JP3120445B2 - Objective of magnification observation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention comprises an observation apparatus main body and an objective tool, and reproduces an image taken by the objective tool on a display of the observation apparatus main body to perform enlarged observation of an object to be observed. In particular, the present invention relates to an objective device, particularly an objective device suitable for observing a narrow portion or the inside of a hole.

[Conventional technology]

The applicant has previously filed Japanese Patent Application Nos.
No. 26462 and Japanese Patent Application No. 1-273419 have proposed a magnifying observation apparatus.

This magnifying observation device is composed of an objective and an observation device main body, and takes the image of the objective by holding it on the side of the object to be observed.
This is displayed on the display of the observation device main body and observed, so that anyone can easily observe at a magnification of 50 to several thousand times without any skill or skill. .

[Problems to be solved by the invention]

However, this magnifying observation apparatus is not necessarily suitable for observation in a narrow portion such as the inside of a gear box or a gap between components arranged in a complicated manner due to the structure of the objective tool.

Therefore, an object of the present invention is to provide an objective of a magnifying observation apparatus that has a structure that can be inserted into a narrow portion and that can easily magnify and observe the inside of a narrow portion or a hole.

[Means for solving the problem]

Specifically, a light source formed in an annular shape, a condensing guide for condensing light from the light source and irradiating the light to an observation site, an optical system for capturing and transmitting an image of an object to be observed, and an optical system An image sensor for capturing the image transmitted by the system is provided. An objective lens having a light-collecting end face at the base end of the large-diameter portion and an irradiation end face at the front end of the small-diameter portion, and the optical system is built in the small-diameter portion of the condensing guide in order from the front end side. And an objective device of a magnifying observation apparatus comprising a rod lens of a distributed refractive index type, and such an objective device, wherein the light-collecting guide is formed of a plurality of vertically divided pieces. An objective is provided.

(Operation)

In this objective, the condensing guide efficiently condenses the light from the light source incident from the converging end face of the large-diameter portion on the base end side to the irradiation end face of the distal end of the small-diameter portion while efficiently condensing the light by the funnel shape. Then, the irradiation end surface is irradiated with strong irradiation light from the irradiation end face. On the other hand, an image of the object to be observed is captured via an objective lens built in the tip of the elongated small-diameter portion, the image is transmitted between the elongated small-diameter portions by a rod lens, captured by an image sensor, and output. To display on the display. Therefore, even if it is a narrow part, it can be easily observed by inserting the elongated small diameter part of the light-collecting guide into the observation target part.

Further, by forming the light-collecting guide of such an objective tool by a plurality of divided pieces divided in the vertical direction, the light-collecting efficiency is improved, and the molding is facilitated, so that a better molding accuracy is obtained. . That is, light incident from the light-collecting end face at an incident angle other than the fixed incident angle tends to leak to the outside. However, since each divided piece acts as a reflecting surface, this leak is prevented and the light-collecting efficiency is improved. In addition, it is quite troublesome to form a funnel-like shape that has an elongated small-diameter portion on the tip side and is continuous on a smooth curved surface as a whole, but it is quite troublesome, but it is formed by a vertically divided piece. By doing so, this trouble can be solved and the molding accuracy can be increased.

[Embodiment] An embodiment of the present invention will be described below.

As shown in FIG. 5, the objective 1 is formed of a main body 2 and a light-collecting guide 3 which is detachably attached to the main body 2 by screwing.

The main body 2 is cylindrical and includes therein an imaging unit 4 as shown in FIG. 1 and a light source 5 composed of a number of optical fibers 5f, 5f,... As shown in FIGS. And a cable 4c from the imaging unit 4 and an optical fiber 5f
The outside extension of the bundle is extended outside as a connection cable 6.

The image pickup unit 4 is for capturing an image transmitted by an optical system described later, and is a unit in which a CCD element 7 and other elements as an image pickup element are previously unitized for image pickup. Is sent to the observation device main body (not shown) via the cable 4c, and is displayed on the display there. A light-shielding cover S is attached to the end of the imaging unit 4, and a plurality of light-shielding stops i, i,
Are annularly protruded so as to form the minimum necessary optical path T. The formation of the minimum necessary optical path T by the light-shielding stops i, i,... Is extremely useful for obtaining a clear image.

The light source 5 is for guiding illumination light from an external light source (not shown). As shown in FIGS. 1 and 2, the light source 5 is composed of many optical fibers 5f, 5f,. Fiber 5
The end portions of f, 5f,... are planted in an annular holder 8 to form an annular shape.

The condensing guide 3 is for obtaining the strong illumination light required for observation at a high magnification by irradiating the illumination light from the annular light source 5 to the observation target site in a concentrated manner. It is made of a highly transparent synthetic resin such as (methacrylic resin). Specifically, as shown in FIG. 1 and FIG. 2, from the large diameter portion 9 on the proximal end side to the elongated small diameter portion 10 on the distal end side, the whole has a funnel-like shape that is continuous with a smooth curved surface. With such a funnel shape, the illumination light from the light source 5 incident from the light-collecting end face 11 at the base end of the large-diameter portion 9 is guided through the solid inside of the light-collecting guide 3 by total reflection. The laser beam is transmitted from the irradiation end face 12 at the tip of the small-diameter portion 10 so as to concentrate and irradiate the observation target site.

As shown in FIG. 2, the condensing guide 3 is formed by joining three vertically divided pieces 3p. The reason for forming the plurality of divided pieces 3p in this way is to improve the light-collecting efficiency and to facilitate the molding. That is, the light that can be transmitted by the total reflection inside the solid inside of the condensing guide 3 is the condensing end face.
Only light incident at a certain range of incident angle from 11 tends to leak the other light to the outside, but this leakage is caused by the joint surfaces 13, 13, 13 of each divided piece 3p acting as a reflective surface. It is prevented and the light collection rate is improved. Also, it is quite troublesome to form the funnel-shaped shape as described above by one-time molding. However, if this is formed from the divided pieces 3p, this trouble can be solved, and the mold design and molding can be performed. This is more advantageous for ensuring accuracy.

Further, the condensing guide 3 incorporates an optical system 16 in which an objective lens 14 and a rod lens 15 are arranged in order from the tip side inside the small diameter portion 10. The cover glass 17 is provided on both the front end of the objective lens 14 and the rear end of the rod lens 15.

The objective lens 14 is a distributed index lens similar to the rod lens 15 described later, but the rod lens 15 simply transmits an image, but an enlarged image can be obtained at a predetermined design magnification. .

The rod lens 15 is a distributed index type, that is, an image transmission body of a type in which the refractive index is distributed in a parabolic shape from the central axis toward the outer periphery, and has a cylindrical rod shape. Then, as shown in FIG. 4, light is propagated through a sine-curve optical path corresponding to the distribution state of the refractive index, so that the image is transmitted as it is from the incident end face 18 side to the emission end face 19 side. I have.

By the way, such a rod lens is conventionally known, but conventionally, an image is formed on the exit end face, and the image formed on the exit end face is further passed through an eyepiece including a plurality of convex lenses. In general, the rod lens 15 is used for observation, but the rod lens 15 forms an image before the emission end face 19, and the light receiving surface 7f of the CCD element 7 faces the image formation position. By adopting such a configuration, the above-mentioned eyepiece can be dispensed with, the problem of chromatic aberration can be solved, the structure can be simplified, and the exit end face can be simplified.
It is not affected by the polishing accuracy of 19 or the attached dust, and a high quality image can be obtained stably.

Such an image formed outside the emission end face is obtained by setting the length of the rod lens 15 to (n + X) × the pitch length P of the meandering cycle of the optical path.
P (m / m) (n = 0, 1, 2, 3,...; X is about 0.8)
It is obtained by setting to the length. Then, as shown in FIG. 4, the image plane outside the emission end face appears on the intersection of the tangent to the optical path curve interrupted by the emission end face 19 having such a length.

In the above-described embodiment, the configuration of image formation outside the exit end surface of the rod lens is combined with the light collecting guide 3. However, such a combination is not necessarily required. For example, an optical fiber may be used instead of the light collecting guide 3. May be used as appropriate. In addition, although a group of optical fibers 5f, 5f,... Is used to form an annular light source, minute light emitting sources may be arranged in an annular shape instead.

〔The invention's effect〕

Since the objective according to the present invention is as described above, it has the following effects.

(A). Since a light-collecting guide having a funnel shape is provided, and a rod lens for image transmission is provided inside the small-diameter portion of the light-collecting guide, the narrow narrow-diameter portion of the light-collecting guide is inserted into a portion to be observed to be narrowed. Even in the part, the magnified observation can be performed more effectively in a clear state with strong illumination light.

(B). By forming the light-condensing guide with a plurality of divided pieces, the light-condensing rate is further improved, and the moldability is improved, so that better molding accuracy is obtained.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a main part of the objective tool, FIG. 2 is a schematic perspective view showing a relationship between a light source and a condensing guide, and FIG. 3 is a view seen from a direction indicated by an arrow III in FIG. FIG. 4 is a schematic side view showing a light transmission state in the rod lens, and FIG. 5 is a schematic side view of the objective tool. DESCRIPTION OF SYMBOLS 1 ... Objective tool 3 ... Condensing guide 5 ... Light source 7 ... CCD element (imaging element) 7f ... Light receiving surface 9 ... Large diameter section 10 ... Small diameter section 11 ... Condensing end face 12 ... Irradiation End surface 14 Objective lens 15 Rod lens 16 Optical system 18 Input end surface 19 Output end surface

Claims (2)

(57) [Claims] An annular light source, a condensing guide for condensing light from the light source and irradiating the light to an observation site, an optical system for capturing and transmitting an image of an object to be observed, and an optical system An objective tool of a magnifying observation device equipped with an imaging device for capturing an image transmitted by a system, wherein the light-collecting guide has a smooth curved surface from the large-diameter portion on the proximal side to the elongated small-diameter portion on the distal end. In the form of a continuous funnel, it is formed of a plurality of divided pieces divided in the vertical direction.It has a light-collecting end face at the base end of the large-diameter part, and has an irradiation end face at the tip of the small-diameter part. Objective of the magnifying observation device. 2. The objective of the magnifying observation apparatus according to claim 1, wherein the optical system includes an objective lens and a distributed refractive index type rod lens which are sequentially incorporated inside the small diameter portion of the light-collecting guide from the distal end side. Utensils.