JP2003222774A - Optical communication component and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an optical communication component capable of distributing force applied to an optical element and preventing a break of the optical element. <P>SOLUTION: In the optical communication component, the optical element partially having flat faces on a light incident end face and a light exit end face is fixed to a metal holder, the holder is provided with a large inside diameter having an inside diameter approximately equal to an outer diameter of the optical element and a small inside diameter smaller than the large inside diameter, a step is provided between the large and small inside diameters, a thin part internally bent at an angle of 90° or more is formed at an opening end of the large inside diameter, and the flat faces on the light incident end face and the light exit end face of the optical element accommodated in the large inside diameter are pinched and fixed by surface contact of the step and the bent thin part. <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 an optical communication component which is a member constituting an optical system used for optical communication and the like, and a manufacturing method thereof.

[0002]

2. Description of the Related Art In optical communication equipment, various inspection devices, various optical sensors, laser devices, etc., a large number of optical communication components such as optical isolators, lenses, etc., in which optical elements are fixed to holders are used.

Generally, these optical communication components are provided with an optical element 1, a holder 2, and further an optical element 1 and a holder 2 as shown in FIG.
It is composed of a bonding material 3 for fixing. An adhesive, solder, low melting point glass, or the like is used as the bonding material.

A method of fixing the holder and the optical element without using a bonding material has also been devised. For example, as shown in FIG. 7, the holder 4 is provided with a thin-walled cylindrical portion 6 having an inner diameter slightly larger than the outer diameter of the ball lens 5, and inside the thin-walled cylindrical portion 6, the outer diameter of the ball lens 5 is smaller than that of the light beam. This is a method in which a step portion 7 having a hole diameter that does not block the optical path is provided, and the outer circumference of the thin-walled cylindrical portion 6 is caulked and fixed while the spherical lens 5 is in contact with the step portion 7 (JP-A-2-
32307). Similarly, a method of crimping a metal holder to fix a cylindrical lens has also been proposed (see Japanese Patent Laid-Open No. 2-262607).

[0005]

However, the method using the bonding material 3 shown in FIG. 6 has the following problems. First, when an adhesive is used as the bonding material 3, there is a problem in that outgas generated from the adhesive adversely affects other parts. Further, there is a problem that the adhesive takes a long time to cure and the workability is deteriorated. Further, since the adhesive generally deteriorates due to absorption of water under high temperature and high humidity conditions, there is a problem in reliability of parts.

Further, when solder or low melting point glass is used for the bonding material 3, when the optical element 1 and the holder 2 are fixed, if there is a difference in the thermal expansion coefficient between the optical element 1 and the holder 2, the bonding material 3
Also, the optical element 1 is cracked or cracked. Therefore, it is necessary to use a material having a thermal expansion coefficient close to that of glass such as Kovar or Ni—Fe alloy for the holder 2. However, Kovar and Ni-Fe alloys have problems in that they are difficult to cut and that the material itself is expensive, so that the cost cannot be reduced.

In the method of fixing the ball lens 5 and the holder 4 without using the bonding material shown in FIG. 7, since the outer peripheral portion of the ball lens 5 is caulked and fixed, the thin wall of the holder is attached to the spherical surface of the ball lens 5. It is difficult to fix the cylindrical portion 6 so as to be in close contact with it evenly, and a non-uniform force is applied to the ball lens 5, and the ball lens 5 is cracked or cracked over time. was there.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an optical element having at least a part of its end face through which light enters and exits is a flat surface is fixed to a holder made of metal. In the optical communication component, the holder includes a large inner diameter portion having an inner diameter substantially the same as the outer diameter of the optical element, and a small inner diameter portion smaller than the large inner diameter portion, and a step portion between the two. 9 on the open end side of the large inner diameter of the holder
The flat part on the entrance and exit sides of the optical element housed in the large inner diameter part, which has a thin part bent inward by 0 ° or more, is fixed by being sandwiched by the step part of the holder and the thin part. It is characterized by

Further, a cushioning material is provided between the optical element and the holder.

Furthermore, the thin portion of the holder is
It is characterized by applying a load of up to 1000 g and caulking.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a lens holder according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 (a) is a sectional view, and FIG. 1 (b) is a sectional view of the holder 2 before assembly. The holder 2 is
A large inner diameter portion 8 having an inner diameter substantially the same as the outer diameter of the optical element 1, and a small inner diameter portion 9 having a hole diameter smaller than the inner diameter of the large inner diameter portion 8 and not blocking the optical path of the light beam. 8
A step 10 is provided at the boundary between the small inner diameter portion 9 and. When fixing the optical element 1, the optical element 1 is housed in the large inner diameter portion 8 so as to be brought into contact with the step 10, and the thin portion 11 on the open end side of the large inner diameter portion 9 is bent inward by 90 ° or more. Fix by caulking.

In the state before the holder 2 is assembled, as shown in FIG. 1B, a step 10 is formed at the boundary between the large inner diameter portion 8 and the small inner diameter portion 9.
Is formed, and a thin-walled portion 11 is formed continuously on the open end side of the large inner diameter portion 8 by thinning the outer diameter by processing to a taper shape of about 45 degrees.

In the optical element 1, at least a part of the flat surface of the end surface on the incident side and the surface on the output side are sandwiched by the step 10 and the thin portion 11 bent by 90 ° or more by caulking and fixed by surface contact. It is held by the holder 2. By forming the thin portion 11 on the holder 2,
The metal can be caulked with a small force, and the force applied to the optical element 1 can be reduced. Further, by making the metal thin, the metal is easily deformed, and since the optical element 1 has a flat surface portion, it is possible to closely adhere along the flat surface portion, so that the optical element 1 is firmly fixed. Become.

Further, by bringing the optical element 1 and the holder 2 into close contact not by points but by surface contact, the force applied to the optical element 1 can be dispersed and the destruction of the optical element 1 can be prevented. The caulking portion does not necessarily have to cover the entire circumference of the thin portion 11,
For example, as shown in FIG. 1 (c), partial caulking portions 12 may be provided in several places and fixed by caulking. By fixing the part by caulking, it is possible to reduce the load applied to the optical element 1 as compared with the case where the optical element 1 is fixed over the entire circumference, and the shape of the optical element 1 is complicated, so that the plane portion has only the entrance and exit side end faces. Even if there is only one part, caulking can be fixed.

Also, when caulking and fixing, the thin portion 11
As shown in FIG. 2, the tapered shape 1 is formed on the inner diameter side of the thin portion 11 so that the corners of the optical element 1 and the optical element 1 do not come into contact with each other and the optical element 1 is destroyed.
By providing 3, when the thin portion 11 is crimped and bent,
The thin portion 11 and the corners of the optical element 1 do not come into contact with each other, and the optical element 1 can be prevented from being broken.

Further, as shown in FIG. 3, a shock absorbing material 14 made of a soft material that is plastically deformed is inserted between the outer periphery of the optical element 1 and the large inner diameter portion 8 of the holder 2 so as to reduce the impact when caulking and fixing. It becomes possible to do. Suitable materials for the cushioning material 14 are, for example, tin, gold, silver, copper, nickel, chromium, aluminum, silicon rubber and the like.

If the load applied when the holder 2 is caulked and fixed is too large, the optical element 1 will be destroyed, and if it is too small, sufficient fixing strength of the optical element 1 cannot be obtained. Need to be added. In the present invention, loads in the range of 50 g to 1000 g are suitable. If the load is less than 50 g, the optical element 1 will not be cracked or broken, but if the optical element 1 wobbles and a load of 1000 g or more is applied, the optical element 1 will be broken and cannot be fixed.

A thinner portion 11 can be bent with a smaller force as the thickness thereof is thinner, but at the same time, the fixing strength of the optical element 1 becomes weaker, so that it is preferable that the thickness is about 0.05 to 0.1 mm. Further, the longer the bent portion of the thin portion 11 is, the stronger the fixing strength of the optical element 1 is.
At the same time, the force applied to the optical element 1 increases, so 0.0
A length of about 5 to 0.1 mm is desirable. Similarly, since the width of the step 10 between the large inner diameter portion 8 and the small inner diameter portion 9 of the holder 2 serves as an abutment when fixing the optical element 1, the wider the width, the more stably the optical element 1 is fixed. However, since the force applied to the optical element becomes large at the same time, a width of about 0.05 to 0.1 mm is desirable.

Next, a method of fixing the optical element 1 having the above-mentioned structure will be described with reference to the drawings. In the present invention, FIG.
The caulking machine 15 as shown in FIG. The mechanism of the caulking machine 15 is provided with a mechanism for swinging and rotating the holder 2 around the axis as shown in FIG. 4, and the processing jig 16 is attached to the tip. FIG. 5 shows the shape of the processing jig 16. The inner end of the jig has a taper shape in which the inner wall spreads about 45 degrees toward the open end. While the tapered portion is in contact with the thin wall portion 11 of the holder 2, the thin wall portion 11 is pushed and bent by 90 ° or more by pivoting the holder 2 around the shaft while pressurizing with a load of 50 g to 1000 g. , Are fixed by caulking by planar contact along the flat surface of the optical element 1.

Next, the material will be described.

First, as the material of the holder 2, it is desirable to use stainless steel having a small expansion coefficient, but other metals or non-metals can be used. For example, metal includes kovar, iron / nickel alloy, iron / nickel / chromium alloy, iron / chrome alloy, and the like, and nonmetal includes copper, aluminum, magnesium, and the like.

With respect to the optical element 1, other than the lenses described above, optical isolator constituent members such as a polarizer, an analyzer and a Faraday rotator, an optical rotator, a reflecting mirror, a semitransparent reflecting mirror, a beam splitter and a filter. , Prism, diffraction grating, calcite, rutile, LN crystal, etc.
It is possible to apply all the members constituting the optical system such as the 2λ wavelength plate, the 1 / 4λ wavelength plate and the mirror. However, it is necessary that at least a part of the end surface side of the member on which light enters or exits is a flat surface.

[0024]

EXAMPLES Here, an experiment was conducted by the following method.

With respect to the lens holder shown in FIG. 1 of the present invention, a confirmation experiment was conducted on the wobbling state of the optical element 1 when the load during caulking was changed, and the cracks and cracks of the optical element 1. As the optical element 1, a 0.5 mm thick polarizer in which metal particles are dispersed in glass has a diameter of 1.4.
mm processed into a cylindrical shape, the holder 2 is made of stainless SF20T, and has an outer diameter of 3 mm and a thickness of 0.5.
mm, the large inner diameter portion 8 had a diameter of 1.41 mm, the small inner diameter portion 9 had a diameter of 1.25 mm, and the thin portion 11 had a taper angle of 45 ° and a length of 0.1 mm. 2 by changing the load condition
Table 1 shows the results of the trial manufacture of 0 pieces.

[0026]

[Table 1]

From the above results, it was found that the optical element 1 wobbles although the optical element 1 was not cracked or broken when the load was less than 50 g. This indicates that the optical element 1 is not firmly fixed because the load is not sufficiently large and the caulking is not sufficiently performed. Also,
It was found that when a load exceeding 1000 g was applied, the optical element 1 was destroyed and could not be fixed. This means that the load is too large and the optical element 1 cannot bear the load and is destroyed. From this, load 5
If you apply a load in the range of 0g to 1000g,
It was found that the caulking and fixing were performed safely and securely.

[0028]

As described above, according to the present invention, in the optical communication component in which the optical element having at least a part of the light incident side end surface and the light emitting side end surface being a flat surface is fixed to the holder made of metal, the holder is provided. Has a large inner diameter portion having an inner diameter substantially the same as the outer diameter of the optical element, and a small inner diameter portion smaller than the large inner diameter portion, and has a step portion between the two, and at the open end side of the large inner diameter portion. A thin portion bent inward by 90 ° or more is formed,
Addition to the optical element by sandwiching and fixing the flat surfaces of the incident side end surface and the output side end surface of the optical element housed in the large inner diameter portion by the step portion and the bent thin wall portion, respectively. It is possible to disperse the force and prevent the destruction of the optical element.

Further, since a joining material is not required, for example, when an adhesive is used, outgassing from the adhesive does not adversely affect other parts, and curing of the adhesive does not occur. The time required can also be reduced. Further, it is not necessary to consider deterioration of reliability due to moisture absorption of the adhesive under high temperature and high humidity.

When solder or low melting point glass is used as the bonding material, the optical element is cracked or cracked if the difference in thermal expansion coefficient between the optical element and the holder is large. Therefore, Kovar or Ni-Fe is attached to the holder. The coefficient of thermal expansion of alloys is close to that of glass,
Although it has been necessary to use a material that is expensive and difficult to cut, these problems can be avoided by the present invention, so that the cost of the material can be reduced.

Further, by eliminating the use of the low melting point glass, the lead contained in the low melting point glass is eliminated and it is possible to contribute to global environmental safety.

[Brief description of drawings]

1A is a sectional view of an optical communication component of the present invention, and FIG. 1B is a sectional view of only a holder in FIG.
(C) is a perspective view showing another embodiment of the present invention.

FIG. 2 is a sectional view showing another embodiment of the present invention.

FIG. 3 is a sectional view showing another embodiment of the present invention.

FIG. 4 is a diagram showing an assembling apparatus for an optical communication component of the present invention.

FIG. 5 is a cross-sectional view of a jig used for assembling the optical communication component of the present invention.

FIG. 6 is a sectional view of a conventional lens holder.

FIG. 7 is a sectional view of a conventional lens holder.

[Explanation of symbols]

1: Optical element 2: Holder 3: Joining material 4: Holder 5: Ball lens 6: Thin-walled cylinder 7: Step 8: Large inner diameter 9: Small inner diameter 10: Step 11: Thin part 12: Partial caulking part 13: taper shape 14: cushioning material 15: Caulking machine 16: Processing jig

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Claims (3)

[Claims] 1. An optical communication component in which an optical element having at least a part of a light incident side end surface and a light emitting side end surface being a flat surface is fixed to a holder made of metal, wherein the holder has substantially the same outer diameter as that of the optical element. A large inner diameter portion having an inner diameter and a small inner diameter portion smaller than the large inner diameter portion are provided with a step portion therebetween, and a thin portion bent inward by 90 ° or more on the open end side of the large inner diameter portion. Are formed, and the plane portions of the incident side end surface and the output side end surface of the optical element housed in the large inner diameter portion are fixed by being in surface contact with the step portion and the bent thin portion, respectively. Optical communication parts characterized by the following. 2. A component for optical communication according to claim 1, further comprising a cushioning material provided between the optical element and the holder. 3. The thin portion of the holder is 50 g to 1000 g.
The method for manufacturing a component for optical communication according to claim 1 or 2, wherein a caulking is applied with a load of g.