WO2002039154A1

WO2002039154A1 - Semiconductor laser module, and raman amplifier using the semiconductor laser module

Info

Publication number: WO2002039154A1
Application number: PCT/JP2001/009741
Authority: WO
Inventors: Yuichiro Irie; Jun Miyokawa; Takeshi Aikiyo
Original assignee: The Furukawa Electric Co.,Ltd.
Priority date: 2000-11-07
Filing date: 2001-11-07
Publication date: 2002-05-16
Also published as: JP2002148489A

Abstract

A semiconductor laser module with high output, less noise, excellent stability of wavelength, and high reliability independent of a variation in working environment temperature, wherein a thermo module (25) having a base side plate material (17), a bottom plate side plate material (18), and Peltier elements (19) is disposed on the bottom plate (26) of a package (27), a base (2) is disposed on the thermo module (25), and a laser diode (1), a first optical fiber (4) allowing the laser beam radiated from the laser diode (1) to return to the laser diode (1), and fixing members (6, 7) for supporting the first optical fiber (4) at at least two longitudinal positions are disposed on the base (2), the base (2) is formed of a laser diode mounting member (8) on the thermo module (25) and a fixing member mounting member (5) installed thereon, and the laser diode mounting member (8) is formed of a material having a coefficient of linear expansion between the coefficient of linear expansion of the fixing member mounting member (5) and that of the base side plate material (17) of the thermo module (25).

Description

Description Semiconductor laser module and Raman amplifier using the semiconductor laser module

The present invention relates to a semiconductor laser module used in the optical communication field and a Raman amplifier using the semiconductor laser module. Background art

With the development of the information society, the amount of communication information tends to increase dramatically. With the increase of such information, wavelength multiplex transmission (WDM transmission) has been widely accepted in the communication field, and the era of wavelength multiplex transmission is now approaching. Wavelength-multiplexed optical transmission can transmit light of multiple wavelengths over a single optical fiber. Therefore, it is an optical transmission method suitable for large-capacity high-speed communication. Currently, studies on this transmission technology are being actively conducted.

Up to now, it has been studied to perform wavelength multiplex transmission in the 1.55-μm wavelength band, which is the gain band of an erbium-doped fiber (EDF) type optical amplifier. In recent years, expectations for Raman amplification have been increasing in order to make the bandwidth of wavelength multiplexing transmission even wider.

Raman amplification uses the phenomenon that when strong light (cocoon-induced light) is incident on an optical fiber, gain appears about 100 nm longer than the excitation light wavelength due to induced Raman scattering. In other words, Raman amplification is an optical signal amplification method that utilizes the phenomenon that when signal light in the wavelength region having the above gain is incident on an optical fiber that has been pumped with pump light, the signal light is amplified. is there. Therefore, existing optical fibers can be used as an amplification medium in Raman amplification without using EDF as an amplification medium. In addition, an amplification gain can be obtained at an arbitrary wavelength. Therefore, the number of signal light channels in wavelength division multiplexing transmission can be increased by using Raman amplification.

However, the Raman gain is as small as about 3 dB with a 100 mW pump light input when using a (normally existing) communication optical fiber. For this reason, it is necessary to provide a plurality of excitation light sources (pump lasers) and obtain a strong excitation light by multiplexing these. In general, it has been studied to achieve a total excitation light intensity of about 500 mW to 1 W by multiplexing.

Also, in Raman amplification (especially forward pumping), the process of amplification occurs quickly, so if the pump light intensity fluctuates, the Raman gain fluctuates. For this reason, the fluctuation of the Raman gain appears directly as the fluctuation of the signal light intensity. Therefore, when performing Raman amplification, it is important to reduce the noise of the pump light.

In view of the above, in order to apply Raman amplification to wavelength division multiplexing transmission, the pump light source of the Raman amplifier must have low noise, high output of, for example, 300 mW or more, and It is necessary to provide a light source with good stability. The development of a semiconductor laser module having such characteristics for a pumping light source is very important.

Incidentally, a semiconductor laser module is a device in which laser light from a semiconductor laser (laser diode) is optically coupled to an optical fiber on the optical transmission side. It is applied not only as an excitation light source as described above but also as a signal light source, and various configurations have been proposed. Disclosure of the invention The present invention provides a semiconductor laser module applicable to a signal light source or an excitation light source, and a Raman amplifier using the semiconductor laser module. A semiconductor laser module according to one aspect of the present invention is configured as follows:

Base;

A laser diode mounted on the base; a first optical fiber mounted on the base and optically coupled to the laser diode;

A plurality of fixing members mounted on the base and arranged at intervals in the longitudinal direction of the first optical fiber;

A second optical fiber disposed opposite to the other end of the laser diode to receive and transmit light emitted from the other end of the laser diode, wherein the first optical fiber has It is located toward one end of the laser diode,

The first optical fiber has a diffraction grating that reflects light having a set wavelength, and is configured to return the light having the set wavelength among the lights emitted from one end of the laser diode to the laser diode. And

The first optical fiber is fixed to the base by a fixing member at a plurality of positions at intervals in the longitudinal direction of the optical fiber.

A semiconductor laser module according to another aspect of the present invention is configured as follows;

Knockage;

A base housed in the package;

A laser diode mounted on the base; a laser diode mounted on the base; A first optical fiber disposed toward one end of the diode and optically coupled to the laser diode;

A fixing member mounted on the base, for fixing the first optical fiber to the base;

A second optical fiber disposed opposite to the other end of the laser diode, for receiving and transmitting light emitted from the other end of the laser diode;

A thermocouple mounted on the bottom plate of the package and mounting the base;

Here, the first optical fiber has a diffraction grating that reflects light of a set wavelength, and returns the light of the set wavelength among the lights emitted from one end side of the laser diode to the laser diode. The thermo module comprises: a base side plate on which the base is mounted; a bottom plate side plate placed on the bottom plate of the package; and a Peltier element sandwiched and fixed between these plate members. ,

A laser diode mounting member that is mounted and fixed in contact with an upper surface of the thermo module and mounts the laser diode; a fixing member that is coupled to the laser diode mounting member and mounts the fixing member; And a mounting member.

The laser diode mounting member is formed of a material having a linear expansion coefficient in a range between a linear expansion coefficient of the fixed member mounting member and a linear expansion coefficient of a base side plate of the thermomodule.

A semiconductor laser module according to still another embodiment of the present invention is configured as follows:

Package;

A base housed in the package; A laser diode mounted on the base;

A first optical fiber mounted on the base, arranged with the fiber tip side toward one end of the laser diode, and optically coupled to the laser diode;

Here, the first optical fiber has a diffraction grating that reflects light of a set wavelength, and returns the light of the set wavelength among the lights emitted from one end side of the laser diode to the laser diode. A laser diode mounting member for mounting and fixing the laser diode in contact with an upper surface of the thermo module; and a base coupled to the laser diode mounting member for fixing the base. And a fixed member mounting member for mounting the member.

The bottom plate of the package is formed of a material having substantially the same linear expansion coefficient as the laser diode tower mounting member of the base.

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A base housed in the package;

A fixing member mounted on the base and fixing the first optical fiber to the base while holding the first optical fiber from both sides;

A thermoelectric unit mounted on the base plate of the package and mounting the base;

Here, the first optical fiber has a diffraction grating that reflects light of a set wavelength, and the light of the set wavelength among the lights emitted from one end of the laser diode is transmitted to the laser diode. The base is provided with a fixed member tower mounting portion for mounting the fixed member on the base.

The fixing member mounting portion and the fixing member are laser-welded at a first laser welding portion.

The first optical fiber side and the fixing member are laser-welded at a second laser-welded portion,

The first laser welded portion and the second laser welded portion are substantially the same height in a direction perpendicular to the package bottom plate. The semiconductor laser module according to still another embodiment of the present invention. Is composed as follows:

Base;

A laser diode mounted on the base; a laser die mounted on the base; A first optical fiber disposed toward one end of the diode and optically coupled to the laser diode;

A thermo module on which the base is mounted; wherein the first optical fiber has a diffraction grating that reflects light having a set wavelength, and the first optical fiber is set out of light emitted from one end of the laser diode. A wavelength of light is fed back to the laser diode, and at least a part of the base is located at one or both sides of the side of the first optical fiber, and the length of the first optical fiber is Along the direction

A bending preventing means for preventing bending of the base is provided.

Base;

A laser diode mounted on the base; a first optical fiber mounted on the base, arranged with a fiber tip end side toward one end of the laser diode, and optically coupled to the laser diode;

A fixing member mounted on the base and fixing the first optical fiber to the base at a position near the laser diode and at a position farther from the laser diode than the laser diode;

A second optical fiber disposed opposite to the other end of the laser diode, for receiving and transmitting light emitted from the other end of the laser diode; Iva;

A thermo module on which the base is mounted; wherein the first optical fiber has a diffraction grating that reflects light having a set wavelength, and the first optical fiber is set out of light emitted from one end of the laser diode. Wavelength of light is fed back to the laser diode, wherein the first optical fiber and the laser diode are aligned, and the first optical fiber is on a side closer to the laser diode. Are fixed from both sides by fixing members at each point on the far side

The fixing member for fixing the position far from the laser diode comprises a pair of fixing parts.

The fixed parts of this pair are fixed to the base with the first optical fiber sandwiched from both sides,

The fixed parts and the first optical fiber side are fixed by laser welding. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a configuration explanatory view showing a first embodiment of a semiconductor laser module according to the present invention, and FIG. 2 is a plan view showing a configuration of a peripheral portion of a base of the semiconductor laser module of the first embodiment. FIG. 3 is an exploded view showing the structure of the base in the first embodiment in an exploded view. FIG. 4 is a sectional view taken along line AA of FIG. 3, and FIGS. FIG. B is an explanatory diagram showing a perspective configuration of each fixing member provided in the first embodiment.

FIG. 6 is an explanatory view showing a fiber lens of the first optical fiber provided in the first embodiment and its peripheral configuration, and FIG. 7 is a laser diode in the first embodiment. Perspective view showing the arrangement area of FIG. 8 is an explanatory diagram showing a simplified cross-sectional configuration on the side where the second optical fiber is disposed in the first embodiment, and FIG. 9 is a diagram showing a semiconductor laser module according to the present invention. FIG. 10 is a perspective view showing the configuration of the second embodiment with a package partially omitted. FIG. 10 shows a laser diode and a first optical fiber in a third embodiment of the semiconductor laser module according to the present invention. FIG. 11 is a perspective view showing the fixing configuration of FIG. 11, and FIG. 11 is a plan view of FIG.

FIG. 12 is an exploded view showing the structure of the base in the third embodiment in an exploded view. FIG. 13 is a diagram showing the structure around the base in another embodiment of the semiconductor laser module according to the present invention. FIG. 14 is an explanatory view of a fiber lens structure of a first optical fiber in another embodiment of the semiconductor laser module according to the present invention. FIG. 15 is a perspective view of the semiconductor laser module according to the present invention. FIG. 16 is an explanatory view of a second optical fiber in another embodiment of the semiconductor laser module. FIG. 16 is an explanatory view showing an example of a conventional semiconductor laser module in a cross section. FIG. A is a diagram showing a configuration of the Peltier device, and FIG. 17B is an explanatory diagram showing a problem of the semiconductor laser module. BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described in more detail with reference to the accompanying drawings. Prior to describing the embodiments of the present invention, for convenience of description, first, a conventional example will be described. FIG. 16 shows an example of a conventional semiconductor laser module. This semiconductor laser module is for a signal light source, and employs fiber grating technology to improve the wavelength stability.

This conventional semiconductor laser module has been proposed in a Japanese Patent Application Publication No. (publication number: 2000-2008). 1st 6 In the figure, a thermomodule 25 is provided in a knockout 27. The base 2 is mounted on the thermo module 25. The laser diode 1 is mounted and fixed on the LD bonding portion 2 1 of the base 2 via the heat sink 22.

On the base 2, a first optical fiber 4 optically coupled to the laser diode 1 is mounted. The first optical fiber 4 is disposed with the distal end of the fiber lens 14 formed on the distal end thereof facing the one end 31 of the laser diode 1. The first optical fiber 4 is housed in a metal sleep 3. The first optical fiber 4 is fixed by laser welding to a fixed arm 63 projecting above the base 2 at a fixed portion 62.

Since the sleeve 3 and the base 2 are fixed by laser welding, the base 2 is preferably formed of a metal having low thermal conductivity and high laser weldability. In addition, since the first optical fiber 4 is mounted on the base 2, the material of the base 2 is preferably a material having a linear expansion coefficient close to that of the glass-based material forming the first optical fiber 4. . Therefore, in a conventional semiconductor laser module, the base 2 is generally formed of a Fe—Ni—Co alloy known as Copal (trademark).

The first optical fiber 4 has a grating 12 as a diffraction grating that reflects light of a set wavelength. The first optical fiber 4 receives light emitted from one end 31 of the laser diode 1 via a fiber lens 14. Then, of the received light, the light of the set wavelength is reflected and returned to the laser diode 1.

Further, at the rear end side of the first optical fiber 4, a monitoring diode 9 is disposed to face. The monitor photodiode 9 is fixed to the monitor photodiode fixed part 39. The monitor photodiode fixing section 39 is fixedly arranged in the package 27. Monitor Photodiode 9 Monitors the output of the laser diode 1 by receiving the laser light transmitted through the first optical fiber 4.

On the other end 30 side of the laser diode 1, a second optical fiber 13 is arranged to face the other via a space. The second optical fiber 13 receives the light emitted from the other end 30 of the laser diode 1 and transmits it. The connection end face of the second optical fiber 13 is fixedly inserted into a ferrule 59, and the ferrule 59 is fixed to the rear end of the package 27.

Between the other end 30 of the laser diode 1 and the second optical fiber 13, a collimating lens 51, a light transmitting plate 55, and a condensing lens 57 are spaced from each other in this order from the laser diode 1 side. It is arranged. The collimator lens 51 is fixed to the base 2. The condenser lens 57 is fixed to the lens holder 56 and is fixed to the package 27.

In such a conventional semiconductor laser module, the thermomodule 25 is usually mounted on the bottom plate 26 of the package 27. The bottom plate 26 of the package 27 is made of Cu—W alloy Cu W 20 (weight ratio of Cu is 20% and W is 80%). In addition, as shown in FIG. 17A, the thermo module 25 usually includes a base plate 17, a bottom plate 18, and a Peltier element 1 sandwiched and fixed between the plates 17, 18. 9 Is formed by both the base side扳材1 7 and the bottom plate side plate member 1 8 of the thermo-module 2 5 A 1 ₂ O _3.

In the semiconductor laser module, the first optical fiber 4 and the second optical fiber 13 are both centered on the laser diode 1. Then, the laser light emitted from one end 31 of the laser diode 1 is received by the first optical fiber 4. The light having the set wavelength is reflected from the grating 12 and returns to the laser diode 1, and is emitted from the other end 30 of the laser diode 1. This output light is transmitted to the second optical fiber 13. Thus, the light is received, transmitted through the second optical fiber 13, and provided for a desired use.

As described above, when the laser light is oscillated while returning the set wavelength light of the laser light emitted from one end 31 of the laser diode 1 to the laser diode 1, the first optical fiber The distance between the tip of 4 and the laser diode 1 can be reduced. For this reason, it is possible to widen the frequency range in which the semiconductor laser module has a good RIN (Relative Inte nite n Si ty N o i s e) characteristic.

Also, in a semiconductor laser module, when a current is applied to drive the laser diode 1, the temperature of the laser diode 1 rises due to heat generation. This temperature rise causes a change in the oscillation wavelength and light output of the laser diode 1. For this reason, when using the semiconductor laser module, the temperature of the laser diode 1 is measured by a thermistor (not shown) fixed near the laser diode 1. Based on the measured value, the current flowing through the thermo module 25 is controlled to control the temperature of the laser diode 1 to be constant.

As described above, the semiconductor laser module having the above configuration receives the light emitted from the laser diode 1 by the first optical fiber 4, and reflects the light having a set wavelength out of the light by the grating 12. It is a configuration to return to the code 1. Therefore, when the first optical fiber 4 is displaced with respect to the laser diode 1, the optical coupling efficiency between the laser diode 1 and the first optical fiber 4 is greatly reduced.

The above-described conventional semiconductor laser module has a configuration in which the first optical fiber 4 is sandwiched and fixed by the fixing portion 62 at one position in the longitudinal direction. Therefore, it is difficult to properly center and fix the first optical fiber 4. Therefore, when fixing the first optical fiber 4, There has been a problem that displacement is likely to occur.

Further, the above good Una conventional semiconductor laser module, usually, the base 2 is formed by copal, the base side plate member 1 7 of thermo-module is formed by A 1 ₂ O _3. In this configuration, the base 2 and the base side plate 17 have significantly different linear expansion coefficients. Then, the base 2 bends as shown in FIG. 17B with the operation of the thermo module 25 when the semiconductor laser module is used. This bending causes a problem that the laser diode 1 and the first optical fiber 4 are displaced from the centering position, and the optical coupling efficiency between the laser diode 1 and the first optical fiber 4 is reduced. Was.

Also, for example, when the semiconductor laser module is left in a high temperature environment of 75 to 85 ° C without using the semiconductor laser module, the linear expansion coefficient between the base 2 and the base side plate 17 of the thermomodule 25 also increases. The difference also causes base 2 to bow. As a result, the optical coupling between the laser diode 1 and the first optical fiber 4 is deviated, and when the semiconductor laser module is used, the optical coupling does not completely return to the original state, and the optical coupling shift remains. turn into.

In particular, in the conventional semiconductor laser module, the fixing portion 62 of the sleeve 3 is on the tip side of the fixing arm 63 formed to protrude above the base 2. That is, since the fixed portion 62 is formed at a position higher than the bottom of the base 2, the sleeve 3 is largely displaced when the base 2 is bent. As a result, the rate of decrease in the optical coupling efficiency between the laser diode 1 and the first optical fiber 4 was large.

Then, as described above, when the optical coupling efficiency between the laser diode 1 and the first optical fiber 4 decreases in accordance with a change in the use environment temperature when the semiconductor laser module is used and when it is left unattended, the first optical fiber 4 The intensity of the light received and returned to the laser diode 1 decreases. When the intensity of the return light decreases, the light with high output and stable wavelength from the semiconductor laser module Output and transmission.

Therefore, if the configuration of the above-described conventional semiconductor laser module is applied to, for example, a signal light source or a pump light source for Raman amplification, a required output having a stable wavelength cannot be obtained. This makes it difficult to construct a wavelength division multiplexing transmission system.

One aspect of the present invention is to optically couple a laser diode and an optical fiber that receives laser light from the laser diode and returns light of a set wavelength to the laser diode with high accuracy regardless of a temperature change. A highly reliable semiconductor laser module is provided. In another aspect, the present invention provides a pumping light source having low noise, high power, and good wavelength stability, which is suitable for wavelength multiplex transmission by using the semiconductor laser module as described above. Provide an amplifier.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description of the embodiments, the same reference numerals are given to the same parts as those in the conventional example, and the overlapping description is omitted or simplified. FIG. 1 is a perspective view showing the configuration of a first embodiment of the semiconductor laser module according to the present invention. The semiconductor laser module of this embodiment also has a package 27 for accommodating the laser diode 1 and the like as in the conventional example. In FIG. 1, the package 27 is shown in a partially omitted state.

As shown in FIG. 1, the semiconductor laser module of the first embodiment includes a thermo module 25, a base 2, a laser diode 1, a first optical fiber 4, and the like provided in a package 27. It is configured. A plurality of lead terminals 60 are arranged on the side wall of the package 27 with a space therebetween, and the lead terminals 60 are formed so as to protrude toward the outside of the package 27.

The first embodiment is different from the conventional example in the configuration of the base 2 and the first optical fiber. „Ha _{/ ra}

PCT / JP01 / 09741

15 In this configuration, the eyepiece 4 is fixed to the base 2. With a configuration different from these conventional examples, the semiconductor laser module of the first embodiment has a reliable optical coupling between the laser diode 1 and the first optical fiber 4 with high accuracy irrespective of changes in the use environment temperature. It is a semiconductor laser module with high performance. In the first embodiment, the base 2 on which the laser diode 1 is directly or indirectly mounted is a laser diode mounting member 8 on which the laser diode 1 is mounted, and a fixing member mounting member provided on the laser diode mounting member 8. 5 and. The fixing member mounting member 5 mounts the fixing members 6 and 7, and the fixing members 6 and 7 are arranged at an interval in the longitudinal direction of the optical fiber.

The first optical fiber 4 is fixed through a metal sleeve 3 as an optical fiber holding member. The fixing members 6 and 7 fix the first optical fiber 4 to the base 2 by supporting and fixing the sleep 3. The same grating as that shown in FIG. 16 is formed in the core of the first optical fiber 4.

In the first embodiment, as described above, the first optical fiber 4 is fixed to the base 2 by the fixing members 6 and 7 at a plurality of points (here, two points) spaced apart in the longitudinal direction of the optical fiber. ing. The first optical fiber 4 is clamped and fixed from both sides by fixing members 6 and 7 in a state where the first optical fiber 4 is aligned with the laser diode 1.

Base 2 is mounted on thermo module 25. The laser diode mounting member 8 of the base 2 is arranged in contact with the thermo module 25. Also, as shown in FIGS. 1 and 3, an LD bonding portion 21 which is formed integrally with the laser diode mounting member 8 is provided above the laser diode mounting member 8. The LD bonding part 21 is a laser diode mounting area. Fixing member mounting member 5 The laser diode mounting member 8 is arranged at a position avoiding the laser diode mounting area of the laser diode mounting member 8.

FIG. 3 is a perspective view showing the base 2 in an exploded state, and the fixing member mounting member 5 is mounted on the laser diode mounting member 8 at the position of the silver mouth ゥ joint 46 shown by hatching in FIG. Is connected and fixed.

As described above, the base 2 is configured to include the fixing member mounting member 5 and the laser diode mounting member 8. The laser diode mounting member 8 is made of a material having a linear expansion coefficient in a range between the linear expansion coefficient of the fixed member mounting member 5 and the linear expansion coefficient of the base side plate 17 of the thermomodule 25. It is formed by. Specifically, in the first embodiment, the fixing member mounting member 5 is formed of copearl, and the laser diode mounting member 8 is a Cu—W alloy CuWIO (weight ratio of Cu is 10%, W 90%).

CuW10 has a thermal conductivity of 180 to 200 (W / mK), which is about 17 to 18 (W / m-K), which is the thermal conductivity of Copal. It has 10 times the thermal conductivity.

In the first embodiment, the bottom plate 26 of the package 27 is formed of the same material as the laser diode mounting member 8 of the base 2. Thereby, the linear expansion coefficient of the bottom plate 26 and the linear expansion coefficient of the laser diode mounting member 8 are made the same.

As shown in FIGS. 1 and 2, the fixing member mounting member 5 as the fixing member mounting portion and the fixing members 6 and 7 are laser-welded at a first laser welded portion 10. The fixing members 6, 7 and the sleeve 3 are laser-welded at a second laser-welded portion 11 (11a, lib). The height of the first laser welded portion 10 and the height of the second laser welded portion 11 in a direction perpendicular to the package bottom plate 26 are substantially the same. The laser welding is performed by a YAG laser or the like. The difference between the height of the first laser welded portion 10 and the height of the second laser welded portion 11 in the direction perpendicular to the package bottom plate 26 is within ± 500 mm, preferably within ± 50 μπι. I have to.

The height of the laser welded portions 10 and 11 in FIG. 12 on the fixing member 6 side is the same as the position of the laser light receiving end 32 of the first optical fiber 4 and the center position of the optical axis. Has become. The fiber lens 14 of the first optical fiber 4 has a spherical shape shown in FIG. 6, and the tip is a laser beam receiving end 32. The laser light receiving end 32 is arranged at the same height position as the plane of the active layer (not shown) of the laser diode 1.

In this example, when the fixing member mounting member 5 and the fixing members 6 and 7 are laser-welded, the upper surface of the fixing member mounting member 5 and the upper surfaces of the fixing members 6 and 7 are flush (within 100 μm of soil). So that This is preferable because the height of the laser welded portion 10 can be easily made uniform for each product.

In this embodiment, as shown in FIGS. 2 and 4, a bending preventing means 15 is formed on the fixing member mounting member 5 of the base 2. The radius prevention means 15 is formed on both sides of the first optical fiber 4 along the longitudinal direction of the first optical fiber 4. The radius preventing means 15 prevents the base 2 from bending. As shown in FIG. 4, the bending preventing means 15 is formed by forming a wall portion which is provided at least upward from the bottom 16 of the fixing member mounting member 5 in the longitudinal direction of the first optical fiber 4. It is.

As shown in FIG. 2, the deflection preventing means 15 is provided in the entire area in the longitudinal direction of the fixing member mounting member 5 (the area within the broken line frame B in FIG. 2). The bending prevention means 15 is provided on both sides of the axis part 33 connecting the laser light emitting end face of one end 31 of the laser diode 1 and the laser light receiving end 32 of the first optical fiber 4, and the laser. On both sides of the fixing member 6 located on the side close to the diode 1. Is also provided. The tip of the deflection preventing means 15 extends to the area where the LD bonding part 21 of the laser diode mounting member 8 is provided.

In the first embodiment, the deflection preventing means 15 is formed of a fixed member mounting member 5 and an integral member. 2 and 3, as shown in FIGS. 2 and 3, the walls constituting the deflection preventing means 15 and the fixing member fixing wall 35 form the fitting recesses 37a, 37 of the fixing members 6, 7 respectively. b is formed. The fixing members 6, 7 are welded and fixed to the fixing member mounting member 5 by the first laser welded portion 10 in a state of being fitted to the corresponding fitting concave portions 37a, 37b.

As shown in FIG. 3, for example, by forming the fitting recesses 37a, 37b of the fixing members 6, 7 and the insertion portion 38 of the sleep 3 into a hollow shape, the deflection preventing means is formed. Thus, the fixing member mounting member 5 in which the wall portion 15 and the fixing member fixing wall portion 35 are integrally formed is obtained.

Of the fixing members 6 and 7, the fixing member 6 located on the side closer to the laser diode 1 is, as shown in FIGS. 5A and 5B, a holding portion for holding the first optical fiber 4 from both sides. It is formed by an integral part with 28. As an example, as shown in FIG. 5B, the holding portion 28 of the fixing member 6 may be formed in an arm shape. Then, when the laser diode 1 and the first optical fiber 4 are aligned, when the first optical fiber 4 integrated with the sleep 3 is rotated with the laser welded portion 11a as a fulcrum, the laser welding is performed. The stress applied to the portion 11a is dispersed into the deformation stress of the arm of the holding portion 28, and the concentration of stress can be prevented.

In the first embodiment, of the fixing members 6 and 7, the fixing member 7 for fixing the first optical fiber 4 farther from the laser diode 1 includes a pair of fixing parts 7a and 7b. The fixed parts 7 a and 7 b of this pair are fixed to the fixing member mounting member 5 of the base 2 with the sleep 3 sandwiched from both sides. The fixed parts 7a and 7b are the first laser weld lib, The welding is fixed.

In the first embodiment, the fixing member fixing wall 35 of the fixing member mounting member 5 functions as a guide for guiding the movement of the fixing components 7a and 7b. A minute gap is interposed between the fixing member fixing wall portion 35 and the sleeve 3. The fixed parts 7 a and 7 b are fixed to the fixed member fixing wall 35 at the position of the first laser welded part 10.

In the first embodiment, the laser diode mounting member 8 of the base 2 is fixed to the upper surface of the thermo module 25. The fixing member mounting member 5 connected to the laser diode tower mounting member 8 is a thermo module.

The first optical fiber 4 is provided so as to protrude from the upper surface of the first optical fiber 4 in the longitudinal direction. The first optical fiber 4 is fixed on a fixing member mounting member 5 protruding from the thermomodule 25 side.

Further, in the first embodiment, the end face (rear end face) of the first optical fiber 4 far from the laser diode 1 is formed obliquely with respect to the optical axis of the first optical fiber 4.

A monitor photodiode 9 is provided so as to face the rear end face of the first optical fiber 4, and the monitor photodiode 9 is fixed to a monitor photodiode fixing portion 39. The mounting portion 39 is mainly made of alumina. Motor diode fixed part

Numeral 39 is fixed on the laser diode mounting member 8 of the base 2 by a solder material or the like.

Further, as shown in FIG. 7, the laser diode 1 is fixed on the heat sink 22 by a solder material 40 mainly composed of AuSn solder. The heat sink 22 is fixed on the laser diode mounting member 8 mainly by a solder material 41 having AuSn or AuSi. The heat sink 22 is made of a high thermal conductive material such as A 1 N or diamond. In addition, as shown in FIGS. 1 and 8, a second optical fiber 13 is arranged to face the other end 30 of the laser diode 1 with an interval therebetween. The ^second optical fiber 13 is fixed to a ferrule holder 58 while being supported and fixed to a ferrule 59.

As shown in FIG. 1, FIG. 2, and FIG. 8, between the other end 30 of the laser diode 1 and the second optical fiber 13, the other end 30 of the laser diode 1 is provided. A collimating lens 51 that converts laser light into parallel light is provided on the surface at intervals. The collimating lens 51 is mounted and fixed on the laser diode mounting member 8 of the base 2 while being supported and fixed by the lens holder 52. In FIG. 1, the lens holder mounting portion 47 is shown by hatching.

The laser diode mounting member 8 is provided with an isolator 53 via a gap with the collimating lens 51. The isolator 53 is fixed on the laser diode mounting member 8 via the isolator holder 54. A condensing lens 57 is provided on the emission side of the isolator 53 via an interval. A light transmitting plate 55 is provided between the isolator 53 and the condenser lens 57.

The condenser lens 57 condenses the light emitted from the laser diode 1 on the tip side of the second optical fiber 13. The condenser lens 57 is fixed to the lens holder 56. The light transmitting plate 55 provided on the incident side of the condenser lens 57 is made of sapphire glass or the like. Light transmission plate 5 5 The package 27 has a sealing function. In the first embodiment, the light transmitting plate 55 is disposed obliquely with respect to the optical axis of the condenser lens 57.

The operation of fixing the first optical fiber 4 to the fixing member mounting member 5 of the base 2 is performed, for example, as follows. First, the first optical fiber 4 and the laser diode 1 are aligned. With this alignment, the laser diode The distal end side of the first optical fiber 4 near the optical fiber 1 is clamped and fixed by the fixing member 6 from both sides.

This alignment is performed, for example, as follows. That is, the fixed component 6 is arranged in the fitting recess 37 a on the fixed component mounting member 5 of the base 2. Then, the first optical fiber 4 is arranged between the holding portions 28 (see FIG. 5) of the fixed component 6. Note that the interval between the holding portion 28 and the sleep 3 is about 0 to 2 μμηι. In this state, the rear end side of the first optical fiber 4 far from the laser diode 1 is gripped by, for example, an alignment jig. Using this alignment jig, the laser diode 1 and the first optical fiber 4 are aligned. At this time, the fixed component 6 can move in the X direction along the surface of the fixed member mounting member 5 of the base 2 together with the sleep 3.

After the alignment, the fixed component 6 is fixed to the fixed member mounting member 5 of the base 2 at the first laser welded portion 10. Then, the first optical fiber 4 side (specifically, the sleep 3 of the first optical fiber 4) is fixed to the fixed component 6 by welding at the second laser welding portion 11a. As described above, first, the side of the first optical fiber 4 close to the laser diode 1 is fixed to the fixing member mounting member 5. Note that the force for fixing the fixed component 6 to the fixed component mounting member 5 first and then welding and fixing the first optical fiber 4 side to the fixed component 6 or vice versa depends on the alignment. It should be selected in consideration of ease of alignment, alignment accuracy, etc.o

Thereafter, the end of the first optical fiber 4 farther from the laser diode 1 is fixed to the first part by the centering jig with the holding part (the laser welded part 11 a) held by the fixed part 6 as a fulcrum. Perform centering movement in the Y direction in the figure. Then, the first optical fiber 4 and the laser diode 1 are realigned.

Then, the fixing parts 7 a and 7 b are inserted into the fitting recesses 37 b in a manner guided by the fixing member fixing wall 35 of the fixing member mounting member 5 of the base 2, Place both sides of Sleep 3 gently. The fixing parts 7 a and 7 b are guided by a fixing member fixing wall 35, and are fixed to the fixing member of the base 2 in the X direction substantially perpendicular to the optical axis of the first optical fiber 4. Slide along the surface of the mounting member 5. By this slide movement, the distance between the fixed parts 7a and 7b of the sleep 3 on both sides and the side surface of the sleep 3 is adjusted to 0 to about 5 μm.

The fixed parts 7a and 7b are fixed to the fixed member fixing wall 35 by welding using a plurality of first laser welds 10. After that, the fixed parts 7a and 7b and the first optical fiber 4 side are fixed by laser welding (for example, YAG welding fixed) by the second laser welded part 11.

The centering operation is performed, for example, while oscillating laser light from the laser diode 1 and making the laser light incident and propagate on the first optical fiber 4. As described above, the rear end of the first optical fiber 4 far from the laser diode 1 is centered and moved using the centering jig and the like. The position where the intensity of the laser light propagating through the first optical fiber 4 becomes the highest is defined as the centering position.

The centering movement of the first optical fiber 4 is performed, for example, by attaching a stepping motor or the like to the centering jig, and measuring the intensity of the light propagating through the first optical fiber 4 and emitted by the light intensity detecting device. While monitoring, the amount of sleep 3 movement by the stepping motor may be adjusted by a person. Alternatively, both the light intensity detecting device and the driving device of the stepping motor may be connected to a computer, and the first optical fiber 4 may be automatically moved to the centering position by computer control.

In the semiconductor laser module of the first embodiment, the laser light emitted from one end 31 of the laser diode 1 is received by the first optical fiber 4 as in the conventional example. Then, while returning the light of the set wavelength to the laser diode 1, the light emitted from the other end 30 of the laser diode 1 is transmitted to the second optical fiber. The light is received by 13 and transmitted through the second optical fiber 13. At this time, also in this embodiment, the temperature of the laser diode 1 is controlled by the thermo module 25 as in the conventional example.

According to the first embodiment, the first optical fiber 4 is fixed to the base 2 by the fixing members 6 and 7 at two points at an interval in the longitudinal direction of the fiber. Therefore, the first optical fiber 4 can be appropriately centered and fixed on the base 2 with respect to the laser diode 1, and the displacement of the first optical fiber 4 can be suppressed.

Further, according to the first embodiment, the laser diode mounting member 8 of the base 2 that contacts the base side plate member 17 of the thermomodule 25 is the linear expansion coefficient of the fixed member mounting member 5 provided on the upper side. C u having a linear expansion coefficient between the copal and a 1 ₂ O ₃ that material (in other words having a linear expansion coefficient in the range between the linear expansion coefficient of the base side plate member 1 7 of thermo-module 2 5 W 10). Therefore, compared with the set Keru conventional direct contact with the base 2 formed by copal on the base side plate member 1 7 consisting of A 1 ₂ O _3, can be alleviated deflection of the base 2 caused by environmental temperature changes .

Therefore, according to the first embodiment, it is possible to suppress a decrease in the optical coupling efficiency between the laser diode 1 and the first optical fiber 4 due to a change in the use environment temperature.

Moreover, CuW 10 forming the laser diode mounting member 8 has a good thermal conductivity, and has a thermal conductivity that is about 10 times that of Copal. Therefore, in the first embodiment, the heat generated by the laser diode 1 is efficiently transmitted to the thermomodule 25 via the heat sink 22 and the laser diode mounting member 8. Therefore, the laser module 1 can be efficiently cooled by the thermo module 25. Therefore, according to the first embodiment, the power consumption of the laser diode 1 and the thermomodule 25 can be reduced, and a semiconductor laser module with low power consumption can be obtained. Further, the radius of the thermo module 25 can be reduced.

Further, according to the first embodiment, since the linear expansion coefficient of the laser diode mounting member 8 and the bottom plate 26 of the package 27 are the same, when the operating temperature of the semiconductor laser module changes, The same stress is applied to both the upper and lower sides of the thermo module 25, and the bending of the thermo module 25 is canceled. Therefore, according to the first embodiment, it is possible to more effectively suppress a decrease in the optical coupling efficiency between the laser diode 1 and the first optical fiber 4 due to a change in the use environment temperature.

Further, according to the first embodiment, the first laser welded portion 10 formed by laser welding the fixed member mounting member 5 of the base 2 and the fixed members 6 and 7 and the fixed members 6 and 7 and the three The second laser-welded portion 11 formed by laser welding with the package 3 is formed to have substantially the same height in the direction perpendicular to the package bottom plate 26. Therefore, even if a slight radius of the base 2 occurs, the radius does not cause the sleeve 3 to be largely displaced around the first laser welded portion 10 as a fulcrum. Therefore, it is possible to suppress the decrease in the optical coupling efficiency between the laser diode 1 and the optical fiber 2 even more efficiently. Further, according to the first embodiment, the optical fiber is attached to the fixing member mounting member 5 of the base 2. Along the lengthwise direction of 4, a radius preventing means 15 for preventing the base 2 from bending is provided. Therefore, the radius of the base 2 along the longitudinal direction of the optical fiber can be suppressed by the deflection preventing means 15.

In particular, in the semiconductor laser module of this embodiment, the light that is not emitted from the laser diode 1 emits the first light from the tip side of the first optical fiber 4. Light enters fiber 4. At the time of optical coupling between the laser diode 1 and the first optical fiber 4, it is extremely important to suppress the displacement between the laser diode 1 and the laser light receiving end 32 of the first optical fiber 4. Therefore, it is extremely important to suppress the radius of the base 2 in the axis portion 33.

Similarly, the displacement of the fixing position of the first optical fiber 4 by the fixing member 6 on the side closer to the laser diode 1 is the same as the displacement of the fixing position of the first optical fiber 4 by the fixing member 7 on the side farther from the laser diode 1. The optical coupling efficiency between the laser diode 1 and the first optical fiber 4 is greatly reduced as compared with the deviation. Therefore, it is extremely important to suppress the radius of the base 2 in the area where the fixing member 6 is provided.

Therefore, in the first embodiment, the means for preventing deflection 15 is provided with both sides of an axis portion 33 connecting the one end 31 of the laser diode 1 and the light receiving end 32 of the laser beam in the first optical fiber 4, It is provided in a region including both sides of the fixing member 6 located on the side closer to the laser diode 1. Thereby, the bending of the base 2 in the area where the axis portion 33 and the fixing member 6 are provided can be suppressed. Therefore, it is possible to effectively suppress the deflection of the base 2 in accordance with a change in the use environment temperature of the semiconductor laser module. Further, it is possible to extremely efficiently suppress a reduction in the optical coupling rate between the laser diode 1 and the first optical fiber 4. Further, in the first embodiment, the bending preventing means 15 is provided with a fixing member mounting member 5 At least an upper wall from the bottom 16 of the first optical fiber 4 is formed in the longitudinal direction of the first optical fiber 4. In addition, the deflection preventing means 15 is formed as an integral member with the fixed member mounting member 5. For this purpose, the bending prevention means 15 is composed of a separate component from the fixing member mounting member 5, and the strength is reduced by the connection between the bending prevention means 15 and the fixing member mounting member 5 as in the case of bonding them. 1/09741

26 does not occur. In addition, the radius prevention means 15 has a simple configuration, facilitating manufacture, and can effectively suppress the deflection of the base 2. Further, according to the first embodiment, it is close to the laser diode 1 The fixing member 6 for supporting and fixing the first optical fiber 4 on the side was formed as an integrated component having a holding portion 28 for holding the first optical fiber 4 from both sides. Therefore, since the connecting portion 49 connecting both sides of the holding portion 28 works as a deflection suppressing member, the bending of the base 2 in the X direction in FIGS. 2 and 5 can be further suppressed. . Therefore, according to the first embodiment, it is possible to suppress the decrease in the optical coupling efficiency between the laser diode 1 and the first optical fiber 4 even more efficiently.

Further, according to the first embodiment, the fixing member 7 for fixing the first optical fiber 4 farther from the laser diode 1 is a pair of the fixing members 7 fixed to the base 2 with the sleep 3 sandwiched from both sides. The fixed parts are 7a and 7b. Therefore, by aligning and fixing the first optical fiber 4 to the laser diode 1 using the above-described fixing method, the YAG welding of the fixed parts 7a and 7b and the first optical fiber 4 side is performed. The amount of movement of the first optical fiber 4 can be reduced. Therefore, when the first optical fiber 4 side is fixed by the fixing parts 7a and 7b, there is almost no displacement of the first optical fiber 4 (sleep 3).

Therefore, according to the first embodiment, the alignment work involved in manufacturing the semiconductor laser module can be performed accurately, the work time can be extremely shortened, and the cost can be reduced accordingly.

Further, according to the first embodiment, the fixing member mounting member 5 of the base 2 is farther from the thermomodule 25 than the optical fiber mounting end to be mounted and fixed on the thermomodule 25 (in the optical fiber longitudinal direction). ) I have. Therefore, the portion (projecting portion) not in contact with the thermo module 25 is not affected by the bending of the thermo module 25.

In the first embodiment, the first optical fiber 4 is fixed to a fixing member mounting member 5 protruding from the thermomodule 25. As a result, the first optical fiber 4 becomes extremely insensitive to the bending of the thermo module 25, and the optical coupling efficiency between the laser diode 1 and the first optical fiber 4 is reduced even more efficiently. Can be suppressed.

Further, according to the first embodiment, the fixing member mounting member 5 is formed of Kovar. Kovar has almost the same linear expansion coefficient as that of the first optical fiber 4 and has excellent laser weldability. For this reason, it is possible to prevent the first optical fiber 4 from being adversely affected by a difference in linear expansion coefficient from the first optical fiber 4. Further, the laser welding workability with the sleep 3 is good, and the semiconductor laser module can be manufactured with a low manufacturing cost. Further, according to the first embodiment, the first optical fiber 4 Thus, the laser light of the laser diode 1 is fed back to the laser diode 1. Therefore, the distance between the end of the first optical fiber 4 (laser light receiving end 32) and one end 31 of the laser diode 1 can be made very short, and a semiconductor laser with small noise and good wavelength stability can be obtained. It can be a module.

Further, according to the first embodiment, since the rear end face of the first optical fiber 4 farther from the laser diode 1 is formed obliquely with respect to the optical axis of the first optical fiber 4, the first light The light reflected on the rear end face of the fiber 4 can be prevented from returning to the laser diode 1 side, and the output from the laser diode 1 can be stabilized.

Further, in the first embodiment, the collimating lens 51 and the focusing lens 57 are An isolator 53 is provided between them. Therefore, it is possible to reliably suppress the laser light from returning to the laser diode 1 from the second optical fiber 13 side, and to stabilize the output of the semiconductor laser module.

Further, the light transmission plate 55 provided on the incident end side of the second optical fiber 2 is disposed obliquely with respect to the optical axis of the light collection lens 57. Therefore, the laser beam reflected by the light transmitting plate 55 can be prevented from returning to the laser diode 1, and the output of the semiconductor laser module can be further stabilized. As described above, in the first embodiment, the laser diode 1 and the first optical fiber 4 can be optically coupled with high accuracy regardless of a change in the use environment temperature. A highly reliable semiconductor laser module with low noise, high output and good wavelength stability is obtained. Therefore, when a Raman amplifier is configured using the semiconductor laser module of the first embodiment as an excitation light source, this Raman amplifier can be an excellent Raman amplifier suitable for wavelength division multiplexing transmission. The configuration of a second embodiment of such a semiconductor laser module is shown in a perspective view with a package 27 partially omitted. The second embodiment is configured substantially in the same manner as the first embodiment. The difference between the second embodiment and the first embodiment is that the thermo-module 25 has a higher laser beam intensity than the first embodiment. It is formed so as to be long in the axial direction so that the end of the base 2 on the rear end side of the first optical fiber 4 does not protrude from the thermomodule 25.

With this configuration, in the semiconductor laser module of the second embodiment, the entire lower surface of the laser diode mounting member 8 of the base 2 is brought into contact with the base side plate 17 of the thermomodule 25.

The semiconductor laser module of the second embodiment has the entire lower surface of the laser diode mounting member 8 of the base 2 in contact with the thermomodule 25. However, since the other configuration is the same as that of the first embodiment, the second embodiment can also provide substantially the same effects as those of the first embodiment.

FIG. 10 is a perspective view showing a fixing structure of the first optical fiber 4 in the third embodiment of the semiconductor laser module according to the present invention. Also, a plan view of the fixed configuration is shown in FIG. FIG. 12 shows an exploded view of the configuration of the base 2 in the third embodiment. The third embodiment is substantially the same as the first embodiment. The difference between the third embodiment and the first embodiment is that the fixing member mounting member 5 and the laser diode mounting member constituting the base 2 are different. That is, the shape of FIG. 8 is configured as shown in FIG. 10 to FIG.

That is, in the third embodiment, the deflection preventing means 15 is formed by both the fixing member mounting member 5 and the laser diode mounting member 8. Both sides of the axis part 33 connecting the one end 31 of the laser diode 1 to the light receiving end 32 of the laser light in the first optical fiber 4 and the side part of the fixing member 6 located on the side close to the laser diode 1 The radius prevention means 15 provided on both sides are constituted by a laser diode mounting member 8 and an integral member.

In the embodiment of FIG. 12 described above, three first laser welded portions 10 are provided at each of the fixing portions of the fixing member mounting member 5 and the fixing members 6 and 7. In the third embodiment, two fixing portions are provided at each of the above fixing portions. As described above, in the semiconductor laser module of the present invention, the number of laser welds 10 at each of the fixing portions is not particularly limited, and is appropriately set.

The third embodiment can also provide substantially the same effects as the first embodiment. Note that the present invention is not limited to each of the above embodiments, but can adopt various embodiments. For example, in each of the above embodiments, the deflection preventing means 15 One side of the axis 1 33 connecting one end 3 1 of the diode 1 to the light receiving end 32 of the laser beam in the first optical fiber 4 and the side of the fixing member 6 located on the side close to the laser diode 1 It is formed in a region including both sides. However, alternatively, the radius preventing means 15 is provided along at least one side of at least one side of the first optical fiber 4, at least along a part of the longitudinal direction of the optical fiber, and the radius of the base 2 is provided. The configuration may be such that only the configuration of the embodiment is prevented.

If the deflection preventing means 15 is provided at least on one side of the axis portion 33, the deflection of the base 2 in the axis portion 33 can be suppressed, and the laser diode 1 and the first A decrease in optical coupling efficiency with the optical fiber 4 can be efficiently suppressed. Therefore, it is preferable to provide the bending prevention means 15 at least on one side of the axis portion 33 (more preferably, on both sides of the axis portion 33).

In addition, at least one of the fixing members (the fixing members 6 and 7 in the above-described embodiments) which support the first optical fiber 4 at positions spaced from each other in the longitudinal direction of the first optical fiber 4. If the bending preventing means 15 is provided on one side of the fixing member located closest to the laser diode 1, the displacement of the support position of the first optical fiber 4 on the side near the laser diode 1 can be suppressed. . Therefore, it is possible to efficiently suppress a decrease in optical coupling efficiency between the laser diode 1 and the first optical fiber 4 due to the bending of the base 2. Therefore, it is preferable to provide the bending prevention means 15 on one side of the fixing member located closest to the laser diode 1.

Further, in the above-described first embodiment, the bending preventing means 15 is configured by forming a wall standing upright from the bottom 16 of the fixing member mounting member 8 in the longitudinal direction of the optical fiber. However, the configuration of the deflection preventing means 15 is not particularly limited, and may be a configuration other than the embodiment. For example, rod-shaped or square-shaped deflection prevention The means 15 may be provided by being fixedly adhered to the fixing member mounting member 5. Further, in each of the above embodiments, the base 2 is configured to have the fixing member mounting member 5 and the laser diode mounting member 8. However, the configuration of the base 2 is not particularly limited to the embodiment. For example, the base 2 may be formed of one member having a fixing member mounting portion for mounting the fixing members 6 and 7.

Also in this case, the first optical fiber 4 is fixed by the fixing members 6 and 7 at two points with an interval in the longitudinal direction. As a result, the first optical fiber 4 can be properly aligned and fixed with respect to the laser diode 1 as compared with the conventional example.

Further, as described above, even when the base 2 is formed by one member having the fixing member mounting portion, the first laser welded portion 10 and the second laser welded portion 11 are The height in the direction perpendicular to the package bottom plate 26 should be substantially the same. By doing so, it is possible to reduce the displacement of sleep 3 that occurs when base 2 curves, as compared with the conventional semiconductor laser module, and the light between laser diode 1 and first optical fiber 4 can be reduced. A reduction in coupling efficiency can be suppressed.

Furthermore, in each of the above embodiments, the first optical fiber 4 has a configuration in which the fiber lens 14 has a spherical shape. However, the shape of the fiber lens 14 of the first optical fiber 4 is not particularly limited and may be another shape. As shown in FIG. 14, for example, the fiber lens 14 may be a wedge-shaped anamorphic (rotationally asymmetric) lens or may be a non-wedge-shaped anamorphic lens. In FIG. 14, 14a indicates a ridge line.

Further, in each of the above embodiments, a fiber lens 14 is formed on the distal end side of the first optical fiber 4 so that the first optical fiber 4 and the laser diode 1 are optically coupled to each other. Are combined. However, alternatively, a lens system similar to the collimator lens 51 or the condenser lens 56 is provided between the first optical fiber 4 and the laser diode 1 so that the first optical fiber 4 and the laser diode 1 are connected to each other. It is also possible to have a configuration in which the light is optically coupled.

Further, in each of the above embodiments, the collimator lens 51, the isolator 53, and the condenser lens 57 are provided between the second optical fiber 13 and the other end 30 of the laser diode 1. . However, as an alternative embodiment, for example, the collimating lens 51 and the isolator 53 may not be used. Instead of providing the condenser lens 57, a fiber lens 23 may be formed on the distal end side of the second optical fiber 13 as shown in FIG. 15, for example. Also in this case, the fiber lens 23 may be an anamorphic lens as shown in FIG. 15 or a conical shape like the fiber lens 14 of the first optical fiber 4 in each of the above embodiments. It can be a fiber lens.

Further, in each of the above embodiments, the fixing member mounting member 5 is provided so as to protrude from the rear end side of the first optical fiber 4 with respect to the laser diode mounting member 8, and the monitor photodiode 9 and the monitor photodiode are fixed to the protruding region. Section 39 is provided. As an alternative embodiment, as shown in FIG. 13, for example, as shown in FIG. 13, the fixing member mounting member 5 is formed so as to protrude from the laser diode 'mounting member 8, and the monitor photo diode fixing portion 39 is separate from the base 2. May be provided.

When the fixing member mounting member 5 is formed so as to protrude from the laser diode mounting member 8, the fixing members 6, 7 and the sleeve 3, the first optical fiber 4, which are mounted on the protruding portion, are attached to the laser diode mounting member. 8 can be suppressed from being affected. Therefore, it is possible to more efficiently suppress a decrease in the optical coupling efficiency between the laser diode 1 and the first optical fiber 4. If the protrusion length L of the fixing member mounting member 5 is too long, the bonding strength to the laser diode mounting member 8 will be insufficient. For this reason, there is a possibility that the adhesive may be peeled off when the protrusion is subjected to vibration. Therefore, it is preferable to set L ≦ 5 mm.

When the fixing member mounting member 5 is formed so as to protrude from the laser diode mounting member 8, as shown in FIG. 13, the fixing member mounting member 5 is located below the fixing member 6 located closest to the laser diode 1. By forming the reinforcing portion 20, vibration of the fixed member mounting member 5 in the Y direction in the figure can be suppressed.

That is, when the reinforcing portion 20 is formed on the laser diode mounting member 8, even if the Y-direction vibration is applied to the fixing member mounting member 5, the fulcrum of this vibration is more laser-induced than the fixing member 6. Can be far from Diode 1. As a result, it is possible to suppress a decrease in optical coupling efficiency between the laser diode 1 and the first optical fiber 4.

Further, by forming the reinforcing portion 20 and forming the laser diode mounting member 8 long in the longitudinal direction of the first optical fiber 4, the contact area between the laser diode mounting member 8 and the fixing member mounting member 5 is increased. be able to . Therefore, both can be firmly fixed mechanically. Since the lower surface of the reinforcing portion 20 is not in contact with the thermo module 25, the reinforcing portion 20 is not affected by the bending of the thermo module 25.

Further, the shape of the reinforcing portion 20 is not particularly limited, and may be another shape. For example, it may have a rectangular parallelepiped shape as shown in FIG. 13 or may have a configuration having a tapered surface as shown by oblique line A in FIG. When the fixing member mounting member 5 is formed so as to protrude from the laser diode mounting member 8, the capturing portion 20 may not be provided. However, since there is an advantage by forming the reinforcing portion 20 as described above, it is more preferable to provide the reinforcing portion 20. Further, in each of the above embodiments, the fixing member 6 located closest to the laser diode 1 is formed as an integrated component having the holding portion 28 as shown in FIG. 5, but the structure of the fixing member 6 Is not particularly limited, and may have another configuration. However, when the fixing member 6 is configured as in each of the above embodiments, the radius of the base 2 in the X direction can be suppressed.

Further, in the above embodiment, the laser diode mounting member 8 and the bottom plate 26 of the package 27 are made of the same material to have the same linear expansion coefficient, but the laser diode mounting member 8 and the bottom plate 2 of the package 27 are the same. As long as the coefficient of linear expansion of 6 is substantially the same, different materials may be used. It is preferable that the linear expansion coefficients of the laser diode mounting member 8 and the bottom plate 26 of the package 27 be substantially the same, but they may be different from each other.

Further, in the above embodiment, the lead terminal 60 is formed to protrude outward from the side wall of the package 27, but the lead terminal 60 may be formed to extend downward from the side wall of the package 27. The arrangement form and shape of the lead terminals 60 and the shape of the package 27 are arbitrarily designed.

Furthermore, in the above example, the example in which the semiconductor laser module of each embodiment is applied to a Raman amplifier has been described. However, the semiconductor laser module of the present invention is not only used as an excitation light source for a Raman amplifier, but also used for other than a Raman amplifier. It is applied to various light sources for optical communication, such as an excitation light source for an amplifier and a signal light source.

Industrial applicability

As described above, the semiconductor laser module and the Raman amplifier using the semiconductor laser module according to the present invention are suitable for use in optical communication and the like, which obtain a stable laser output while suppressing the influence of temperature change. I have.

Claims

Range of request

1. A semiconductor laser module configured as follows:

Base;

A second optical fiber disposed opposite to the other end of the laser diode to receive and transmit light emitted from the other end of the laser diode; wherein the first optical fiber has It is arranged toward one end of the laser diode,

The first optical fiber has a diffraction grating that reflects light having a set wavelength, and the light having the set wavelength among the lights emitted from one end of the laser diode is fed back to the laser diode. ,

The first optical fiber is fixed to the base by a fixing member at a plurality of points at intervals in the longitudinal direction of the optical fiber.

2. Among the fixing members provided at a plurality of positions at intervals in the longitudinal direction of the first optical fiber, the fixing member located on the side closest to the laser diode is the first member. 2. The semiconductor laser module according to claim 1, wherein the semiconductor laser module is formed as an integrated component having a holding portion for holding the optical fiber from both sides.

3. A semiconductor laser module configured as follows:

Package; A base housed in the package;

A laser diode mounted on the base;

A laser diode mounting member mounted and fixed in contact with an upper surface of the thermo module and mounting the laser diode; a fixing member coupled to the laser diode mounting member and mounting the fixing member; And a mounting member.

4. A semiconductor laser module configured as follows: ノ ^ ツケ ■ ~ ジ；

A base housed in the package;

A laser diode mounted on the base;

Here, the first optical fiber has a diffraction grating that reflects light of a set wavelength, and feeds back the light of the set wavelength to the laser diode among lights emitted from one end of the laser diode. A laser diode mounting member mounted and fixed in contact with an upper surface of the thermo module and mounting the laser diode; and the fixing member coupled to the laser diode mounting member. And a fixing member mounting member for mounting the

The bottom plate of the package is formed of a material having substantially the same coefficient of linear expansion as the laser diode mounting member of the base.

5. A semiconductor laser module configured as follows;

Knockage;

A base housed in the package;

A laser diode mounted on the base; A first optical fiber mounted on the base, arranged with the fiber tip end toward one end of the laser diode, and optically coupled to the laser diode;

A fixing member mounted on the base, for fixing the first optical fiber to the base while holding the first optical fiber from both sides;

A second optical fiber disposed opposite to the other end of the laser diode to receive and transmit light emitted from the other end of the laser diode;

The first laser welded portion and the second laser welded portion have substantially the same height in a direction perpendicular to the package bottom plate.

6. A plurality of fixing members are provided,

4. The semiconductor laser module according to claim 3, wherein the plurality of fixing members fix the first optical fiber to the base at a plurality of positions spaced from each other in a longitudinal direction of the optical fiber.

7. A plurality of fixing members are provided,

5. The semiconductor laser module according to claim 4, wherein the plurality of fixing members fix the first optical fiber to the base at a plurality of positions spaced from each other in a longitudinal direction of the optical fiber.

8. A plurality of fixing members are provided.

6. The semiconductor laser module according to claim 5, wherein the plurality of fixing members fix the first optical fiber to the base at a plurality of positions spaced from each other in a longitudinal direction of the optical fiber.

9. A semiconductor laser module configured as follows:

Base;

A thermo module on which the base is mounted; wherein the first optical fiber has a diffraction grating that reflects light having a set wavelength, and the first optical fiber is set out of light emitted from one end of the laser diode. A wavelength of light is fed back to the laser diode, and at least a part of the base is positioned at one or both sides of the side of the first optical fiber; Along the direction

A bending preventing means for preventing bending of the base is provided.

10. The radius preventing means is provided on one or both sides of an axis portion connecting a laser light emitting end face on one end side of the laser diode and a light receiving end of the laser light in the first optical fiber. A semiconductor laser module according to claim 9, wherein

11. A plurality of fixing members are provided to support the first optical fiber at positions spaced from each other in the longitudinal direction of the first optical fiber and to fix the first optical fiber to the base.

10. The semiconductor laser module according to claim 9, wherein the deflection preventing means is provided on one or both sides of a side of the fixing member located closest to the laser diode.

12. The base is configured to include a fixing member mounting member for mounting the fixing member, and a laser diode mounting member for mounting the laser diode and contacting the thermomodule side.

10. The semiconductor laser module according to claim 9, wherein said fixing member mounting member and said deflection preventing means are formed by an integral member.

13. The claim range of claim 9, wherein the radius prevention means is a wall formed in the longitudinal direction of the first optical fiber, the wall being formed at least above the bottom of the fixing member mounting member and formed in the longitudinal direction of the first optical fiber. Semiconductor laser module.

Claim 4. Claim 3 of claim 3, wherein at least one of the fixing member mounting member of the base, the fixing member, and the deflection preventing means is formed of a Fe—Ni—Co alloy. Semiconductor laser module.

15 5. Semiconductor laser module configured as follows;

Base;

A laser diode mounted on the base; a laser diode mounted on the base, with a tip end of the fiber facing toward one end of the laser diode, and optically coupled to the laser diode; The first optical phoenix

A thermo module on which the base is mounted; wherein the first optical fiber has a diffraction grating for reflecting light of a set wavelength, and the light emitted from one end of the laser diode is The light having a set wavelength is fed back to the laser diode, and the first optical fiber is close to the laser diode when the first optical fiber and the laser diode are aligned. It is clamped and fixed from both sides by fixing members at each of the side and the far side.

Each of the fixed components and the first optical fiber side are fixed by laser welding.

16. A guide section is provided on the base at a fixed portion of the first optical fiber farther from the laser diode with an interval from the first optical fiber side, and is guided by the guide section. 16. The fixing device according to claim 15, wherein the fixed component is fixed to the guide portion with both sides of the first optical fiber arranged side by side. The semiconductor laser module according to the above.

17. The base has a portion that protrudes beyond the portion mounted in contact with the thermomodule beyond the upper surface of the thermomodule in the longitudinal direction of the first optical fiber. 2. The semiconductor laser device according to claim 1.

18. The base is mounted on the base of the thermo-module so as to be in contact with and fixed to the laser diode, and has a laser diode mounting member mounted thereon, and a fixing member mounted on the laser diode mounting member and mounting the fixing member. And a member,

The semiconductor laser module according to claim 17, wherein a portion protruding from an upper surface of the thermomodule serves as a fixing member mounting member.

19. The laser diode mounting member has a force-retaining portion for mechanically reinforcing the fixing member located on the side closest to the laser diode, and the lower surface of the reinforcing portion is formed as a non-contact surface with respect to the thermo module. The semiconductor laser module according to claim 18, wherein:

20. The semiconductor laser module according to claim 1, wherein a rear end face of the first optical fiber farther from the laser diode is formed obliquely with respect to an optical axis of the first optical fiber.

21. A condenser for condensing light emitted from the laser diode to the tip side of the second optical fiber between the second optical fiber and a laser diode end face facing the second optical fiber. The semiconductor laser module according to claim 1, further comprising a lens.

22. The semiconductor laser module according to claim 21, wherein a collimating lens is provided between a laser diode end face facing the second optical fiber and a condenser lens.

23. A collimating lens is provided between the laser diode end face facing the second optical fiber and the converging lens with an interval between the converging lens and the collimating lens. 21. The semiconductor laser module according to claim 21, wherein an isolator is provided between the semiconductor laser module and the optical lens.

24. The semiconductor according to claim 21, wherein a light transmitting plate is provided on an incident side of the condenser lens, and the light transmitting plate is disposed obliquely with respect to an optical axis of the condenser lens. Laser module.

25. The fiber lens according to claim 1, wherein a fiber lens is formed on a tip side of the second optical fiber, and a tip side of the fiber lens and a laser light emitting end face of the laser diode are arranged to face each other. Semiconductor laser module

26. A Raman amplifier using the semiconductor laser module according to claim 1 as an excitation light source.

27. A Raman amplifier using the semiconductor laser module according to claim 3 as an excitation light source.

28. A Raman amplifier using the semiconductor laser module according to claim 4 as an excitation light source.

29. A Raman amplifier using the semiconductor laser module according to claim 5 as an excitation light source.

30. A Raman amplifier using the semiconductor laser module according to claim 9 as an excitation light source.

31. A Raman amplifier using the semiconductor laser module according to claim 15 as an excitation light source.