JPH06258527A - Light condensing rod built-in type optical fiber device - Google Patents

Abstract

PURPOSE:To obtain a light condensing rod built-in type optical fiber device which can be used as a substitute for a fiber bundle for illumination, whose diameter is small, which is light in weight, and which is excellent in the light incident efficiency. CONSTITUTION:An optical fiber 21 is exposed by peeling its coating 26 at one end on the incident side 12 of an optical fiber cord 11, and the end face of a tapered transparent rod 22 having a small-diameter part 24 and a large- diameter part 23 on the small diameter part 24 side is welded and connected to the end face of the optical fiber 21, and the outside surface of the rod 22 is covered with a coating 26 made of a material having lower refractive index than the outside surface of the rod 22. Furthermore, an envelope sleeve 21, an inner sleeve 28, and an outer sleeve 29 are attached to the rod 22 so as to protect it. The light is made incident from the end face on the large-diameter part 23 side of the rod 22, condensed by the rod 22, made incident on the end face of the optical fiber 21, propagated in the optical fiber cord 11, and projected from an FC connector type projection part 13 at the other end.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber device used for illumination or the like, and more particularly to an optical fiber device with a built-in collecting rod.

[0002]

2. Description of the Related Art Conventionally, a fiber bundle has been used for illuminating an observation region near the tip of an industrial or medical fiberscope. This fiber bundle is made by bundling a large number of thin optical fibers and is very fragile due to its structure. Therefore, conventionally, the outer peripheral portion of the fiber bundle is protected by being covered with a flexible stainless tube or the like.

[0003]

However, in the conventional fiber bundle, since a large number of small-diameter optical fibers are bundled as described above and a protective tube is required for this bundle,
As a whole, the outer diameter becomes large and heavy, and there is a problem that maneuverability is poor. Further, since the optical fibers are bundled, the light escapes from the gap, so that the incident efficiency of light is poor, and the aperture at the incident end must be increased to obtain the desired illuminance.

In view of the above, the present invention provides an optical fiber device with a built-in condensing rod, which can be used in place of the conventional fiber bundle for illumination, has a small diameter and is lightweight, and has a good light incident efficiency. The purpose is to do.

[0005]

In order to achieve the above object, an optical fiber device with a built-in condenser rod according to the present invention has a tapered transparent rod having a small diameter portion and a large diameter portion. The end face of the rod on the side of the small diameter portion is joined to the end face on the incident side of a single optical fiber, and the outer face of the rod is covered with a material having a refractive index lower than that of the rod. Has become.

[0006]

A transparent rod is coupled to the incident end surface of a single optical fiber, and light is incident on one end of the optical fiber through this transparent rod. The transparent rod has a small-diameter portion and a large-diameter portion and is formed in a taper shape. The end face of the optical fiber is coupled to the end face on the small-diameter portion side, and light is incident from the end face on the large-diameter portion side. . Therefore, the light incident on the transparent rod is condensed as it propagates to the small diameter portion side, and is incident on one end of the optical fiber in the condensed state.
Since the outer surface of the transparent rod is covered with a coating of a material with a lower refractive index than that, the light that has entered the transparent rod is focused without leaking from the transparent rod, enabling efficient incidence of light. Become. Since the optical fiber is a single optical fiber, it has a small diameter and light weight, is excellent in flexibility, and is very easy to handle.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a sectional view schematically showing an embodiment of the present invention. As shown in this figure, in the optical fiber device with a built-in condensing rod according to the present invention, an entrance portion 12 is formed at one end of an optical fiber cord 11 having a single optical fiber 21, and an exit portion 13 is formed at the other end. Are formed. In this embodiment, the optical fiber 21 is made of, for example, a silica glass fiber having a relatively large outer diameter of 1 mm, but in addition to the silica glass fiber, a multi-component fiber or a plastic fiber can be used. The outer diameter is not limited to the above. The emitting portion 13 is configured as an FC connector type, but a sleeve type emitting portion 14 is also possible and may be another type.

In the incident portion 12, the coating of the optical fiber cord 11 is peeled off at the tip to expose the optical fiber 21, and is fused (or bonded) to one end of the transparent rod 22. That is, the transparent rod 22 is formed in a tapered shape with the large diameter portion 23 and the small diameter portion 24, and the end face of the small diameter portion 24 is fused (or bonded) to the end face of the optical fiber 21. There is. The rod 22 is made of a glass material or a plastic material. The outer surface of the transparent rod 22 is covered with a coating 26 made of a material having a refractive index lower than that of the rod 22, for example, silicon oil.

An outer sleeve 27, an inner sleeve 28, and an outer sleeve 29 are used to protect the transparent rod 22, the optical fiber 21, and the fused portion 25 thereof. That is, the inner sleeve 28 is covered around the optical fiber 21, the small-diameter portion 24 of the transparent rod 22, and the fusion-bonded portion 25, and is fixed with the adhesive 31. An outer sleeve 29 is attached to the large diameter portion 23 side of the transparent rod 22 and fixed with an adhesive 34. The outer sleeve 27 includes the inner sleeve 28, the outer sleeve 29, and the coating 26.
Are fixed by adhesives 32 and 33 so as to cover the outer periphery of the.

The optical fiber device with a built-in condensing rod according to one embodiment of the present invention is configured in this way, and light is incident from the end of the transparent rod 22 of the incident part 12 on the side of the large diameter part 23, Light is emitted from the emitting portion 13 (14) formed at the other end of the fiber cord 11 to illuminate.

In this case, since the transparent rod 22 has the large diameter portion 23 on the incident side, a large amount of light can be easily incident. In addition, the light incident on the rod 22 has a tapered shape.
The light is condensed in 2 and exits from the end face of the small diameter portion 24 and enters the end face of the optical fiber 21. And since the periphery of the transparent rod 22 is covered with a coating having a lower refractive index than that,
The light that has entered the rod 22 is focused on the end face of the small diameter portion 24 without going outside. Therefore, the light can be efficiently incident on the incident side end surface of the optical fiber 21.

The optical fiber cord 11 is not a bundle of a large number of optical fibers but a single optical fiber 2
Since it has No. 1, it is thin and lightweight as a whole, and is also excellent in flexibility. Therefore, it is very easy to handle it by bending it.

FIG. 2 shows only the incident portion 12 of another embodiment. In this example, as shown in FIG. 2, a connector 41 is attached to the incident side end of the optical fiber cord 11, and by coupling a receptacle 42 to this connector 41, the same taper as that shown in FIG. The transparent rod 22 and the end of the optical fiber 21 in the optical fiber cord 11 are coupled to each other. As the connector 41, each type such as FC type and SC type can be used.

In the receptacle 42, the same tapered transparent rod 22 as that shown in FIG. 1 is housed.
That is, the transparent rod 22 has a large diameter portion 23 and a small diameter portion 2.
And 4 are formed in a tapered shape. The outer surface is covered with a coating 26 made of a material having a refractive index lower than that of the rod 22, for example, silicon oil, as in the case of FIG. These transparent rods 2
2. The coating 26 includes an inner sleeve 48, an outer sleeve 49,
These outer envelope sleeves 47 are covered and the adhesive 5
Bonded at 1-54.

By coupling this receptacle 42 to the connector 41, the tip surface of the optical fiber 21 in the optical fiber cord 11 exposed from the tip of the ferrule 43 is coupled to the end surface of the small diameter portion 24 of the transparent rod 22. be able to. Therefore, in this state, if the light is incident from the end surface of the transparent rod 22 on the large diameter portion 23 side, the light can be efficiently incident on the incident end surface of the optical fiber 21 as in FIG.

[0016]

As described above, according to the optical fiber device with a built-in condensing rod of the present invention, there is a great effect in that the diameter and the weight of the optical fiber device are smaller than those using the conventional fiber bundle. Can be obtained and is easy to handle. In addition, the incident efficiency of light is also excellent. Furthermore, when combined with an image fiber to form an endoscope,
Taking advantage of the small diameter and light weight, it is easy to increase the length as a whole. Even when used separately from the endoscope, it can be easily connected to the endoscope via a connector.

[Brief description of drawings]

FIG. 1 is a side view showing a part of a cross section of an embodiment of the present invention.

FIG. 2 is a side view showing a part of another embodiment in section.

[Explanation of symbols]

11: Optical fiber cord 12; Incident part 13; FC connector type emission part 14; Sleeve type emission part 21; Optical fiber 22; Transparent rod 23; Large diameter part 24; Small diameter part 25; Fused part 26; Coating 27, 47; outer sleeve 28, 48; inner sleeve 29, 49; outer sleeve 31, 32, 33, 34, 51, 52, 53, 54; adhesive agent 41; connector 42; receptacle 43; ferrule

Claims (1)

[Claims] 1. A single optical fiber, and a tapered transparent rod having a small-diameter portion and a large-diameter portion in which an end face of the incident side of the optical fiber is joined to an end face of the small-diameter portion, An optical fiber device with a built-in condensing rod, comprising: a coating of a material having a refractive index lower than that of the rod, the coating covering the outer surface of the rod.