JPS6296912A - Fixing structure for optical lens - Google Patents

Abstract

PURPOSE:To easily constitute a collimating optical system by forming aperture parts having a spread where ball lenses are arranged and groove parts where optical waveguide parts are provided on a substrate. CONSTITUTION:An aperture part 5 having an equilateral triangle-shaped spread to which a ball lens 3 is inserted and a groove part 6 to which a ferrule 2 projecting an optical fiber 1 as optical waveguide parts is inserted are formed on a substrate 4. An aperture part 5' and a groove part 6' constituted similarly are formed in the counter side of the ball lens 3 in a recessed part 10, and a ball lens 3' and a ferrule 2' protecting an optical fiber 1' are provided. When the ball lens 3 is inserted to the equilateral triangle-shaped aperture part 5 and the ferrule 2 of the optical fiber 1 is inserted to the groove part 6, they are positioned accurately, and they are stuck by proper means. If a detaining part B projected a length d1 from the ferrule 2 having a width (d) is formed, the optical fiber 1 and the ball lens 3 are very easily and accurately positioned.

Description

[Detailed Description of the Invention] [Table of Contents] Overview Industrial Application Fields Prior Art (Figures 4 to 6) Problems to be Solved by the Invention Means for Solving the Problems (Figure 1) Effects Embodiment (FIGS. 2 and 3) Effects of the invention [Summary] In order to accurately connect an optical fiber to an optical device, a hole-shaped portion is formed in a substrate, and the shape of this hole-shaped portion is adjusted to match the outer periphery of a spherical lens. Two points on the surface are in contact with the substrate at the same height, and the shape is an isosceles triangle with the line connecting these two points as the base and the apex on the perpendicular line that coincides with the center of the spherical lens.

[Industrial application field]

The present invention relates to a structure for fixing an optical lens in an optical system using an optical fiber, and particularly to a structure in which a groove is provided in a substrate for holding a ball lens, and a ball lens constituting a parallel optical system is held within the groove.

[Conventional technology]

Optical fibers are used in optical communications, etc., but in order to use these optical fibers to branch, combine, block, or pass light of specific wavelengths. As shown in FIG. 4, a parallel optical system is used to perform the various functions described above.

That is, lenses 23 and 25 are arranged between the optical fibers 21 and 22 to make the light into a parallel optical system, and a half mirror 24 is arranged between the optical fibers 21 and 22.
If the optical fiber 21 is inserted, the light transmitted from the optical fiber 21 is split by the half mirror 24, the split light is focused by the lens 28, and the split light is guided to, for example, a monitor device by the optical fiber 27. Also, if a filter is used instead of the half mirror 24, it becomes possible to pass or reflect light of a specific wavelength, or to allow only light of a specific wavelength to pass. The output light spreads at an aperture angle determined by the ratio of the refractive index of the optical fiber 21 to the refractive index of air, so it is made into a parallel beam by the lens 23, focused by the lenses 25 and 28, and sent to the optical fiber 2.
This will lead to 2.27. Using this parallel optical system, various optical devices such as splitters and couplers can be constructed.

When creating this optical device, as shown in FIG. Fixed to. Then, a plurality of such cylindrical lens holders 31 held by metal holders 33 are prepared and placed on the substrate 35 with metal spacers 34 interposed therebetween, as shown in FIG. 6, 18+. do. At this time, in order to align the optical axes 11β' of the lens holders 31 and 31', as shown in FIG.
After adjusting the optical axes 1 and 12' so that they are aligned by changing the insertion state of the holders, the holders, spacers, substrates, etc. are fixed by a fixing means such as laser welding.

[Problems to be solved by the invention] As described above, conventionally, when constructing a parallel optical system, a plurality of parts are assembled, positioned, and then fixed, so it takes a considerable amount of time to assemble an optical device. There was a problem in that it required a lot of effort and time. When configuring a splitter or the like by arranging a filter or the like in a parallel optical system, the number of parts to be arranged increases further, making it much more troublesome.

SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide an optical lens fixing structure that allows a parallel optical system to be easily constructed.

[Means for solving problems]

In order to achieve the above object, the present invention, as shown in FIG. A groove 6 is formed into which a ferrule 2 is inserted to protect the ferrule. A similar opening and groove are formed on the opposite side of the recess 10 to the ball lens 30, and a ferrule 2' for protecting the ball lens 3' and the optical fiber 1' is provided.

[Effect]

According to the present invention, by inserting the ball lens 3 into the isosceles triangular opening 5 and inserting the ferrule 2 of the optical fiber 1 into the groove 6, these can be accurately positioned. It can be fixed by any means. In addition,
As shown in Fig. 1 (B in Ml), if a protruding portion is formed that protrudes by a distance d greater than the width d of the ferrule 2, the position of the optical fiber 1 and the ball lens 3 can be positioned extremely easily and accurately. can.

〔Example〕

The structure of one embodiment of the present invention will be described with reference to FIGS. 2 and 3 and other figures.

Figure 2 is a configuration diagram of one embodiment of the present invention in a turnout;
The figure is an explanatory diagram of the manufacturing process.

In the figure, the same reference numerals as in other figures indicate the same parts, 11 is an optical fiber, 12 is a ferrule, 13 is a ball lens, 14 is a substrate, 16 is a groove, 17 is a mirror, 1 is a dielectric multilayer film,
9.19' is a groove into which the mirror 17 is inserted, and 20 is a recess.

The optical fiber 11 transmits the branched light reflected from the mirror 17, and is fixed to the ferrule 12 with an adhesive like other optical fibers.

The substrate 14 is formed with grooves 6.6' and 16 into which the ferrules 2.2' and 12 are inserted and fixed, grooves 19 and 19' into which the mirror 17 is inserted, and a recess 20, and is made of, for example, photosensitive glass, which will be described later. has been done.

In the recess 20, as shown in FIG. 1 ta+, for example, three openings are formed, each having an isosceles triangular shape in which the ball lenses 3, 3' and 13 are arranged. Locking portions B are formed in these openings, and by locking the tip of the ferrule with the locking portions B, the tip of the optical fiber can be positioned.

The mirror 17 is provided with a dielectric multilayer film 18 as is well known, and the amount of branching can be controlled depending on the material, number of layers, and film thickness.

Therefore, as shown in FIG.
After fixing ferrules 2.2' and 1 with adhesive,
2 and fix it with glass solder, for example. Also, the ball lenses 3, 3' and 13 are also arranged as shown in FIG. 2 (al) and fixed with glass adhesive. ’ and secure in the same way.

As a result, an optical system is formed as shown in FIG.
' and is introduced into the optical fiber 1', but part of it is reflected by the mirror 17 and branched into the optical fiber 11 by the ball lens 13.

In addition, as shown in FIG.
The tip of is located. Also, an opening 5 in an isosceles triangular shape
The apex point C of is located closer to the optical fiber 1 than the focal point of the ball lens 3 (on the contrary, the focal point of the ball lens 3 is inside the apex point C), and the ball lens 3 is in contact with the aperture 5. The contact positions are at the same height with respect to the substrate 4, and the isosceles triangle is formed with the line connecting these contact positions as the base. The apex is on a perpendicular line to the base passing through the center of the spherical lens 3. Further, the groove 6 is processed to be parallel to the center line of the ball lens 3, and the center of the optical fiber 1, that is, the optical waveguide component is located at the focal position of the ball lens 3, and the groove 6
is processed so as to fit with the outer shape of the ferrule 2 that protects and fixes the optical fiber 1.

Next, when photosensitive glass is used as the substrate 14 as shown in FIG.
A method of forming the recessed portion 20 will be explained based on FIG.

Here, as the photosensitive glass, for example, silicate glass in which metal ions and a sensitizer are added and dissolved is used. This glass is sensitive to ultraviolet light, and a heat development process produces metal colloids, which serve as nuclei to grow crystals. These crystals are extremely fine and easily soluble in acid, making it possible to process them into minute shapes such as holes, grooves, and external shapes of complex shapes.
It is also possible to taper the hole or drill the hole at an angle.

(2) A mask with the pattern of each portion described above is placed on a substrate G made of photosensitive silicate glass, and a latent image is created in the glass substrate by irradiating it with ultraviolet rays.

(2) Heat treatment is performed to crystallize the photosensitive area, that is, the latent image area, making it easier to dissolve in acid. Note that the unexposed portions are also irradiated with ultraviolet rays as a pre-process for later crystallization.

■ Dissolve and remove the crystallized portion with acid. Further, the depth of the hole can be adjusted by adjusting the etching time.

■ The etched material is crystallized by heat treatment. This makes it no longer sensitive to light and has excellent physical and chemical durability.

When etching grooves of different depths, first expose with a mask pattern of only deep grooves and perform the etching process as described above, then expose with a mask pattern of shallow grooves and deep grooves, and perform the etching process in the same way. do.

Although the above example uses glass solder to fix each part, it is of course possible to use adhesive. Furthermore, if the glass substrate is plated, it is also possible to perform partial laser welding.

Furthermore, the substrate is not limited to glass, but may also be made of metal and have similar grooves or recesses formed therein.

〔Effect of the invention〕

According to the present invention, since grooves and recesses are formed in advance on the substrate to facilitate placement of optical fibers, ball lenses, etc., it is possible to assemble the optical device very easily.

[Brief explanation of drawings]

Figure 1 is a diagram of the principle of the present invention. FIG. 2 is a configuration diagram of an embodiment of the present invention. Figure 3 is an explanatory diagram of the manufacturing process of the board, Figure 4 is an explanatory diagram of the turnout; Figure 5 is an explanatory diagram of the lens holder. FIG. 6 shows a conventional example.

Claims (1)

[Claims] An opening (5) having a divergence angle in which a spherical lens is disposed on a substrate;
Fixing of an optical lens, characterized in that a groove (6) is formed in which an optical waveguide component is installed, and a joining part between the opening and the groove becomes a focal point of a spherical lens, and the tip of an optical waveguide is set at this part. structure.