examples of the illumination optical system, in which a deflection element 4 is provided directly or indirectly at the exit end of the light guide 3, and the illumination light is reflected by the reflection surface 5a of the reflection mirror 5. The observation range and the illumination range match each other by the time the light reaches the surface S to be observed. That is, FIG. 2(A)
2B shows an example in which a wedge prism is used as the deflection element 4, and FIG. 2D shows an example in which a wedge concave lens is used as the deflection element 4. Figure 2 (
In B), since the wedge surface is placed on the light guide 3 side, there are advantages such as the refraction is performed twice and the refraction angle can be increased, and the front surface is flat. In either case, since the center of the illumination light is made to substantially coincide with the center of the observation range, it is possible to outperform conventional systems in terms of light distribution and illumination efficiency. In FIGS. 2C and 2E, a single fiber is interposed between the light guide 3 and the deflection element 4, and the deflection element 4 is also made of a single fiber. This configuration example is suitable when it is necessary to increase the light distribution angle of illumination light or when it is necessary to configure the illumination optical system with a small diameter and compactly.

In this case, the relatively long single fiber 4' is used because reflection at the boundary with the cladding on the side surface of the deflection element 4 causes the image at the exit end of the light guide 3 to have radial unevenness on the observed surface. It is used for the purpose of reducing the appearance of

FIG. 3(A) shows an example of the arrangement of the illumination optical axis and the observation optical axis on the inner surface of the tube. When measuring a pipe weld as described above, the weld protrudes inward along the inner periphery of the pipe as shown in Figure 3 (B), but the edge of this protrusion should be carefully measured to avoid shading. For illumination, as shown in Figure 3 (A), the exit end of the illumination optical system and the observation optical system must be aligned so that the observation position by the observation optical system and the illumination position by the illumination optical system are on the same circumference. are arranged so that their incident ends are aligned in a straight line 7, so that the plane containing the observation optical axis and the illumination optical axis after being bent by the reflection mirror 5 is almost perpendicular to the observation optical axis before being reflected. It is preferable to bend it laterally using the reflecting mirror 5 as shown in FIG. With this arrangement, when the weld to be measured is brought to the center of the observation field, the illumination light illuminates the weld from directly above.

Next, in this embodiment, the reflecting mirror 5 is configured to be able to rotate around the observation optical axis, and FIGS. 4 and 5 show an example of the configuration. FIG. 4 shows an example in which the reflecting mirror 5, the observation optical system, and the illumination optical system are configured so that they can rotate together. That is, a fixed part 6 is provided at the tip of the observation device and can be held so as not to rotate with respect to the inner surface of the tube, and a motor 7 etc. built into this part connects the reflecting mirror 5, the observation optical system, and the illumination optical system. It is designed to rotate integrally with the built-in device body. In this case, the device body is made of a flexible material and is adapted to be twisted flexibly. Therefore, the entire circumference of the inner surface of the tube can be observed without moving the hand control unit. Of course, instead of being rotated by the motor 7 provided at the tip, if the observation device is continuous from the hand operation section to the tip of the device body, the hand side can be twisted to connect the reflecting mirror 5, observation optical system, and illumination. It is also possible to configure the optical system to rotate together. FIG. 5 shows an example in which only the reflecting mirror 5 can be rotated by the motor 7, but it goes without saying that even in this case, the light distribution characteristics and illumination efficiency as described above can be obtained. This method has similar effects and is useful not only for observing the inner surface of a tube but also for observing a plane located close to the outer surface of the observation device.

The specifications of the observation optical system shown in FIG. 1 are as follows.

Angle of view: 44° FNO: 12 Focal length: 6.828mn Moreover, the numerical data is as follows.

r + = 9999.0000 d, = 0.5600 n, = 1.88300
! /, =40.78r t = 3.8800 d, =3.4100 r, =9.7460 d r =2.500 n 2 =1.51633
ν2 =64.15r, = -12,1820 d, =0.2000 r s = 4.9200 d (=1 3000 r + = 9999.0000 d, =0.5000 r + = 9999.0000 dy =0. 8600 n, =1.51633
v, =64.15r r = 9999.0
000 (infrared cut filter) dl=1.50
00 n+ =1.52000 v, =74.0
Or*'=9999.0000 d, =0.3600 n, =1.51633r1
°=9999.0000 (aperture) dl. = 0.50
00 r 11 = 4,2430 cl,, = 1.3000 r 1+ = 23.6260 d, 2 = 1.0000 r 1h = -2,8360 d 1+”'0.6400 n + r 14 = 9999.0000 d ,,= 1.1000 64.15 64.15 64.15 23, 78 S G = 10.78 ν 3 ν 6 S 7 S 1.51633 1.51633 1.84666 n+ n s = 1.68870 r 1s = -7,2590 d15=1.0000 r, , = 9999.0000 (crystal) cl
,,=2.13 r l+ = 9999.0000 (crystal) d,,
=0.3 r, , -9999,0000 (crystal) d, , =1.
07 r,,=9999.0000 d,,=7.7180 n,o=1.68893
shi,,=31.06r,=9999.0000 d2゜=0.0020 r2l=9999.0000 d,=1.0820 n,,=1.68893
,,=31.06r2□=9999.0000 d,,=0.0010 r 2 ,=9999.0000 d t+=0.5000 n 12” 1.5165
5 shi12=64.15r t4=9999.
0000 In the above data, I"+ and dl nv1 represent the radius of curvature, spacing between surfaces, refractive index, and Abbe number of each lens, filter, etc., respectively.

FIG. 6 shows a second embodiment of the invention. In this embodiment, the entrance end O of the observation optical system and the exit end 2 of the illumination optical system are arranged on a line substantially perpendicular to the observation direction. The reflecting mirror 5 is connected to the observation optical system O as shown in FIG. 6(C).
The reflective surface 5a' facing the illumination optical system outside the effective diameter of the observation optical system is tilted at an angle with respect to the reflective surface 5a' facing the illumination optical system, so that the illumination optical axis approaches the observation optical axis. It is now possible to According to this embodiment, since the reflective surface used by the observation optical system and the reflective surface used by the illumination optical system can be substantially separated, the observation optical system due to the scattered light generated when the illumination light is reflected on the reflective surface Flare within the system can be effectively removed. Furthermore, according to this embodiment, as in the first embodiment, the observation section on the inner surface of the tube is illuminated from an oblique direction to the observation direction in the same plane as the longitudinal direction of the tube. It has the advantage that it is difficult to cast a shadow even if it protrudes inward.

Further, in the case of this embodiment, it is preferable to adopt a configuration in which the reflecting mirror 5, the observation optical system O, and the illumination optical system (2) are rotated integrally.

FIG. 7 shows a third embodiment of the invention. This embodiment is a modification of the second embodiment, in which the entrance end of the observation optical system 0 is arranged at the center of the apparatus main body, the exit ends of the illumination optical system (2) are arranged on both sides, and the observation optical system of the reflection mirror 5 is arranged. The reflecting surface 5a' facing the illumination optical system is tilted with respect to the reflecting surface 5a' facing the system, so that the illumination optical axis approaches the observation optical axis as in the second embodiment. According to this embodiment, since the surface to be observed is illuminated from both sides, there is an advantage that shadows are less likely to appear compared to the second embodiment. In this case as well, it is preferable to rotate the reflecting mirror 5, the observation optical system O, and the illumination optical system I together so that the entire circumference of the inner surface of the tube can be observed. Note that, like the second embodiment, this embodiment is useful not only for observing the inner surface of a tube but also for observing objects at a close distance such as those that are in close contact with the outer diameter of the main body of the apparatus.

FIG. 8 shows a fourth embodiment of the invention. This embodiment is a modification of the second embodiment, in which the reflective surface 5a' used by the observation optical system and the reflective surface 5a' used by the illumination optical system are completely separated, and both reflective surfaces overlap. This structure is designed to eliminate flare within the observation optical system caused by diffusely reflected light on a reflecting surface. That is, a convex lens 8 is used in place of the concave lens conventionally used as a component of the illumination optical system I, so that the illumination light flux emitted from the exit end is once narrowed down near the reflecting surface 5a' and then diverged. This is what I did.

Therefore, the effective area occupied by the illumination light on the reflective surface 5a' can be reduced, and as a result, it can be easily separated from the observation light. Note that the illumination optical system includes a convex lens 8 as in this embodiment.
If the light guide 3 is included, the end face of the light guide 3 may form an image on the surface to be observed, which may interfere with the observation. Therefore, in this embodiment, as shown in FIGS. 8(B) and 8(C), a single fiber 4' is interposed between the convex lens 8 and the light guide 3, so that the end face image of the light guide 3 can be seen clearly. This problem is solved by projecting the image onto the surface S to be observed.

FIG. 9 shows a fifth embodiment of the invention. In this embodiment, the observation optical system O is arranged at the center of the apparatus main body, and the illumination optical system I is arranged around it in a concentric ring shape, and the reflection mirror 5 has a reflection surface 5a facing the observation optical system. '
are formed into a flat plate shape, and a reflecting surface 5a' facing the illumination optical system is formed into an annular shape, and by tilting the reflecting surface 5a' with respect to the reflecting surface 5a', the illumination light is deflected toward the surface to be observed. This is how it was done. The entire circumference of the inner surface of the tube can be observed by rotating only the reflecting mirror 5 using the motor 7.
According to this embodiment, the reflecting mirror 5° illumination optical system I and the observation optical system 0 are arranged symmetrically with respect to the central axis of the observation device, so even if the reflecting mirror 5 rotates, the illumination state remains almost unchanged. It does not change and can always be observed in the optimal state. Of course, even in this embodiment, the reflecting mirror 5. It goes without saying that the illumination optical system I and the observation optical system O may be configured to rotate together.

FIG. 1O shows a sixth embodiment of the invention.

This embodiment differs from the fifth embodiment described above in that four illumination optical systems (1) are arranged at equal intervals on the same circumference, but is the same as the fifth embodiment in terms of effects. In the case of this embodiment, an illumination lens is not used in the illumination optical system, but a concave lens or a convex lens may be combined as necessary, or a deflection means such as a wedge prism may be combined as necessary.

FIG. 11 shows a seventh embodiment of the invention.

This embodiment is designed to reduce halation that occurs when the image at the exit end of the illumination optical system reflected from the surface to be observed enters the observation optical system when the surface to be observed is close to a mirror surface. Polarizing plates 8 and 9 are arranged in the optical system I and the observation optical system O, respectively, so that their vibration directions are substantially perpendicular to each other. Furthermore, as shown in FIG. 12, if a solid-state image pickup device 2 is used in the observation optical system O and a crystal filter 10 having a spatial frequency characteristic is inserted in the scanning direction of this device 2, this In order to prevent the spatial frequency characteristics from changing due to the inclusion of the polarizing plate 9, the vibration direction is rotated by 45 degrees with respect to the light separation direction of the first crystal filter 10 even when there are multiple crystal filters. The polarizing plate 9 is oriented in the same direction. The polarizing plate 8 inserted into the illumination optical system I is arranged so that its vibration direction is approximately perpendicular to the vibration direction of the polarizing plate 9. In this embodiment, since naturally polarized light is emitted from the illumination light source, this becomes linearly polarized light by passing through the polarizing plate 8, and is reflected by the reflecting mirror 5 to illuminate the observed surface S. If the surface is close to a mirror surface, the light will be reflected as linearly polarized light and its direction will be maintained. Therefore, this polarized light component is removed by the polarizing plate 9 when it enters the observation optical system. In this way, only the light component that should cause halation within the observation optical system is effectively removed.

In this case, the reflected light caused by scattering on the observed surface is considered to be natural light, but half of the incident light is cut off by the polarizing plate 9 of the observation optical system and the remaining light is sent to the solid-state image sensor 2 as observation light. It will be incident. This incident light is linearly polarized light tilted at 45 degrees with respect to the light separation direction of the crystal filter, so it is separated by the crystal filter while maintaining the same amount of light.
Shows specified low-pass characteristics. In this embodiment, the polarizing plate 8,
9 is placed in a crossed nicol system, the light effective for observation is 1/4 of the light from the light source, but it is effective because halation can be reduced to substantially zero. If the light source light itself is polarized, such as when a light emitting diode or semiconductor laser is used as the illumination light source, the plane of polarization can be tilted 90 degrees to the vibration direction of the polarizing plate 9 of the observation optical system. Although the same effect can be obtained without using the polarizing plate 8 of the illumination optical system, it is preferable to use the polarizing plate 8 in combination because the effect becomes even more remarkable. In addition, in recent years, in addition to conventional organic polarizing plates,
A glass polarizing plate has been developed in which a layer with polarizing properties is formed on the surface of the glass, but this plate also has excellent heat resistance, so there is no need to sandwich it between glass plates as in the past. It is convenient because it can be installed by attaching it as a thin plate to the exit surface of the illumination optical system and the entrance surface of the observation optical system. Furthermore, in order to create polarized light within the illumination optical system, the following method may be used in addition to using the polarizing plate 8 as described above. One method is to use a bundle of polarization-maintaining fibers with their polarization directions aligned as a light guide.

The other method uses a fiber bundle with low scattering, such as quartz fiber for communication, and installs a polarizing plate inside the light source.
This is a method of transmitting polarized light through a fiber bundle.

FIG. 13 shows an eighth embodiment of the present invention.

In this embodiment, the polarizing means such as the polarizing plate 8 provided in the illumination optical system can be rotated around the optical axis, so that the halation reduction effect can be changed depending on the state of the surface to be observed, so that it can be constantly observed. This embodiment differs from the seventh embodiment in that it is possible to obtain an easily observed image. Therefore, the same reflecting mirror and observation optical system as shown in FIG. 1I is used. First, in FIG. 13(A), a polarizing plate 8 is installed in front of the illumination lens 11, and its vibration direction is set at an angle of 90° with respect to the vibration direction of the polarizing plate 9 installed in the observation optical system. It is configured so that it can be rotated within the range that it includes. 13th
In Figure (B), a communication quartz fiber bundle is used as the light guide 3, and a polarizing plate 8 is placed between it and a single fiber 4'.
is arranged so that the polarizing plate 8 can be rotated relative to the quartz fiber bundle. FIG. 13(C) shows a configuration in which a polarizing plate 8 is arranged in a lens system within a light source and can be rotated. In FIG. 13(D), a polarization maintaining fiber is used as the light guide 3, and the light guide 3 is rotated (twisted) relative to the illumination lens 11 to change the polarization direction. In this case, each fiber composing the light guide 3 -
The books are arranged so that they vibrate in the same direction.

〔Effect of the invention〕

As described above (according to the present invention, the entire surface to be observed is always uniform).
In addition, bright illumination is possible, and even when the surface to be observed is close to a mirror surface, halation caused by specular reflection components can be effectively and appropriately removed, and an easy-to-see observation image can always be obtained. Therefore, according to the present invention, it is possible to provide an observation device that is particularly suitable for observing the inner surface of a tube.

[Brief explanation of drawings]

1(A) and 1(B) are configuration diagrams of the first embodiment of the observation device according to the present invention viewed from different directions, and FIG. 2(A)
) to (E) are diagrams showing mutually different configuration examples of the illumination optical system according to the present invention, FIG. 3(A) is an explanatory diagram showing an example of the arrangement of the illumination optical system and the observation optical system, and FIG. ) is a partial perspective view illustrating the state of the connection part of the tube, FIGS. 4 and 5 are explanatory views showing mutually different examples of the rotating mechanism of the reflecting mirror, and FIGS. 6 (A), (B), and (C ) is an end view showing the arrangement of the illumination optical system and the observation optical system in the second embodiment of the present invention, a side view and a perspective view of the reflecting mirror showing the arrangement relationship between the device main body part and the reflecting mirror, and FIG. A), (B) and (
C) is an end view showing the arrangement of the illumination optical system and observation optical system in the third embodiment of the present invention, a side view showing the arrangement relationship between the device main body part and the reflecting mirror, and a perspective view of the reflecting mirror;
FIGS. 8(A), (B), and (C) are explanatory diagrams showing the arrangement of the illumination optical system and the observation optical system in the fourth embodiment of the present invention, and the arrangement relationship between the illumination optical system and the reflecting mirror. An explanatory diagram showing the illumination optical system, the light distribution state at the reflective surface position, and the observed surface position, FIGS.
C) is a sectional view showing the arrangement relationship between the illumination optical system, the observation optical system, the reflection mirror, and the reflection mirror driving means in the fifth embodiment of the present invention, and an end view showing the arrangement relationship between the illumination optical system and the observation optical system; Perspective views of reflective mirrors, Figure 1O (A) and (
B) is a sectional view showing the arrangement relationship among the illumination optical system, observation optical system, reflection mirror, and reflection mirror driving means in the sixth embodiment of the present invention, and an end view showing the arrangement state of the illumination optical system and observation optical system. , 1A and 1B are explanatory diagrams showing the arrangement relationship between the observation optical system and the reflecting mirror in the seventh embodiment of the present invention, and an end view showing the arrangement state of the illumination optical system and the observation optical system. , FIG. 12 is a perspective view showing the configuration of the illumination optical system and observation optical system in the seventh embodiment, and FIGS. 13(A) and (B
), (C) and (D) are explanatory diagrams showing mutually different configuration examples of the illumination optical system in the eighth embodiment of the present invention, FIG. 14 is a diagram showing a typical conventional example of this type of observation device, 15th
Figures (A) and (B) are a schematic side view of another conventional example and a sectional view taken along the line b-b of the side view, and Figures 16 (A) and (B) are the illumination optical system and observation in another conventional example. FIG. 2 is an explanatory diagram showing the arrangement relationship between an optical system and a reflecting mirror, and an end view taken along line b-b of the explanatory diagram. l...Objective lens, 2...Solid-state image sensor, 3...
...Light guide, 4...Polarizing means, 5...
Reflection mirror 5a, 5a', 5a...reflection surface,
7... Motor 8.9... Polarizing element, 11...
...Illumination lens, ■...Illumination optical system, 0...
Observation optical system, S...surface to be observed. (A) Fig. 2 (B) (C) Fig. 3 Fig. 1P6 (A) (B) (C) Fig. 8 (A) Off Fig. (A) (B) (C) Fig. 13 Fig. 11 ( A) (B) 1?12 Figure 14 Figure 15 (A) (B) kJ1 mirror fang 46 (A) (B)

Claims (4)

[Claims] (1) In an observation device that is equipped with an observation optical system and an illumination optical system, and enables side observation by bending each optical axis with a reflecting mirror, there is a It is characterized by comprising a deflection element that bends the illumination optical axis to approach the observation optical system, and that the optical axis of the observation optical system and the illumination optical axis emitted from the deflection element are bent laterally by a common reflecting mirror. observation device. (2) In an observation device that is equipped with an observation optical system and an illumination optical system so that side observation can be performed by bending each optical axis with a reflecting mirror, a reflective surface that bends the optical axis of the observation optical system On the other hand, an observation device characterized in that a reflective surface that bends the optical axis of the illumination optical system is tilted and arranged so that the illumination optical axis approaches the observation optical axis. (3) Claim (1) or (3) characterized in that the observation optical system and the illumination optical system each include a polarizing element and are arranged so that their vibration directions are approximately at right angles. The observation device described in 2). (4) Claims characterized in that the observation optical system and the illumination optical system each include a polarizing element, and at least one of the polarizing elements is arranged so as to be rotatable around the optical axis. The observation device according to (1) or (2).