JP2524275B2 - Optical component-optical fiber alignment method and optical component - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alignment method for aligning the optical axes of an optical component such as an optical IC and an optical fiber when they are connected.

[0002]

2. Description of the Related Art In connecting an optical component and an optical fiber, it is necessary to align the optical axes of these components with high precision. A method is used in which a state in which the optical axis of the light emitted from the optical axis coincides with the optical axis of the other is obtained by searching the maximum value of the optical power from the other.
In order to perform such precise alignment by measuring the optical power, generally, coarse alignment is performed prior to this so as to obtain the optical power.

A conventional coarse alignment method will be described with reference to FIG. Note that FIG. 5 shows each connection portion between the optical IC 11 and the optical fiber 12. A fine optical waveguide 13 having one end on one end face 11a is formed on the surface of the optical IC 11, and a pair of parallel markers 14 indicating the position of the optical waveguide 13 are provided so that the position of the optical waveguide 13 can be easily recognized. The center axis of the parallel marker 14, that is, the center axis of the pair of parallel markers 14 is aligned with the optical waveguide 13, and is provided at the end of the surface of the optical IC 11. The end of the optical fiber 12 is the carrier 1
5, the end face of the optical fiber 12 is exposed at the end face 15 a of the carrier 15. The end faces of the marker 14 and the optical fiber 12 of the optical IC 11 are observed from the X-axis direction and the Y-axis direction, respectively.
To move the optical IC 11 and the carrier 15 relative to each other by moving the stage (not shown) respectively installed therein to align the positions of the center axes of the pair of markers 14 and the center of the optical fiber 12. Thus, the optical axes of the end face of the optical waveguide 13 of the optical IC 11 and the end face of the optical fiber 12 are roughly aligned.

[0004]

By the way, FIG. 5 (A)
As shown in FIG. 6, the end surface 11a of the optical IC 11 is a surface inclined with respect to the extending direction of the optical waveguide 13 to prevent reflected light. Similarly, the end surface 15a of the carrier 15 that holds the end portion of the optical fiber 12 is also formed. The surface is inclined with respect to the extending direction of the optical fiber 12. Therefore, for example, the optical path 16 of the emitted light emitted from the optical fiber 12 is shown in FIG.
Even if the position of the center axis of the marker 14 is aligned with the center of the optical fiber 12 in the X-axis direction,
The optical path 16 is displaced from the end face of the optical waveguide 13.

Therefore, in order to perform precise alignment by measuring the optical power, an optical IC for making the optical power available
In the coarse alignment between the optical fiber 11 and the optical fiber 12, the optical IC 1
The marker 14 of No. 1 is only a rough guide, and the optical IC 11 and the optical fiber 12 must be relatively moved over a wide range to search for a position where the optical power can be obtained, which is difficult and extremely poor in workability. It was.

An object of the present invention is to provide a centering method which eliminates the conventional drawbacks and can be performed extremely easily.

[0007]

The present invention has substantially the same XZ.
The optical component having the optical waveguide and the marker in the plane and the end portion of the optical fiber are relatively moved in the XZ plane, and in the state where they are arranged in the Z-axis direction, the optical component and the end face of the optical waveguide are arranged. Optical component that aligns the optical axis with the end face of the optical fiber −
In the optical fiber alignment method, the distance d in the Z-axis direction between the optical component and the optical fiber is set to the following value, and d = W {tan (π / 2−α + β) −tanβ} W: marker of the optical component and its light guide Vertical spacing between the center of the waveguide, α: incident angle of light with respect to the optical component, β: its refraction angle, and then aligning by aligning the position of the optical fiber center with the marker of the optical component, The optical component used in this alignment direction is provided with only one marker which is separated from this one optical waveguide at one end thereof.

[0008]

According to the present invention having the above-described structure, the distance between the optical component and the optical fiber in the Z-axis direction is set to a predetermined value d, and the positions of the optical fiber center and the marker of the optical component are matched with each other, thereby The optical axes of the component and the optical fiber are aligned.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, an optical waveguide 22 having one end on one end face 21a thereof is formed on the surface of the optical IC 21, and a marker 23 is formed at a position apart from the optical waveguide 22 in the present invention. In this embodiment, the marker 23 is a line drawn from the end face 21a of the optical IC 21 in parallel with the optical waveguide 22. In FIG. 1, the extension direction of the optical waveguide 22 is the Z axis, and the long side direction of the end face 21a of the optical IC 21 that is inclined with respect to the Z axis is the X axis.

In order to align the optical axes of the end face of the optical waveguide 22 of the optical IC 21 and the end face of the optical fiber 12, first, the optical IC 21 and the carrier 15 holding the end portion of the optical fiber 12, for example, By moving the respective stages (not shown) installed, they are relatively moved in the XZ plane and arranged in the Z-axis direction. In the rough alignment prior to the precision alignment by measuring the optical power, it is necessary to have a positional relationship such that the light emitted from one of the optical IC 21 and the optical fiber 12 enters the other in order to obtain the optical power. . Now, in FIG. 1, the center of the optical fiber 12 exposed on the carrier end face 15a and the marker 23 are located on the same straight line parallel to the Z axis, and the light emitted from the optical fiber 12 enters the end face of the optical waveguide 22. It is assumed that the optical IC 21 and the optical fiber 12 are arranged in such a positional relationship that the optical path of the incident light coincides with the extension direction of the optical waveguide 22. At this time, the distance in the Z-axis direction between the optical IC 21 and the optical fiber 12 is d, the vertical distance between the marker 23 of the optical IC 21 and the center of the optical waveguide 22 is W, the optical waveguide 22 and the marker 2 are
Assuming that the distance in the Z-axis direction between the two ends located on the end face 21a of the optical IC 21 of No. 3 is m, the incident angle of light on the optical IC 21 is α, and the refraction angle of the light incident on the optical IC 21 is β, As shown in detail in (B), it is expressed as tan β = m / W ... tan (π / 2−α + β) = (d + m) / W ... From these equations, d = W {tan (π / 2 -[Alpha] + [beta])-tan [beta]} is represented.

That is, the distance d in the Z-axis direction between the optical IC 21 and the optical fiber 12 is set to a value represented by the equation, and then the center of the optical fiber 12 on the carrier end face 15a and the optical IC 21.
By matching the position of the marker 23 viewed from the Z-axis direction, the optical axes of the end surface of the optical waveguide 22 of the optical IC 21 and the end surface of the optical fiber 12 can be roughly aligned.

FIG. 2 shows an example of an aligning device for performing the above-described coarse alignment, which is the optical waveguide 2 of the optical IC 21.
The optical fibers 12 whose ends are held by the carrier 15 are aligned at both the input and output ends of the optical fiber 2. Optical IC2
1 is positioned and fixed on the fixed base 24. On both sides of the fixed base 24, aligning stages 25 and 26 that can move with high precision in three directions of the X-axis direction, the Y-axis direction, and the Z-axis direction are arranged, and the carrier 1 of the optical fiber 12 is placed thereon.
5 is installed.

Alignment on the one end face 21a side of the optical IC 21 using this aligning device will be specifically described. As shown in FIG. 3, the microscope 27 is positioned at a position 28 immediately above the optical IC 21 and the carrier 15 in the Y-axis direction to observe them, and the distance between the optical IC 21 and the optical fiber 12 in the Z-axis direction is adjusted. 25 is moved in the Z-axis direction to set the distance d represented by the equation.

Next, the stage 29 on which the microscope 27 is installed is moved to move the microscope 27 in the Z-axis direction,
As shown in FIG. 3, a position 31 directly above the reflecting mirror 30 installed so that the carrier end surface 15a can be observed obliquely.
The optical fiber 12 and the end of the surface of the optical IC 21 are observed at the same time, and the aligning stage 25 is moved in the X-axis direction, so that the position of the center of the optical fiber 12 and the marker 23 is adjusted. Position on the same straight line parallel to the Z-axis. FIG. 4 shows an image at this time projected on the monitor 33 connected to the microscope 27 via the video camera 32. By using the cursor line 34 projected on the monitor, the center of the optical fiber 12 is shown. And marker 23
Is being aligned with. Each part on the image shown in FIG. 4 has the same reference numeral as the subject.

In this alignment, the aligning stage 25 moves in the X-axis direction, that is, in the direction parallel to the optical IC end face 21a, so that the Z-axis set ahead of the optical IC 21 and the optical fiber 12 is caused by the movement. The directional distance d does not change. In this way, the alignment stage 25 is moved in the Z-axis direction and the X-axis direction, and the alignment stage 25 is moved in the Y-axis direction in a state where the alignment of the optical IC 21 and the optical fiber 12 in those directions is completed. Optical IC2
The position where the light emitted from one of the optical fiber 12 and the optical fiber 12 enters the other can be easily obtained.

Alignment on the other end of the optical waveguide 22, that is, on the other end face 21b side facing the one end face 21a of the optical IC 21 can be performed in the same manner.
A marker is provided on the other end of the marker at a predetermined distance from the center thereof.

[0017]

As described above, according to the present invention,
The optical component is provided with a marker apart from the optical waveguide, and the distance W between them, the light incident angle α to the optical component and the refraction angle β thereof
Then, the distance d is calculated by the following formula: d = W {tan (π / 2−α + β) −tanβ} The optical component and the optical fiber are arranged in the Z-axis direction, and the value of the distance between them is defined as d. By aligning the position of the fiber center with the marker of the optical component, it is possible to align the optical axis between the end face of the optical waveguide of the optical component and the end face of the optical fiber, and perform precise alignment by measuring the optical power. The preceding rough alignment can be performed extremely easily.

[Brief description of drawings]

FIG. 1A is a diagram for explaining an embodiment of an optical component-optical fiber alignment method according to the present invention. (B) is (A)
Detailed view of the main part of.

FIG. 2 is a perspective view showing an example of an aligning device using the aligning method according to the present invention.

FIG. 3 is a diagram for explaining a method of observing an optical component and an optical fiber with a microscope.

FIG. 4 is a diagram showing a monitor image when an end face of an optical fiber and an end portion of an optical component are observed.

FIG. 5A is a plan view for explaining a conventional centering method. (B) is a side view of (A).

[Explanation of symbols]

 12 optical fiber 15 carrier 21 optical IC 22 optical waveguide 23 marker

Claims (2)

(57) [Claims] 1. An optical component having an optical waveguide and a marker and an end portion of an optical fiber are relatively moved in the XZ plane in substantially the same XZ plane, and they are arranged in the Z-axis direction. In the optical component-optical fiber alignment method for aligning the optical axes of the end face of the optical waveguide of the optical component and the end face of the optical fiber, the distance d in the Z-axis direction between the optical component and the optical fiber is set to the following value. , D = W {tan (π / 2−α + β) −tanβ} W: vertical distance between the marker of the optical component and the center of the optical waveguide, α: incident angle of light with respect to the optical component, β: refraction thereof Angle, and then aligning the position of the center of the optical fiber with the position of the marker of the optical component-optical component-optical fiber alignment method. 2. An optical component used in the aligning method according to claim 1, wherein one optical waveguide at one end of the optical component is provided with only one marker distant from the optical waveguide. parts.