JP2003163404A - Light emitting module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting module which is accommodated within a small size package manufactured easily and assures stable operation of a light emitting element depending on the temperature of the light emitting element in the temperature of an optical isolator. <P>SOLUTION: The light emitting module 1 comprises a substrate 3, a sub-assembly including the light emitting element 6, an optical lens element 7 and the optical isolator element 8 provided on the substrate 3, a temperature adjusting element 2 to mount the sub-assembly, a package 20 which is provided with a package bottom surface 20a to mount the temperature adjusting element 2 in order to mount the same element 2 within the package bottom surface 20a, and an optical fiber 15 to input and transfer the light emitted from the light emitting element 6. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting module used for optical communication. More specifically, the present invention relates to a light emitting module including a light emitting element, a temperature control element, an optical system, etc., which are housed in a package.

[0002]

2. Description of the Related Art FIG. 4 is a side sectional view showing the structure of a conventional light emitting module.

A conventional light emitting module includes a light emitting element 6 for emitting light, an optical lens 8 and an optical isolator 9.
The substrate 3 is integrally formed and is fixed to the lower surface 20a of the package 20 via the Peltier element 2. The package 20 is provided with a window 20b that allows light to pass therethrough, and the light emitted from the light emitting element 6 passes through the optical lens 8, the optical isolator 9, and the window 20b and is led out of the package 20. A ferrule 14 that receives one end of the optical fiber 15 is provided outside the package 20 provided with the window 20b via a ferrule holder 13, and is guided to the outside through the window 20b. The light is incident on the optical fiber 15. Therefore, the light emitting element 6, the first optical lens 8, the optical isolator 9, the window 20
b, one end of the optical fiber 15 received by the ferrule 14 is arranged in this order along the optical axis A of the light emitted from the light emitting element 6.

The optical isolator 9 is an element having a characteristic of allowing almost all light in a predetermined wavelength band to pass in one direction. Almost no light passes in the opposite direction, which is the opposite of one direction. In the light emitting module 1 shown in FIG. 4, the emitted light emitted from the light emitting element 6 and passing through the optical lens 8 is passed only in the direction of the window 20b. Therefore, in the light emitting module 1, noise light propagating from the optical fiber 15 toward the light emitting element 6 through the window portion 20b is blocked, so that the operation of the light emitting element 6 is stabilized. And Peltier element 2
Is operated so as to maintain the temperature of the light emitting element 6 at a constant temperature based on a temperature detection signal from a thermistor arranged close to the light emitting element 6, and makes the operation of the light emitting element 6 more stable. .

Since the optical isolator 9 is expensive, increasing the opening diameter of the optical isolator 9 is not suitable because it increases the cost of the light emitting module 1. Therefore, in the light emitting module 1, the optical lens holder 8 is provided so that the optical isolator 9 can be accurately positioned at the optimum position with respect to the optical axis A of the light passing through the optical lens 8.
The contact portions where the optical isolator holder 10 and the optical isolator holder 10 contact each other are appropriately precision processed. Therefore, in the light emitting module 1, the outgoing light passing through the first optical lens 8 can be effectively incident on and passed through the optical isolator 9 without increasing the aperture diameter of the optical isolator 9.

[0006]

However, in the light emitting module 1 of the prior art, it is costly to increase the cost of the light emitting module 1 if the contact portions of the first optical lens holder 7 and the optical isolator holder 9 are precisely processed. It was connected.

The optical isolator 9 has a characteristic that almost all light in a predetermined wavelength band is transmitted in one direction, a characteristic that almost no light is transmitted in the opposite direction opposite to the one direction, and the emission of the light emitting element 6. The emitted light changed depending on the temperatures of the optical isolator 9 and the light emitting element 6, and did not correspond to each other.

Therefore, when a temperature deviation occurs between the light emitting element 6 and the optical isolator 9, the predetermined wavelength band of the light that the optical isolator 9 allows to pass in one direction changes, or in the other direction. There is a problem that the output light passing therethrough is reduced and therefore the wavelength band of the output light of the light emitting module is changed or the output light is reduced. At the same time, the property of hardly passing light in the opposite direction opposite to the one direction is deteriorated, and the optical fiber 1
Since the noise light propagating from 5 to the light emitting element 6 through the window 20b is less likely to be blocked, there is a problem that the operation of the light emitting element 6 becomes unstable.

In Japanese Patent Laid-Open No. 06-120609, a unit 100 in which a semiconductor laser 1, an optical lens 2, an optical isolator 3 and a ferrule 4 are integrated is soldered and fixed on a Peltier element 10 for temperature control. An invention relating to a light emitting device contained in the package 11 is disclosed. Also in the light emitting device of the invention, since the structure requiring heat capacity such as the optical lens 2 is interposed between the semiconductor laser 1 and the optical isolator 3, and the ferrule 5 is further included in the package 11, it is necessary to make the package 11 large. was there. Also, ferrule 5 is package 11
Since a part of the optical fiber 12 received by the ferrule 5 is metal-plated, the package 11
And had to be sealed with solder. In the present invention, the manufacturing method becomes complicated and therefore the cost is increased.

Therefore, the present invention solves the above-mentioned problems in the light emitting module 1 of the prior art, is simple in manufacture and is configured in a small package, and the optical isolator is not affected by the ambient temperature, and the temperature of the light emitting element is not affected. It is an object to provide a light emitting module in which the operation of the light emitting element is stable by following the above.

[0011]

In order to solve the above-mentioned problems, a light-emitting module according to a first aspect of the present invention comprises a substrate and a sub-assembly including a light-emitting element, an optical lens element and an optical isolator element provided on the substrate. A temperature control element on which the sub-assembly is mounted, a package including a bottom surface on which the temperature control element is mounted, and a package on which the temperature control element is mounted on the bottom surface, and an optical fiber which allows the light emitted from the light emitting element to enter and propagate. And The light emitting module according to the invention of claim 1 is characterized in that the optical isolator element is directly fixed to the substrate.

According to the light emitting module of the first aspect, since the optical isolator element is directly fixed to the substrate, the heat capacity of the portion interposed between the light emitting element and the optical isolator element is reduced. Therefore, it is suitable for making the temperature of the optical isolator element follow so that it becomes equal to the temperature of the light emitting element. Further, since the optical isolator element is directly fixed to the substrate, it is not necessary to provide a contact portion for fixing the optical isolator element to the optical lens element by performing a precise polishing process, which simplifies the manufacturing process. Can be transformed.

According to a second aspect of the present invention, there is provided a light emitting module according to the first aspect, wherein the optical lens element holds the optical lens that collects the light emitted from the light emitting element and makes it enter the optical isolator element, and the substrate holding the optical lens. The optical isolator element is composed of an optical isolator that passes light in a predetermined wavelength band only in one direction and an optical isolator holder that holds the optical isolator and is fixed to the substrate. The optical isolator holder is made of a material having a higher thermal conductivity than that of the optical lens holder.

According to the light emitting module of the second aspect, the optical isolator holder fixed to the substrate is formed of a material having a higher thermal conductivity than the optical lens holder fixed to the substrate. Therefore, it is more suitable for making the temperature of the optical isolator follow the temperature of the light emitting element provided on the substrate.

A light emitting module according to a third aspect is the light emitting module according to the first or second aspect, wherein the optical fiber is provided outside the package.

According to the light emitting module of the third aspect, since the optical fiber is provided outside the package, the package can be provided in a small size.

[0017]

The above objects and features of the present invention are as follows.
The preferred embodiments of the present invention, which will be described in detail below with reference to the accompanying drawings, will be easily apparent. The same components are designated by the same reference numerals.

[0018]

EXAMPLE FIG. 1 is a cross-sectional configuration diagram of a light emitting module 1 according to a first embodiment of the present invention. Light emitting module 1
Is a substrate 3, a subassembly 30 (see FIG. 2) including a light emitting element 6, an optical lens element 7 and an optical isolator element 8 provided on the substrate 3, and a temperature control element 2 mounting the subassembly 30. And the temperature control element 2
A package bottom surface 20a for mounting the temperature control element 2 on the package bottom surface 20a, and an optical fiber for propagating the emitted light of the light emitting element 6 to the outside of the package 20. 15 and. Hereinafter, the light emitting element 6 will be described as a semiconductor light emitting element 6 that receives an electrical drive signal and emits light according to the drive signal, and the temperature control element 2 will be described as a Peltier element 2.

The package 20 is provided with a window portion 20b which allows light to pass therethrough, and the emitted light of the semiconductor light emitting element 6 is provided with an optical lens element 7, an optical isolator element 9 and a window portion 2.
0b is sequentially passed to be led out of the package 20. The ferrule 14 that receives one end of the optical fiber 15 is provided outside the package 20 provided with the window 20b, and the light that passes through the window 20b and is guided to the outside is provided in the optical fiber 15. Is incident on. Therefore, the light emitting element 6, the first optical lens 8, the optical isolator 9, the window 20b, and one end of the optical fiber 15 received by the ferrule 14 are arranged in this order along the optical axis A of the light emitted from the semiconductor light emitting element 6. It is arranged.

The semiconductor light emitting element 6 has a resonator formed of an emitting surface and a reflecting surface which face each other. Most of the light oscillated by the resonator is emitted from the emission surface of the semiconductor light emitting element 6 (hereinafter referred to as emission light), and the light emitted from the emission surface of the resonator is emitted from the reflection surface. A part (hereinafter, referred to as monitor light) excluding the incident light is emitted. The wavelengths of the monitor light and the emitted light are equal, and the light intensities of the two show a reproducible constant correlation. The wavelength of the light emitted from the semiconductor light emitting device 6 is 1310 nm band or 1550 nm.
It is the nm band. In this case, the light emitting module 1 can be used as a light source in optical communication using an optical fiber made of quartz glass as an optical transmission line.

The substrate 3 has a mounting portion 3b and a wall portion 3a extending from one end of the mounting portion 3b in a substantially vertical direction, and is made of CuW having excellent heat conduction characteristics. Wall part 3 of mounting part 3b
A semiconductor light emitting element 6 is mounted at a position close to a via a chip carrier 5 also made of CuW. The semiconductor light emitting element 6 is mounted so that the optical axis of the emitted light of the semiconductor light emitting element 6 is emitted toward the wall portion 3a side along a predetermined axis A. Therefore, the wall portion 3a is provided with a through hole 3c that allows the emitted light of the semiconductor light emitting element 6 to pass therethrough, and the emitted light is not blocked by the wall portion 3a and the window portion 2 is not blocked.
Pass to the 0b side.

Further, the thermistor 11 (see FIG. 2) is mounted on the chip carrier 5 so as to be close to the semiconductor light emitting element 6. The thermistor 11 is an element that detects and outputs the temperature of the proximity portion on which the thermistor 11 is mounted as an electric signal (hereinafter, referred to as a temperature detection signal).

For this reason, the semiconductor light emitting element 6 of the light emitting module 1 is controlled by a controller (not shown) so that the Peltier element 2 is controlled so as to have a constant temperature such as 25 ± 1 ° C. based on the temperature detection signal from the thermistor 11. Control via (A
TC), so that the operation of the semiconductor light emitting device 6 is stably performed.

In particular, when the semiconductor light emitting element 6 generates heat by driving the light emitting module 1 for a long time, or the environmental temperature in which the light emitting module 1 is installed is, for example, 1.
Even when the temperature is lowered to 0 ° C., the semiconductor light emitting element 6 is brought to the certain temperature shown above through the Peltier element 2, so that the oscillation of the semiconductor light emitting element 6 is stabilized and the semiconductor light emitting element 6 is stable. The wavelength band and the light intensity of the emitted light are stable.

Further, on the chip carrier 5, a photodiode 4 for receiving light on the optical axis of the monitor light emitted from the reflecting surface of the semiconductor light emitting element 6 and outputting an electric signal according to the received light intensity. But the photodiode carrier 4a
Is installed through.

Therefore, in the light emitting module 1, the state of the light emitted from the semiconductor light emitting element 6 can be detected by monitoring the electric signal output from the photodiode 4.

FIG. 2A is a sectional view of the sub-assembly 30. Further, FIG. 2B is an exploded sectional configuration diagram in which the optical lens element 7 and the optical isolator element 8 of the subassembly 30 are separated from the substrate 3. The optical lens element 7 includes an optical lens 71 that collects light emitted from the semiconductor light emitting element 6 and makes it enter the optical fiber 15, and a cylindrical optical lens holder 72 that holds the optical lens 71. The optical isolator element 8 includes an optical isolator 81 and a substantially cylindrical optical isolator holder 82 that holds the optical isolator 81.

The optical isolator 82 has a low insertion loss characteristic which allows almost all light in a predetermined wavelength band such as 1310 nm band or 1550 nm band to pass in one direction. And, in the opposite direction opposite to the one direction, it has an isolation characteristic that hardly allows light to pass therethrough. The low insertion loss characteristic is an insertion loss of 1 dB or less in a bandwidth of several nm in the above wavelength band, and the isolation characteristic is a cutoff characteristic of about 35 dB or more in all wavelength bands.

In the light emitting module 1 shown in FIG. 1, the light emitted from the light emitting element 6 passes through the optical lens element 7 only in the direction of the window 20b. Therefore, the light emitting module 1 includes the semiconductor light emitting element 6 from the optical fiber 15 through the window 20b.
Since the emitted light propagating in the direction of is blocked, the operation of the semiconductor light emitting element 6 is stabilized.

Returning to FIG. 2A, in the light emitting module 1 of the present embodiment, the optical lens element 7 and the optical isolator element 8 are opposite to the inner side surface 3e of the wall portion 3a on which the semiconductor light emitting element 6 is mounted. On the outer side surface 3d of the optical lens holder 71 and the optical isolator holder 8 respectively.
It is provided by abutting and fixing the first end face 81a. First, the optical lens element 7 is adjusted to the optimum position for collecting the emitted light of the semiconductor light emitting element 6 with the one end surface 71a of the optical lens holder 71 abutting on the outer surface 3d of the wall portion 3a. Then, the outer side surface 3d and the optical lens holder 71 are welded and fixed by a YAG laser. next,
A position where the emitted light of the semiconductor light emitting element 6 which has passed through the optical lens element 7 through the isolator element 8 in the state where the end surface 81a of the optical isolator holder 81 is in contact with the outer surface 3d of the wall portion 3a efficiently passes through the window portion 20b. After aligning to YAG
This is realized by welding and fixing the optical isolator holder 81 and the outer peripheral surface of the outer surface 3d to which the optical lens element 7 is fixed by a laser. Here, in order to precisely align the optical lens element 7 and the optical isolator element 8 with respect to the optical axis A of the emitted light of the semiconductor light emitting element 6, the outer surface 3 of the substrate 3 is
d, the one end surface 71a of the optical lens holder 71 and the end surface 81a of the optical isolator holder 81 are subjected to precise polishing processing so as to be flat. In this case, the outer surface 3d of the substrate 3 only needs to be subjected to a polishing process only on a portion where the optical lens holder 71 and the optical isolator holder 81 are in contact with each other.

As described above, in the light emitting module 1 of the present embodiment, the heat capacity of the portion interposed between the semiconductor light emitting element 6 and the optical isolator 82 is reduced,
This is suitable for making the temperature of the optical isolator 82 follow so that it becomes equal to the temperature of the semiconductor light emitting element 6. Therefore, the light emitted from the semiconductor light emitting element 6 in the predetermined wavelength band can be efficiently propagated to the optical fiber 15 side through the optical isolator 82. Further, the isolation characteristic for blocking the light propagating from the optical fiber 15 through the window portion 20b toward the semiconductor light emitting element 6 does not deteriorate, so that the operation of the semiconductor light emitting element 6 is stabilized.

Further, when the optical isolator holder 81 is made of a material having a higher thermal conductivity than that of the optical lens holder 71, the temperature of the optical isolator 82 is made to follow the temperature of the semiconductor light emitting element 6. It is more preferable. In this case, for example, the optical lens holder 81
Is made of SUS, and the optical isolator holder 82 is
It can be 0T.

Further, in the light emitting module 1 of this embodiment, the optical isolator holder 81 is directly fixed to the outer surface 3d of the substrate 3. Therefore, as in the case where the optical isolator holder 81a is brought into contact with the other end surface 71b opposite to the one end surface 71a of the optical lens holder 71 to fix the optical isolator element 8, the optical lens holder 71 is fixed.
It is not necessary to perform precision polishing on the other end surface 71b of the. Therefore, in the light emitting module 1 of this embodiment, the manufacturing process can be simplified.

Returning to FIG. 1 again, in the light emitting module 1 of the present embodiment, the ferrule 14 that receives one end of the optical fiber 15 has the optical isolator element on the package outer surface 20c provided with the window 20b of the package 20. It is provided via the ferrule holder 13 after being aligned to the optimum position for the outgoing light that has passed through 8.

Therefore, since the light emitting module 1 does not have the ferrule 14 inside the package 20, the package 20 can be made small.

Here, the fixation between the ferrule 14 and the ferrule holder 13 and the fixation between the ferrule holder 13 and the package outer side surface 20c can be fixed by welding with a YAG laser. In this case, the ferrule 13 is formed by press-fitting a capillary made of ceramic into a cylinder made of metal, and the ferrule holder 13 is made of metal.
Further, on the outer side surface 20c of the package, the ferrule holder 13
It is preferable that the abutting portion and the welded portion are not subjected to gold plating or the like.

Next, a light emitting module 1 of the second embodiment different from the light emitting module 1 of FIG. 1 will be described. The description of the same parts as those of the light emitting module 1 in FIG. 1 will be omitted.

FIG. 5A is a sectional view of the subassembly 30 of the light emitting module 1 of the second embodiment.
Further, FIG. 5B is an exploded cross-sectional configuration diagram in which the optical lens element 7 and the optical isolator element 8 of the subassembly 30 are separated from the substrate 3.

In the light emitting module 1 of the second embodiment,
The optical lens element 7 includes the through hole 3 of the wall portion 3a of the substrate 3.
It is housed in c. Therefore, the optical isolator 82 included in the optical isolator element 8 is set to the outer surface 3d of the wall 3a.
Can be placed close to. Therefore, it is more suitable to follow the temperature of the optical isolator 82 so as to be equal to the temperature of the light emitting element 6 provided on the substrate 3.
Here, the through hole 3c is formed to have an inner diameter larger than the outer diameter of the optical lens element 7 so that the optical lens element 7 can be accommodated therein. The other end surface 71b of the optical lens holder 71 of the optical lens element 7 is fixed to the optical isolator holder 81 of the optical isolator element 8.
In this case, only the other end surface 71b of the optical lens holder 71 needs to be precisely polished, and the positions of the optical lens element 7 and the optical isolator element 8 are adjusted to each other along the optical axis A so that the other end surface 71b becomes the end surface 81a. The optical lens holder 71 and the optical isolator holder 81 can be welded and fixed by the YAG laser in the abutting state. And the end face 8
After the optical lens element 7 is aligned to the optimum position for condensing the emitted light of the semiconductor light emitting element 6 with 1a in contact with the outer surface 3d of the wall portion 3a, the YAG laser is used to align the light with the outer surface 3d. The isolator holder 81 can be fixed by welding.

Further, in the light emitting module 1 of the second embodiment, the optical isolator 82 is composed of a magnetic garnet crystal having a Faraday effect, a permanent magnet for applying a predetermined magnetic field to the magnetic garnet crystal, and a polarizing element. ,
When the temperature of the optical isolator 82 is 25 ° C, 1590n
It exhibits the maximum isolation characteristic in the wavelength band of m. FIG. 6 shows the isolation characteristic with respect to the temperature of the optical isolator 82. In FIG. 6, a is 1590n
m is the isolation characteristic for light in the wavelength band, b is the isolation characteristic for light in the 1610 nm wavelength band, and c is the isolation characteristic for light in the 1570 nm wavelength band. Then, as shown in FIG. 6, b is 0.
30dB or more at ℃ ~ 27.5 ℃, c is 22.5 ℃
It is 30 dB or more at -50 ° C. When the environmental temperature in which the light emitting module 1 is placed changes in the range of 0 ° C to 50 ° C,
In the light emitting module 1 of the second embodiment, when the semiconductor light emitting device 6 is controlled to the temperature of 25 ± 1 ° C. by the Peltier device 2, the isolator 82 is controlled to the temperature within 25 ± 2.5 ° C. On the other hand, in the conventional optical module 1 shown in FIG. 4, which is a comparative example of the second embodiment,
The semiconductor light emitting device 6 is moved to 25 ± 1 ° C. by the Peltier device 2.
When controlled to a constant temperature of
It was within 5 ± 4 ° C. Therefore, according to the light emitting module 1 of the second embodiment, from the optical fiber 15 to the window 20b.
A blocking characteristic of 30 dB or more is realized for broadband light of 1570 nm to 1610 nm propagating in the other direction, which is the direction of the semiconductor light emitting element 6 via the. As shown in the light emitting module 1 of the second embodiment, the ambient temperature is 0 ° C to 50 ° C.
Provided is the light emitting module 1 which is stable in operation with respect to light in the wavelength band of 1570 nm to 1610 nm, which is a wide band even when the temperature changes with temperature. The optical isolator holder 81
It is more suitable to make the temperature of the optical isolator 82 follow so that it becomes equal to the temperature of the semiconductor light emitting element 6 by forming a material containing a material having a higher thermal conductivity than the optical lens holder 71. In this case, for example, the optical lens holder 8
1 is made of SUS, and the optical isolator holder 82 is SF.
It can be 20T.

As described in detail above, the operation of the light emitting element is stable by being configured in a small package which is easy to manufacture and the optical isolator which follows the temperature of the light emitting element without being influenced by the ambient temperature. The light emitting module is provided.

It is obvious and within the scope of the present invention that modifications that the person skilled in the art can easily make the above-described embodiments without departing from the scope of the present invention are within the scope of the present invention. To claim that.

For example, in the above description, the light emitting element 6 is described as the semiconductor optical element 6, but the semiconductor optical element 6 is used.
Can be the semiconductor laser device 6, and can also be the DFB laser device 6. Further, the semiconductor laser element 6 has a wavelength band of emitted light of 1480 μm.
It is also possible to use m as the excitation light source of the optical amplifier.

Further, FIG. 3 is a sectional structural view of the light emitting module 1 having a structure in which the second optical lens element 9 is inserted between the package outer surface 20c and the ferrule holder 13 in FIG. As shown in FIG. 3, the light emitting module 1 has a second
The optical lens element 9 may be included. The second optical lens element 9 includes a second optical lens 91 and a second optical lens holder 92. In this case, the optical lens element 7
The optical lens 71 may be a collimating optical lens that condenses the light emitted from the light emitting element 6 into parallel light, and the second optical lens 91 may be a condensing optical lens that condenses the collimated light onto the optical fiber 15. . With the above configuration, in the light emitting module 1, the light collecting point position where the light emitted from the light emitting element 6 is condensed in the optimum state with respect to the incidence of the optical fiber 15 is determined by the second optical lens element. It becomes possible to modify appropriately by 9 and therefore, the sub-assembly 3
The accuracy of mounting 0 on the package bottom surface 20a of the package 20 can be relaxed.

[0045]

In the light emitting module according to the present invention, since the optical isolator element is directly fixed to the substrate, the heat capacity of the portion interposed between the light emitting element and the optical isolator element is small and equal to the temperature of the light emitting element. It is suitable for making the temperature of the optical isolator follow. Therefore, the operation of the light emitting module is stabilized, and the light in the predetermined wavelength band emitted from the light emitting element can be efficiently transmitted through the optical isolator element to the optical fiber side.

[Brief description of drawings]

FIG. 1 is a cross-sectional configuration diagram of a light emitting module 1 according to an embodiment of the present invention.

FIG. 2A is a sectional configuration diagram of a subassembly 30. FIG. 2B is an exploded sectional configuration diagram in which the optical lens element 7 and the optical isolator element 8 of the subassembly 30 are separated from the substrate 3.

3 is a view showing a second portion between the package outer surface 20c of the package 20 and the ferrule holder 13 in FIG.
3 is a cross-sectional configuration diagram of a light emitting module 1 having a configuration in which the optical lens element 9 of FIG.

FIG. 4 is a side sectional view showing a structure of a light emitting module according to a conventional technique.

FIG. 5A is a cross-sectional configuration diagram of a subassembly 30 of the light emitting module 1 according to the second embodiment. Further, FIG. 5B is an exploded cross-sectional configuration diagram in which the optical lens element 7 and the optical isolator element 8 of the subassembly 30 are separated from the substrate 3.

6 is an isolation characteristic with respect to temperature of the optical isolator 82. FIG.

[Explanation of symbols]

1 ... Light emitting module 2 ... Temperature control element (Peltier element) 3 ... Substrate 4 ... Photodiode 4a ... Photodiode carrier 5 ... Chip carrier 6 ... Light emitting element (semiconductor light emitting element) 7 ... Optical lens element 8 ... Optical isolator element 9 ... Second optical lens element 11 ... Thermistor 13 ... Ferrule holder 14 ... Ferrule 15 ... Optical fiber 20 ... Package 20a ... low surface of package 20b ... window 20c ... Package outer surface 30 ... Sub-assembly 71 ... Optical lens holder 72 ... Optical lens 81 ... Optical isolator holder 82 ... Optical isolator 91 ... Second optical lens 92 ... Second optical lens holder

Claims (3)

[Claims] 1. A substrate, a sub-assembly including a light-emitting element, an optical lens element, and an optical isolator element provided on the substrate, a temperature control element on which the sub-assembly is mounted, and a bottom surface on which the temperature control element is mounted. A package including the temperature control element mounted on the bottom surface and included therein, and an optical fiber for propagating outgoing light of the light emitting element for propagation, wherein the optical isolator element is directly fixed to the substrate, A light emitting module characterized in that 2. The optical lens element comprises an optical lens that collects light emitted from the light emitting element and makes it enter the optical isolator element, and an optical lens holder that holds the optical lens and is fixed to a substrate. The optical isolator element includes an optical isolator that passes light in a predetermined wavelength band only in one direction and an optical isolator holder that holds the optical isolator and fixes it to a substrate, and the optical isolator holder is the optical lens. The light emitting module according to claim 1, wherein the light emitting module is formed by including a material having a thermal conductivity higher than that of the holder. 3. The light emitting module according to claim 1, wherein the optical fiber is provided outside the package.