CN111708131A

CN111708131A - Light emitting module and optical module

Info

Publication number: CN111708131A
Application number: CN202010576701.5A
Authority: CN
Inventors: 刘弘扬; 朱虎; 杜书剑; 郭燕玲; 周日凯; 付永安
Original assignee: Accelink Technologies Co Ltd
Current assignee: Accelink Technologies Co Ltd
Priority date: 2020-06-22
Filing date: 2020-06-22
Publication date: 2020-09-25
Also published as: WO2021258661A1

Abstract

The embodiment of the application discloses light emission subassembly and optical module includes: a substrate; sealing the cover plate; a laser; a lens; the array waveguide grating chip comprises a waveguide input end and a front optical waveguide output end, wherein the waveguide input end, a lens and a laser are in optical coupling connection; the contact pin assembly comprises an optical fiber array head, a first optical fiber, an online optical isolator, an adapter assembly and a second optical fiber, wherein the optical fiber array head penetrates through the sealing cover plate to be in optical coupling connection with the output end of the front optical waveguide, the optical fiber array head is in coupling connection with the online optical isolator, and the online optical isolator is in coupling connection with the adapter assembly; the online optical isolator is arranged outside the closed cavity. The light emitting component and the optical module have the advantage of saving space.

Description

Light emitting module and optical module

Technical Field

The application relates to the field of optoelectronic device packaging, in particular to a light emitting assembly and an optical module.

Background

In recent years, rapid development of the optical communication technology industry has promoted the evolution of the optical device industry toward high speed, miniaturization, and integration. The design scheme of the package-on-package is mostly adopted for the traditional 40G/100G optical device for packaging QSFP +/QSFP28 (namely, a four-channel SFP interface, 28 is a series model), and due to the high material cost of the package-on-package and the power change caused by the laser welding process which must be adopted, the strict requirements of the subsequent high-speed packaging form on cost, volume and performance cannot be met gradually.

At present, the isolator of most light emission subassembly is all built-in the main part, has increased the coupling optical path length of main part on the one hand, and on the other hand has also taken up the space in the main part, and then has compressed the overall arrangement space of other key components and parts.

Disclosure of Invention

In view of the above, embodiments of the present disclosure are directed to providing a light emitting module and an optical module, which can save space.

In order to achieve the above purpose, the technical solution of the embodiment of the present application is implemented as follows:

a light emitting assembly comprising: a substrate; sealing the cover plate; the sealing cover plate is covered on the substrate to form a closed cavity; a laser housed within the enclosed cavity; the laser comprises a laser chip and a substrate arranged on the substrate, wherein the laser chip is arranged on the substrate; a lens contained within the enclosed cavity; the array waveguide grating chip is accommodated in the closed cavity and comprises a waveguide input end and a front optical waveguide output end, and the waveguide input end, the lens and the laser are in optical coupling connection; the pin assembly comprises an optical fiber array head, a first optical fiber, an online optical isolator, an adapter assembly and a second optical fiber, the optical fiber array head penetrates through a sealing cover plate to be in optical coupling connection with the output end of the front optical waveguide, the optical fiber array head is in coupling connection with the online optical isolator through the first optical fiber, and the online optical isolator is in coupling connection with the adapter assembly through the second optical fiber; the online optical isolator is arranged outside the closed cavity.

Furthermore, the online optical isolator comprises a left collimator, a left wedge angle sheet, a magnetic ring, a Faraday rotator, a right wedge angle sheet, a right collimator and a glass sleeve; the left wedge angle piece, the Faraday rotator and the right wedge angle piece are sequentially arranged in the magnetic ring; the left collimator, the magnetic ring and the right collimator are sequentially sleeved in the glass sleeve, and the optical fiber array head is connected with the left collimator through the first optical fiber in a coupling mode.

Furthermore, the adapter component comprises an optical fiber adapter, a ceramic ferrule, a ceramic sleeve and a metal ring, wherein the metal ring and the ceramic sleeve are sequentially sleeved in the optical fiber adapter along the axial direction of the optical fiber adapter, the ceramic ferrule penetrates through the metal ring and extends into the ceramic sleeve, and the ceramic ferrule is coupled with the right collimator through the second optical fiber.

Furthermore, the optical fiber array head comprises an upper cover plate, a lower base plate and a fixing part, wherein a V-shaped groove is formed in the lower base plate, the upper cover plate covers the V-shaped groove, and the fixing part is arranged in the V-shaped groove and used for fixing the end part of the first optical fiber extending into the V-shaped groove.

Further, the first optical fiber and/or the second optical fiber adopt a fiber coiling process.

Further, the light emitting assembly comprises a first backlight chip accommodated in the closed cavity, the arrayed waveguide grating chip comprises a backlight waveguide output end, and the first backlight chip is in optical coupling connection with the backlight waveguide output end.

Further, the number of the laser chips, the number of the waveguide input ends, and the number of the backlight waveguide output ends are equal.

Furthermore, the backlight waveguide output end and the front optical waveguide output end are both arranged on one side of the arrayed waveguide grating chip far away from the laser; the waveguide input end is arranged on one side, close to the laser, of the arrayed waveguide grating chip, and the first backlight chip is arranged on one side, far away from the laser, of the closed cavity.

Further, the light emitting assembly comprises a second backlight chip accommodated in the closed cavity, the laser chip comprises a backlight output end, and the second backlight chip is in optical coupling connection with the backlight output end.

A light module, comprising: the light emitting module comprises a printed circuit board assembly, a light receiving module and the light emitting module, wherein the light emitting module and the light receiving module are arranged on the printed circuit board assembly.

The optical transmission assembly and the optical module are arranged outside the closed cavity body through the online optical isolator, and are connected by adopting optical fibers in a pin inserting assembly mode, so that the overall size is reduced; the space in the closed cavity can be used for arranging other key components, a larger layout space is provided for circuit design, the optical coupling difficulty of the laser, the lens and the array waveguide grating chip in the closed cavity is reduced, and the process difficulty is reduced. In addition, the front optical waveguide output end of the arrayed waveguide grating chip is connected with the adapter component through the optical fiber array head, compared with the laser welding technology of the front optical waveguide output end and the adapter component in the prior art, the problem of optical power deviation after welding is avoided, and the manufacturing cost is reduced.

Drawings

Fig. 1 is a schematic structural diagram of a light emitting module according to an embodiment of the present disclosure;

FIG. 2 is a top view of FIG. 1 with the sealing cover plate omitted;

fig. 3 is a schematic structural diagram of a pin assembly according to an embodiment of the present disclosure;

FIG. 4 is a schematic cross-sectional view of a fiber array head according to an embodiment of the present application;

FIG. 5 is a schematic diagram of the internal structure of an in-line optical isolator according to an embodiment of the present application;

FIG. 6 is a schematic diagram of the internal structure of an adapter assembly according to an embodiment of the present application;

FIG. 7 is a schematic structural diagram of an arrayed waveguide grating chip according to an embodiment of the present application;

FIG. 8 is a view taken along line A of FIG. 7;

fig. 9 is a schematic structural view of a light emitting module according to another embodiment of the present application, in which a sealing cover plate is omitted.

Detailed Description

It should be noted that, in the case of conflict, the technical features in the examples and examples of the present application may be combined with each other, and the detailed description in the specific embodiments should be interpreted as an explanation of the present application and should not be construed as an improper limitation of the present application.

In the description of the embodiments of the present application, the "up", "down", "left", "right", "front", "back" orientation or positional relationship is based on the orientation or positional relationship shown in fig. 1, it is to be understood that these orientation terms are merely for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be considered as limiting the present application.

As shown in fig. 1 to 9, a light emitting module includes a substrate 2, a sealing cover plate 7, a laser 1, a lens 3, an arrayed waveguide grating chip 5, and a pin module 6.

The substrate 2 is made of aluminum nitride or tungsten copper alloy, and is used for heat conduction and fixing other components.

The sealing cover plate 7 is covered on the substrate 2 to form a closed cavity 71; the closed cavity 71 is used for accommodating other component structures, and has protection and dustproof effects.

The laser 1 is accommodated in the closed cavity 71; the laser 1 comprises a laser chip 11 and a base plate 12 arranged on the substrate 2, wherein the base plate 12 can be fixed with the substrate 2 by adopting conductive silver adhesive, the laser chip 11 is used for emitting optical signals with specified wavelength, and the laser chip 11 is arranged on the base plate 12; the number of the laser chips 11 is one or more. Types of laser chips 11 include, but are not limited to, DFB chips, FB chips, VCSEL chips, EML chips; wavelength types include, but are not limited to 850nm, 1310nm, 1550 nm.

The lens 3 is accommodated in the closed cavity 71; the lens 3 is made of glass or silicon; a lens 3 is disposed on the substrate 2 to diverge or converge the optical signal; and the substrate 2 may be provided with a positioning groove (not shown) at a position corresponding to the lens 3 to facilitate the lens 3 to be inserted into the positioning.

The array waveguide grating chip 5 is accommodated in the closed cavity 71, and the array waveguide grating chip 5 can be attached to the substrate 2 through conductive silver paste so as to realize heat dissipation through the substrate 2 in a working state. The arrayed waveguide grating chip 5 comprises a waveguide input end 51 and a front optical waveguide output end 52, wherein the waveguide input end 51, the lens 3 and the laser 1 are optically coupled. Specifically, the optical signal emitted from the laser chip 11, after passing through the lens 3, enters the arrayed waveguide grating chip 5 from the waveguide input end 51 and is processed.

The ferrule assembly 6 includes a fiber array head 61, a first optical fiber 62, an in-line optical isolator 63, an adapter assembly 64, and a second optical fiber 65.

The optical fiber array head 61 penetrates through the sealing cover plate 7 to be in optical coupling connection with the front optical waveguide output end 52, and after optical signals emitted by the laser 1 are processed by the arrayed waveguide grating chip 5, most of the optical signals are output from the front optical waveguide output end 52 and enter the optical fiber array head 61; the optical fiber array head 61 is coupled with the online optical isolator 63 through the first optical fiber 62, and the online optical isolator 63 allows an optical signal from one side of the optical fiber array head 61 to pass through, so that an external optical signal is prevented from entering the arrayed waveguide grating chip 5 to interfere; the in-line optical isolator 63 is coupled with the adapter assembly 64 through a second optical fiber 65; the optical signal enters the fiber array head 61, passes through the in-line optical isolator 63, and then exits the adapter assembly 64 for subsequent processing.

The first optical fiber 62 and the second optical fiber 65 are optical fibers with protective layers, and the lengths thereof can be flexibly designed according to the actual requirements of the optical device.

The online optical isolator 63 is arranged outside the closed cavity 71 and is connected by adopting an optical fiber in the form of a pin inserting assembly 6, so that the whole volume is reduced; the space in the closed cavity 71 can be used for arranging other key components, a larger layout space is provided for circuit design, the optical coupling difficulty of the laser 1, the lens 3 and the array waveguide grating chip 5 in the closed cavity 71 is reduced, and the process difficulty is reduced. In addition, the front optical waveguide output end 52 of the arrayed waveguide grating chip 5 and the adapter component 64 are connected through the optical fiber array head 61, compared with the laser welding technology of the front optical waveguide output end 52 and the adapter component 64 in the prior art, the problem of optical power deviation after welding is avoided, and the manufacturing cost is reduced.

1-3, and 5, in-line optical isolator 63 includes a left collimator 631, a left wedge 632, a magnet ring 633, a Faraday rotator 634, a right wedge 635, a right collimator 636, and a glass sleeve 637. The left wedge angle piece 632, the Faraday rotator 634 and the right wedge angle piece 635 are sequentially arranged in the magnetic ring 633; faraday rotator 634 has non-reciprocity and is effective in isolating the optical signal that suppresses the echo reflections. After the left collimator 631, the magnetic ring 633 and the right collimator 636 are aligned by means of optical coupling, they are sequentially sleeved in the glass sleeve 637, and the connection may be by gluing. The fiber array head 61 and the left collimator 631 are coupled through the first fiber 62, and the connection part can be fixed and buffered by soft glue to prevent damage in daily use.

1-3, and 6, the adapter assembly 64 includes a fiber optic adapter 641, a ferrule 642, a ferrule 643, and a ferrule 644. In the axial direction of the optical fiber adapter 641, the metal ring 644 and the ceramic sleeve 643 are sequentially sleeved in the optical fiber adapter 641, the optical fiber adapter 641 may be made of metal, and the optical fiber adapter 641 and the metal ring 644 may be connected by interference fit or bonded by glue. The ferrule 642 penetrates through the metal ring 644 and extends into the ferrule 643 to complete fixation, the ferrule 642 and the right collimator 636 are coupled and connected through the second optical fiber 65, and the connection part can be fixed and buffered by soft glue to prevent damage in daily use.

The ferrule 642 may be a single-mode ferrule or a multi-mode ferrule, so that the corresponding second optical fiber 65 may be a single-mode fiber or a multi-mode fiber, and the specific model needs to be configured according to the usage requirement of the optical device.

In one possible embodiment, as shown in fig. 1 to 4, the fiber array head 61 includes an upper cover plate 611, a lower base plate 614 and a fixing portion 612, and both the upper cover plate 611 and the lower base plate 614 can be made of glass.

The lower plate 614 has a V-groove 614a formed thereon to facilitate the assembly of the end of the second optical fiber 65 extending into the ferrule 642, the upper cover 611 covers the V-groove 614a, and the fixing portion 612 may be a curing glue filled in the V-groove 614a for fixing the end of the first optical fiber 62 extending into the V-groove 614 a.

In one possible embodiment, the first optical fiber 62 and/or the second optical fiber 65 employ a fiber coiling process to save volume.

In the prior art, a backlight chip is generally placed behind a laser, but the backlight chip can only be used for monitoring the output power of an optical signal of the laser, but cannot monitor the output optical power of the whole optical signal, so that the difficulty of adjusting the power of the arrayed waveguide grating chip and the laser by an external control terminal is increased.

In one possible embodiment, as shown in fig. 1, fig. 2, and fig. 7 to fig. 9, the light emitting assembly includes a first backlight chip 4 accommodated in a closed cavity 71, the first backlight chip 4 is fixed on the substrate 2 by conductive silver paste, the arrayed waveguide grating chip 5 includes a backlight waveguide output end 53, and the first backlight chip 4 is optically coupled to the backlight waveguide output end 53. The optical signal entering from the waveguide input 51 is processed by the arrayed waveguide grating chip 5, and a part of the optical signal is output from the front optical waveguide output 52, and another part of the optical signal is output from the backlight waveguide output 53.

The first backlight chip 4 may include one or more optical receiver chips (not shown) that can receive optical signals of a specified wavelength range and a backlight substrate (not shown); the first backlight chip 4 receives the backlight from the arrayed waveguide grating chip 5, thereby accurately monitoring the output power of the arrayed waveguide grating chip 5.

Specifically, the optical signal of 100 emitted by the laser 1 is converged by the lens 3, enters the arrayed waveguide grating chip 5 from the waveguide input end 51, and the optical signal with the ratio of 90 is output from the front optical waveguide output end 52, enters the pin assembly 6, and is transmitted to a subsequent device for wavelength division multiplexing processing; the optical signal of the remaining proportion 10 is output from the backlight waveguide output end 53 into the first backlight chip 4, so as to realize monitoring. By detecting the optical signal output by the backlight waveguide output end 53, the output optical power can be monitored after the proportion is converted, thereby facilitating the difficulty of power regulation of the array waveguide grating chip 5 by an external control end; and the optical signal output by the backlight waveguide output end 53 directly feeds back the output of the whole optical path, the whole optical path comprises the optical paths from the laser 1, the lens 3 and the arrayed waveguide grating chip 5, one of the optical paths changes, the optical signal output by the backlight waveguide output end 53 can be fed back to the first backlight chip 4 in time, that is, the feedback can be used as the whole optical path to change, finally, the function of monitoring the whole output power and the optical path change by the first backlight chip 4 is realized, and the difficulty of debugging and measuring is greatly reduced.

In one possible embodiment, as shown in fig. 1, fig. 2, and fig. 7 to fig. 9, the number of the backlight waveguide output ends 53 may be one or more, the number of the front optical waveguide output ends 52 is one, and the number of the laser chips 11, the number of the waveguide input ends 51, and the number of the backlight waveguide output ends 53 are equal, and the three correspond to one another, so as to facilitate the first backlight chip 4 to effectively monitor the output power of each corresponding laser chip 11 and the corresponding arrayed waveguide grating chip 5.

Specifically, as shown in fig. 2 and fig. 9, the laser 1 has laser chips 11 emitting four different wavelengths, and the laser chips 11 are arranged at equal intervals, and actually, the laser chips 11 may be arranged at equal intervals or arranged at unequal intervals, and the specific implementation form performs appropriate adjustment of the intervals according to the characteristics of the optical path.

The waveguide input port 51 includes four waveguide input ports respectively corresponding to the four laser chips 11 of the laser 1, and the pitch is consistent with that of the laser chips 11.

The backlight waveguide output end 53 includes four backlight waveguide output ports respectively corresponding to the four backlight chips of the first backlight chip 4, and the pitch is consistent with that of the backlight chips.

In one possible embodiment, as shown in fig. 1, fig. 2, and fig. 7 to fig. 9, the backlight waveguide output end 53 and the front optical waveguide output end 52 are both disposed on the side of the arrayed waveguide grating chip 5 away from the laser 1; the waveguide input end 51 is arranged on the side of the arrayed waveguide grating chip 5 close to the laser 1.

The first backlight chip 4 is arranged on one side of the closed cavity 71 far away from the laser 1, and the online optical isolator 63 is fully utilized to move out of the space outside the closed cavity 71 to arrange the first backlight chip 4, so that the light emitting component is compact in structure and beneficial to volume reduction.

In one possible embodiment, as shown in fig. 9, the light emitting assembly includes a second backlight chip 8 accommodated in the closed cavity 71, the laser chip 11 includes a backlight output end 111, and the second backlight chip 8 is optically coupled to the backlight output end 111. The output power of the optical signal of the laser 1 is monitored in real time by the second backlight chip 8.

It is to be understood that the second backlight chip 8 and the first backlight chip 4 can be used either individually or in combination. Under the condition of combined use, aiming at the whole optical path, if the power of the optical signal monitored by the first backlight chip 4 is abnormal and the power of the optical signal monitored by the second backlight chip 8 is normal, the output power of the optical signal of the laser 1 is normal, the problem of the array waveguide grating chip 5 or the lens 3 can be conveniently judged, and the specific judgment is further carried out by the modes of disassembling and assembling the lens 3 or observing cracks and the like; on the contrary, if the power of the optical signal monitored by the first backlight chip 4 is normal and the power of the optical signal monitored by the second backlight chip 8 is abnormal, it can be conveniently determined that the laser 1 has a problem, and the difficulty of debugging and testing is greatly reduced.

In one possible embodiment, as shown in fig. 1, 2, 7 and 8, the arrayed waveguide grating chip 5 is formed with an oblique angle B on both sides, which may be selected to be 1-20 ° in general to facilitate the subsequent coupling.

A light module, comprising: the light emitting component and the light receiving component are arranged on the printed circuit board component. The printed circuit board assembly comprises a printed circuit board, a heat dissipation carrier, a device electrical interface and a golden finger; the substrate 2 of the light emitting component and the heat dissipation carrier realize the functions of fixing and heat conduction through heat conduction silver colloid, and the electrical interface of the device and the laser 1 in the light emitting component are electrically connected in a gold wire mode.

The various embodiments/implementations provided herein may be combined with each other without contradiction.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A light emitting assembly, comprising:

a substrate (2);

a sealing cover plate (7); the sealing cover plate (7) is covered on the substrate (2) to form a closed cavity (71);

a laser (1) housed within the closed cavity (71); the laser (1) comprises a laser chip (11) and a substrate (12) arranged on the substrate (2), wherein the laser chip (11) is arranged on the substrate (12);

a lens (3) housed within the closed cavity (71);

an arrayed waveguide grating chip (5) accommodated in the closed cavity (71), wherein the arrayed waveguide grating chip (5) comprises a waveguide input end (51) and a front optical waveguide output end (52), and the waveguide input end (51), the lens (3) and the laser (1) are optically coupled;

and a pin assembly (6), wherein the pin assembly (6) comprises a fiber array head (61), a first optical fiber (62), an online optical isolator (63), an adapter assembly (64) and a second optical fiber (65), the fiber array head (61) is optically coupled with the front optical waveguide output end (52) through a sealing cover plate (7), the fiber array head (61) and the online optical isolator (63) are coupled through the first optical fiber (62), and the online optical isolator (63) and the adapter optical isolator assembly (64) are coupled through the second optical fiber (65); the online optical isolator (63) is arranged outside the closed cavity (71).

2. The light emitting assembly of claim 1, wherein: the online optical isolator (63) comprises a left collimator (631), a left wedge angle sheet (632), a magnetic ring (633), a Faraday rotator (634), a right wedge angle sheet (635), a right collimator (636) and a glass sleeve (637); the left wedge angle piece (632), the Faraday rotator (634) and the right wedge angle piece (635) are sequentially arranged in the magnetic ring (633); the left collimator (631), the magnetic ring (633) and the right collimator (636) are sequentially sleeved in the glass sleeve (637), and the optical fiber array head (61) is coupled with the left collimator (631) through the first optical fiber (62).

3. The light emitting assembly of claim 2, wherein: the adapter assembly (64) comprises a fiber optic adapter (641), a ferrule (642), a ferrule (643) and a metal ring (644), wherein the metal ring (644) and the ferrule (643) are sequentially sleeved in the fiber optic adapter (641) along the axial direction of the fiber optic adapter (641), the ferrule (642) penetrates through the metal ring (644) and extends into the ferrule (643), and the ferrule (642) and the right collimator (636) are coupled and connected through the second optical fiber (65).

4. The light emitting assembly of claim 1, wherein: the optical fiber array head (61) comprises an upper cover plate (611), a lower base plate (614) and a fixing part (612), wherein a V-shaped groove (614a) is formed on the lower base plate (614), the upper cover plate (611) covers the V-shaped groove (614a), and the fixing part (612) is arranged in the V-shaped groove (614a) and used for fixing the end part of the first optical fiber (62) extending into the V-shaped groove (614 a).

5. The light emitting assembly of claim 1, wherein: the first optical fiber (62) and/or the second optical fiber (65) adopt a fiber coiling process.

6. The light emitting assembly of claim 1, wherein: the light emitting component comprises a first backlight chip (4) accommodated in the closed cavity (71), the arrayed waveguide grating chip (5) comprises a backlight waveguide output end (53), and the first backlight chip (4) is in optical coupling connection with the backlight waveguide output end (53).

7. The light emitting assembly of claim 6, wherein: the number of laser chips (11), the number of waveguide inputs (51), and the number of backlight waveguide outputs (53) are equal.

8. The light emitting assembly of claim 6, wherein: the backlight waveguide output end (53) and the front optical waveguide output end (52) are both arranged on one side of the arrayed waveguide grating chip (5) far away from the laser (1); the waveguide input end (51) is arranged on one side, close to the laser (1), of the arrayed waveguide grating chip (5), and the first backlight chip (4) is arranged on one side, far away from the laser (1), of the closed cavity (71).

9. The light emitting assembly of claim 1 or 6, wherein: the light emitting component comprises a second backlight chip (8) accommodated in the closed cavity (71), the laser chip (11) comprises a backlight output end (111), and the second backlight chip (8) is in optical coupling connection with the backlight output end (111).

10. A light module, characterized in that the light module comprises: a printed circuit board assembly, a light receiving assembly and a light emitting assembly as claimed in any one of claims 5 to 9, the light emitting assembly and the light receiving assembly being provided on the printed circuit board assembly.