JPH0843646A - Light transmission tube - Google Patents

Abstract

PURPOSE:To provide a light transmission tube which is less deteriorated in a core even after long-term use, has stable optical transmission performance and prevents deterioration and temp. rise of an object to be irradiated by exit light by forming a IR reflection or absorption film and/or UV reflection or absorption film on one end face of a sealing plug. CONSTITUTION:This light transmission tube includes a transparent core 1, a tubular clad 2 which has a refractive index lower than the refractive index off this core and coats the transparent core 1 and sealing plugs 3a, 3b which are fitted into the apertures at both ends of the clad 2. The sealing plug 3a on the light incident side is formed out of a transparent material and the other sealing plug 3b is formed out of the transparent material as well when the core is irradiated with the light from the other sealing plug 3b. Further, IR reflection or absorption films 4 and/or UV reflection or absorption films 4 are formed on, at least, one end face of the light incident side sealing plug 3a and preferably on, at least, one end face of the exit slight sealing plug 3b when the light exit side sealing plug 3b is formed to be transparent as well and the light is emitted therefrom.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical transmission tube capable of preventing deterioration of a core and exhibiting stable optical transmission performance for a long period of time.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
An optical transmission tube including a transparent core and a tubular clad having a lower refractive index than the transparent core and covering the core is used for various optical transmission applications. in this case,
Solid and liquid cores are known, but the core has a diameter of 3 mm in order to efficiently transmit a large amount of light.
A large diameter of at least mm is used.

However, according to the study of the present inventors, in such an optical transmission tube having a large diameter core, the core is deteriorated and the optical transmission performance is apt to be deteriorated when it is used for a long period of time. It was In addition, the light emitted from the light transmission tube often causes a temperature rise on the object to be irradiated, or deteriorates the object to be irradiated.

The present invention has been made in view of the above circumstances.
An object of the present invention is to provide an optical transmission tube that has little deterioration of the core even after long-term use, has stable optical transmission performance, and can prevent deterioration of an irradiated object and temperature rise due to emitted light. .

[0005]

Means for Solving the Problems and Actions The inventors of the present invention have conducted extensive studies in order to achieve the above object, and as a result, the deterioration of the core was caused by the infrared rays and the ultraviolet rays passing through the core, whereby the core absorbed heat. In addition, due to changes in the molecular structure, temperature rise and deterioration of the irradiated object, infrared rays and ultraviolet rays that pass through the core together with visible light in the light incident on the core project the irradiated object. We found that it was due to that, and attached a transparent sealing stopper to the open end of the tubular cladding,
By forming an infrared reflection or absorption film or an ultraviolet reflection or absorption film on at least one end face of this transparent sealing stopper, or by incorporating an infrared absorber or an ultraviolet absorber in this transparent sealing stopper, When the invasion of infrared rays and ultraviolet rays is blocked, deterioration of the core is prevented as much as possible, stable optical transmission performance is exhibited for a long time, and infrared rays and ultraviolet rays can be projected onto the irradiated object as much as possible. Being prevented by
We have found that the temperature rise and deterioration of the irradiated object can be reduced. In this case, it is known to attach a sealing plug to the open end of the clad, and especially when the core is liquid, the sealing plug is indispensable to prevent leakage of the core,
The above object is achieved by forming an infrared reflection or absorption film, an ultraviolet reflection or absorption film, or by containing an infrared absorption agent or an ultraviolet absorption agent in this sealing plug.

That is, according to the present invention, (1) a transparent core, a tubular clad having a refractive index lower than that of the core and covering the core, and a tubular clad, which are fitted in the openings at both ends of the clad, respectively.
In an optical transmission tube including at least a light-incident side sealing plug formed of a transparent material, an infrared-reflecting or absorbing film and / or an ultraviolet-reflecting or absorbing film is provided on at least one end surface of the light-incident-side transparent sealing plug. The light transmission tube characterized by being formed, (2) the light exit side sealing plug is formed of a transparent material, and the infrared reflection or absorption film and / or the ultraviolet reflection or absorption film is formed on at least one end face thereof ( Optical transmission tube of 1), (3)
A transparent core, a tubular clad having a refractive index lower than that of the core and covering the core, and a sealing plug fitted into the openings at both ends of the clad and having at least a light-incident side formed of a transparent material. In an optical transmission tube equipped with
An optical transmission tube characterized by containing an infrared absorber and / or an ultraviolet absorber in the light-transmission-side transparent sealing stopper,
(4) The light transmission tube according to (3), in which the light output side sealing plug is formed of a transparent material, and the sealing plug contains an infrared absorber and / or an ultraviolet absorber.

The present invention will be described in more detail below. As shown in FIG. 1, the optical transmission tube of the present invention is as follows.
A transparent core 1, a tubular clad 2 having a refractive index lower than that of the transparent core 1 and covering the transparent core 1, and sealing plugs 3a and 3b fitted in openings at both ends of the clad are provided. In the present invention, the light-incident-side sealing plug 3a is formed of a transparent material, and when light is emitted from the other sealing plug 3b, the other light-exiting-side sealing plug 3b is also formed of a transparent material. In addition, when light is emitted from the end face of at least one of the entrance side sealing plugs 3a and the exit side sealing plug 3b is also transparent, preferably at least one of the exit side sealing plugs 3b is formed. An infrared reflecting or absorbing film and / or an ultraviolet reflecting or absorbing film 4 is formed on the end face. In FIG. 1, since the outer exposed surfaces of the sealing plugs 3a and 3b are only outer end surfaces, the infrared reflection or absorption film and / or the ultraviolet reflection or absorption film 4 is formed only on these outer end surfaces. But the sealing plug 3
When the outer ends of a and 3b are projected outward, the infrared reflection or absorption film and / or the ultraviolet reflection or absorption film 4 is formed on the entire outer projection surface, that is, the outer end surface and the outer projection outer peripheral surface. Preferably.

Here, the infrared ray film and the ultraviolet ray film can be formed on either or both of the outer end surface A and the inner end surface B of the sealing plug. For example, when both the ultraviolet film and the infrared film cannot be simultaneously formed on the outer end surface, the ultraviolet film can be formed on the outer end surface and the infrared film can be formed on the inner end surface.

Generally, for the purpose of preventing the core from being heated by infrared rays, an infrared ray film may be provided on the outer (incident) end surface of the light-incident-side sealing plug to prevent deterioration of the core by ultraviolet rays. For the purpose, an ultraviolet film may be provided on the outer (incident) end surface of the light-incident-side sealing plug. When the core is not deteriorated by infrared rays or ultraviolet rays and passes through infrared rays or ultraviolet rays, the above infrared ray film is used for the light entrance side sealing plug or the light exit side sealing plug to prevent the temperature rise and deterioration of the irradiated object. Or a film for ultraviolet rays can be formed.

FIG. 2 shows another embodiment of the present invention. In this example, when the light entrance side sealing plug 3a and the light exit side sealing plug 3b are transparent, it is preferable. An infrared absorbing agent and / or an ultraviolet absorbing agent is kneaded and contained in the light exit side sealing plug 3b.

In this case, for example, the light entrance side sealing plug 3a and the light exit side sealing plug 3b are made to contain an infrared absorbing agent or an ultraviolet absorbing agent, and the outside exposed portions of the sealing plugs 3a and 3b reflect or absorb infrared rays. It is also effective to form a film or an ultraviolet reflection or absorption film.

Here, in the optical transmission tube of the present invention, a solid, liquid or fluid transparent material having a higher refractive index than the clad material is used as the core material.

As the solid transparent material, acrylic resin,
Methacrylic resins are preferably used, for example, alkyl acrylates such as methyl acrylate and methyl methacrylate, homopolymers and copolymers of alkyl methacrylates, other acrylates and methacrylates that can obtain transparent polymers copolymerizable with these monomers. The thing copolymerized can be mentioned.

Specific examples of the liquid or fluid transparent material include aqueous solutions of inorganic salts, polyhydric alcohols such as ethylene glycol and glycerin, silicone oils such as polydimethylsiloxane and polyphenylmethylsiloxane, and the like.
Hydrocarbons such as polyethers, polyesters, liquid paraffin, halogenated hydrocarbons such as trifluorochloroethylene oil, phosphoric acid esters such as tris (chloroethyl) phosphate and trioctylphosphate, polymer solutions prepared by diluting the polymer with an appropriate solvent. Is mentioned.

On the other hand, as a material for forming the hollow tubular clad, it is preferable to use a flexible material such as plastic or elastomer, which can be molded into a tube and has a low refractive index. Specific examples thereof include polyethylene, polypropylene, polyamide, polystyrene,
ABS, polymethylmethacrylate, polycarbonate, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyethylene-vinyl acetate copolymer, polyvinyl alcohol, polyethylene-polyvinyl alcohol copolymer, fluororesin, silicone resin, natural rubber, polyisoprene Examples thereof include rubber, polybutadiene rubber, styrene-butadiene copolymer, butyl rubber, halogenated butyl rubber, chloroprene rubber, acrylic rubber, EPDM, acrylonitrile-butadiene copolymer, fluororubber and silicone rubber.

Of these, silicone-based polymers and fluorine-based polymers having a low refractive index are particularly preferable. Specifically, silicone-based polymers such as polydimethylsiloxane polymer, polymethylphenylsiloxane polymer and fluorosilicone polymer, and polytetrafluoroethylene (P
TFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkoxyethylene copolymer (PFE), polychlorotrifluoroethylene (PCTFE), tetrafluoroethylene-ethylene Copolymer (ETFE), polyvinylidene fluoride, polyvinyl fluoride, vinylidene fluoride-trifluorochloroethylene copolymer, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-propylene hexafluoride- Examples thereof include tetrafluoroethylene terpolymer, tetrafluoroethylene propylene rubber, and fluorine-based thermoplastic elastomer. These materials can be used alone or as a mixture of two or more kinds.

As a transparent material for forming a sealing plug that is transparent and acts as a window material for light, it is preferable that the difference in refractive index from the core material is as small as possible in order to reduce reflection at the interface between the core and the sealing plug. . Specific examples of the material of the sealing plug include quartz glass, Pyrex glass, multi-component glass, sapphire, inorganic glass such as crystal, polyethylene, polypropylene, ABS resin, acrylonitrile.
Styrene copolymer resin, styrene-butadiene copolymer,
Acrylonitrile / EPDM / styrene terpolymer,
Styrene / methyl methacrylate copolymer, (meth) acrylic resin, epoxy resin, polymethylpentene, allyl diglycol carbonate resin, spirane resin, amorphous polyolefin, polycarbonate, polyamide, polyarylate, polysulfone, polyallylsulfone, polyethersulfone Examples thereof include organic glass and plastic transparent materials such as phone, polyether imide, polyimide, polyethylene terephthalate, diallyl phthalate, fluororesin, polyester carbonate, and silicone resin. Among these, quartz glass, Pyrex glass, inorganic glass such as multi-component glass is not only transparent, but also excellent in heat resistance, and also chemically stable,
Can provide excellent performance.

When transparency is not required, metal or ceramics can be used.

Although not shown, in sealing the clad end portion with a sealing plug, heat shrinkage treatment, adhesive treatment, hose band fastening, winding with wire strands, fixing with shape memory alloy, sleeve, O -Mechanical fastening, such as fastening via rings or packing, can be carried out as required. Among them, stainless steel, aluminum, copper, copper alloys such as brass, steel, T
It is preferable that a metal sleeve made of i, Ni, or the like is fitted to the outer peripheral portion of the clad so as to cover the clad, and the sealing plug is fixed to the clad by a caulking method of compressively deforming the sleeve.

Examples of the infrared reflective film formed on the sealing plug include tin oxide, tin oxide doped with antimony and fluorine, indium oxide, indium oxide doped with tin, titanium oxide, chromium oxide, and cobalt oxide. Coatings made of metal oxides such as iron oxide, zirconium oxide and aluminum oxide, metal coatings such as silver, gold, platinum, copper, aluminum and chromium, alloy coatings such as nickel-chromium and nickel-chromium-iron, titanium oxide -Silver-titanium oxide, zinc oxide-silver-zinc oxide, tungsten oxide-silver-tungsten oxide, etc., multilayer film of nickel-chromium and silver or copper, or two or more of the above And the like. As the infrared absorbing film, metal, depending on the application or required specifications,
It is selected from a carbide, an oxide or a composite film thereof, and specifically, one of titanium, chromium, zirconium, tantalum, hafnium, titanium nitride, chromium nitride, zirconium nitride, tantalum nitride, and hafnium nitride is the main component. The above film is preferable because it has good heat ray absorption performance. These may be formed directly on the surface of the window material, or may be formed on a transparent film such as polyethylene terephthalate.

Examples of the infrared absorbing agent include the same materials as those used for the absorbing film, and also transition metal ions (N
Examples thereof include glass doped with (i, Fe, Pt, etc.), glass or polymer having —OH, and polymer having C—H bond.

On the other hand, examples of the ultraviolet absorbing film include commercially available ultraviolet cut filters, metal oxide thin films of titanium oxide, zinc oxide, zirconium oxide, cerium oxide and the like.

Examples of the ultraviolet absorber include benzotriazole-based, sacylate-based, benzophenone-based, cyanoacrylate-based, and hindered amine-based dyes, and glass having poor ultraviolet and infrared transmission can also be used. For example, multi-component glass such as Pyrex glass, white plate glass and BK-7 is suitable. Alternatively, quartz or silica glass containing transition metal ions such as Ni, Fe and Pt may be used.

The amount of the infrared absorber or the ultraviolet absorber incorporated into the sealing stopper is an effective amount and is not limited. For example, depending on the length of the sealing stopper, the length is about 30 mm. If so, 0.07 parts by weight or less is sufficient for 100 parts by weight of the material forming the sealing plug in the sealing plug.

Here, the infrared absorber and / or the infrared absorber shown in FIG.
Alternatively, in a mode in which the ultraviolet absorber is contained in the sealing plugs 3a, 3b, the antireflection film 5 for visible light can be further formed on the outer exposed surface thereof, thereby improving the light incident or emission efficiency. You can

The infrared film and the ultraviolet film are required to be transparent so as not to interfere with visible light and allow it to pass therethrough. For this reason, a metal film or the like should be thin in the angstrom order. The film thickness is selected so that light can pass through. Further, the infrared reflection or absorption agent and the ultraviolet reflection or absorption agent are those which achieve desired infrared rays, visible rays or ultraviolet rays by changing the thickness of the film in accordance with the wavelength to be cut. The thickness of the film for ultraviolet rays and the film for ultraviolet rays is thus selected according to the transparency and the wavelength to be cut.

In the present invention, the cladding can be coated with an appropriate coating material for the purpose of protecting the optical transmission tube. The coating material can be selected from plastic, elastomer, metal, glass, and inorganic material.

Specifically, polyamide, epoxy resin,
Polymers such as polyvinyl chloride, polycarbonate, polystyrene, fluororesin, butyl rubber, halogenated butyl rubber, polyethylene, polypropylene, polyurethane, hydrochloric acid rubber, natural rubber, polyisoprene rubber, polybutadiene rubber, chloroprene rubber, acrylic rubber, EPDM, fluororubber The material can be coated, extruded, wrapped with a tape-shaped material, heat-shrinked or the like to cover the clad.

Further, metal materials such as SUS, aluminum, copper, iron, etc., or the above-mentioned polymer materials are pipe-shaped, bellows-shaped,
You may insert the clad which covered the core in what was shape | molded in the shape of a spiral wire. Furthermore, a metal material may be coated on the outer periphery of the clad by plating, vapor deposition, sputtering or the like to cover the metal film.

These coating materials can be used alone or as a composite with other materials.

The above-mentioned coating material can be provided not only for the purpose of protecting the light transmission tube but also for the purpose of blocking light or causing only the required portion to emit light. For example, when a hole is formed in a required portion of the above covering material or the portion is made transparent, light leaks out from the portion to form a large number of spot-shaped or line-shaped light emitters. In this case, the antireflection film can be formed on the outer surface of the light emitting portion, if necessary.

[0032]

The present invention will be described below in more detail with reference to Examples, but the present invention is not limited to the following Examples.

Example 1 Tetrafluoroethylene-hexafluoropropylene copolymer (FEP, n = 1.34, inner diameter 12
mm, an outer diameter of 13 mm), methylphenyl silicone oil (n = 1.5) is injected as a core into the center of the clad,
Quartz glass (diameter 13 mm x length 30 mm) was enclosed as a window material. Further, the bases were fastened and attached to the outer peripheral portions of both ends of the clad, and the window material was firmly fixed to the clad.
At this time, an ITO film, which is a composite oxide of tin oxide and indium oxide, was formed on the outer end surface of the quartz glass to give a heat ray reflecting function. A 150 W halogen lamp was entered, but the temperature rise around the base was slight.

Example 2 An optical transmission tube was prepared in the same manner as in Example 1 except that a methacrylic resin was used as the window material. This window material had 100 parts by weight of the resin and a benzotriazole-based ultraviolet absorber 0 After mixing 0.001 parts by weight with methacrylic resin, it was prepared by injection molding (diameter 1
3 mm x length 30 mm). As a result, an ultraviolet ray absorbing function was imparted, and a 150 W meta-hala lamp was incident for 500 hours, but no deterioration of the core was observed.

Example 3 An optical transmission tube similar to that of Example 1 was produced, but a thin film of titanium oxide was formed on the surface of the quartz glass window material at this time. Thereby, at the same time that the infrared reflecting function is imparted, the thin film also has an ultraviolet absorbing function, so that only visible light can be guided.

[Embodiment 4] Pyrex rod (diameter 13 mm x length 30 mm) having a poor UV transparency as a window material.
An optical transmission tube was produced in the same manner as in Example 1 except that was used. A 150 W meta-hara lamp was incident for 500 hours, but no deterioration of the core was observed.

[0037]

INDUSTRIAL APPLICABILITY The optical transmission tube of the present invention is capable of preventing infrared rays and ultraviolet rays from entering the core as much as possible, preventing deterioration of the core, and having stable optical transmission characteristics for a long period of time. Is. It is also possible to prevent the temperature rise and deterioration of the object to be irradiated.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a light transmission tube of the present invention.

FIG. 2 is a cross-sectional view showing another example of the optical transmission tube of the present invention.

[Explanation of symbols]

1 Core 2 Clad 3a, 3b Sealing Plug 4 Infrared Reflection or Absorption Film and / or Ultraviolet Reflection or Absorption Film 5 Antireflection Film

Claims (4)

[Claims] 1. A transparent core (1), a tubular clad (2) having a refractive index lower than that of the core (1) and covering the core (1), and openings at both ends of the clad (2). And a sealing plug (3a, 3b) each of which is fitted on the light-receiving side and is formed of a transparent material at least on the light-incident side, in at least one end surface of the light-transmissive-side transparent sealing plug (3a). An optical transmission tube comprising an infrared reflection or absorption film and / or an ultraviolet reflection or absorption film (4). 2. The light output side sealing plug (3b) is formed of a transparent material, and an infrared reflecting or absorbing film and / or an ultraviolet reflecting or absorbing film (4) is formed on at least one end face thereof. Light transmission tube. 3. A transparent core (1), a tubular clad (2) having a refractive index lower than that of the core (1) and covering the core (1), and openings at both ends of the clad (2). And a sealing plug (3a, 3b) each of which is fitted on the light-receiving side and is made of a transparent material at least on the light-receiving side. And / or an optical transmission tube containing an ultraviolet absorber. 4. The optical transmission according to claim 3, wherein the light-outlet-side sealing plug (3b) is formed of a transparent material, and the sealing plug (3b) contains an infrared absorber and / or an ultraviolet absorber. tube.