JP2012055561A - Endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize an endoscope capable of illuminating a front field of view and an entire field of view and obtaining a clear image not only for the entire field of view but also for the entire front field of view.
A primary mirror having an opening at the center and a rotationally symmetric reflection surface around the central axis of the opening, and a reflective surface having an opening at the center and rotationally symmetric around the central axis , A lens 3 provided at the opening of the secondary mirror 2, the primary mirror 1 and the secondary mirror 2, and a transparent cover 5 that transmits incident light 7a from the entire 360 ° lateral side 8 After the incident light 7a transmitted through the transparent cover 5 is reflected by the primary mirror 1 in the direction of the secondary mirror 2, the reflected light reflected by the secondary mirror 2 in the direction of the opening of the primary mirror 1 and the lens 3 are further transmitted. The imaging device 4 that images the transmitted light 7b that has been transmitted, and the light source 6 that irradiates light in the reverse direction of the direction in which the transmitted light 7b from the lens 3 is incident and toward the entire 360 ° side.
[Selection] Figure 2

Description

  The present invention relates to an endoscope having a front visual field and a 360-degree lateral peripheral field, and an illumination unit that illuminates both the visual fields.

  Endoscopes are used for in-vivo observation of humans and animals, or for in-tube inspections such as water and sewage pipes. Conventionally, an omnidirectional endoscope apparatus has been used for simultaneously observing and inspecting the entire circumferential field of view of an endoscope in a body cavity, a pipe, and the like. In a conventional omnidirectional endoscope apparatus, irradiation of an omnidirectional visual field from the operator's hand side (operation unit side) to an omnidirectional light receiving unit that receives illumination light from a light source from an omnidirectional visual field. (For example, refer to Patent Document 1).

Japanese Patent Laying-Open No. 2003-279862 (page 4, FIG. 4)

In the conventional omnidirectional endoscope apparatus, the omnidirectional light receiving unit becomes an obstacle because the illumination light is irradiated to the omnidirectional light receiving unit from the operator's hand side as described above. Therefore, there was a problem that a clear image of the entire front field of view could not be obtained.

  The present invention has been made in order to solve the above-described problems, and has a front field of view and an entire peripheral field of view, and illuminates both of these fields of view. An object is to realize an endoscope capable of obtaining an image.

  An endoscope according to the present invention has an opening in the center, a main mirror having a reflection surface that is rotationally symmetric around the central axis of the opening, and an opening in the center, around the central axis. A sub-mirror having a rotationally symmetric reflection surface, a lens provided at the opening of the sub-mirror, the main mirror and the sub-mirror, and a transparent cover that transmits incident light from the entire 360 ° side. And the incident light transmitted through the transparent cover is reflected by the primary mirror in the direction of the secondary mirror and then further reflected by the secondary mirror in the direction of the opening of the primary mirror and the lens. An imaging device that captures the transmitted light, and a light source that irradiates the light in the direction opposite to the direction in which the transmitted light from the lens is incident and toward the entire circumference of the lateral 360 degrees.

  According to the present invention, it is possible to illuminate the front field of view and the entire field of view and simultaneously observe the image of the front field of view transmitted through the lens by one imaging device and the image of the entire field of view reflected by the primary and secondary mirrors. In addition, it is possible to realize an endoscope that can obtain a clear image not only for the entire peripheral field of view but also for the entire front field of view.

1 is a perspective view showing an overall configuration of an endoscope according to Embodiment 1 of the present invention. FIG. It is sectional drawing which shows the structure of the endoscope in Embodiment 1 of this invention. It is sectional drawing which shows the structure of the endoscope in Embodiment 1 of this invention. It is sectional drawing which shows the structure of the endoscope in Embodiment 2 of this invention. It is sectional drawing which shows the structure of the endoscope in Embodiment 3 of this invention. It is a figure which shows refraction of the light in the endoscope in Embodiment 4 of this invention. It is sectional drawing which shows refraction | bending of the light which passes along the transparent cover end surface of the endoscope in Embodiment 4 of this invention. It is sectional drawing which shows a part of endoscope in Embodiment 4 of this invention.

Embodiment 1 FIG.
FIG. 1 shows a perspective view of the overall configuration of the endoscope according to Embodiment 1 for carrying out the present invention. In the drawings, the same reference numerals denote the same or corresponding parts, and this is common throughout the entire specification.
As shown in FIG. 1, the endoscope in the present embodiment includes a primary mirror 1, a secondary mirror 2, a lens 3 provided in an opening of the secondary mirror 2, an imaging device 4, a primary mirror 1, and It comprises a transparent cover 5 that supports the secondary mirror 2 and a light 6 as a light source.

Next, the configuration of the endoscope according to the present embodiment will be described with reference to the cross-sectional view of FIG.
As shown in FIG. 2, the endoscope according to the present embodiment has an opening at the center, and a main mirror 1 having a rotationally symmetric reflection surface around the center axis of the opening as a rotational symmetry axis. A secondary mirror 2 having an opening at the center and having a rotationally symmetric reflection surface around the same rotational symmetry axis as the rotational symmetry axis of the primary mirror 1, and a lens 3 installed in the opening of the secondary mirror 2 An imaging device 4 installed behind the primary mirror 1 (downward in FIG. 2), a transparent cover 5 that supports the primary mirror 1 and the secondary mirror 2 so as to face each other, and two end faces of the transparent cover 5 The light 6 is used as a light source for irradiating light to the end face on the primary mirror 1 side.

Next, the operation will be described.
Incident light 7a reflected from the secondary mirror 2 after passing through the transparent cover 5 and reflected from the primary mirror 1 from the entire peripheral visual field 8 on the side of the endoscope, ie, the side of the transparent cover 5, and the endoscope Any incident light 7 b that has passed through the lens 3 from the front visual field 9 of the mirror is incident on the imaging device 4. Thereby, the perimeter visual field 8 and the front visual field 9 can be always observed simultaneously.

  Of the illumination light 10 from the light 6, the illumination light 10a irradiated to the side of the endoscope illuminates the entire peripheral field. Also, the illumination light 10b that enters the end surface of the transparent cover 5 on the primary mirror 1 side, is guided by the transparent cover 5 and is emitted from the end surface on the secondary mirror 2 side illuminates the front field of view. Therefore, it is not necessary to prepare a light source for each of the entire field of view and the front field of view, and both the entire field of view and the front field of view can be illuminated simultaneously with only the light 6, and both the entire field of view and the entire front field of view are clear. Is obtained. In addition, since only the light 6 needs to be prepared, it is easy to reduce the size of the endoscope.

  Here, in FIG. 2, the light irradiated from the light 6 and transmitted through the transparent cover 5 to irradiate the front visual field is indicated by a dashed arrow (for example, 10b in FIG. 2). In addition, the light that irradiates the entire peripheral visual field from the light 6 (regardless of whether the light passes through the transparent cover 5) is indicated by a solid arrow (for example, 10a in FIG. 2). In addition, light that enters the imaging device 4 from the entire visual field 8 or the front visual field 9 is indicated by two-dot chain arrows (for example, 7a and 7b in FIG. 2). In addition, the light ray notation is not limited to FIG. 2, and the same applies to the drawings in the following embodiments.

  In FIG. 2, the direction of the light 6 is shown as being inclined with respect to the rotational symmetry axis of the primary mirror 1 and the secondary mirror 2, but this is not restrictive. For example, as shown in FIG. 3, the light 6 is behind the transparent cover 5, and the optical axis of the light 6 is different from that of FIG. 2 and is parallel to the rotational symmetry axis and forward (transparent from the light 6 in FIG. It may be facing the direction of the cover 5. The direction of the light 6 can be appropriately selected according to the observation target, the directivity of the light to be used, and the like as long as both the front visual field and the entire peripheral visual field can be irradiated. This is not limited to the present embodiment, and the same applies to the following embodiments.

  According to the present embodiment, it is possible to illuminate the entire visual field with the light 6 and illuminate the front visual field by guiding the light with the transparent cover 5. Accordingly, both the visual fields can be irradiated with the light 6 without preparing lights for illuminating the front visual field and the entire peripheral field, and a clear image can be obtained not only for the entire visual field but also for the entire front visual field. In addition, both the entire visual field and the front visual field can be always observed simultaneously by one imaging device 4. Furthermore, it is not necessary to prepare a separate light source for illuminating each field of view, and only the light 6 is required, so the endoscope can be easily downsized.

  Furthermore, although the case of two lights 6 is shown in FIG. 1, it is not limited to this. If it is not necessary to illuminate the entire 360 ° lateral view, the number of lights 6 can be reduced as appropriate. For example, the light 6 may be used for the purpose of observing only a part of a predetermined angle (for example, the inside of an opening angle of 90 degrees) and the front visual field at the same time among 360 degrees in the entire circumference of the pipe. Sometimes one is enough. Conversely, if it is desired to increase the amount of light, three or more lights 6 can be arranged. That is, the number of lights 6 can be appropriately selected according to the region to be observed and the illuminance of the light.

Embodiment 2. FIG.
FIG. 4 is a sectional view showing the configuration of the endoscope according to the second embodiment for carrying out the present invention. As shown in the figure, in the present embodiment, a diffuse reflection surface 11 is provided inside the transparent cover 5. In the figure, since the configuration other than the diffuse reflection surface 11 is the same as that of the first embodiment, the same reference numerals as those in FIG.

Next, the operation will be described.
As in the first embodiment, in the endoscope according to the present embodiment, incident light 7a reflected from the entire peripheral visual field 8 by the primary mirror 1 and the secondary mirror 2 and incident light transmitted from the front visual field 9 through the lens 3 7b enters the imaging device 4. Therefore, the entire peripheral visual field 8 and the front visual field 9 can be always observed simultaneously by one imaging device 4.
The illumination light 10b that is incident from the light 6 on the end surface of the transparent cover 5 on the primary mirror 1 side and is emitted from the end surface on the secondary mirror 2 side illuminates the front field of view. A part of illumination light (indicated by reference numeral 10a in FIG. 4) incident on the transparent cover 5 is diffusely reflected by the diffuse reflection surface 11 to illuminate the entire peripheral field. Thereby, both the front visual field and the entire peripheral field can be illuminated simultaneously by the illumination light of the light 6, and a clear image can be obtained in both the entire peripheral field and the entire front visual field. Furthermore, it is not necessary to prepare a separate light source for illuminating each field of view, and only the light 6 is sufficient. Therefore, it becomes easy to reduce the size of the endoscope.

The diffuse reflection surface 11 is formed by applying a material that diffuses and reflects to the transparent cover 5 (barium sulfate, magnesium carbonate, etc.), or forming a minute irregularity on the surface of the transparent cover 5 by sandblasting to provide a mirror surface. It can be formed by plating or by attaching a substance having a diffuse reflection surface such as aluminum oxide powder to the transparent cover 5.
Moreover, the installation location of the diffuse reflection surface 11 is not limited to the configuration shown in FIG. In FIG. 4, the diffuse reflection surface 11 can be installed as long as it is inside the transparent cover 5 except for between the line segment AB on the cross-sectional view, which is a portion where the entire peripheral visual field 8 and the transparent cover 5 overlap.

  According to the present embodiment, it is possible to illuminate the entire visual field with the light 6 and illuminate the front visual field by guiding the light with the transparent cover 5. Accordingly, both the visual fields can be irradiated with the light 6 without preparing lights for illuminating the front visual field and the entire peripheral field, and a clear image can be obtained not only for the entire visual field but also for the entire front visual field. In addition, both the entire visual field and the front visual field can be always observed simultaneously by one imaging device 4. Furthermore, it is not necessary to prepare a separate light source for illuminating each field of view, and only the light 6 is required, so the endoscope can be easily downsized.

Embodiment 3 FIG.
FIG. 5 is a sectional view showing the configuration of the endoscope according to the third embodiment for carrying out the present invention. As shown in the figure, in the present embodiment, a diffuse transmission surface 12 is provided outside the transparent cover 5. In the figure, since the configuration other than the diffuse transmission surface 12 is the same as that of the first embodiment, the same reference numerals as those in FIG.

Next, the operation will be described.
Similar to the first and second embodiments, the endoscope shown in FIG. 5 allows incident light 7a reflected by the primary mirror 1 and the secondary mirror 2 from the entire peripheral field 8 and incident light transmitted through the lens 3 from the front visual field 9. 7b can be observed all the time at the same time, so that the entire visual field and the front visual field can be observed simultaneously.

  Illumination light 10b that enters the end surface of the transparent cover 5 on the primary mirror 1 side and is emitted from the end surface on the secondary mirror 2 side illuminates the front field of view. A part of the illumination light incident on the transparent cover 5 is diffused by the diffusing and transmitting surface 12 to illuminate the entire peripheral field (reference numeral 10a in FIG. 5).

According to such a configuration, the entire visual field can be illuminated by the light 6 and the front visual field can be illuminated by being guided by the transparent cover 5. Accordingly, both the visual fields can be irradiated with the light 6 without preparing lights for illuminating the front visual field and the entire peripheral field, and a clear image can be obtained not only for the entire visual field but also for the entire front visual field. In addition, both the entire visual field and the front visual field can be always observed simultaneously by one imaging device 4. Furthermore, it is not necessary to prepare a separate light source for illuminating each field of view, and only the light 6 is required, so the endoscope can be easily downsized.
The diffuse transmission surface 12 can be created by forming minute irregularities on the outer peripheral surface of the transparent cover 5 by sandblasting.

Moreover, the installation location of the diffuse transmission surface 12 is not restricted to the structure shown in FIG. In FIG. 5, the diffuse transmission surface 12 can be installed on the outside of the transparent cover 5 except for between the line segments CD on the cross-sectional view that is a portion overlapping the entire peripheral visual field 8 on the outside of the transparent cover 5.

Embodiment 4 FIG.
In the above embodiment, the transparent cover 5 can be made of a material that transmits light, such as acrylic or glass. In general, these light-transmitting materials have a higher light refractive index than air. For example, when acrylic is used, as shown in FIG. 6, when light is emitted from the acrylic portion 14 into the air 15, the emission angle θ _out is larger than the incident angle θ _in .
Utilizing this property, by forming an inclined portion 5a having an inclined end surface on the side where the irradiation light from the transparent cover 5 is emitted (sub mirror 2 side), as shown in FIG. The illumination light 10b can be bent in a predetermined direction.

As shown in FIG. 8, when the end surface of the transparent cover 5 on the side of the secondary mirror 2 has a shape of an inclined portion 5a whose outer peripheral side is lower than the inner peripheral side, the illumination light 10b to the front visual field is bent inward. , Can illuminate nearby objects brightly. On the other hand, when the end surface of the transparent cover 5 on the side of the secondary mirror 2 is formed in the shape of the inclined portion 5a whose inner side is lowered, the illumination light 10b toward the front visual field is bent outward, so that the object is It can be illuminated over a wide area.
By appropriately setting the inclination angle of the inclined portion 5a in accordance with the material of the transparent cover 5 and the environment (in the air, in the liquid, etc.) in which the endoscope is used, It can be set to brighten the area close to the endoscope or to illuminate a wide area.

According to the present embodiment, it is possible to irradiate both fields of view with the light 6 without preparing lights for illuminating the front field of view and the entire field of view, and not only the entire field of view but also the entire front field of view is clear. An image is obtained. In addition, both the entire visual field and the front visual field can be always observed simultaneously by one imaging device 4. In addition, it is not necessary to separately prepare light sources for illuminating the respective fields of view, and only the light 6 is required, so that the endoscope can be easily downsized.
Furthermore, by setting the inclination angle of the inclined portion 5a of the transparent cover 5, the area irradiated with the illumination light in the front field of view according to the use environment of the endoscope and the observation target is set to a specific area close to A wide range can be set.

DESCRIPTION OF SYMBOLS 1 Primary mirror, 2 Secondary mirror, 3 Lens, 4 Imaging device, 5 Transparent cover, 5a Inclination part, 6 Light (light source), 7a, 7b Incident light, 8 Full view, 9 Front view, 10 Illumination light, 10a All Illumination light to the peripheral visual field, 10b Illumination light to the front visual field, 11 Diffuse reflection surface, 12 Diffuse transmission surface.

Claims (4)

A primary mirror having an opening in the center and having a reflective surface rotationally symmetric about the central axis of the opening;
A secondary mirror having an opening in the center and having a reflective surface rotationally symmetric about the central axis;
A lens provided in the opening of the secondary mirror;
A transparent cover that supports the primary mirror and the secondary mirror and transmits incident light from the entire 360 ° lateral side;
The incident light transmitted through the transparent cover is reflected by the primary mirror toward the secondary mirror, and then reflected by the secondary mirror toward the opening of the primary mirror and transmitted through the lens. An imaging device for imaging light;
An endoscope comprising: a light source that irradiates light in a direction opposite to a direction in which transmitted light from the lens is incident and on the entire side of the side 360 degrees. The endoscope according to claim 1, wherein a diffuse reflection surface that diffuses and reflects light is provided inside the transparent cover. The endoscope according to claim 1, wherein a diffusion transmission surface for diffusing and transmitting light is provided outside the transparent cover. The endoscope according to any one of claims 1 to 3, wherein an inclined portion is provided on an end surface of the transparent cover on the secondary mirror side.

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