JPH02277006A - Production of optical fiber with lens - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing a lens-equipped optical fiber used in an optical semiconductor element module using an optical fiber.

[Conventional technology]

Generally, as a method for optically coupling an optical semiconductor element and an optical fiber in an optical semiconductor element module used for optical communication using an optical fiber.

There is a method of using individual lenses such as a ball lens or a gradient index lens, and a method of using an optical fiber with a lens in which the lens is integrated with the optical fiber.

Figure 5 is a cross-sectional view of a conventional lens-equipped optical fiber shown on page 261 of "Optical Communication Device Engineering" by Hiroo Yonezu (Publisher: Kogaku Tosho Co., Ltd.). In Figure 9, (201) is a laser diode.

(202) is a tapered spherical optical fiber in which the tip of the optical fiber is tapered and the end is processed into a spherical surface to form a lens.

The radius of curvature of the spherical surface formed at the tip of the tapered spherical optical fiber (202) is about 10 μm. The reason why the tip of the optical fiber is tapered is to form a spherical surface with a radius of curvature of about 10 μm on an optical fiber with an outer diameter of about 125 μm.

Next, the operation will be explained.

The emitted light from the laser diode (201) is focused on the spherical surface at the tip of the tapered spherical optical fiber (202) and optically coupled to the optical fiber.

Next, the manufacturing method will be explained.

First, the tip of the optical fiber is processed into a tapered shape. Processing methods include mechanical processing methods such as grinding, and chemical processing methods such as changing the amount of etching in the length direction of the optical fiber by gradually pulling up the optical fiber immersed in fluoric acid.

Next, the tapered tip is polished to form a spherical surface with a radius of curvature of about 10 μm.

By the way, the above processing has a thin outer diameter of about 125 μm,
Furthermore, the present invention was applied to optical fibers made of a material that is easily damaged, such as 9-quartz glass. For this reason, careful attention and skill are required during processing. Furthermore, the spherical processing of the tip is 9
Since the radius of curvature is very small, about 10 μm, manufacturing equipment with a 9% special size is required.

[Problem to be solved by the invention]

Conventional lens-equipped optical fibers are constructed as described above, so processing requires great care and skill, and special manufacturing equipment is required to process the tip into a spherical shape, making mass production difficult. There were issues such as low yield and high price.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a method for manufacturing a lens-equipped optical fiber that is highly mass-producible and can be manufactured without special manufacturing equipment.

[Failure to solve the problem]

The optical fiber with a lens according to the present invention has a substantially hemispherical organic substance or glass lens larger than the center hole fixed on the center hole of an optical fiber holder, and the optical fiber is fixed to the optical fiber holder. .

Further, in the method for manufacturing a lens-equipped optical fiber according to the present invention, a liquid transparent organic substance is applied to the end face of an optical fiber and an optical fiber holder to which the optical fiber is fixed in a substantially hemispherical shape, and then cured.

Further, in another method of manufacturing an optical fiber with a lens according to the present invention, a substantially spherical glass is placed in the center hole of an optical fiber holder, the glass is softened by heating and fixed to the optical fiber holder, and then the optical fiber is is fixed to an optical fiber holder.

[Effect]

In the optical fiber with lens according to the present invention, the lens is fixed to the end face of the optical fiber holder.

Compared to a lens formed at the tip of an optical fiber.

Easy to handle.

Furthermore, the method for manufacturing a lensed optical fiber according to the present invention is one in which a lens is fixed to the end face of an optical fiber holder by a simple method, and can be manufactured without special manufacturing equipment, and can be manufactured by hardening an organic substance or glass. Since many things can be softened at the same time, mass production is high and the price is low. In the past, the surface of lenses used the surface tension of liquid organic substances or softened glass, resulting in a smooth surface with no bumps or scratches.

〔Example〕

An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a cross-sectional view of the optical fiber holder with lens! 0
．． (6) is an optical fiber, (7) is an optical fiber jacket made of nylon resin or the like, α is an optical fiber holder, and (1) is a lens. Optical fiber (6) and optical fiber jacket (7)
is fixed to the center hole of the optical fiber holder (13) with adhesive.Lens 4 is fixed to the center hole of the optical fiber holder (13), and the size of the lens (to) is determined by the size of the optical fiber holder (13). It is larger than the center hole of No. 13.

Further, the optical fiber (6) and the lens (to) are in close contact with each other.

FIG. 2 is a sectional view of an embodiment in which an optical semiconductor element and an optical fiber are optically coupled using the lens-equipped optical fiber holder of the present invention.

(101) is an optical semiconductor light emitting device, and (102) is a ball lens.

The light emitted from the optical semiconductor light emitting device (101) is transmitted through the ball lens (10
2) The focused light enters the lens-equipped optical fiber holder, is focused by the lens, and enters the optical fiber (6).

A nine-ball lens (1
02) and it is necessary to adjust the position of the lensed optical fiber, but the lens system is divided into a 9-ball lens (102) and a lens (2), and the focal length of the lens is different from that shown in the conventional example. The adjustment accuracy of the position is the same or relaxed compared to the conventional example, due to the fact that it is larger than the conventional example.

In addition, if the outer diameter of the optical fiber holder α3 is 2.5 μm, it is 20 times larger than the outer diameter of the optical fiber, which is about 125 μm, and metals and ceramics can be used for the material, and the easily damaged optical fiber is exposed. Since there is no such thing, it is easy to handle.

Furthermore, since the lens is directly fixed to the optical fiber holder, the optical coupling between the optical semiconductor element and the optical fiber will not change due to movement of the lens due to aging or the like.

Next, an embodiment of the method for manufacturing a lensed optical fiber according to the present invention will be described with reference to the drawings.

Fig. 3 is a cross-sectional view showing the manufacturing process, and in Fig. 99, 2
υ is a liquid organic substance such as transparent epoxy resin or silicone resin, and liquid organic substance clD is 60℃ to 150℃.
Cures at a temperature of °C. OD is a syringe needle.

The optical fiber (6) and the optical fiber jacket (7) are fixed to the optical fiber holder αJ with adhesive. The end face of the optical fiber (6) is polished into a υ plane after the optical fiber holder a3 and the optical fiber (6) are adhesively fixed.

An appropriate amount of liquid organic substance Qυ is applied to the end surfaces of the optical fiber (6) and the optical fiber holder Q3 using a syringe needle Gυ. At this time, the coating positions are the center of the optical fiber (6) and the liquid organic substance (material) that has been coated into a hemispherical shape.
The center of the image should almost match the center of the image. It was. Liquid organic matter? 2υ should be raised into a hemispherical shape due to surface tension.

Thereafter, the liquid organic substance is cured by heating to produce a lens-equipped optical fiber.

Liquid organic substance c! The manufacturing equipment that performs tasks such as applying the appropriate amount of chlorine and determining the position to apply can be easily automated by combining simple jigs and manufacturing equipment that is usually commercially available. can be worked on. 9 Working time is also short. moreover.

Since liquid organic substances can be cured simply by heating, a large number of substances can be treated at the same time. Therefore, mass production is high and the price is low.

Next, an embodiment of another method for manufacturing a lensed optical fiber according to the present invention will be described with reference to the drawings.

Figure 4 is a cross-sectional view showing the manufacturing process.
is a transparent spherical glass whose coefficient of thermal expansion approximately matches that of the optical fiber holder.

A spherical glass @ is placed over the center hole of the optical fiber holder 0, heated to 400 to 700°C in an electric furnace, etc. to soften the spherical glass, and then placed into an almost hemispherical shape on the end face of the optical fiber holder α1. I will make it happen. At this time.

The diameter of the center hole of the optical fiber holder α is as small as 127 μm, which is slightly larger than the outer diameter of the optical fiber, and the viscosity of the softened glass is appropriate. Almost never enters. Next, the outer jacket of the tip part is removed, and the optical fiber whose end face is neatly broken with a fiber cutter or the like is inserted through the other hole of the optical fiber holder αJ and fixed using an adhesive.

Glass can be softened by simply heating it, and by adjusting the temperature it can be processed with good reproducibility. Also.

Since the outer diameter of the optical fiber holder 0 is about 2.511E, which is small for a processed part made of metal or the like, many parts can be processed with lenses at the same time. Therefore, mass production is high and the price is low. Moreover, it is sufficient to produce a large quantity of lenses (1) fixed to optical fiber holders α, and to insert and fix optical fibers as necessary.

It is easy to handle, which improves work efficiency.

In the above embodiment, the optical fiber (6) and the optical fiber holder 0 are fixed with adhesive, but they may be fixed using solder.

Further, in the above embodiments, when organic substances are used as the material of the lens, epoxy resin and silicone resin are shown, but acrylic resin or the like may be used.

Further, in the above embodiment, when the material of the lens (1) is an organic substance, the organic substance is cured by heating, but it may also be cured by ultraviolet irradiation, or it may be cured at room temperature. But it's okay.

〔Effect of the invention〕

As described above, according to the present invention, since the lens is configured to be fixed to the end face of the optical fiber holder, it is easy to handle, does not require special manufacturing equipment, and has the advantage of being highly mass-producible and inexpensive. There is.

Alternatively, a silica lens can be formed by applying a liquid organic substance to the end face of an optical fiber holder and then hardening it, or by placing it on the end face of a spherical glass optical fiber holder and then heating it to soften the glass. Therefore, mass production is high and 2%
No special manufacturing equipment required.

It has the effect of being able to be manufactured at low cost.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing a lens-equipped optical fiber according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing an optical semiconductor light-emitting device and an optical fiber optically coupled using the lens-equipped optical fiber of FIG. 1. A sectional view of an embodiment; FIG. 3 is a sectional view showing a method of manufacturing a lens-equipped optical fiber according to another embodiment of the present invention;
FIG. 4 is a sectional view showing a method of manufacturing a lensed optical fiber according to another embodiment of the present invention, and FIG. 5 is a sectional view of a conventional lensed optical fiber. (6) is an optical fiber, a3 is an optical fiber holder, ■ is a lens, Qυ is a liquid organic substance, and (2) is a spherical glass. In addition, in FIG. 9, the same reference numerals indicate the same or corresponding parts.

Claims (3)

[Claims] (1) In a method for manufacturing a lensed optical fiber in which a lens is formed at the tip of the optical fiber, the optical fiber is attached to the center hole of an optical fiber holder having a center hole larger than the outer diameter of the optical fiber using adhesive or solder. A method for producing an optical fiber with a lens, comprising: fixing the optical fiber, applying a liquid transparent organic substance to the end face of the optical fiber holder and the optical fiber in a substantially hemispherical shape, and then curing the organic substance. (2) In a method for manufacturing a lensed optical fiber in which a lens is formed at the tip of an optical fiber, a diameter larger than the outer diameter of the optical fiber is formed on the center hole of an optical fiber holder having a center hole larger than the outer diameter of the optical fiber. The optical fiber is fixed to the center hole of the optical fiber holder after the glass is softened by heating to become approximately spherical and fixed to the optical fiber holder. Method for manufacturing optical fiber with lens. (3) In a lens-equipped optical fiber in which a lens is formed at the tip of the optical fiber, an optical fiber, an optical fiber holder having a center hole larger than the outer diameter of the optical fiber and a center hole larger than the outer diameter of the optical fiber; and a lens made of an organic material or glass having an outer diameter larger than the center hole, the lens being fixed to the center hole of the optical fiber holder, and the optical fiber being attached to the optical fiber holder with adhesive or solder. A lens-equipped optical fiber manufactured by the method for manufacturing a lens-equipped optical fiber according to claim (1) or (2), characterized in that the lens-equipped optical fiber is fixed.