JP2003270454A - Bundle fiber and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bundle fiber having favorable transmission characteristics in a broad wavelength band. <P>SOLUTION: The bundle fiber is constituted by mixing coated optical fibers having a plurality of transmission wavelength bands. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bundle fiber and a method of manufacturing the bundle fiber, and more particularly to control of output light amount distribution thereof.

[0002]

2. Description of the Related Art A bundle fiber is made by bundling several to several thousand optical fiber strands and bonding and polishing the end portions thereof, and is widely used for illumination and energy transmission. Both end surfaces of the bundle fiber are usually fixed with sleeve-shaped metal fittings, etc., but flexibility is maintained in the middle part, and it is possible to increase the light receiving area and the emitting area while maintaining the spatial freedom. Is possible,
It is being used in various fields.

[0003]

Conventionally, an optical fiber strand used in a bundle fiber for transmitting ultraviolet rays has a characteristic that the loss increases near a wavelength of 900 nm which is a near infrared region. There is a problem that it is not suitable for use. It is considered that this is because the optical fiber contains a large amount of OH groups, so that the loss increases due to water absorption, and the loss near the wavelength of 900 nm sharply increases as shown in the wavelength loss characteristic in FIG. ing.

Further, as shown in the wavelength loss characteristic of FIG. 7, the optical fiber strand used in the conventional bundle fiber for transmitting visible and near infrared rays has a wavelength at which the loss increases at a wavelength of 400 nm or less in the ultraviolet region. Since it has a loss characteristic and its transmittance in the ultraviolet region is poor, there is a problem that it is not suitable for use in the ultraviolet region.

Therefore, it has not been possible to obtain a bundle fiber that can be used in a wide wavelength band. The present invention has been made in view of the above circumstances, and an object thereof is to provide a bundle fiber having good transmission characteristics in a wide wavelength band.

[0006]

In view of the above, the present invention is characterized in that a bundle fiber is constructed by mixing optical fiber strands having a plurality of transmission wavelength bands.

According to this structure, a wide transmission wavelength band can be formed complementarily by using optical fiber strands having a plurality of transmission wavelength bands, and a bundle fiber with good transmission characteristics can be formed. Becomes

It is desirable that the optical fiber element wire having a plurality of transmission wavelength bands is a mixture of an ultraviolet ray transmitting optical fiber element and a visible light and near infrared ray transmitting optical fiber element.

Preferably, the optical fiber for transmitting ultraviolet rays has a transmission loss of 500 dB at a wavelength of 250 nm.
/ Km or less, and the optical fiber wire for transmitting visible light and near infrared rays has a transmission loss of 50d at a wavelength of 2000 nm.
It is characterized by being B / km or less.

Preferably, the bundle fiber has a light transmittance of 30% / m at a wavelength of 250 nm,
And the light transmittance at a wavelength of 2000 nm is 30% / m.
And is characterized in that.

Preferably, the optical fiber wire having a plurality of transmission wavelength bands is provided with a coating of a different color for each transmission band.

By forming a coating of a different color for each transmission wavelength band, it becomes possible to uniformly arrange optical fiber element wires having respective characteristics.

Preferably, the optical fiber element for transmitting ultraviolet rays has a clad made of quartz to which fluorine is added, and the optical fiber element for transmitting visible light and near infrared rays is added with germanium oxide. It is characterized by being composed of quartz.

Desirably, a step of forming an optical fiber element wire having a coating of a different color for each transmission wavelength band, a step of mixing the optical fiber element wires and arranging them so that the color distribution becomes uniform, And bundling and fixing the arrayed optical fiber strands.

According to this structure, different color coatings are formed for the respective transmission wavelength bands, and the color distributions are arranged so that the color distribution is uniform while observing the color dispersion. It is possible to efficiently form the bundle fiber.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. Embodiment 1 In the bundle fiber of the first embodiment of the present invention, as shown in the transmittance characteristics in FIG. 1, the optical fiber element wire having the plurality of transmission wavelength bands is for transmitting ultraviolet rays shown by a curve c1. The optical fiber element wire and the optical fiber element for transmitting visible light and near infrared rays shown by the curve c2 are mixed to form a broadband bundle fiber as shown by the curve a.

As shown in FIG. 2, this broadband fiber bundle comprises an optical fiber element wire 1 for transmitting ultraviolet light, which is called SF-180 having a purple coating, and GF-having a red coating. The optical fiber strands 2 for transmitting visible light and near infrared rays, which are designated as 180, are arranged alternately and 5
Twenty-five pieces were bundled and the outer circumference was covered with a coating layer 3 made of polypropylene resin to have a bundle diameter of 5 mm. As shown in the enlarged view of FIG. 3 (a), this ultraviolet transmitting optical fiber element wire 1 has an outer diameter of 190 (± 9) μ in which the core is made of pure quartz and the clad is made of fluorine-added quartz.
The glass fiber 1C of m is coated with a purple resin 1V to form an optical fiber element wire 1 having an outer diameter of 240 (± 10) μm. Further, as shown in an enlarged view of FIG. 3B, the optical fiber element 2 for transmitting visible light and near infrared rays has an outer diameter of 190 (±) in which the core is made of germanium oxide-doped quartz and the clad is made of pure quartz. 9) The glass fiber 2C of μm is covered with the red resin 2R to have an outer diameter of 240 (± 1
0) The optical fiber strand 1 of μm is formed. This optical fiber for transmitting ultraviolet rays has a wavelength of 250n.
The transmission loss at m is 500 dB / km or less, and the optical fiber for transmitting visible light and near infrared rays has a wavelength of 200
Those having a transmission loss at 0 nm of 50 dB / km or more were mixed at a ratio of 1: 1 and used. However, the transmittance in each wavelength band can be adjusted by changing the mixing ratio depending on the application.

Next, the manufacturing process of this broadband fiber bundle will be described. This broadband fiber bundle
As shown in the flowchart of the manufacturing method in FIG. 4, a total of 525 optical fiber strands including an optical fiber strand 1 for transmitting ultraviolet rays, an optical fiber strand 2 for transmitting visible light and near infrared rays are prepared (step 101). ). Here, the ultraviolet transmitting optical fiber strand 1 is covered with a purple resin 1V, and the visible light near infrared transmitting optical fiber strand 2 is covered with a red resin 2R. Then, the scale is measured and the product is cut into a desired size (step 102). Then, the ultraviolet transmitting optical fiber strand 1 and the visible light near infrared transmitting optical fiber strand 2 are mixed, randomized and bundled (step 103). Then, the coating on the incident side end and the emitting side end is peeled off with sulfuric acid (step 104). Thereafter, the ultraviolet ray transmitting optical fiber element wires 1 and the visible light and near infrared ray transmitting optical fiber element wires 2 are arranged so that the resin color arrays are diagonally arranged alternately on the incident side and the emission side. Arrange them alternately and attach a stainless steel (SUS) cylindrical sleeve (Step 1
05), the end surface is mirror-polished (step 106). Then, plug assembly is performed (step 107), optical characteristics are inspected (step 108), product labels are attached, and shipping packaging is performed (step 109).

In this way, a bundle fiber having a transmittance of 30% / m at a wavelength of 250 nm and 30% / m at a wavelength of 2000 nm can be obtained.

The transmittance of this bundle fiber is calculated by the following equation. The theoretical transmittance of the bundle fiber using the optical fiber strand 1 for ultraviolet ray transmission called SF-180 is obtained by the following formula,
The point transmittance in nm was 63.0% / m. In the case of SF-180, φ5 bundle, 525 cores, L = 1 m, the point transmittance in the used wavelength band of the bundle fiber is obtained by the following equation. T = A × B × (1−C) ² × 100% / m Here, each parameter is T: transmittance (%), A: core filling rate, B: transmittance per unit length of fiber, C : Reflectance of end face, C = ((n ₁
−n ₀ ) / (n1 + n0)) ² , n ₁ = core refractive index, n ₀ :
Indicates the refractive index of air. However, A = π · (dc / 2) ² · N
/ S where dc: core diameter (mm), N: number of fiber strands (pieces), S: bundle end area (mm ² ), and
B = 10 ^{− (} α ^{/ 10 ) / (L / 100)} , where d: fiber transmittance (dB / km), L: fiber length (m). The numerical value was substituted into the above equation to calculate the point transmittance of the bundle fiber at a wavelength of 250 nm, and the result was 63.0%.
The theoretical transmittance of the bundle fiber using the optical fiber element 21 for transmitting visible light and near infrared rays, which is called GF-180 having a red coating, is calculated as shown in the above equation, The point transmittance at 2000 nm was 69.3% / m.

Then, the transmittance of the bundle fiber obtained by mixing them was measured in the same manner.
It was 5% / m and 34.6% / m, and exceeded 30% / m. If the transmittance is 30% / m or more, it can be used for most applications, and the bundle fiber according to the present invention is considered to be good.

As an arrangement of the present invention, as shown in FIG. 5, the ultraviolet transmitting optical fiber strands 1 and the visible light and near infrared transmitting optical fiber strands 2 may be alternately arranged one by one. Good.

Further, in the above embodiment, the optical fiber element for transmitting ultraviolet rays and the optical fiber element for transmitting visible and near infrared rays are mixed and arranged. However, Ar having a wavelength λ = 193 nm is arranged.
It has two or more different band characteristics, such as a combination of excimer for F laser, KrF laser with wavelength λ = 248 nm, and optical fiber strand for transmitting ultraviolet light and / or optical fiber strand for transmitting visible / near infrared light. It is possible to mix and use optical fiber strands.

Further, a bundle fiber having a desired transmittance can be obtained by changing the mixing ratio of the optical fiber element for transmitting ultraviolet rays and the optical fiber element for visible light and near infrared rays according to the required characteristics.

[0025]

As described above, according to the bundle fiber of the present invention, wide wavelength band characteristics can be obtained. Further, according to the method for manufacturing a bundle fiber of the present invention, it is possible to obtain a bundle fiber having a desired wide wavelength band characteristic extremely efficiently.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a bundle fiber according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the bundle fiber according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram showing an optical fiber element wire used in the embodiment of the present invention.

FIG. 4 is a flowchart showing a manufacturing process of the bundle fiber according to the first embodiment of the present invention.

FIG. 5 is a diagram showing a bundle fiber according to a second embodiment of the present invention.

FIG. 6 is a diagram showing a transmittance characteristic of an optical fiber strand for transmitting ultraviolet light.

FIG. 7 is a diagram showing a transmittance characteristic of an optical fiber wire for transmitting visible light and near infrared rays.

[Explanation of symbols]

1 Optical fiber strand for UV transmission 2 Optical fiber wire for transmitting visible light and near infrared rays 3 coating layer

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[Procedure amendment]

[Submission date] March 28, 2002 (2002.3.2)
8)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 4

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

Preferably, the bundle fiber has a light transmittance of 30% / m or more at a wavelength of 250 nm and a light transmittance of 30% at a wavelength of 2000 nm.
/ M or more .

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shishido Shihiko             Sumitomoden 1 Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa             Ki Industry Co., Ltd. Yokohama Works F term (reference) 2H046 AA03 AB08 AB12 AZ01

Claims (7)

[Claims] 1. A bundle fiber comprising a mixture of optical fiber strands having a plurality of transmission wavelength bands. 2. The optical fiber strand having a plurality of transmission wavelength bands is a mixture of an optical fiber strand for transmitting ultraviolet light and an optical fiber strand for transmitting visible light and near infrared light. Bundle fiber described in. 3. The ultraviolet transmitting optical fiber element has a transmission loss of 500 dB / km or less at a wavelength of 250 nm, and the visible light and near infrared transmitting optical fiber element is
The bundle fiber according to claim 2, wherein the transmission loss at a wavelength of 2000 nm is 50 dB / km or less. 4. The bundle fiber has a wavelength of 250 n.
m has a light transmittance of 30% / m and a wavelength of 2
The bundle fiber according to any one of claims 1 to 3, wherein the light transmittance at 000 nm is 30% / m. 5. The bundle fiber according to claim 1, wherein the optical fiber strand having a plurality of transmission wavelength bands is provided with a coating of a different color for each transmission band. . 6. The ultraviolet transmitting optical fiber element wire has a clad made of quartz to which fluorine is added, and the visible light near infrared ray transmitting optical fiber element wire has a core to which germanium oxide is added. 6. The bundle fiber according to claim 1, wherein the bundle fiber is made of quartz. 7. A step of forming optical fiber strands having coatings of different colors for respective transmission wavelength bands, a step of mixing the optical fiber strands and arranging them so that a color distribution becomes uniform, And a step of bundling and fixing the arrayed optical fiber strands.