JPH09265025A - Ld module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the adjustment working process of an axis direction and to perform an optimum adjustment without generating a twist in an optical fiber. SOLUTION: An LD holder assembly 4 is formed by fixing an LD element 2 in between LD holders 1 with a ring member 3 while striking the stem 2a of the element 2 against the inside of the LD holder 1 and the LD holder 1 and the ringe member 3 are fixed with adhesive. A lens holder assemly 8 is formed by fixing a condenser lens 6 at one end of a lens holder 5 and by fixing an optical fiber 7 at the other end of the lens holder 5. In the lens holder 5, a screw part to be srewed with the screw part of an adjustment member 9 is arranged on the fixing side of the condenser lens 6. The condenser lens 6 condenses the laser beam to be emitted from the LD element 2 on the connector 7a of the optical fiber 7, which transmits the optical signal condensed on the connector 7a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LD module, and more particularly, to an optical axis adjusting method for connecting a laser diode having a function of converting an electric signal to an optical signal to an optical fiber.

[0002]

2. Description of the Related Art Conventionally, in this type of optical axis adjusting method, as shown in FIG. 4, a plurality of spacers 33 are provided between an LD (laser diode) element 31 and an LD holder 32.
By inserting a and 33b in combination, the distance between the LD element 31 and the spherical lens 36 is adjusted so that the optical output from the LD element 31 is maximized (hereinafter referred to as the adjustment in the optical axis direction). .

When the adjustment in the optical axis direction is completed, the ring member 34 is screwed into the LD holder 32, so that the LD element 3
1 is sandwiched and fixed between the LD holder 32 and the ring member 34.

Further, after fixing the LD element 31 to the LD holder 32, the LD element 31 is placed in a plane perpendicular to the optical axis of the LD element 31 so that the light output from the LD element 31 is maximized.
The fixing position of the holder 32 and the lens holder 35 is adjusted. When the adjustment of the fixed position is completed, the LD holder 32 and the lens holder 35 are welded with a YAG laser beam.

Here, the selection of the plurality of spacers 33a and 33b is performed by the following method. First, LD in the LD holder 32
The ring member 3 is inserted after the LD element 31 is inserted.
4 is screwed into the LD holder 32 to be in a temporarily assembled state.
In this state, the distance from the end surface of the LD holder 32 to the LD chip 31a of the LD element 31 is measured by a distance measuring device.

The value obtained by subtracting this measured value from the actual optical distance from the LD chip 31a to the spherical lens 36 is the combined thickness dimension of the plurality of spacers 33a and 33b. A plurality of spacers 33a, so that the combined thickness dimension is obtained.
33b is selected and inserted between the LD element 31 and the LD holder 32.

On the other hand, in the exit beam optical unit for the scanner, as shown in FIG. 5, the threaded portion 44a of the lens frame 44 to which the lens 43 is fixed is attached to the threaded portion 42a of the bar body 42 to which the LD element 41 is fixed. The optical distance between the LD element 41 and the lens 43 is adjusted by screwing and rotating the lens frame 44.

In this case, a spring 45 is arranged between the bar body 42 and the lens frame 44, and the lens frame 44 is biased by the spring 45 in the direction away from the LD element 41, whereby the screw portion 42a is formed. The spring 45 absorbs the rattling between the screw portion 44a and the screw portion 44a.

When the adjustment of the optical distance between the LD element 41 and the lens 43 is completed by rotating the lens frame 44,
The lens frame 44 is fixed to the bar body 42 by injecting the adhesive 47 through the through hole 46 provided in the bar body 42.

A method for adjusting the optical axis in the above-mentioned output beam optical unit for scanner is described in Japanese Patent Laid-Open No. 5-1217.
No. 82 publication.

[0011]

In the above-mentioned conventional optical axis adjusting method, in the case of a method of inserting a plurality of spacers in combination between the LD element and the LD holder, the adjustment in the optical axis direction is finally performed. The spacer is adjusted step by step in the minimum thickness unit, and it is not always possible to adjust to the optimum position where the optical output is maximum, and the adjustment is difficult.

Further, since steps such as spacer selection are required, workability is deteriorated and a large number of man-hours are required for adjustment. Furthermore, a plurality of types of spacers are required to improve the efficiency of the adjustment.

On the other hand, in the case of the method of adjusting the optical distance between the LD element and the lens by rotating the lens frame to which the lens is fixed, since the laser beam for scanning is emitted, it passes through the lens. The laser beam is applied to a polygon mirror or the like. In other words, nothing is mounted on the lens frame other than the lens.

However, if this method is applied to an LD module used for optical communication, an optical fiber is attached to the lens frame, and the lens frame is rotated when adjusting the optical distance between the LD element and the lens. The optical fiber is twisted, and the optical fiber is loaded.

Therefore, an object of the present invention is to solve the above-mentioned problems, and to reduce the work steps for adjusting the optical axis direction and to perform the optimum adjustment without causing the optical fiber to be twisted. To provide.

[0016]

An LD module according to the present invention includes a laser diode element having a function of converting an electric signal into an optical signal, a holder member for holding the laser diode element at a preset position, and An optical fiber for transmitting an optical signal from a laser diode element, a condenser lens for condensing an optical signal emitted from the laser diode element at the tip of the optical fiber, and an optical fiber for holding the optical fiber at one end and at the other end. A lens holder member that holds the condensing lens, and the other end surface that is screwed from one end surface side to a screw portion provided on the outer periphery of the lens holder member and that opposes the one end surface is the optical signal of the holder member. An adjusting member fixed to the emitting surface side of the laser diode element and rotating the adjusting member to adjust the distance between the laser diode element and the condenser lens. The adjusting member has to be secured to the holder member.

In addition to the above structure, another LD module according to the present invention has a structure in which the laser diode element is sandwiched between the holder member and the screw member provided on the inner circumference of the holder member. It has a ring member.

In another LD module according to the present invention, in addition to the above structure, at least one of the threaded portion on the outer circumference of the lens holder member and the threaded portion on the inner circumference of the adjusting member is coated with the adjusting member. Is provided on the lens holder member, and the adhesive is cured after the distance between the laser diode element and the condenser lens is adjusted.

In still another LD module according to the present invention, in the above structure, the holder member and the adjusting member are welded after the fixing positions of the holder member and the adjusting member are adjusted on their contact surfaces. I try to fix it.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the operation of the present invention will be described below.

L having a function of converting an electric signal into an optical signal
An LD holder for holding the D element at a preset position,
Arranged on the outer periphery of a lens holder that holds an optical fiber that transmits an optical signal from an LD element at one end and a condenser lens that condenses the optical signal emitted from the LD element at the tip of the optical fiber at the other end. An adjusting member that is screwed into the screw part
The adjustment member is rotated to adjust the distance between the LD element and the condenser lens, and then fixed.

This prevents the optical fiber from being twisted. Further, since the adjustment of the optical axis direction is performed by screwing the lens holder and the adjusting member, the adjustment by the conventional spacer is not necessary, and the smooth adjustment can be performed instead of the stepwise adjustment by the spacer. It is possible to reduce the work process of axial adjustment and perform optimum adjustment.

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of one embodiment of the present invention. In the figure, an LD (laser diode) holder assembly 4 according to an embodiment of the present invention abuts a stem 2a of an LD element 2 on a bottom surface A of a recess in the LD holder 1, and then a ring member 3 is recessed in the LD holder 1. The LD element 2 is fixedly formed between the LD holder 1 and the ring member 3 by being screwed into.

An adhesive is applied in advance to the threaded portion provided on the outer periphery of the ring member 3 before being screwed into the recess in the LD holder 1, so that the LD element 2 is connected to the LD holder 1 and the ring member 3. After being fixed between the two, the adhesive is cured by heat or the like.

The lens holder assembly 8 is formed by fixing the condenser lens 6 to one end of the lens holder 5 and fixing the optical fiber 7 to the other end of the lens holder 5. Here, the lens holder 5 is provided with a screw portion that is screwed into the screw portion of the adjusting member 9 on the fixed side of the condenser lens 6.

The condenser lens 6 is for condensing the laser beam emitted from the LD element 2 on the connector 7a of the optical fiber 7, and the optical fiber 7 transmits the optical signal condensed on the connector 7a. It is for.

FIG. 2 is a diagram showing an LD module assembling method according to an embodiment of the present invention, and FIG. 3 is a block diagram showing a configuration of an LD module assembling apparatus according to an embodiment of the present invention.

An LD module assembling apparatus according to an embodiment of the present invention comprises an optical axis adjusting device 20, an optical power meter 21 connected to the optical axis adjusting device 20 through an optical fiber 7, and a power source for the optical axis adjusting device 20. It is composed of a power supply 22 to be supplied.

This optical axis adjuster 20 is an LD holder assembly 4
Is electrically connected to the chuck arm 10 for fixing the LD holder 1, the chuck arm 11 for fixing the lens holder 5 of the lens holder assembly 8, the pressure arms 12, 13 and the lead terminal 2b of the LD element 2. And a socket 14.

The process of assembling the LD module according to the embodiment of the present invention will be described with reference to FIGS. When assembling the LD module, first, the stem 2a of the LD element 2 is butted against the bottom surface A of the recess in the LD holder 1, and then the ring member 3 is screwed into the recess in the LD holder 1 to LD the LD element 2 The LD holder assembly 4 is formed by fixing between the holder 1 and the ring member 3, and curing the adhesive applied to the threaded portion of the ring member 3 by heat or the like.

The LD holder 1 of this LD holder assembly 4 is fixed by the chuck arm 10 of the optical axis adjuster 20, and the LD
Connect the lead terminal 2b of the element 2 to the socket 1 of the optical axis adjuster 20.
4 to electrically drive the LD element 2.

Then, the threaded portion of the lens holder 5 of the lens holder assembly 8 is screwed into the threaded portion of the adjusting member 9 to temporarily tighten it, and the LD holder assembly 4 is placed on the end surface of the LD holder 1. At this time, the lens holder 5 of the lens holder assembly 8
Is fixed by the chuck arm 11, and the optical fiber 7 is connected to the optical power meter 21.

After that, power is supplied from the power supply 22 to the optical axis adjuster 20 to drive the LD element 2, and the optical power meter 2
The adjustment member 9 is rotated while the optical output from the LD element 2 is monitored at 1 to adjust the optical axis direction.

In this case, since the lens holder 5 is only vertically moved by the rotation of the adjusting member 9, the optical fiber 7 is not twisted. Further, when the optical output from the LD element 2 displayed on the optical power meter 21 becomes maximum due to the adjustment of the optical axis direction by the rotation of the adjusting member 9, the adhesive agent previously applied to the lens holder 5 The lens holder 5 is cured by heat.
And the adjusting member 9 are fixed.

After the adjustment of the optical axis direction is completed, an indication is displayed on the optical power meter 21 in order to adjust the fixed position of the LD holder 1 and the lens holder 5 in a plane perpendicular to the optical axis of the LD element 2. The chuck arm 11 is moved on a plane perpendicular to the optical axis of the LD element 2 until the light output from the LD element 2 is maximized.

When the adjustment of the fixed positions of the LD holder 1 and the lens holder 5 is completed, the pressure arms 12 and 13 press the end surface C of the adjusting member 9, and the YAG laser is pressed while pressing the adjusting member 9 against the LD holder 1. The LD holder 1 is welded to the adjusting member 9 with a beam (not shown).

As described above, the LD holder 1 for holding the LD element 2 having the function of converting an electric signal into an optical signal at a preset position, and the optical fiber 7 for transmitting the optical signal from the LD element 2 at one end thereof. For adjusting the optical signal emitted from the LD element 2 to the other end of the lens holder 5 for holding the condenser lens 6 for condensing the optical signal at the tip of the optical fiber 7. By rotating the adjusting member 9 to adjust the distance between the LD element 2 and the condenser lens 6 and then fixing the member 9, the optical fiber 7 is prevented from being twisted.

Further, since the adjustment of the optical axis direction is performed by screwing the lens holder 5 and the adjusting member 9, the conventional adjustment by the spacer becomes unnecessary, and smooth adjustment which is not stepwise adjustment by the spacer is possible. Therefore,
It is possible to reduce the work process of adjustment in the optical axis direction and perform optimum adjustment.

[0039]

As described above, according to the present invention, a holder member for holding a laser diode element having a function of converting an electric signal into an optical signal at a preset position, and one end of the holder member from the laser diode element To the threaded portion arranged on the outer periphery of the lens holder member that holds the optical fiber that transmits the optical signal and that also holds the condenser lens that collects the optical signal emitted from the laser diode element at the tip of the optical fiber at the other end. The adjusting member to be screwed is fixed by adjusting the distance between the laser diode element and the condensing lens by rotating the adjusting member, so that the optical fiber is not twisted in the optical axis direction. There is an effect that the number of adjustment work steps can be reduced and optimum adjustment can be performed.

[Brief description of drawings]

FIG. 1 is a sectional view of one embodiment of the present invention.

FIG. 2 is a diagram showing an LD module assembling method according to an embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of an LD module assembling apparatus according to an embodiment of the present invention.

FIG. 4 is a sectional view of a conventional example.

FIG. 5 is a sectional view of a conventional example.

[Explanation of symbols]

 1 LD Holder 2 LD Element 2a Stem 2b Lead Terminal 3 Ring Member 4 LD Holder Assembly 5 Lens Holder 6 Condensing Lens 7 Optical Fiber 7a Connector 8 Lens Holder Assembly 9 Adjusting Member 11, 10 Chuck Arm 12, 13 Pressure Arm 14 Socket 20 Optical axis adjuster 21 Optical power meter 22 Power supply

Claims (4)

[Claims] 1. A laser diode element having a function of converting an electric signal into an optical signal, a holder member for holding the laser diode element at a preset position, and a light transmitting an optical signal from the laser diode element. A fiber, a condenser lens that condenses an optical signal emitted from the laser diode element at the tip of the optical fiber, and a lens holder member that holds the optical fiber at one end and the condenser lens at the other end. An adjusting member screwed from one end face side to a threaded portion provided on the outer periphery of the lens holder member and having the other end face facing the one end face fixed to the optical signal emission face side of the holder member; And adjusting the distance between the laser diode element and the condenser lens by rotating the adjusting member, and then fixing the adjusting member to the holder member. LD module characterized by the above. 2. A ring member which is screwed into a threaded portion provided on the inner circumference of the holder member to hold the laser diode element between the holder member and the holder member. LD module. 3. An adhesive which is applied to at least one of a threaded portion on the outer circumference of the lens holder member and a threaded portion on the inner circumference of the adjustment member, and which includes an adhesive for adhering the adjustment member to the lens holder member, The LD module according to claim 1 or 2, wherein the adhesive is cured after adjusting the distance between the laser diode element and the condenser lens. 4. The holder member and the adjusting member are fixed by welding after adjusting the fixing positions of the holder member and the adjusting member on their contact surfaces. The LD module according to any one of claims 1 to 3.