JP3569576B2 - Manufacturing method of optical fiber mounting module - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing an extremely small optical fiber mounting module used for transmitting various lights such as an optical communication public line, an optical computer, and a liquid crystal panel.
[0002]
[Prior art]
As computers have increased in capacity and processing speed has increased, research on optical interconnections connecting a number of arithmetic processing units with optical fibers has been progressing, and the technology has spread to various fields such as various optical computers and optical communication public lines.
[0003]
As described above, when light is used as a signal, signals can be exchanged much more efficiently than transmission using an electric signal, and there is an advantage that noise is hardly included in signal transmission and a transmission capacity is large. Since a sufficient amount of light and reliable transmission of light are required at the connection parts of devices and optical fibers, advanced technology is required to condense the light without escaping it as much as possible and transmit it to the light receiving unit. You.
[0004]
Here, FIG. 12 shows an example of the optical transmission device, and shows an array type condenser lens 03 which collects light having a wavelength of 780 to 1,650 nm oscillated from the laser diode 01 and guides the light to the optical fiber 02. ing.
[0005]
The condensing lens 03 is provided with a convex lens 031 having a diameter of about 250 μm in a line, and collects a laser beam 04 oscillated from the laser diode 01 so as to diffuse at, for example, a 50 ° angle. It is required that the light can be guided to the optical fiber 02 accurately.
[0006]
In particular, in the connection system between the optical fiber arrays as shown in the figure, if there is a variation in the center spacing between the optical fiber array and the lens array, even if the optical axis between the specific fiber and the lens is aligned, the connection between the other fiber and the lens will not occur. Axis shift occurs. In this case, the light beam from the transmission-side lens that is misaligned has its optical path inclined so as to protrude from the light-receiving side lens or protrude from the core of the optical fiber even after passing through the lens, so that the coupling efficiency to the output side fiber decreases. At present, the deviation of the center of the optical fiber array is dominant for the axis deviation between the fiber and the lens.
[0007]
[Problems to be solved by the invention]
Therefore, the optical fiber mounting in the integrated module requires high-precision positioning at the same time as fixing, and as shown in FIG. 13, V-shaped alignment grooves 051, V-shaped grooves are formed on the upper substrate 05 and the lower substrate 06 by anisotropic etching. In this case, the optical fiber 02 and solder (fixing means) are sandwiched between the upper and lower substrates 05 and 06, and the optical fibers are aligned and fixed by heating them.
[0008]
However, the etching of the V-shaped groove has a problem in terms of accuracy, and since the two substrates are bonded together, the parallelism of the two substrates and the center line of the two V-shaped grooves are difficult to match, so that the output side fiber can be formed. In addition, the coupling efficiency is reduced, and many steps are complicated in processing.
[0009]
SUMMARY OF THE INVENTION An object of the present invention is to provide a method of manufacturing an optical fiber mounting module capable of easily and accurately positioning an optical fiber.
[0015]
In the method for manufacturing an optical fiber mounted module of the present invention, the substrate is an integrated substrate made of a light-transmitting material having at least two surfaces, a light-collecting surface and a fiber take-out surface,
From the light-collecting surface of the substrate, the substrate is excavated by cutting or grinding using a blade having a higher hardness than the substrate, and excavation is performed by the blade at a predetermined depth position before the blade penetrates the substrate. Forming a lens in the substrate by stopping
And from the fiber take-out surface, using a blade of higher hardness than the substrate, drilling a hole that coincides with the central axis of the convex lens ,
Followed by forming inlet of the optical fiber is subjected to diameter expansion or chamfering using the blade or other blade to an open end of the hole, after insertion of a predetermined depth an optical fiber from said inlet, and the optical fiber It is characterized in that a space between the substrate and the inlet is filled with a joining means.
[0016]
The method for manufacturing an optical fiber mounting module according to the present invention is characterized in that at least one surface of the upper and lower surfaces of the substrate is cut or ground by cutting or grinding using a blade having a higher hardness than the substrate, and before the blade penetrates the substrate. A lens is formed in the substrate by stopping the excavation processing by the blade at a predetermined depth position, and a reference pin hole is drilled by another predetermined blade at at least two points separated by a predetermined distance from the lens. Protruding pins form a condenser lens,
From at least one of the upper and lower surfaces of another substrate, a hole having a higher hardness than the substrate and having a diameter substantially equal to the diameter of the optical fiber is formed by piercing the substrate using a blade, and a predetermined distance from the hole. Forming an optical fiber mounting board by drilling a reference pin hole or projecting a reference pin at at least two separate points with a predetermined blade,
When the reference pin hole of the condenser lens and the reference pin hole of the optical fiber mounting board are connected by a pin, or when one reference pin hole and the other reference pin are fitted, the center axis of the lens and the optical fiber mounting board are The converging lens and the optical fiber mounting board are integrated so that the center axis of the hole coincides with the center axis of the hole.
According to this feature, for example, the relative position between the lens in the condenser lens and each reference pin hole (or reference pin) and the relative position between the hole in the optical fiber mounting board and each reference pin hole (or reference pin) are determined. Each is processed using an NC machine tool or the like so as to match, and the condenser lens and the optical fiber mounting substrate are fixed with the reference pin hole and the pin (or the reference pin), thereby being fixed to the center axis of the lens. The center axis of the optical fiber can be exactly matched. It is particularly suitable when a lens array and an optical fiber array are combined.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention will be described more specifically, and the gist of the present invention is not limited to the embodiments.
[0018]
1 and 2 show a method of manufacturing an optical fiber mounting substrate, for example, using a diamond drill 2 as a blade from the upper surface (optical fiber extraction surface 9) of a silicon substrate 1 cut into a prismatic shape. Excavation is started by grinding or cutting. The material of the substrate 1 is not limited to the silicon material, but may be another material such as Kovar or quartz.
[0019]
The tip of the diamond drill 2 is a perforated portion 7 having the same width or the same diameter, and the rear portion is formed of a chamfered portion 6. In the perforated portion 7 and the chamfered portion 6, a large number of fine diamond abrasive grains are substantially uniform. Are arranged. The tip surface of the diamond drill 2 is flat. It is sufficient that the diamond drill 2 has a shape that draws an arc shape by rotating the diamond drill. Therefore, the diamond drill 2 may have a flat plate shape or a cylindrical shape. The one hole 4 is set to have a diameter (for example, about 120 μm) that is almost the same as the diameter of the optical fiber and allows a slight sliding contact.
[0020]
The important thing in this step is to form the hole 8 for positioning the optical fiber by digging the substrate 1 as shown in FIGS. 1 and 2. Although the embodiment in which the substrate 1 is rotated about the axis is shown, the present invention is not limited to this embodiment, and the substrate 1 can be rotated. In short, the diamond drill 2 or the substrate 1 is given a relative rotational motion using an NC machine tool or the like, and the diamond drill 2 or the substrate 1 is moved in the direction of the rotation axis, and the two are brought into contact with or pressed against each other. 8 can be formed.
[0021]
A second hole 5 having a larger diameter than the first hole 4 is formed as a chamfer or an enlarged diameter at the entrance of the optical fiber take-out surface 9 of the hole 8, and in this embodiment, the second hole 5 is tapered. It has a hole.
[0022]
In the process of this embodiment, the drilling is accurately stopped at a predetermined position before the diamond drill 2 penetrates the substrate 1, and the bottom surface 3 is formed. In the case where a plurality of holes 8 are formed, as shown in FIG. 2, the next similar excavation is started by changing the relative position between the substrate 1 and the diamond drill 2, that is, moving only one of them horizontally. I do. Here, for example, if the bottom surface (light-collecting surface 10) as a fixed portion in processing of the substrate 1 is horizontally processed and is accurately maintained, the distance from the bottom surface 3 of the hole 8 to the light-collecting surface 10 H can form a large number of holes 8 all of which are uniform. In this case, the central axis of the hole 8 is perpendicular to the light-collecting surface 10.
[0023]
When the substrate 1 as the optical fiber mounting substrate is fixed to a part of another transmission device, the planar accuracy and dimensions of the side, bottom, or top surface of the substrate 1 used as the fixed portion are determined in advance. It is good to give to the substrate before processing.
[0024]
Next, in order to mount and fix the optical fiber 11 on the substrate 1 thus formed, the optical fiber 11 is inserted into the hole 8 until it comes into contact with the bottom surface 3 as shown in FIG. At the time of insertion, the optical fiber 11 is guided to the second hole 5 having a large diameter as a chamfered portion or an enlarged portion at the entrance of the hole 8, and furthermore, the first hole having substantially the same diameter as the optical fiber 11. Guided to part 4.
[0025]
Therefore, the tip of each optical fiber 11 is uniformly aligned at a distance H from the light condensing surface 10, so that the positioning in the optical fiber axial direction (Z axis) is further achieved by fitting into the first hole 4. The positioning of each optical fiber 11 in the X and Y axis directions is achieved simultaneously.
[0026]
At this point, as shown in FIG. 3, the second hole 5 has a diameter larger than the diameter of the optical fiber 11, and is located between the inner peripheral surface of the second hole 5 and the outer peripheral surface of the optical fiber 11. A space is formed, and this space is filled with an adhesive means 12 such as an adhesive or solder as shown in FIG. 4 and solidified, whereby the optical fiber 11 is firmly fixed to the substrate 1 and the optical fiber mounting module is completed. . Here, as described above, the distance H between the light-collecting surface 10 and the tip of the optical fiber 11 is extremely important in terms of the positional relationship with the focal position of light collected by a lens or the like from the light-collecting surface 10 direction. is there.
[0027]
Next, FIG. 5 shows a second embodiment of the present invention. The difference from the first embodiment is that the hole 8 penetrates the substrate 1 (see FIG. 5A). The steps of attaching the optical fiber 11 to the substrate 1 in this embodiment are shown in (B) to (D). In (B), the flat plate 13 is applied to the condensing surface 10 of the substrate 1 and the optical fiber 11 is insert. In this case, as in the first embodiment, the positions of the optical fibers 11 in the X, Y, and Z-axis directions with respect to the substrate 1 are determined.
[0028]
Next, while maintaining this state, as shown in (C), the joining means 12 such as an adhesive is filled, and after the joining means 12 is solidified, the flat plate is removed as shown in (D), whereby the optical fiber is removed. The mounting module is completed.
[0029]
In this embodiment, since the tip 11 ′ of the optical fiber 11 is exposed from the substrate 1, the substrate 1 does not need to have translucency, and various inexpensive materials can be used. Further, unlike the case of the first embodiment, it is not necessary to perform a smoothing process for transmitting light on the bottom surface 3 of the hole 8.
[0030]
6 and 7 show a method of manufacturing a condenser lens and an array-type condenser lens (lens array) manufactured by this method. FIGS. 8 and 9 show this condenser lens, an optical fiber mounting board, Are connected and integrated.
[0031]
FIG. 6 shows a method of manufacturing a condensing lens. For example, a drilling process is performed by grinding or cutting from the upper surface 99 of a silicon substrate 111 cut into a prism using a diamond drill 22 as a blade. Is started.
[0032]
The vicinity of the tip of the diamond drill 22 is flat, and the tip face 55 is formed in a substantially arc shape, and a large number of fine diamond abrasive grains are arranged almost uniformly on the tip face 55 and side faces.
[0033]
By giving a relative rotational motion to the diamond drill 22 and the substrate 111 and moving the diamond drill 22 or the substrate 111 in the axial direction and contacting or pressing them, the concave shape of the distal end face 55 of the diamond drill 22 becomes convex. It is transferred into the concave portion 33 of the substrate 111 as an accurate lens 44 having a shape.
[0034]
In this step, it is necessary that the drilling be accurately stopped at a predetermined position before the diamond drill 22 penetrates the substrate 111. When a plurality of lenses are formed, the relative position between the substrate 111 and the diamond drill 22 is required. Changing the position, that is, moving either one only horizontally, starts the next similar excavation. Here, for example, if the surface opposite to the upper surface 99 as a fixed portion in the processing of the substrate 111 is horizontally processed and accurately maintained, a large number of uniform lenses are positioned at extremely accurate positions with respect to the bottom surface. 44 can be arranged. In this case, the central axis of the lens 44 is perpendicular to the bottom surface.
[0035]
Next, on the substrate 111, at least two reference pin holes 77 are drilled on the same machine tool as the lens processing machine, for example, by drilling 66, excluding the position of each lens 44 (four points in the present embodiment). ).
[0036]
Next, although not shown, the hole 8 is formed in the substrate 1 at the same interval as the distance between the center axis of the lens formed on the substrate 111 of the condenser lens and the center axis of the adjacent lens. Also, at least two reference pin holes 77 are drilled by the drill 66 on the same machine tool as the drilling (4 in this embodiment). Here, when the reference pin holes 77 of the substrates 111 and 1 coincide with each other, that is, when a plurality of pins 14 are fitted into the reference pin holes 77 as shown in FIG. The central axes match.
[0037]
In the case of the present embodiment, since the condenser lens 44, the optical fiber fixing hole 8 and the reference pin hole 77 are all formed by drilling the substrate, their positions are set to the preset NC positions. Since it is accurately determined by the drill position of the machine tool, the respective center axes of the array-type lens 44 and the array-type optical fiber 11 can be matched very accurately. Using a drill or the like, the front or rear surface of the substrate 1 is processed so that a reference pin (not shown) is integrally protruded from either the substrate 1 or the substrate 111, and fitted into the reference pin hole of one of the substrates. Is also possible.
[0038]
FIG. 9 shows another embodiment, in which the processing of the lens 44 as described above is performed with reference to the side surfaces 88 and 88 ′ of the substrate 111 of the condenser lens and the side surfaces 16 and 16 ′ of the substrate 1 for mounting an optical fiber. Then, when the hole 8 is pierced and the side surfaces 16, 16 ', 88, 88' are positioned by the pressing plate 15, the array type lens 44 and the array type optical fiber 11 are respectively similar to those in FIG. Can be aligned very accurately.
[0039]
FIGS. 10 and 11 show an optical fiber mounting substrate in which a lens 44 and a hole 8 for fixing an optical fiber are formed by drilling on the front and back surfaces of the substrate 1. A hole 8 formed of a second hole 5 having a large diameter and a first hole 4 having a diameter substantially the same as that of the optical fiber is formed on the optical fiber take-out surface 9 which is formed on the back surface and is concentric with each lens 44. It is formed.
[0040]
As described above, since one substrate 1 is positioned and drilling such as cutting and grinding is performed by NC drilling to form the lens and the hole, not only the coincidence of the optical axis but also the bottom surface of the lens 44 and the hole 8. Since the distance H ′ between the three can be set accurately, the focal position of the lens can be accurately matched with the fiber.
[0041]
As described above, the embodiments of the present invention have been described with reference to the drawings. However, the specific configuration is not limited to these embodiments, and even if there are changes and additions without departing from the gist of the present invention, they are included in the present invention. It is.
[0042]
For example, since the first hole 4 of the hole 8 only needs to support a predetermined length of the optical fiber, it is sufficient that the first hole 4 is formed in a part of the hole 8. In order to prevent the air in the hole 8 from escaping during the passage, an air passage may be appropriately provided in the inner peripheral portion of the first hole 4.
[0051]
[Brief description of the drawings]
FIG. 1 is a sectional view of a substrate being drilled by a diamond drill according to an embodiment of the present invention.
FIG. 2 is a perspective view of an optical fiber mounting board according to an embodiment of the present invention.
FIG. 3 is a cross-sectional view showing a step of mounting an optical fiber on the mounting board of FIG. 2;
FIG. 4 is a perspective view of the optical fiber mounting module after mounting and fixing the optical fiber on the mounting substrate of FIG. 2;
FIGS. 5A to 5D are cross-sectional views illustrating a process of mounting an optical fiber on a mounting board according to a second embodiment.
FIG. 6 is a perspective view of a diamond drill and a substrate when a condenser lens is manufactured.
FIG. 7 is a perspective view of the condenser lens completed in the step of FIG.
FIG. 8 is a perspective view showing a connection structure between a condenser lens and an optical fiber mounting board according to another embodiment of the present invention.
FIG. 9 is a perspective view showing a connection structure between a converging lens and an optical fiber mounting board, which is still another embodiment of FIG.
FIG. 10 is a perspective view of an optical fiber package module having a condenser lens according to still another embodiment of FIG. 9;
FIG. 11 is a sectional view taken along line BB of FIG. 10;
FIG. 12 is a perspective view illustrating an example of a conventional optical transmission device.
FIG. 13 is a sectional view of the optical fiber mounting module of FIG. 2;
[Explanation of symbols]
1 substrate 2 diamond drill (blade)
3 bottom surface 4 first hole 5 second hole 6 chamfered portion 7 perforated portion 8 hole 9 extraction surface 10 light-collecting surface 11 optical fiber 11 'tip 12 bonding means 13 flat plate 14 pin 15 holding plate 16, 16' side surface 22 Diamond drill 33 Recess 44 Lens 55 Tip surface 66 Drill 77 Reference pin holes 88, 88 'Side surface 99 Top surface 111 Substrate

Claims (2)

The substrate is an integrated substrate made of a translucent material having at least two surfaces, a light-collecting surface and a fiber take-out surface,
From the light-collecting surface of the substrate, the substrate is excavated by cutting or grinding using a blade having a higher hardness than the substrate, and excavation is performed by the blade at a predetermined depth position before the blade penetrates the substrate. Forming a lens in the substrate by stopping
And from the fiber take-out surface, using a blade of higher hardness than the substrate, drilling a hole that coincides with the central axis of the convex lens ,
Followed by forming inlet of the optical fiber is subjected to diameter expansion or chamfering using the blade or other blade to an open end of the hole, after insertion of a predetermined depth an optical fiber from said inlet, and the optical fiber A method for manufacturing an optical fiber mounting module, characterized in that a space between an inlet of a substrate and a joining means is filled. From at least one of the upper and lower surfaces of the substrate, the substrate is excavated by cutting or grinding using a blade having a higher hardness than the substrate, and excavation is performed at a predetermined depth position before the blade penetrates the substrate. By stopping the processing, a lens is formed in the substrate, and a reference pin hole is drilled with a predetermined blade or a reference pin is projected at at least two other points separated by a predetermined distance from the lens to form a condensing lens And
From at least one of the upper and lower surfaces of another substrate, a hole having a higher hardness than the substrate and having a diameter substantially equal to the diameter of the optical fiber is formed by piercing the substrate using a blade, and a predetermined distance from the hole. Forming an optical fiber mounting board by drilling a reference pin hole or projecting a reference pin at at least two separate points with a predetermined blade,
When the reference pin hole of the condenser lens and the reference pin hole of the optical fiber mounting board are connected by a pin, or when one reference pin hole and the other reference pin are fitted, the center axis of the lens and the optical fiber mounting board are A method for manufacturing an optical fiber mounting module, wherein a converging lens and an optical fiber mounting substrate are integrated so that the central axis of the hole coincides with the center axis of the hole.

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