JP2002207134A - Hollow waveguide end face sealing cap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hollow waveguide sealing cap in a wide infrared wavelength band which is manufactured at a low cost, is excellent in durability, is nonpoisonuous because of being used for medical treatment and is not also affected by an atmosphere of disinfection/sterilization. SOLUTION: The hollow waveguide sealing cap is used by being attached to the end face of a hollow waveguide, one end of the cap is sealed and the cap is composed of a short crystal column of sodium chloride or potassium chloride having a columnar hole.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an end sealing cap for a hollow waveguide.

[0002]

2. Description of the Related Art A hollow waveguide or a hollow fiber has a large material loss and cannot be transmitted by a solid type fiber, such as a carbon dioxide gas laser and an erbium yag.
It is being developed as a transmission line for ultraviolet lasers such as excimer lasers. In addition, since this hollow fiber uses air or gas as the core, it has a small reflection loss at the end face and a low possibility of destruction of the end face. Therefore, it is suitable for transmission of large optical power. Even in the wavelength range where fiber can be used, applications in the medical fields such as dentistry, dermatology, otolaryngology, and surgery are open.

When applying a hollow fiber to laser treatment,
When blood or body fluid emitted from a target irradiated with laser, human tissue removed by laser irradiation, or carbon generated by laser irradiation enters the inside of a hollow core, the properties of the hollow fiber deteriorate or break. And so on. Furthermore, in order to use a hollow fiber inserted into the body, it is essential that the end face of the hollow fiber be sealed.

Therefore, conventionally, a method has been adopted in which a window material such as sapphire, quartz, or calcium fluoride is bonded to the end face of the hollow fiber to seal the end face. In addition, as another method of sealing the end face, a glass cap with an end face has recently been proposed for erbium yag laser.

[Problems to be solved by the invention]

However, since materials such as sapphire, quartz, and calcium fluoride and their processing are expensive, the cost of sealing the hollow fiber is high. When using hollow fibers for medical applications,
In some cases, the adhesive used to fix the sealing material was eluted, and heat was generated in that area, and the sealing function was not fulfilled. Therefore, in this case, it was difficult to adapt to a treatment method in which a hollow fiber was inserted into the body.

On the other hand, the glass cap for sealing the end face is effective only in the wavelength region where the glass is transparent. In the case of the laser in the infrared wavelength band, the fiber for the erbium yag laser is the limit, and the hollow portion for the laser having a longer wavelength is used. There was an essentially insurmountable problem that it could not be applied to fiber.

Therefore, an object of the present invention is to solve the above-mentioned problem so that it is possible even in a wide infrared wavelength band. The cap is a sealing cap for hollow waveguide using sodium chloride or potassium chloride crystal, or a material in which the crystal is coated with organic resin on the surface. The sealing cap can be manufactured at low cost and is non-toxic and durable, while at the same time it is disposable and does not suffer from the atmosphere of resin-coated cap disinfection sterilization.

[0008]

In order to achieve the above object, the present invention uses, as a material, a crystal column of sodium chloride or potassium chloride which is transparent in a wide wavelength band from visible to infrared. The crystal column has a cylindrical hole, into which a hollow fiber is inserted, and one end of the hollow fiber is sealed by this.

Here, by appropriately controlling the shape of the end face of the sodium chloride or potassium chloride crystal column acting as a seal, the end face can be made a lens condensing element, a diverging element, or the like.
It can function as a uniform irradiation element.

Further, by using a dipping method or the like, an organic resin such as a cyclic olefin polymer, a fluorine resin, or a polyimide can be formed on the crystal pillar to prevent dissolution of the crystal and protect the crystal.

Such a hollow fiber sealing cap of the present invention can be manufactured at an extremely low cost, has excellent durability, is non-toxic, and is not affected by an atmosphere of disinfection and sterilization. It is possible to realize a sealing cap for hollow fibers in a wide infrared wavelength band including carbon dioxide laser light.

[0012]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a cross-sectional view showing one embodiment of a cap for sealing a hollow waveguide of the present invention. A sodium chloride or potassium chloride cap 2 is attached to the end face of the hollow waveguide 1 and a core 3 of the hollow waveguide is provided.
The structure is such that foreign matter does not invade from outside.

The fixing of the cap is performed by bonding the hollow fiber to the vicinity of the opposite end of the cap which has no influence on the transmitted light. By properly selecting the adhesive, it is possible to remove the cap without affecting the hollow fiber, so that if the cap 2 is damaged or contaminated, it can be easily replaced. It is also possible to easily sterilize only the cap.

Since the inner diameter of the cap 2 is almost the same as or slightly larger than the outer diameter of the hollow waveguide 1, the hollow waveguide 1
By simply inserting the cap 2 into the cap 2, the cap 2 can be fixed without using an adhesive. When gas is sealed in the core of the hollow waveguide 1 or when the inside of the core is evacuated, the cap 2 is bonded with an adhesive or grease in order to enhance the adhesion between the cap 2 and the hollow waveguide 1. 2 may be fixed.

As an example of a method for manufacturing the sodium or potassium chloride cap 2 for sealing, a hole having a diameter approximately equal to the outer diameter of the hollow fiber is drilled into the same crystal having an appropriate cross-sectional area and length. It can be manufactured by forming. Alternatively, for mass production, a columnar hole is drilled at equal intervals in the same crystal having an appropriate length and a relatively large cross section, and then divided by cleavage.
There is also a method of forming many caps.

FIG. 2A is a cross-sectional view when the sealing surface of the cap 2 has a plano-convex lens shape, and FIG. 2B is a cross-sectional view when the sealing surface has a plano-concave lens shape. These shapes can be formed by making the shape of the drill appropriate and polishing and dissolving the outer surface with water or alcohol.

FIGS. 2C and 2D are cross-sectional views when the sealing surface of the cap 2 has a meniscus lens shape. In this case as well, the shape can be controlled by the shape, polishing and melting of the drill, thereby making it possible to converge and diverge the beam emitted from the end face.

The cross-sectional area of the sealing end face is usually limited to a square or a rectangle because sodium or potassium chloride crystals are hexagonal. By making the end face rectangular, the light distribution from the hollow fiber spreads within the sealed end face, and various emission distributions for the intended purpose can be obtained.

Since sodium chloride or potassium chloride has the property of being soluble in water, in order to overcome this, the sealing element obtained above is coated with an organic resin such as a cyclic olefin polymer, a fluorine resin or a polyimide.
Cyclic olefin polymer, fluororesin,
Alternatively, if a liquid film is formed on the surface of the same crystal by dipping or the like in a polyimide precursor solution and heat treatment is performed,
These films are formed.

In summary, according to the present invention, the following excellent effects are exhibited.

It is possible to seal a hollow fiber corresponding to a wide infrared wavelength. Excellent mass productivity and low-cost production. Has excellent durability. There is no interaction between the laser beam and the adhesive, and there is no effect on the human body due to the elution of the adhesive. It is possible to form sealing materials of various shapes and to form sealing materials with various optical functions.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2A is a cross-sectional view showing an example of an embodiment when a sealing surface of a cap has a plano-convex lens shape. (B) It is sectional drawing which shows an example of embodiment when the sealing surface of a cap is made into the shape of a plano-concave lens. (C) It is sectional drawing which shows an example of embodiment when the sealing surface of a cap is made into the outer surface convex meniscus lens shape. (D) is a cross-sectional view showing an example of the embodiment in the case where the sealing surface of the cap has an outer concave meniscus lens shape.

[Explanation of symbols]

 Reference Signs List 1 hollow waveguide 2 sodium chloride or potassium chloride cap 3 hollow waveguide core region

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Yuji Matsuura Aoba-maki Aoba, Aoba-ku, Aoba-ku, Sendai City, Miyagi Prefecture (72) Inside of Faculty of Engineering, Tohoku University No address) Tohoku University Faculty of Engineering F-term (reference) 2H050 AC64 AC86 AC90

Claims (3)

[Claims] 1. A cap for sealing a hollow waveguide, wherein an end face of a hollow waveguide is inserted into a cylindrical hole provided in a crystal column of sodium chloride or potassium chloride. 2. The hollow waveguide sealing device according to claim 1, wherein said crystal pillar functions as a condensing, diverging or uniform irradiation element by appropriately controlling the end face shape of said crystal column. cap. 3. The hollow waveguide sealing cap according to claim 1, wherein an outer surface of said crystal column is coated with an organic resin.