JPH06222228A - Optical waveguide type element - Google Patents

Abstract

PURPOSE:To provide an optical waveguide type element capable of connecting an optical fiber to an optical waveguide in a short time without using any special connecting element. CONSTITUTION:An electrode for optical waveguide 13 and a positioning marker for optical fiber 11 are formed simultaneously on an optical waveguide forming substrate 10 on which an optical waveguide 12 is formed. The positioning marker for optical fiber 11 is installed on both sides of the optical waveguide 12, and the interval between these markers 11 is approximately the same as the diameters of an incoming side optical fiber 20 and an outgoing side optical fiber 40. Then the incoming side optical fiber 20, outgoing side optical fiber 40, and positioning marker for optical fiber 11 are inspected visually by a microscope to position the incoming side optical fiber 20, outgoing side optical fiber 40, and optical waveguide 12 respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical waveguide type device,
In particular, the present invention relates to an optical waveguide type device in which an optical waveguide coupled to an optical fiber is formed on an optical waveguide forming substrate.

[0002]

2. Description of the Related Art In an optical communication system or the like, an optical fiber for transmitting light,
Optical waveguide type elements for performing light intensity modulation, phase modulation, light switching, etc. are used in combination with each other.

The optical waveguide type element is an optical waveguide selectively formed on one main surface of an optical waveguide forming substrate made of LiNbO ₃ or the like, and an optical waveguide selectively formed on the surface of the optical waveguide forming substrate. And an electrode for.

The electrode for the optical waveguide is used to cause a change in the refractive index around the electrode by applying an electric field to the electrode, and as a result, to perform switching and modulation of light.

An optical fiber is coupled to the optical waveguide,
In order to perform this coupling with low loss, it is necessary to position the optical waveguide and the optical fiber with high accuracy at the submicron level.

Conventionally, as one method of performing this positioning, the optical fiber has been positioned while observing the optical waveguide directly from the upper surface of the optical waveguide forming substrate with a microscope. However, since the optical waveguide formed by the Ti diffusion method or the proton exchange method on the optical waveguide forming substrate made of LiNbO ₃ or the like is very difficult to see, it is difficult to position the optical fiber by this method.

Therefore, the optical fiber is scanned at the end face of the optical waveguide forming substrate, and the optimum position is searched for while observing the light intensity or the light spot pattern of the emitted light at the end portion on the opposite side of the optical waveguide. The method of positioning with the optical fiber is adopted.

FIG. 2 is a schematic diagram for explaining this conventional method.

First, as shown in FIG. 2A, the incident side optical fiber 20 is horizontally oriented at the end face 15 of the optical waveguide forming substrate 10 on which the optical waveguide 12 and the optical waveguide electrode 13 are formed.
The light emitted from the end portion of the optical waveguide 12 of the end face 16 on the opposite side of the optical waveguide forming substrate 10 is detected through the lens 30 and the CCD camera 60, and the emitted light is observed. The optimum position of the incident side optical fiber 20 is searched for while observing as the outgoing light spot 80 on the monitor 70, and the position of the incident side optical fiber 20 is roughly adjusted. The diameter of the light spot emitted from the end face 16 of the optical waveguide 12 is 5 to 10 μm, while
Since the diameter of the light receiving area of the CCD camera 60 is 250 μm, the CCD camera 60 can be easily positioned.

Then, as shown in FIG. 2B, the lens 3
0, CCD camera 60 and monitor 70 for observing emitted light
Is replaced with a combination of the output side optical fiber 40 and the optical power meter 50, and the end face 1 of the optical waveguide forming substrate 10 is replaced.
6, the emission side optical fiber 40 is scanned in both the horizontal direction 91 and the vertical direction 92, and while the light intensity of the emission light from the emission side optical fiber 40 is measured by the optical power meter 50, the value of the optical power meter 50 is First, the position of the emission side optical fiber 40 is roughly adjusted so that the maximum, and then the incidence side optical fiber 20 and the emission side optical fiber 40 are finely scanned in both the horizontal direction 91 and the vertical direction 92. While measuring the light intensity of the outgoing light from the outgoing side optical fiber 40 by the optical power meter 50, the position of the incoming side optical fiber 20 and the outgoing side optical fiber 40 is adjusted so that the value of the optical power meter 50 becomes maximum. I was fine-tuning.

In this method, as shown in FIG. 2A, the emitted light spot 8 is detected by the emitted light observation monitor 70.
It is necessary to scan the incident side optical fiber 20 over the end surface 15 of the optical waveguide forming substrate 10 while observing 0, and as shown in FIG.
Since it is necessary to scan the emission side optical fiber 40 over the end surface 16 of the optical waveguide forming substrate 10 in a wide range while measuring the light intensity of the emission light from the side, the incidence side optical fiber 20 and the emission side. Optical fiber 4
There is a problem that it takes time to roughly adjust the position of 0.

On the other hand, it has been proposed to use a connecting element using a guide pin and a V-groove to connect an optical fiber and an optical waveguide without adjustment (for example, a technical research report of the Institute of Electronics, Information and Communication Engineers). CPM 92-84, 115-1
(See p. 20, 1992), there is a problem that it is difficult to produce such a connecting element because the submicron positional accuracy is required between the optical fiber and the optical waveguide and the guide pin and the V groove. .

Therefore, it is an object of the present invention to provide an optical waveguide type device capable of coupling an optical fiber and an optical waveguide in a short time without using a special connecting element.

[0014]

According to the present invention, in an optical waveguide type device in which an optical waveguide to be coupled with an optical fiber is formed on an optical waveguide forming substrate, the optical waveguide forming substrate is provided with the optical fiber. An optical waveguide device having a positioning marker is obtained.

The optical fiber positioning marker is preferably on one main surface of the optical waveguide forming substrate on which the optical waveguide is formed, and in the vicinity of an end portion of the optical waveguide to which the optical fiber is coupled. It is provided in.

More preferably, the optical fiber positioning marker is formed at the same time as the optical waveguide electrode of the optical waveguide element using the same mask.

Still more preferably, the fiber positioning marker is composed of two patterns provided on both sides of the optical waveguide to which the optical fiber is coupled and at a distance substantially the same as the diameter of the optical fiber.

[0018]

In the present invention, in the optical waveguide type device in which the optical waveguide to be coupled with the optical fiber is formed on the optical waveguide forming substrate, the optical fiber forming substrate is provided with the optical fiber positioning marker. , The optical fiber can be positioned with respect to this positioning marker. Therefore, not only can the optical waveguide and the optical fiber be coupled without using a special connection element, but the optical fiber can be attached to the end face of the optical waveguide forming substrate while observing the emitted light spot and measuring the light intensity of the emitted light. Since it is not necessary to scan over a wide area, the position of the optical fiber can be adjusted in a short time. Further, by performing image processing on the optical fiber positioning marker, automatic alignment can be easily performed.

The positioning marker for the optical fiber is
By providing the optical waveguide forming substrate on one main surface where the optical waveguide is formed and near the end of the optical waveguide to which the optical fiber is coupled, the positioning of the optical waveguide and the optical fiber can be made easier. Like

Further, by simultaneously forming the optical fiber positioning marker and the optical waveguide electrode of the optical waveguide type element using the same mask, it is not necessary to additionally provide a step for providing the optical fiber positioning marker. It is not necessary to separately provide a mask for the positioning marker for the optical fiber. Therefore, even if the optical fiber positioning marker is provided, the manufacturing cost does not particularly increase.

Not only that, the optical fiber positioning marker and the optical waveguide electrode of the optical waveguide type element are simultaneously formed by using the same mask, so that the optical fiber positioning marker can be accurately positioned with respect to the optical waveguide. Can be provided. That is, the optical waveguide electrode is positioned with respect to the optical waveguide with submicron accuracy,
If the optical fiber positioning marker is formed at the same time using the same mask as the optical waveguide electrode, the optical fiber positioning marker is also positioned with respect to the optical waveguide with submicron accuracy.

Further, the optical fiber positioning marker is composed of two patterns which are provided on both sides of the optical waveguide to which the optical fiber is coupled and which are spaced apart by substantially the same distance as the diameter of the optical fiber. It becomes possible to more easily position the optical waveguide and the optical fiber.

[0023]

Embodiments of the present invention will now be described with reference to the accompanying drawings.

FIG. 1 is a schematic diagram for explaining an optical waveguide type device according to an embodiment of the present invention and a method for positioning an optical waveguide and an optical fiber using the optical waveguide type device.

First, Ti is diffused on the optical waveguide forming substrate 10.
The optical waveguide 12 selectively by the ion exchange method or the proton exchange method
To form. The substrate 10 for forming the optical waveguide is made of LiN.
bO ₃A substrate is used.

Next, a Cr layer (not shown) is formed on the optical waveguide forming substrate 10 on which the optical waveguide 12 is formed, and Cr is formed.
An Au layer (not shown) is formed on the layer, and a photoresist layer (not shown) is formed on the Au layer. Then, the same mask is used to simultaneously form an optical waveguide electrode forming pattern and an optical fiber positioning marker pattern on the photoresist layer. Next, the Au layer and the Cr layer are etched using the photoresist layer as a mask to simultaneously form the optical waveguide electrode 13 and the optical fiber positioning marker 11. As described above, in this embodiment, the optical waveguide electrode 13 and the optical fiber positioning marker 11 are formed by the etching method.
It can be formed at the same time using the same mask.

The optical fiber positioning marker 11 is provided near the end of the optical waveguide 12 on the end face 15 side of the optical waveguide forming substrate 10 and near the end of the optical waveguide 12 on the end face 16 side of the optical waveguide forming substrate 10. Has been. The optical fiber positioning markers 11 are provided on both sides of the optical waveguide 12 on either side, and the distance between them is substantially the same as the diameter of the incident side optical fiber 20 and the emitting side optical fiber 40 to be coupled to the optical waveguide 12 later. .

Next, the incident side optical fiber 20 and the optical fiber positioning marker 11 are visually observed with a microscope,
The positions of the incident side optical fiber 20 and the optical waveguide 12 are roughly adjusted, and the emitting side optical fiber 40 and the optical fiber positioning marker 11 are visually observed with a microscope to check the positions of the emitting side optical fiber 40 and the optical waveguide 12. Make coarse adjustments. In this embodiment, the optical waveguide forming substrate 1
Since the optical fiber positioning marker 11 is provided on the position 0, rough adjustment of this position can be easily performed in a short time.

The optical fiber positioning marker 11
However, since the optical waveguides 12 are provided on both sides and the distance between them is almost the same as the diameter of the incident side optical fiber 20 and the emission side optical fiber 40, this positioning operation can be performed more easily.

After the coarse adjustment of the positions of the incident side optical fiber 20 and the emitting side optical fiber 40 in this way, the incident side optical fiber 20 and the emitting side optical fiber 40 are performed.
Is finely scanned in both the horizontal direction 91 and the vertical direction 92, and while measuring the light intensity of the outgoing light from the outgoing side optical fiber 40 by the optical power meter 50, the value of the optical power meter 50 is maximized. , Incident side optical fiber 2
The positions of 0 and the output side optical fiber 40 are finely adjusted.

As described above, in this embodiment, the incident side optical fiber 20, the emitting side optical fiber 40, and the optical fiber positioning marker 11 are visually observed with a microscope to determine the incident side optical fiber 20 and the emitting side optical fiber 40. Since the positions of the optical waveguide 12 and the incident side optical fiber 20 and the emitting side optical fiber 40 can be roughly adjusted only by aligning the optical fiber positioning markers 11 with each other, the emitted light spot can be monitored with the emitted light observation monitor. While observing using 70, it is necessary to scan the incident side optical fiber 20 over the end surface 15 of the optical waveguide forming substrate 10 in a wide range, and the light intensity of the emitted light from the emitting side optical fiber 40 is measured by the optical power meter 50. However, it is not necessary to scan the emitting side optical fiber 40 over the end surface 16 of the optical waveguide forming substrate 10 in a wide range. Ri, therefore, it becomes possible to position the incident-side optical fiber 20 and the output side optical fiber 40 in a short time.

[0032]

According to the present invention, in the optical waveguide type device in which the optical waveguide to be coupled with the optical fiber is formed on the optical waveguide forming substrate, the optical fiber forming substrate is provided with the optical fiber positioning marker. Therefore, the optical fiber can be positioned with respect to this positioning marker. Therefore, not only can the optical waveguide and the optical fiber be coupled without using a special connection element, but the optical fiber can be attached to the end face of the optical waveguide forming substrate while observing the emitted light spot and measuring the light intensity of the emitted light. Since it is not necessary to scan over a wide area, the position of the optical fiber can be adjusted in a short time. Further, by performing image processing on the optical fiber positioning marker, automatic alignment can be easily performed.

The positioning marker for the optical fiber is
By providing the optical waveguide forming substrate on one main surface where the optical waveguide is formed and near the end of the optical waveguide to which the optical fiber is coupled, the positioning of the optical waveguide and the optical fiber can be made easier. Like

Further, by simultaneously forming the optical fiber positioning marker and the optical waveguide electrode of the optical waveguide type element using the same mask, the optical fiber positioning marker can be provided without increasing the manufacturing cost. Not only can this be done, but the positioning marker for the optical fiber can be provided to the optical waveguide with high positional accuracy.

Furthermore, the positioning marker for the optical fiber is composed of two patterns provided on both sides of the optical waveguide to which the optical fiber is coupled, with a spacing substantially the same as the diameter of the optical fiber. The positioning of the optical waveguide and the optical fiber can be performed more easily.

[Brief description of drawings]

FIG. 1 is a schematic diagram for explaining an optical waveguide type device according to an embodiment of the present invention and a method for positioning an optical waveguide and an optical fiber using the optical waveguide type device.

FIG. 2 is a schematic diagram for explaining a conventional method for positioning an optical waveguide and an optical fiber.

[Explanation of symbols]

 10 ... Optical waveguide forming substrate 11 ... Optical fiber positioning marker 12 ... Optical waveguide 13 ... Optical waveguide electrode 15, 16 ... End face 20 ... Incident side optical fiber 30 ... Lens 40 ... Emission side optical fiber 50 ... Optical power meter 60 … CCD camera 70… Monitor for outgoing light observation 80… Spot for outgoing light

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuya Ejiri 1-36 Yagoto-cho, Kasugai-shi, Aichi

Claims (4)

[Claims] 1. An optical waveguide type device in which an optical waveguide to be coupled with an optical fiber is formed on an optical waveguide forming substrate, wherein the optical fiber forming marker is provided on the optical waveguide forming substrate. Optical waveguide device. 2. The optical waveguide device according to claim 1, wherein
The optical fiber positioning marker is provided on one main surface of the optical waveguide forming substrate on which the optical waveguide is formed and in the vicinity of an end portion of the optical waveguide to which the optical fiber is coupled. An optical waveguide type device characterized by: 3. The optical waveguide device according to claim 2,
The optical waveguide type element, wherein the optical fiber positioning marker is formed simultaneously with the optical waveguide electrode of the optical waveguide type element using the same mask. 4. The optical waveguide type element according to claim 2, wherein the optical fiber positioning markers are provided on both sides of the optical waveguide to which the optical fiber is coupled with a distance substantially equal to a diameter of the optical fiber. An optical waveguide device comprising two patterns provided.