Optical transmission assembly and external laser source pluggable module

Abstract

This disclosure provides an optical transmission assembly comprising a metal substrate, a cover, a laser submount, a laser chip, a first collimating lens, and a passive optical device. The cover has an annular bottom surface. The annular bottom surface is welded to the metal substrate so that the cover and the metal substrate together form a hermetically sealed space. The laser submount is coupled to the metal substrate and located within the hermetically sealed space. The laser submount has a first bearing surface and a second bearing surface facing away from the metal substrate. The first bearing surface is closer to the metal substrate than the second bearing surface. The laser chip is coupled to the second bearing surface. The first collimating lens is coupled to the first bearing surface. The passive optical device is coupled to the metal substrate and located outside the hermetically sealed space. The laser chip is optically coupled to the passive optical device through the first collimating lens.

Description

Optical transmission components and external laser pluggable optical modules OPTICAL TRANSMISSION ASSEMBLY AND EXTERNAL LASER SOURCE PLUGGABLE MODULE Technical Field

[0001] This disclosure relates to an optical transmission component and an external laser pluggable optical module. Prior Technology

[0002] Optical modules can transmit and / or receive optical signals for applications such as, but not limited to, data centers, cable TV, and fiber-to-the-home (FTTH). Using optical modules for transmission can provide higher transmission rates and signal bandwidth over longer transmission distances. To promote the compatibility of global optical internet products and reduce maintenance burdens, organizations such as the Multi-Source Agreement (MSA), the Institute of Electrical and Electronics Engineers (IEEE), and the Optical Internetworking Forum (OIF) have developed several form factors suitable for different signal transmission rates. These form factors include, but are not limited to, XFP, SFP, QSFP (Quad Small Form Factor Pluggable), QSFP-DD (Double Density), OSFP (Octal Small Form Factor Pluggable), ELSFP (External Laser Small Form Factor Pluggable), and CPO (Co-Packaged Optics).

[0003] Existing optical modules face challenges such as optical power, space management, thermal management, insertion loss, and manufacturing yield. Summary of the Invention

[0004] This disclosure provides an optical transmission component and an external laser pluggable optical module, which helps to solve the problems of existing optical modules.

[0005] This disclosure presents an embodiment of an optical transmission assembly comprising a metal base, a cover, a laser sub-mount, a laser chip, a first collimating lens, and a passive optical device. The cover has an annular bottom surface. The annular bottom surface is welded to the metal base so that the cover and the metal base together form a hermetically sealed space. The laser sub-mount is coupled to the metal base and located within the hermetically sealed space. The laser sub-mount has a first bearing surface and a second bearing surface facing away from the metal base. The first bearing surface is closer to the metal base than the second bearing surface. The laser chip is coupled to the second bearing surface. The first collimating lens is coupled to the first bearing surface. The passive optical device is coupled to the metal base and located outside the hermetically sealed space. The laser chip is optically coupled to the passive optical device through the first collimating lens.

[0006] Another embodiment of this disclosure discloses an externally pluggable laser optical module comprising a housing, a circuit board assembly, a metal base, a cover, a laser secondary mount, a laser chip, a first collimating lens, and passive optical devices. The circuit board assembly is located within the housing. The metal base is located within the housing and coupled to the circuit board assembly. The cover has an annular bottom surface. The annular bottom surface is welded to the metal base so that the cover and the metal base together form a hermetically sealed space. The laser secondary mount is coupled to the metal base and located within the hermetically sealed space. The laser secondary mount has a first bearing surface and a second bearing surface facing away from the metal base. The first bearing surface is closer to the metal base than the second bearing surface. The laser chip is coupled to the second bearing surface. The first collimating lens is coupled to the first bearing surface. The passive optical devices are coupled to the metal base and located outside the hermetically sealed space. The laser chip is optically coupled to the passive optical devices through the first collimating lens.

[0007] According to the optical transmission component and external laser pluggable optical module disclosed in this embodiment, since the laser chip and the first collimating lens are coupled to the same laser submount, it can be ensured that the laser chip and the first collimating lens expand or contract synchronously when the temperature changes, reducing the thermal drift of their relative positions, suppressing optical path offset, and achieving high optical coupling efficiency.

[0008] The foregoing description of the contents of this disclosure and the following description of the implementation methods are intended to demonstrate and explain the spirit and principles of this disclosure, and to provide a further explanation of the scope of the patent application disclosed herein. Simple Explanation of the Diagram

[0009] Figure 1 is a perspective view of an optical transmission component according to a first embodiment of the present disclosure. Figure 2 is a side view of the optical transmission component in Figure 1. Figure 3 is a bottom view of the cover of the optical transmission component in Figure 1. Figure 4 is a side view of the cover in Figure 3. Figure 5 is a perspective view of the optical transmission component in Figure 1 with the top cover removed. Figure 6 is a top view of the optical transmission component in Figure 5. Figure 7 is a cross-sectional view of the optical transmission component in Figure 5. Figure 8 is a cross-sectional view of an optical transmission component according to a second embodiment of the present disclosure. Figure 9 is a cross-sectional view of an optical transmission component according to a third embodiment of the present disclosure. Figure 10 is a cross-sectional view of an optical transmission component according to a fourth embodiment of the present disclosure. Figure 11 is a perspective view of an external laser pluggable optical module according to a fifth embodiment of the present disclosure. Figure 12 is a schematic diagram of some components of the external laser pluggable optical module in Figure 11. Figure 13 is a schematic diagram of an optoelectronic device according to an embodiment of the present disclosure. Implementation

[0010] The following disclosure describes the principles of this disclosure and its exemplary embodiments, and may be illustrated with drawings where necessary. However, any description and drawings are not an exhaustive list of all embodiments of this disclosure, nor are they intended to limit this disclosure to a specific particular form. Those skilled in the art will understand from the disclosure that many modifications and variations are possible, and thus various implementations can be reasonably derived.

[0011] As the optical communication industry develops towards higher speeds and larger capacities, the demand for laser output power continues to increase, leading to a significant increase in the power consumption of optical modules. To reduce the overall power consumption of optical modules, it is necessary to further improve the photoelectric conversion efficiency and optical coupling efficiency of lasers. To meet the requirements of long-term device lifespan and reliability, optical modules must adopt a hermetically sealed BOX packaging. However, known BOX packaging structures have externally soldered adapters that need to be mated with ceramic ferrules. This type of BOX packaging structure introduces additional insertion loss during optical mating, which is detrimental to improving optical coupling efficiency and makes it difficult to maintain the stability of the optical signal polarization state. In addition, the adapter in this type of BOX packaging structure is only fixed through side soldering, and the bottom of the adapter is suspended, making the stability of the packaging structure highly dependent on the strength of a few solder points. At the same time, the pigtail exerts a certain force on the adapter when it is coiled or fixed. Since the suspended section of the adapter forms a lever arm, the force is amplified when it is transmitted to the solder point. In mechanical vibration and shock tests, if there are minor defects in the solder points, it may cause the solder joints to loosen, resulting in increased insertion loss or deterioration of return loss.

[0012] Furthermore, temperature variations during the welding process in the BOX hermetic assembly can cause a shift in the relative positions of optical components. For high-speed optical modules, the resulting decrease in optical coupling efficiency due to this positional shift has become significant.

[0013] According to one embodiment of the present disclosure, since the laser chip and the first collimating lens are coupled to the same laser submount, it can be ensured that the laser chip and the first collimating lens expand or contract synchronously when the temperature changes, thereby reducing thermal drift of their relative positions, suppressing optical path offset, and achieving high optical coupling efficiency.

[0014] Those skilled in the art can reasonably combine and configure the following disclosed technical features to achieve the corresponding technical effects.

[0015] The terms "coupled" or "coupled" refer to any connection, link, or similar relationship, and "optical coupling" or "optical linking" refers to the transfer of light from one element to another. Unless otherwise stated, elements that are coupled or linked to each other do not need to be directly connected to each other and may be separated by intermediate elements.

[0016] The term "substantially" refers to a degree of precision within an acceptable margin of error, where the acceptable margin of error is considered to reflect minute real-world variations resulting from material composition, material defects, and / or limitations / peculiarities during the manufacturing process. Such variations can therefore be described as achieving the stated characteristics to a large extent, but not necessarily to the full extent.

[0017] Figure 1 is a perspective view of the optical transmission component 1 according to the first embodiment of this disclosure. Figure 2 is a side view of the optical transmission component 1 in Figure 1. Figure 3 is a bottom view of the cover 12 of the optical transmission component 1 in Figure 1. Figure 4 is a side view of the cover 12 in Figure 3. Figure 5 is a perspective view of the optical transmission component 1 in Figure 1 with the top cover 124 removed. Figure 6 is a top view of the optical transmission component 1 in Figure 5. Figure 7 is a cross-sectional view of the optical transmission component 1 in Figure 5.

[0018] According to one embodiment, the optical transmission assembly 1 may include a metal base 11, a cover 12, a laser secondary mounting base 13, a laser chip 14, a first collimating lens 15, and a passive optical device 16.

[0019] In one embodiment, the metal base 11 may be a metal plate, and the metal plate may be coupled to the housing of a circuit board assembly (PCBA) or an optical module. In another embodiment, the metal base 11 may be a gold-plated ceramic substrate, and gold plating may be provided in the area where the cover 12 contacts the metal base 11 to enable soldering between the two.

[0020] In one embodiment, the cover 12 may have an annular bottom surface 121. In one embodiment, the annular bottom surface 121 may be welded to the metal base 11 so that the cover 12 and the metal base 11 together form a hermetically sealed space HS. In one embodiment, the cover 12 may be welded to the mounting surface 111 of the metal base 11 to define a covered area 1111 and an exposed area 1112 of the mounting surface 111. In one embodiment, the annular bottom surface 121 may surround the covered area 1111, and the passive optical device 16 may be coupled to the exposed area 1112.

[0021] In one embodiment, the cover 12 may include a housing 122, a feedthrough 123, and a top cover 124. In one embodiment, the top cover 124 may be welded to the housing 122. In one embodiment, the housing 122 and the feedthrough 123 may be welded to the metal base 11, but this disclosure is not limited thereto. In other embodiments, the feedthrough is welded to the housing, and the housing is welded to the metal base. In one embodiment, the housing 122 and the feedthrough 123 may be welded to the metal base 11 using Ag72Cu28 solder, Ti active solder, or Cr active solder, but this disclosure is not limited thereto. In one embodiment, the feedthrough 123 may be a ceramic feedthrough. In other embodiments, the feedthrough may have a stepped shape.

[0022] In one embodiment, the housing 122 may include a housing body 1221 and a light-transmitting window 1222 embedded in the housing body 1221. In one embodiment, the housing 122 and the feedthrough member 123 may jointly form an annular bottom surface 121, but this disclosure is not limited thereto. In other embodiments, the annular bottom surface is formed solely by the housing.

[0023] In one embodiment, the laser secondary mounting base 13 may be coupled to the metal base 11 and located within the hermetically sealed space HS. In one embodiment, the laser secondary mounting base 13 may have a first bearing surface 131 and a second bearing surface 132 facing away from the metal base 11. In one embodiment, the first bearing surface 131 may be closer to the metal base 11 than the second bearing surface 132. In one embodiment, the laser secondary mounting base 13 may be formed of aluminum nitride or silicon carbide.

[0024] In one embodiment, the laser chip 14 may be coupled to the second carrier surface 132. In one embodiment, the laser chip 14 may be thermally coupled to the second carrier surface 132. In one embodiment, the feedthrough 123 may supply power to the laser chip 14 via a gold wire bridge to enable the laser chip 14 to emit light. In one embodiment, the output facet of the laser chip 14 may provide optical power suitable for use in a co-packaged optical system (CPO). In one embodiment, the output facet of the laser chip 14 may provide a continuous optical signal with a power greater than or equal to 25 dBm. In one embodiment, the output facet of the laser chip 14 may provide a continuous optical signal with a power greater than or equal to 26 dBm. For edge-emitting lasers (EELs), the output facet refers to the side surface of the laser chip 14.

[0025] In one embodiment, the first collimating lens 15 may be coupled to the first carrier surface 131. In another embodiment, the first collimating lens 15 may be thermally coupled to the first carrier surface 131. In yet another embodiment, the first collimating lens 15 may be eutectic bonded to the first carrier surface 131, but this disclosure is not limited thereto. In other embodiments, the first collimating lens may be coupled to the first carrier surface by optical coupling adhesive. When the first collimating lens 15 and the laser wafer 14 are respectively coupled to the first carrier surface 131 and the second carrier surface 132 of the laser submount 13, the laser submount 13 can serve as an integrated heat sink. Therefore, when the laser submount 13 thermally expands or contracts, the relative positional shift between the collimating lens and the laser wafer can be minimized, thereby providing high optical coupling efficiency in high-temperature environments. The aforementioned high-temperature environment may refer to the temperature of the hermetically sealed packaging space HS when the laser wafer 14 operates at maximum power, which is typically greater than or equal to 100°C. The aforementioned high-temperature environment can also refer to the welding temperature at which the cover 12 is welded to the metal base 11, which can typically be close to 1000°C.

[0026] In one embodiment, the passive optical device 16 can be coupled to the metal base 11 for stable mounting. In one embodiment, the passive optical device 16 can be located outside the hermetically sealed space HS. In one embodiment, the laser chip 14 can be optically coupled to the passive optical device 16 through the first collimating lens 15. In one embodiment, the first collimating lens 15 can be optically coupled to the passive optical device 16 through the light-transmitting window 1222. In one embodiment, the passive optical device 16 can be spatially separated from the side wall surface 1223 of the housing 122.

[0027] In one embodiment, the passive optical device 16 may include a sleeve 161, a second collimating lens 162, a ceramic ferrule 163, and a polarization-maintaining fiber 164, but this disclosure is not limited thereto. In other embodiments, the passive optical device may include other components. In one embodiment, the second collimating lens 162, the ceramic ferrule 163, and the polarization-maintaining fiber 164 may be located within the sleeve 161. In one embodiment, the second collimating lens 162 may be a C-lens. In one embodiment, the laser chip 14 may be optically coupled to the second collimating lens 162 and the polarization-maintaining fiber 164. In one embodiment, the passive optical device 16 may be adapted to receive a circular light spot. In one embodiment, the optical coupling efficiency of the optical transmission component 1 may reach greater than or equal to 90% and less than or equal to 95%. In one embodiment, the polarization state can be maintained by employing the polarization-maintaining fiber 164.

[0028] In one embodiment, the passive optical device 16 may further include an optical platform 165. In one embodiment, the optical platform 165 may be coupled to a metal base 11. In one embodiment, a sleeve 161, a second collimating lens 162, a ceramic ferrule 163, and a polarization-maintaining fiber 164 may be mounted on the optical platform 165.

[0029] In one embodiment, the optical platform 165 can be coupled to the metal base 11 via optical coupling adhesive. In this embodiment, the height of the optical platform 165 can be matched to the height of the laser chip 14 to precisely control the thickness of the adhesive at the bottom of the passive optical device 16, optimize the stress state during fixation, and avoid polarization state disturbances (polarization crosstalk deterioration) caused by uneven adhesive layer or stress.

[0030] In one embodiment, the optical transmission component 1 may further include an optical isolator 17. In one embodiment, the optical isolator 17 may be coupled to a metal base 11. In one embodiment, the laser chip 14 may be optically coupled to the passive optical device 16 sequentially through a first collimating lens 15, the optical isolator 17, and the light-transmitting window 1222.

[0031] In one embodiment, the optical transmission component 1 may further include a thermoelectric cooler 18. In one embodiment, one side of the thermoelectric cooler 18 is coupled to the laser submount 13 and the optical isolator 17, and the other side of the thermoelectric cooler 18 is coupled to the metal base 11.

[0032] Other embodiments will be listed below for illustration. It should be noted that the following embodiments use the component reference numerals and some content from the foregoing embodiments, where the same reference numerals represent the same or similar components, and descriptions of the same technical content are omitted. For explanations of the omitted parts, please refer to the foregoing embodiments; these will not be repeated in the following embodiments.

[0033] Figure 8 is a cross-sectional schematic diagram of an optical transmission component 1a according to a second embodiment of the present disclosure.

[0034] The difference between optical transmission component 1a and optical transmission component 1 is that the passive optical device 16a of optical transmission component 1a may include an optical platform 161a, a second collimating lens 162a, an optical fiber array 163a, and a polarization-maintaining fiber 164.

[0035] In one embodiment, the optical platform 161a may be coupled to the metal base 11. In one embodiment, the second collimating lens 162a may be an aspherical lens. In one embodiment, the laser chip 14 may be optically coupled to the second collimating lens 162a, the fiber array 163a, and the polarization-maintaining fiber 164. In one embodiment, the passive optical device 16a may be adapted to receive an elliptical light spot.

[0036] Figure 9 is a cross-sectional schematic diagram of the optical transmission component 1b according to the third embodiment of this disclosure.

[0037] In this embodiment, the housing 122b of the cover 12b may include a housing body 1221b and a light-transmitting window 1222 embedded in the housing body 1221b.

[0038] In one embodiment, the annular bottom surface 121b of the cover 12b is formed only from the bottom of the housing 122b.

[0039] In one embodiment, the feedthrough 123b of the optical transmission component 1b is welded to the housing 122b of the cover 12b, and the annular bottom surface 121b of the housing 122b is welded to the metal base 11.

[0040] Figure 10 is a cross-sectional schematic diagram of an optical transmission component 1c according to a fourth embodiment of the present disclosure.

[0041] In this embodiment, the housing 122c of the cover 12c may include a housing body 1221c and a light-transmitting window 1222 embedded in the housing body 1221c.

[0042] In one embodiment, the annular bottom surface 121c of the cover 12c is formed by the housing 122c.

[0043] In one embodiment, the feedthrough 123c of the optical transmission component 1c is welded to the housing 122c of the cover 12c, and the annular bottom surface 121c of the housing 122c is welded to the metal base 11.

[0044] Figure 11 is a perspective view of an externally pluggable laser optical module 2 according to a fifth embodiment of the present disclosure. Figure 12 is a schematic diagram of some components of the externally pluggable laser optical module 2 in Figure 11.

[0045] According to one embodiment, the external laser pluggable optical module 2 may include a housing 21, a circuit board assembly 22, and an optical transmission component disclosed herein (e.g., at least one of optical transmission component 1, optical transmission component 1a, optical transmission component 1b, and optical transmission component 1c). The following describes the case where the external laser pluggable optical module 2 includes multiple optical transmission components 1, but this disclosure is not limited thereto.

[0046] In one embodiment, the circuit board assembly 22 may be located within the housing 21. In one embodiment, the optical transmission assembly 1 may be located within the housing 21. In one embodiment, the metal base 11 may be located within the housing 21 and coupled to the circuit board assembly 22.

[0047] In one embodiment, the external laser pluggable optical module 2 may further include a heat sink 23. In one embodiment, the heat sink 23 may be thermally coupled to the outside of the housing 21.

[0048] In one embodiment, the optical power of the laser chip 14 is greater than the final optical power of the externally pluggable laser optical module 2. In another embodiment, the optical output interface of the externally pluggable laser optical module 2 provides a continuous optical signal with a power greater than or equal to 23 dBm. In an embodiment where the externally pluggable laser optical module 2 is applied to a co-packaged optical system, the optical output interface may refer to the light-emitting end face of a blind-mating connector or the light-emitting end face of the polarization-maintaining fiber 164.

[0049] Figure 13 is a schematic diagram of an optoelectronic device 3 according to an embodiment of the present disclosure. The optoelectronic device 3 is used to optically couple an optical module 4 to an optical engine 331. The optoelectronic device 3 uses a polarization-maintaining fiber 34 to optically couple the optical module 4 to the optical engine 331. The optoelectronic device 3 may include a housing 31. The optoelectronic device 3 may also include a panel 32 located on one side of the housing 31. The optoelectronic device 3 may also include an assembly 33. The assembly 33 includes a substrate housed within the housing 31, and the substrate may include one or more circuit boards. The assembly 33 also includes an optical engine 331 mounted on the substrate.

[0050] Assembly 33 may also include an application-specific integrated circuit (ASIC) 332 mounted on the substrate. Optical engine 331 may be coupled to ASIC 332 via electrical transmission 35. Optical engine 331 and other optical engines described herein may be configured to perform electro-optical conversion of high-speed signals. Electrical transmission 35 and other similar electrical transmissions enable the transmission of electrical signals between ASIC 332 and optical engine 331.

[0051] Optical module 4 is pluggably mounted on panel 32. One end of polarization-maintaining fiber 34 is optically coupled to optical module 4, and the other end of polarization-maintaining fiber 34 is optically coupled to optical engine 331. Optical module 4 may include the optical transmission components described in any embodiment of this disclosure. Optical module 4 and other similar optical modules may meet the requirements of external laser small form factor pluggable (ELSFP).

[0052] Furthermore, connector 36 can be mounted on panel 32. Connector 36 can be a fiber-to-fiber connector. One end of non-polarization-maintaining fiber 37 is optically coupled to connector 36, and the other end of non-polarization-maintaining fiber 37 is optically coupled to optical engine 331.

[0053] In summary, the optical transmission assembly and external laser pluggable optical module according to the embodiments disclosed herein, since the laser chip and the first collimating lens are coupled to the same laser submount, can ensure that the laser chip and the first collimating lens expand or contract synchronously when the temperature changes, thereby reducing thermal drift of their relative positions, suppressing optical path offset, and achieving high optical coupling efficiency.

[0054] Furthermore, the laser secondary mounting bracket disclosed herein provides a low thermal resistance path for the laser chip and the first collimating lens, thereby improving the heat dissipation efficiency of the optical transmission component and helping the laser chip to operate stably at high power. Moreover, even after the sealing process (the process of soldering the top cover to the housing, where the temperature can reach over 1000°C) and under various operating temperatures, the optical transmission component can still maintain the stability of the optical path alignment.

[0055] 1, 1a, 1b, 1c: Optical transmission components 11: Metal base 111: Mounting surface 1111: Covered Area 1112: Exposed Area 12, 12b, 12c: Covering parts 121, 121b, 121c: Annular base 122, 122b, 122c: Shell 1221, 1221b, 1221c: Shell body 1222: Light-transmitting window 1223: Side wall surface 123, 123b, 123c: Feedthrough components 124: Top Cover 13: Laser secondary mounting base 131: First bearing surface 132: Second bearing surface 14: Laser Chip 15: First collimating lens 16,16a: Passive optical devices 161: Sleeve 162, 162a: Second collimating lens 163: Ceramic ferrule 163a: Fiber optic array 164: Polarization-maintaining fiber 165, 161a: Optical Platform 17: Optical isolator 18: Semiconductor Cooler HS: Hermetically sealed space 2: External laser pluggable optical module 21: Outer shell 22: Circuit board assembly 23: Radiator 3: Optoelectronic equipment 31: Chassis 32: Panel 33: Assembly 331: Light Engine 332: Application-Specific Integrated Circuits 34: Polarization-maintaining fiber 35: Electrical transmission 36: Connector 37: Non-polarization-maintaining fiber 4: Optical Module

Claims

1. An optical transmission component, comprising: a metal base; a cover having an annular bottom surface welded to the metal base such that the cover and the metal base together form a hermetically sealed space; a laser secondary mounting base coupled to the metal base and located within the hermetically sealed space, the laser secondary mounting base having a first bearing surface and a second bearing surface facing away from the metal base, the first bearing surface being closer to the metal base than the second bearing surface; a laser chip coupled to the second bearing surface; a first collimating lens coupled to the first bearing surface; and a passive optical device coupled to the metal base and located outside the hermetically sealed space, the laser chip being optically coupled to the passive optical device through the first collimating lens.

2. The optical transmission assembly as claimed in claim 1, wherein the cover includes a housing, a feedthrough and a top cover, the housing and the feedthrough are welded to the metal base, the housing includes a light-transmitting window, the first collimating lens is optically coupled to the passive optical device through the light-transmitting window, and the top cover is welded to the housing.

3. The optical transmission assembly as claimed in claim 2, wherein the housing and the feedthrough element together form the annular bottom surface.

4. The optical transmission assembly as described in claim 2, wherein the annular bottom surface is formed solely by the housing.

5. The optical transmission assembly as claimed in claim 2, wherein the passive optical device is spatially separated from the sidewall of the housing.

6. The optical transmission assembly as claimed in claim 1, wherein the cover is welded to a mounting surface of the metal base to define a covered area and an exposed area of ​​the mounting surface, the annular bottom surface surrounds the covered area, and the passive optical device is coupled to the exposed area.

7. The optical transmission assembly as claimed in claim 1, wherein the passive optical device comprises a sleeve, a second collimating lens, a ceramic ferrule, and a polarization-maintaining fiber, the second collimating lens, the ceramic ferrule, and the polarization-maintaining fiber being located within the sleeve, and the laser chip being optically coupled to the second collimating lens and the polarization-maintaining fiber.

8. The optical transmission assembly as claimed in claim 7, wherein the passive optical device further includes an optical platform coupled to the metal base, and the sleeve, the second collimating lens, the ceramic ferrule and the polarization-maintaining fiber are carried on the optical platform.

9. The optical transmission assembly as claimed in claim 1, wherein the passive optical device comprises an optical platform, a second collimating lens, an optical fiber array, and a polarization-maintaining fiber, the optical platform being coupled to the metal substrate, and the laser chip being optically coupled to the second collimating lens, the optical fiber array, and the polarization-maintaining fiber.

10. The optical transmission assembly as claimed in claim 1, wherein the first collimating lens is eutecticly bonded to the first bearing surface.

11. The optical transmission component as claimed in claim 1, wherein the output end face of the laser chip provides a continuous optical signal with a power greater than or equal to 25 dBm.

12. An externally mounted pluggable laser optical module, comprising: a housing; a circuit board assembly located within the housing; a metal base located within the housing and coupled to the circuit board assembly; a cover having an annular bottom surface welded to the metal base such that the cover and the metal base together form a hermetically sealed space; a laser secondary mounting base coupled to the metal base and located within the hermetically sealed space, the laser secondary mounting base having a first bearing surface and a second bearing surface facing away from the metal base, the first bearing surface being closer to the metal base than the second bearing surface; a laser chip coupled to the second bearing surface; a first collimating lens coupled to the first bearing surface; and a passive optical device coupled to the metal base and located outside the hermetically sealed space, the laser chip being optically coupled to the passive optical device through the first collimating lens.

13. An external laser pluggable optical module as described in claim 12, wherein the cover includes a housing, a feedthrough and a top cover, the housing and the feedthrough are welded to the metal base, the housing includes a light-transmitting window, the first collimating lens is optically coupled to the passive optical device through the light-transmitting window, and the top cover is welded to the housing.

14. An externally pluggable laser optical module as described in claim 13, wherein the housing and the feedthrough form the annular bottom surface together.

15. An externally pluggable laser optical module as described in claim 13, wherein the annular bottom surface is formed solely by the housing.

16. An external laser pluggable optical module as described in claim 13, wherein the passive optical device is spatially separated from the sidewall of the housing.

17. An external laser pluggable optical module as described in claim 12, wherein the cover is soldered to a mounting surface of the metal base to define a covered area and an exposed area of ​​the mounting surface, the annular bottom surface surrounds the covered area, and the passive optical device is coupled to the exposed area.

18. An external laser pluggable optical module as described in claim 12, wherein the passive optical device includes a sleeve, a second collimating lens, a ceramic ferrule, and a polarization-maintaining fiber, wherein the second collimating lens, the ceramic ferrule, and the polarization-maintaining fiber are located within the sleeve, and the laser chip is optically coupled to the second collimating lens and the polarization-maintaining fiber.

19. The external laser pluggable optical module as described in claim 18, wherein the passive optical device further includes an optical platform coupled to the metal base, and the sleeve, the second collimating lens, the ceramic ferrule and the polarization-maintaining fiber are carried on the optical platform.

20. An external laser pluggable optical module as described in claim 12, wherein the passive optical device includes an optical platform, a second collimating lens, an optical fiber array, and a polarization-maintaining fiber, the optical platform being coupled to the metal substrate, and the laser chip being optically coupled to the second collimating lens, the optical fiber array, and the polarization-maintaining fiber.

21. An external laser pluggable optical module as described in claim 12, wherein the first collimating lens is eutecticly bonded to the first bearing surface.

22. An external laser-pluggable optical module as described in claim 12, wherein the optical output interface of the external laser-pluggable optical module provides a continuous optical signal with a power greater than or equal to 23 dBm.

Images