JP2003255190A - Method and apparatus for adjusting focus and optical axis of lens - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for lens focus and optical axis adjustment which enables efficient focus adjusting and optical axis adjusting operations by making it possible to adjust the focus and optical axis of a lens of an optical component such as an optical fiber collimator at the same time. <P>SOLUTION: A half-mirror 22 is arranged between the optical fiber collimator 1 and a beam profiler (light beam detecting device) 4. An optical coupler 23 is installed halfway in an optical fiber 2 which guides the light from a light source 3 to a lens 7 and a power monitor (light intensity detecting device) 25 is connected to a branch optical fiber 24 from the optical coupler 23. A light beam which is projected from the lens 7 and transmitted through the half-mirror 22 is detected by the beam profiler 4 to adjust the optical axis and while return light which is reflected by the half-mirror 22 to enter the optical fiber 2 again through the reverse path and is branched by the optical coupler 23 is detected by the power monitor 25, the focus of the lens is adjusted. The focus and optical axis of the lens can be adjusted at the same time (in the same state) to obtain efficiency. <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 a lens focus / optical axis adjusting method for adjusting a lens focus and an optical axis when assembling an optical component such as an optical fiber collimator in which a lens and an optical fiber are combined. Regarding the device.

[0002]

2. Description of the Related Art For example, in an optical fiber collimator in which an optical fiber and a lens are combined, the focus of the lens is adjusted (focusing) and the optical axis of the lens is adjusted (optical axis alignment).
Must be done correctly. FIG. 2 is a diagram for explaining a conventional lens adjusting method when assembling the optical fiber collimator 1, in which 2 is an optical fiber, 3 is a light source, and 4 is a beam profiler. The optical fiber collimator 1 includes a ferrule 5 attached to the tip of the optical fiber 2 in a case 6
The lens 7 is housed inside and facing the termination surface of the ferrule 5.
It is a configuration in which is arranged. FIG. 3 is a view for explaining another conventional lens adjusting method, in which a master optical fiber collimator 11 that has been properly focus-adjusted and optical-axis-adjusted is arranged to face the optical fiber collimator 1 to be adjusted. A power monitor 13 is connected to the optical fiber 12 of the master optical fiber collimator 11. The power monitor 13 includes a light receiver 13a and a measuring unit 13b that measures the light intensity based on the output of the light receiver 13a. 2 and 3, the focus of the lens 7 is adjusted by moving the lens 7 as shown by the arrow (a) (changing the direction of the lens 7), and the optical axis of the lens 7 is adjusted by the arrow (b). As shown in FIG.

[0003]

When the lens is adjusted by using the beam profiler 4 when assembling the optical fiber collimator 1, the optical axis of the lens 7 is adjusted by emitting the light from the light source 3 and passing through the optical fiber 2. 7
While detecting the light beam condensed by the beam profiler 4, move the lens 7 as indicated by the arrow (a) (change the direction of the lens 7) so that the position of the light beam is at the correct position. The optical axis of the lens 7 can be adjusted.
However, it is difficult to adjust the focal position of the lens 7 by the beam profiler 4. Therefore, for the focus adjustment of the lens 7, a focus monitor is arranged in place of the beam profiler 3 and the light intensity of the light beam is detected by the power monitor to adjust the focus of the lens. It is efficient.

When the master optical fiber collimator 11 is used for lens adjustment in assembling the optical fiber collimator 1, the light beam emitted from the lens 7 of the optical fiber collimator 1 enters the master optical fiber collimator 11. The light is received by the light receiver 13a of the power monitor 13 through the optical fiber 12, and the light intensity is detected by the measuring unit 13b. Therefore, the optical axis of the lens 7 can be adjusted by moving the lens 7 as shown by the arrow (a) while detecting the light intensity with the power monitor 13.
The focus position of the lens 7 can be correctly adjusted by moving the lens 7 back and forth in the optical axis direction as indicated by the arrow (b). However, in this method, if the optical axis is largely deviated, the light source cannot be visually confirmed, so it is necessary to change the light source to visible light and then make adjustment, which is extremely complicated.

The present invention has been made in view of the above circumstances, and makes it possible to simultaneously perform focus adjustment and optical axis adjustment of a lens in an optical component such as an optical fiber collimator,
It is an object of the present invention to provide a focus / optical axis adjusting method and device for a lens capable of performing efficient focus adjustment and optical axis adjustment work.

[0006]

According to the invention of claim 1, which solves the above-mentioned problems, the focus adjustment and the optical axis of the lens in an optical component in which a lens is arranged adjacent to the end face of an optical fiber for guiding light from a light source. A method of performing adjustment, in which a half mirror is arranged in front of the lens, and the optical axis of the lens is adjusted by the light emitted from the lens and transmitted through the half mirror, and reflected by the half mirror into the optical fiber. It is characterized in that the focus of the lens is adjusted by the returning return light.

According to a second aspect of the present invention, there is provided a method of performing focus adjustment and optical axis adjustment of the lens in an optical component in which a lens is arranged adjacent to an end face of an optical fiber that guides light from a light source. A half mirror is arranged in front of the lens, and while adjusting the optical axis of the lens while detecting the light beam emitted from the lens and transmitted through the half mirror by a light beam detection device, the light beam is reflected by the half mirror and the optical fiber is routed in the opposite path. Return light returning to the inside is branched by an optical coupler provided in the middle of the optical fiber and detected by a light intensity detection device,
The feature is that the focus of the lens is adjusted.

A third aspect of the present invention is a lens focus / optical axis adjusting device for performing focus adjustment and optical axis adjustment of the lens in an optical component in which a lens is disposed adjacent to an end face of an optical fiber for guiding light from a light source. Between a light beam detecting device for detecting a light beam emitted from the lens, a half mirror arranged between the light beam detecting device and the lens, and between the light source and the lens of the optical fiber. And an optical intensity detection device that detects the optical intensity of the return light that has been emitted from the lens, reflected by the half mirror, returned to the inside of the optical fiber through the reverse path, and branched by the optical coupler. It is characterized by that.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of the present invention, and is a diagram for explaining a method of adjusting the focus and the optical axis of the lens of the optical fiber collimator 1 when assembling the optical fiber collimator 1. Is. In the figure, 2 is an optical fiber, 3 is a light source, and 4 is a beam profiler as a light beam detector. Optical fiber collimator 1
In the configuration, the ferrule 5 attached to the tip of the optical fiber 2 is housed in the case 6, and the lens 7 is arranged so as to face the end face of the ferrule 5. The termination surface of the ferrule 5 may be either right-angled or obliquely polished, but in the case of oblique polishing, the ferrule 5 is accommodated in the case 6 while being inclined.

When assembling the optical fiber collimator 1, when the focus and the optical axis of the lens 7 are adjusted, the beam profiler 4 is arranged in front of the optical fiber collimator 1 and the half mirror is provided between the lens 7 and the beam profiler 4. 22 is arranged. Further, an optical coupler 23 is provided in the middle of the optical fiber 2 connecting the light source 3 and the optical fiber collimator 1, and the branch optical fiber 24 connected to the branch port of the optical coupler 23 is connected to the power monitor 25. The power monitor 25 has a light receiver 25a connected to the branch optical fiber 24, and a measuring unit 25b that measures the light intensity based on the output of the light receiver 25a. The above light source 3,
Beam profiler 4, half mirror 22, optical coupler 2
3. The power monitor 25 constitutes a focus / optical axis adjusting device 21 for performing focus adjustment and optical axis adjustment of the lens of the optical fiber collimator 1.

Regarding the optical axis adjustment of the lens 7, the half mirror 22 is emitted from the lens 7 of the optical fiber collimator 1.
While detecting the light beam that has passed through the beam profiler 4, move the lens 7 as shown by the arrow (a) so that the position of the light beam is in the correct position (change the direction of the lens 7), Adjust the optical axis.

Regarding the focus adjustment of the lens 7, the lens 7
The return light that has been emitted from the laser beam and is reflected by the half mirror 22 and returned to the inside of the optical fiber 2 through the opposite path is branched to the branch optical fiber 24 in the optical coupler 23 and is received by the light receiver 25a.
The light intensity of the return light is detected by the measuring unit 25b based on the output. While detecting the light intensity of the return light, the lens 7 is moved back and forth in the direction of the optical axis as indicated by the arrow (b), and the focal position of the lens 7 is adjusted correctly.

As described above, in the method of the present invention, the focus adjustment and the optical axis adjustment can be performed simultaneously (in the same state), which is extremely simple and efficient.

In the above embodiment, the optical fiber collimator 1
Although the focus adjustment and the optical axis adjustment of the lens 7 in the above have been described, the present invention is not limited to this and can be applied, for example, when used as a simple light source device. It can be applied as a lens focus / optical axis adjustment method.

[0015]

According to the present invention, a half mirror is arranged between a lens and a light beam detector to adjust the focus and the optical axis of a lens when assembling an optical component such as an optical fiber collimator. The optical axis of the lens is adjusted by the light emitted from the lens and transmitted through the half mirror, and the focus is adjusted by the return light that is reflected by the half mirror and returns to the inside of the optical fiber through the lens. The optical axis can be adjusted at the same time (in the same state), and the work efficiency of lens adjustment is greatly improved.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a focus / optical axis adjusting method for a lens according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a conventional method of adjusting the optical axis position of a lens of an optical fiber collimator using a beam profiler.

FIG. 3 is a diagram for explaining another conventional method, and is a diagram for explaining a method of adjusting the optical axis position of the lens of the optical fiber collimator using the master optical fiber collimator.

[Explanation of symbols]

1 Optical fiber collimator (optical parts) 2 optical fiber 3 light sources 4 Beam profiler (light beam detector) 5 ferrules 6 cases 7 lenses 21 Lens focus / optical axis adjustment device 22 Half mirror 23 Optical coupler 24 branch optical fiber 25 Power monitor (light intensity detector) 25a light receiver 25b Measuring unit

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Koichi Katayose             1440 Rokuzaki, Sakura City, Chiba Prefecture Fujikura Sa Co., Ltd.             Inside the warehouse F term (reference) 2H037 AA01 BA03 BA12 CA37 DA18                       DA22

Claims (3)

[Claims] 1. A method of performing focus adjustment and optical axis adjustment of the lens in an optical component in which a lens is arranged adjacent to an end face of an optical fiber that guides light from a light source, wherein a half mirror is provided in front of the lens. With placement
The optical axis of the lens is adjusted by the light emitted from the lens and transmitted through the half mirror, and the focus of the lens is adjusted by the return light reflected by the half mirror and returned to the optical fiber. Focus / optical axis adjustment method. 2. A method of performing focus adjustment and optical axis adjustment of the lens in an optical component in which a lens is arranged adjacent to an end face of an optical fiber that guides light from a light source, wherein a half mirror is provided in front of the lens. With placement
The optical axis of the lens is adjusted while the light beam emitted from the lens and transmitted through the half mirror is detected by the light beam detection device, and the return light reflected by the half mirror and returned to the inside of the optical fiber in the opposite path is A method of adjusting the focus / optical axis of a lens in an optical component, wherein the focus of the lens is adjusted while being branched by an optical coupler provided on the way and detected by a light intensity detection device. 3. A focus / optical axis adjusting device for a lens, which adjusts the focus and the optical axis of the lens in an optical component in which the lens is arranged adjacent to an end face of an optical fiber for guiding light from a light source, A light beam detecting device for detecting a light beam emitted from a lens, a half mirror arranged between the light beam detecting device and the lens, and an optical coupler provided between the light source and the lens of the optical fiber. And a light intensity detection device that detects the light intensity of the return light that has exited the lens, is reflected by the half mirror, returns to the inside of the optical fiber in the opposite path, and is branched by the optical coupler. Focus / optical axis adjustment device for optical components.