Liquid cooling optical module, photoelectric conversion unit and manufacturing method thereof

Abstract

The invention provides a liquid cooling optical module, a photoelectric conversion unit and a manufacturing method thereof. The photoelectric conversion unit comprises a circuit board with a photoelectric conversion element; the light guide block comprises a light guide block body arranged on the circuit board, an optical signal interface arranged on the light guide block body and an element cavity which is arranged on the light guide block body and is used for accommodating a photoelectric conversion element, and the light guide block body is used for establishing an optical path between the optical signal interface and the element cavity; the first sealing adhesive is arranged between the bottom surface of the light guide block body and the circuit board and is arranged outside the element cavity in a surrounding manner; and the second sealing adhesive is arranged between the bottom surface of the light guide block body and the circuit board and is arranged outside the first sealing adhesive in a surrounding manner. The photoelectric conversion unit has a more excellent sealing effect.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of optical communication technology. More specifically, the present invention relates to a photoelectric conversion unit, a method for manufacturing the photoelectric conversion unit, and a liquid-cooled optical module including the photoelectric conversion unit. Background Art

[0002] Liquid-cooled optical modules are mainly used to achieve the conversion between electrical signals and optical signals, and are one of the core components of optical communication systems. They have significant advantages such as fast heat dissipation, low energy consumption and high data rate, and have been widely used in data centers, cloud computing, and high-speed communications.

[0003] The liquid-cooled optical module is mainly composed of a housing, a photoelectric conversion unit, and a fiber jumper connected to the photoelectric conversion unit. The photoelectric conversion unit includes a circuit board equipped with a photoelectric conversion element (such as a chip), and a light guide block bonded to the circuit board and covering the photoelectric conversion element and coupled to the fiber jumper. The function of the light guide block is to build an optical path between the fiber jumper and the circuit board, so that the photoelectric conversion element on the circuit board can receive the optical signal from the fiber jumper through the light guide block, or transmit the optical signal to the fiber jumper.

[0004] At present, liquid-cooled optical modules use a series of sealing measures to prevent the coolant from entering the light guide block and damaging (corroding or accelerating aging) the photoelectric conversion elements. These measures include potting glue covering the fiber jumper and the light guide block, and a sealing adhesive layer arranged between the light guide block and the circuit board. Although these two layers of sealing protection can provide a certain degree of protection, they may still fail due to aging or corrosion in an environment where they are immersed in coolant for a long time, causing the coolant to penetrate into the light guide block and damage the photoelectric conversion elements, ultimately affecting the normal operation of the photoelectric conversion elements and even the entire liquid-cooled optical module. Therefore, how to further improve the sealing protection level of the liquid-cooled optical module, especially the photoelectric conversion unit, especially the sealing level between the light guide block and the circuit board is a problem that urgently needs to be solved in this field. Summary of the invention

[0005] In order to solve one or more technical problems mentioned above, the present invention provides a photoelectric conversion unit, a method for manufacturing the photoelectric conversion unit, and a liquid-cooled optical module including the photoelectric conversion unit, wherein the photoelectric conversion unit has a better sealing effect, which can reduce the risk of cooling liquid penetrating into the light guide block and damaging the photoelectric conversion element, thereby ensuring that the liquid-cooled optical module can operate stably for a long time in the cooling liquid and transmit data efficiently and with high quality.

[0006] According to a first aspect of the present invention, there is provided a photoelectric conversion unit, comprising: a circuit board having a photoelectric conversion element; a light guide block, comprising a light guide block body arranged on the circuit board, an optical signal interface arranged on the light guide block body, and an element cavity arranged on the light guide block body and used to accommodate the photoelectric conversion element, wherein the light guide block body is used to establish an optical path between the optical signal interface and the element cavity; a first sealing adhesive, which is arranged between the bottom surface of the light guide block body and the circuit board and is arranged in a circumferential manner outside the element cavity; and a second sealing adhesive, which is arranged between the bottom surface of the light guide block body and the circuit board and is arranged in a circumferential manner outside the first sealing adhesive.

[0007] According to a second aspect of the present invention, a method for manufacturing a photoelectric conversion unit is provided, the steps of which include: preparing a circuit board of the photoelectric conversion unit, wherein the circuit board includes a circuit board having an electrical signal terminal, and a photoelectric conversion element arranged on the circuit board and electrically connected to the electrical signal terminal; preparing a light guide block of the photoelectric conversion unit, wherein the light guide block includes a light guide block body, an optical signal interface arranged on the light guide block body, and an element cavity arranged on the light guide block body, wherein the light guide block body is used to establish an optical path between the optical signal interface and the photoelectric conversion unit; applying a first adhesive and a second adhesive on the light guide block, and then attaching the light guide block to the circuit board and accommodating the photoelectric conversion element through the element cavity, wherein the first adhesive forms a first sealing adhesive of the photoelectric conversion unit after curing, the first sealing adhesive is formed between the light guide block and the circuit board and surrounds the outside of the photoelectric conversion element, and the second adhesive forms a second sealing adhesive of the photoelectric conversion unit after curing, the second sealing adhesive is formed between the light guide block and the circuit board and surrounds the outside of the first sealing adhesive.

[0008] According to a third aspect of the present invention, a liquid-cooled optical module is provided, comprising: a housing including an optical port; a photoelectric conversion unit, which is selected as the photoelectric conversion unit as described in the first aspect of the present invention and is arranged in the housing; and a fiber optic jumper, which is arranged in the housing and has one end arranged in the optical port and the other end inserted into and fixed in the optical signal interface of the light guide block of the photoelectric conversion unit.

[0009] According to a fourth aspect of the present invention, a liquid-cooled optical module is provided, which includes: a housing; a photoelectric conversion unit, which is selected as the photoelectric conversion unit as described in the first aspect of the present invention and is arranged in the housing; and an optical fiber jumper, which is arranged in the housing and has one end extending out of the housing and the other end inserted into and fixed in the optical signal interface of the light guide block of the photoelectric conversion unit.

[0010] In the photoelectric conversion unit, the manufacturing method of the photoelectric conversion unit and the liquid-cooled optical module including the photoelectric conversion unit provided above, the applicant has innovatively added two layers of sealing protection between the light guide block and the circuit board, namely, a first sealing adhesive arranged in a circumferential manner outside the element cavity of the light guide block and a second sealing adhesive arranged in a circumferential manner outside the first sealing adhesive. Compared with the prior art method in which there is only one layer of sealing protection, this at least two layers of sealing protection can significantly enhance the isolation effect between the photoelectric conversion unit and the coolant, further reduce the risk of the coolant penetrating into the light guide block and damaging the photoelectric conversion element, and ensure that the liquid-cooled optical module can operate stably for a long time in the coolant and transmit data efficiently and with high quality.

[0011] In addition, the photoelectric conversion unit is also provided with an annular glue groove and a glue injection hole connected thereto on the light guide block body, ensuring that the added third sealing adhesive can be formed in the annular glue groove and the glue injection hole by filling, and the light guide block and the circuit board are bonded and sealed again between the first sealing adhesive and the second sealing adhesive. The third sealing adhesive can not only further reduce the risk of coolant penetrating into the light guide block and damaging the photoelectric conversion element, ensuring that the liquid-cooled optical module can operate stably for a longer period of time in the coolant and transmit data efficiently and with high quality, but also can increase the bonding area and bonding strength of the light guide block on the circuit board. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] By reading the following detailed description with reference to the accompanying drawings, the above and other objects, features and advantages of the exemplary embodiments of the present invention will become readily understood. In the accompanying drawings, several embodiments of the present invention are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0013] Figure 1 A perspective view of a photoelectric conversion unit according to an embodiment of the present invention is shown;

[0014] Figure 2 A cross-sectional view of a photoelectric conversion unit according to an embodiment of the present invention is shown;

[0015] Figure 3 Shows Figure 1 A three-dimensional diagram of a light guide block of the photoelectric conversion unit shown;

[0016] Figure 4 Shows Figure 1 A cross-sectional view of a light guide block of the photoelectric conversion unit shown;

[0017] Figure 5 Shows Figure 1 A bottom view of the light guide block of the photoelectric conversion unit is shown.

[0018] Explanation of the reference numerals: 1. Circuit board; 11. Photoelectric conversion element; 2. Light guide block; 20. Potting glue; 21. Light guide block body; 21a. Block body; 21b. Base; 211. Top surface; 212. Bottom surface; 2121. First ring frame adhesive area; 2122. Second ring frame adhesive area; 22. Optical signal interface; 23. Component cavity; 24. Ring-shaped glue groove; 24a. First cavity top; 24b. Second cavity top; 25. Glue injection hole; 26. First converging lens; 27. Second converging lens; 28. Cavity; 281. Reflecting surface; 29. ​​Cover; 3. First sealing glue; 4. Second sealing glue; 5. Third sealing glue; 100. Photoelectric conversion unit; 300. Fiber jumper. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present disclosure.

[0020] This embodiment provides a photoelectric conversion unit 100, which is mainly used in a liquid-cooled optical module to realize the core function of the liquid-cooled optical module, that is, to realize the conversion between electrical signals and optical signals. Figure 1 and Figure 2 1 and 2 show a photoelectric conversion unit 100 according to an embodiment of the present invention. Figure 1 and Figure 2 As shown, the photoelectric conversion unit 100 includes a circuit board 1, a light guide block 2 provided on the circuit board 1, and a first sealing adhesive 3 and a second sealing adhesive 4 for bonding the light guide block 2 to the circuit board 1. The circuit board 1 includes a photoelectric conversion element 11 provided on its board body, and the photoelectric conversion element 11 is mainly composed of an optical chip and an electric chip electrically connected thereto. When the photoelectric conversion unit 100 is used to receive an optical signal and convert it into an electric signal, the optical chip receives the optical signal (from the optical fiber jumper 300) through the light guide block 2 and converts it into an electric signal, and the electric chip is used to perform processing such as signal amplification and filtering on the electric signal and output it externally. Conversely, when the photoelectric conversion unit 100 is used to receive an electric signal and convert it into an optical signal, the electric chip is used to drive the optical chip so that the optical chip can convert the received electric signal into an optical signal and output it externally through the light guide block 2. It can be understood that the optical fiber jumper 300 is a cable with an optical fiber connector at one end, which may have an outer sheath or may not have an outer sheath, and is selected according to its usage scenario.

[0021] Next, combine Figures 2 to 5 The light guide block 2 mentioned above is exemplified. Figures 2 to 4As shown, the light guide block 2 mentioned above mainly includes a light guide block body 21 provided on the circuit board 1, an optical signal interface 22 provided on the light guide block body 21, and an element cavity 23 provided on the bottom surface 212 of the light guide block body 21 (i.e., the surface joined to the circuit board 1) and used to accommodate the photoelectric conversion element 11, wherein the light guide block body 21 is used to establish an optical path between the optical signal interface 22 and the element cavity 23. Among them, the optical signal interface 22 is used to connect the optical fiber jumper 300 of the liquid-cooled optical module, so that the optical fiber jumper 300 can perform optical communication with the photoelectric conversion unit 100 through the light guide block 2. Among them, the optical fiber jumper 300 can be one optical fiber or multiple optical fibers. When multiple optical fibers are included, the optical signals output by the multiple optical fibers can be propagated in multiple optical paths of the light guide block 2 and enter the photoelectric conversion unit 100, and the photoelectric conversion unit 100 performs signal conversion.

[0022] In order to improve the sealing protection level of the photoelectric conversion unit 100, as Figure 4 and Figure 5 As shown, the bottom surface 212 of the light guide block body 21 includes a first ring frame adhesive area 2121 arranged in a surrounding manner outside the element cavity 23, and a second ring frame adhesive area 2122 arranged in a surrounding manner outside the first ring frame adhesive area 2121. The second ring frame adhesive area 2122 is preferably arranged at the edge of the bottom surface 212 of the light guide block body 21. The photoelectric conversion unit 100 also includes a first sealing adhesive 3 and a second sealing adhesive 4 arranged between the bottom surface 212 of the light guide block body 21 and the circuit board 1, see Figure 2 and Figure 5 . Among them, the first sealing adhesive 3 is provided in the first ring frame adhesive area 2121 of the bottom surface 212 of the light guide block body 21, and is arranged in a circumferential manner outside the component cavity 23, while the second sealing adhesive 4 is provided in the second ring frame adhesive area 2122 of the bottom surface 212 of the light guide block body 21, and is arranged in a circumferential manner outside the first sealing adhesive 3. However, since the prior art only arranges a layer of sealing adhesive between the bottom surface 212 of the light guide block body 21 and the circuit board 1, while the present embodiment arranges at least two layers of sealing adhesive, the isolation effect between the photoelectric conversion unit 100 and the coolant can be significantly enhanced, and the risk of the coolant penetrating into the light guide block 2 and damaging (corroding or accelerating aging) the photoelectric conversion element 11 can be further reduced, ensuring that the liquid-cooled optical module can operate stably for a long time in the coolant and transmit data efficiently and with high quality.

[0023] It should be particularly emphasized that even if the width of a layer of sealing adhesive in the prior art is relatively wide, or even the sum of the aforementioned two layers of sealing adhesive in this embodiment, it is not as good as the sealing effect of this embodiment. The reason is that the double-layer sealing adhesive design in this embodiment not only provides physical redundant protection, but also enhances the service life of the sealing protection. First of all, the two layers of sealing adhesive require two molding processes. Even if one of the two has quality defects due to poor molding, the other can be remedied immediately. Secondly, the time when the two layers of sealing adhesive contact the coolant is not the same. The outer second sealing adhesive 4 contacts the coolant before the inner first sealing adhesive 3, ensuring that the first sealing adhesive 3 is less likely to be damaged by the coolant than the second sealing adhesive 4. This can greatly reduce the risk of coolant infiltration into the light guide block 2, ensuring that the aforementioned double-layer sealing protection has a more obvious advantage in long-term protection effect.

[0024] In order to further improve the sealing protection level of the photoelectric conversion unit 100, the photoelectric conversion unit 100 of this embodiment has an additional sealing protection. Figure 2 and Figure 3 As shown, the light guide block 2 may further include an annular glue groove 24 provided on the bottom surface 212 of the light guide block body 21, and a glue injection hole 25 provided on the light guide block body 21 and connected to the annular glue groove 24. At the same time, the photoelectric conversion unit 100 may further include a third sealing adhesive 5 (see FIG. 1 ) filled in the annular glue groove 24 and the glue injection hole 25 and used to bond the light guide block 2 to the circuit board 1. Figure 2 ). Since the annular adhesive groove 24 is located between the first ring frame adhesive area 2121 and the second ring frame adhesive area 2122, and the first sealing adhesive 3 and the second sealing adhesive 4 are sequentially arranged in the first ring frame adhesive area 2121 and the second ring frame adhesive area 2122, the third sealing adhesive 5 is located between the first sealing adhesive 3 and the second sealing adhesive 4. The third sealing adhesive 5 can not only further reduce the risk of the coolant penetrating into the light guide block 2 and damaging the photoelectric conversion element 11, ensuring that the liquid-cooled optical module can operate stably for a longer period of time in the coolant and transmit data efficiently and with high quality, but also increase the bonding area and bonding strength of the light guide block 2 on the circuit board 1.

[0025] As an example, Figure 4As described, the central axis of the optical signal interface 22 is parallel to the bottom surface 212 of the light guide block body 21, and the light guide block 2 may also include a first converging lens 26 disposed on the light guide block body 21 and located in the optical signal interface 22, a second converging lens 27 disposed on the light guide block body 21 and located in the element cavity 23, and a cavity 28 disposed on the top surface 211 (a surface opposite to the bottom surface 212 and away from the circuit board 1) of the light guide block body 21 and having a reflective surface 281, wherein the optical axes of the first converging lens 26 and the second converging lens 27 intersect vertically on the reflective surface 281, and are both in the optical path of the light guide block 2. Among them, the arrangement of the first converging lens 26 and the second converging lens 27 makes the optical signal less lost during the transmission process and the light beam more concentrated, thereby improving the stability and reliability of the transmission process. In addition, the reflective surface 281 can change the trend of the optical path and promote the volume of the light guide block 2 to be more compact, thereby ensuring that the layout of the photoelectric conversion unit 100 and the liquid-cooled optical module is more compact and reduces their space occupancy.

[0026] In order to effectively control the volume of the light guide block 2, the optical signal interface 22 and the annular adhesive groove 24 are constructed so that their orthographic projections on the bottom surface 212 of the light guide block body 21 intersect, which is conducive to reducing the volume of the light guide block 2. In addition, the annular adhesive groove 24 includes a first cavity top 24a and a second cavity top 24b that is closer to the top surface 211 of the light guide block body 21 than the first cavity top 24a. Among them, the first cavity top 24a is located between the optical signal interface 22 and the bottom surface 212 of the light guide block body 21, and the second cavity top 24b is higher than the first cavity top 24a but lower than the top surface 211 of the light guide block body 21, and the glue injection hole 25 is connected to the annular adhesive groove 24 at the position where the second cavity top 24b is located. The cavity top of the annular adhesive groove 24 adopts a stepped surface design, and the glue injection hole 25 is set at a higher cavity top position. This layout allows the adhesive to be smoothly and evenly added to the annular adhesive groove 24, especially filling the lower area of ​​the cavity top. In this way, the third sealing adhesive 5 formed by curing the adhesive can effectively play the role of bonding and sealing.

[0027] In order to further improve the bonding and sealing effects of the third sealing adhesive 5, the distance from the first cavity top 24a of the annular adhesive groove 24 to the bottom surface 212 of the light guide block body 21 is preferably 0.4-0.5 mm. Through a large number of experiments, it is verified that when the distance from the first cavity top 24a of the annular adhesive groove 24 to the bottom surface 212 of the light guide block body 21 is 0.4-0.5 mm, the strength of the light guide block body 21 at the first cavity top 24a of the annular adhesive groove 24 is sufficient, and the adhesive can fill the annular adhesive groove 24 more fully and evenly.

[0028] In this embodiment, the first sealing adhesive 3, the second sealing adhesive 4 and the third sealing adhesive 5 are all cured by light-curing or heat-curing adhesives. Light-curing adhesives cure quickly under light conditions, while heat-curing adhesives cure by heating. These two curing methods ensure that the adhesive can quickly form a strong adhesive force during the curing process, thereby improving the reliability and efficiency of the connection and sealing. As a preferred embodiment, the first sealing adhesive 3 and the third sealing adhesive 5 can be made of heat-curing adhesives. The light guide block 2 is made of a transparent material that allows curing light such as ultraviolet rays to pass through, but the brightness and uniformity of the light-curing adhesive are significantly reduced, affecting the molding quality and effect of the first sealing adhesive 3 and the third sealing adhesive 5. Therefore, in order to improve the molding quality and effect, the first sealing adhesive 3 and the third sealing adhesive 5 are more recommended to be made of heat-curing adhesives, so that the molding quality and effect of the first sealing adhesive 3 and the third sealing adhesive 5 can be better.

[0029] As an example, the frame edge widths of the first ring frame adhesive area 2121 and the second ring frame adhesive area 2122 are both 0.5 to 1 mm. When the frame edge widths of the first ring frame adhesive area 2121 and the second ring frame adhesive area 2122 are precisely controlled within the range of 0.5 to 1 mm, it can not only provide sufficient bonding area for bonding with the first sealing adhesive 3 and the second sealing adhesive 4, and ensure that the first sealing adhesive 3 and the second sealing adhesive 4 can fully exert the connection function and sealing function, but also ensure that the wall structure of the light guide block body 21 used to form the first ring frame adhesive area 2121 and the second ring frame adhesive area 2122 has good mechanical strength, and ensure that the wall structure is not prone to breakage and other adverse conditions during assembly and use.

[0030] Similarly, the groove width of the annular adhesive groove 24 is 1 to 2 mm. The groove width of the annular adhesive groove 24 is precisely controlled at 1 to 2 mm, ensuring that the adhesive can flow and distribute smoothly and evenly in the injection hole 25 and the annular adhesive groove 24, and form a uniform and continuous third sealing adhesive 5 between the light guide block 2 and the circuit board 1, thereby ensuring that the third sealing adhesive 5 can achieve more outstanding effects in bonding and sealing.

[0031] Preferably, the injection hole 25 is a through hole with an aperture of 0.5 to 1 mm. Such an aperture design is large enough to adapt to the size of a common glue gun nozzle to ensure that the adhesive can be smoothly injected into the annular glue groove 24, and small enough to reduce the impact on the structural strength of the light guide block body 21. In addition, the aperture of the injection hole 25 does not exceed the groove width (1 to 2 mm) of the annular glue groove 24 and can be smoothly connected thereto, ensuring that the adhesive can completely fill the space in the groove during the injection and curing process to form a uniform sealing adhesive.

[0032] Preferably, the shortest distance between the side wall of the element cavity 23 and the photoelectric conversion element 11 is 0.5 to 1 mm. This distance ensures that the side wall of the element cavity 23 of the light guide block 2 is not easy to contact and damage the sensitive photoelectric conversion element 11. In particular, the aforementioned adverse situation is avoided from occurring during the process of pasting the light guide block 2 to the circuit board 1. It should be noted that the side wall of the element cavity 23 is the surface connected to the surface where the second converging lens 27 is located. It can be understood that in practice, in order to reduce the difficulty of processing the circuit board 1, the photoelectric conversion element 11 is generally close to the vertical surface of the element cavity 23 close to the optical signal interface 22.

[0033] In this embodiment, the light guide block 2 is preferably an integrated molding structure to simplify the manufacturing process and improve the overall quality and performance. At the same time, the light guide block body 21 includes a base 21b and a block body 21a fixed on the base 21b, wherein the optical signal interface 22, the first converging lens 26, the second converging lens 27 and the cavity 28 are all formed in the block body 21a, and the annular adhesive groove 24 and the element cavity 23 are formed in the base 21b and the block body 21a, and the cross-sectional area of ​​the base 21b is greater than the cross-sectional area of ​​the block body 21a. Due to the requirements of its high-precision structure, the block body 21a usually requires the use of high-precision manufacturing molds and manufacturing processes to ensure the accuracy of its optical and mechanical properties, while the base 21b mainly plays a connecting and accommodating role, and its processing accuracy requirements are relatively low. In other words, it is only necessary to open a groove for forming the base 21b in the existing manufacturing mold, and the existing manufacturing mold and process can be used to manufacture the aforementioned light guide block 2, which is beneficial to reduce its manufacturing cost and processing difficulty.

[0034] As an example, the cross-sections of the base 21b and the block body 21a of the light guide block body 21 in the direction perpendicular to the ground are both circular, rectangular or polygonal, but preferably rectangular for ease of manufacture. In addition, some material reduction notches may be provided in the block body 21a, for example, two material reduction notches symmetrically arranged about the optical signal interface 22 may be provided on the rectangular block body 21a, so as to reduce the material and weight of the light guide block 2 as much as possible.

[0035] In this embodiment, the light guide block 2 may further include a cover 29 fixedly disposed on the top surface 211 of the light guide block body 21 and sealing the cavity 28, see Figure 2. The reflective surface 281 is generally a full reverse surface formed by the different refractive indexes of the material of the light guide block 2 and the air. If there are impurities in the cavity 28, it will affect the effect of the emitting surface 281. The cover 29 can prevent dust, moisture and other harmful substances from entering the cavity 28 of the light guide block 2, ensuring that the performance of the reflective surface 281 is always at the best level. In order to achieve a better sealing of the photoelectric conversion unit 100, the photoelectric conversion unit 100 may also include a potting material 20 arranged on the circuit board 1 and covering the cover 29, the light guide block 2 and the optical fiber jumper 300 near the light guide block 2. The potting material 20 takes precedence over the first sealing adhesive 3, the second sealing adhesive 4 and the third sealing adhesive 5 in terms of sealing protection, and provides reinforcement and sealing enhancement for the cover 29. In addition, the potting material 20 can also effectively prevent pollutants such as dust and bacteria from damaging the photoelectric conversion unit 100.

[0036] Next, the manufacturing method of the above-mentioned photoelectric conversion unit 100 is introduced, and the steps include preparing the circuit board 1 and the light guide block 2 of the photoelectric conversion unit 100, and then first applying the first adhesive and the second adhesive on the bottom surface 212 of the light guide block body 21 of the light guide block 2, and then attaching the light guide block 2 to the circuit board 1 and accommodating the photoelectric conversion element 11 through the element cavity 23. The first adhesive is mainly applied to the first ring frame adhesive area 2121 of the bottom surface 212 of the light guide block body 21 of the light guide block 2, and can be formed into the first sealing adhesive 3 of the photoelectric conversion unit 100 after curing; and the second adhesive is mainly applied to the second ring frame adhesive area 2122 of the bottom surface 212 of the light guide block body 21 of the light guide block 2, and can be formed into the second sealing adhesive 4 of the photoelectric conversion unit 100 after curing. In the photoelectric conversion unit 100 obtained by this manufacturing method, the first sealing adhesive 3 and the second sealing adhesive 4 can further reduce the risk of the coolant penetrating into the light guide block 2 and damaging the photoelectric conversion element 11, ensuring that the liquid-cooled optical module can operate stably for a long time in the coolant and transmit data efficiently and with high quality.

[0037] In this embodiment, the manufacturing method may further include: injecting a third adhesive into the annular adhesive groove 24 through the adhesive injection hole 25 until the annular adhesive groove 24 and the adhesive injection hole 25 are completely filled, wherein the third adhesive forms a third sealing adhesive 5 of the photoelectric conversion unit 100 after curing. The third adhesive is injected through the adhesive injection hole 25 to form the third sealing adhesive 5, and it is ensured that the third sealing adhesive 5 can further reduce the risk of the coolant penetrating into the light guide block 2 and damaging the photoelectric conversion element 11.

[0038] As an example, the first adhesive, the second adhesive and the third adhesive are all light-curing or heat-curing adhesives, and the sources can be the same or different. Light-curing adhesives cure quickly under light conditions, and heat-curing adhesives cure by heating. These two curing methods ensure that the adhesives can quickly form strong adhesion during the curing process, thereby improving the reliability and efficiency of connection and sealing.

[0039] In one embodiment, the first adhesive and the second adhesive are photocurable and heat-curable adhesives, and they have the same source. The multilayer structure of the light guide block 2 blocks ultraviolet light, resulting in the first sealing adhesive 3 and / or the second sealing adhesive 4, especially the first sealing adhesive 3 located below the thicker light guide block. The use of photocurable adhesives has problems such as low curing efficiency and incomplete curing; using adhesives from the same source can not only save the trouble of replacing the glue gun when applying the glue. . It can be understood that when curing the first sealing adhesive 3 and the second sealing adhesive 4 of the photoelectric conversion unit 100, they are first cured by ultraviolet light and then baked at high temperature until the first sealing adhesive 3 and the second sealing adhesive 4 are cured. It should be noted that the first sealing adhesive 3 and the second sealing adhesive 4 are cured by ultraviolet light so that the light guide block 2 is bonded to the circuit board 1, ensuring that the light guide block 2 does not shift during high-temperature baking.

[0040] In one embodiment, the third adhesive is a low-viscosity heat-curing glue with good wettability. The third adhesive is injected into the annular adhesive groove 24 through the glue injection hole 25. The low-viscosity glue with good wettability has good fluidity and can fully fill the annular adhesive groove 24. The third sealing adhesive 5 is relatively thick, and the use of a light-curing adhesive is prone to problems such as insufficient internal curing. The use of heat-curing glue has a better molding effect. It is understandable that the third adhesive that completely fills the annular adhesive groove 24 and the glue injection hole 25 is cured by high-temperature baking to form the third sealing adhesive 5.

[0041] In this embodiment, the steps of the manufacturing method may also include: inserting and fixing the optical fiber jumper 300 into the optical signal interface 22 of the light guide block 2 of the optoelectronic conversion unit 100, so that the optical fiber jumper 300 can perform optical communication with the optoelectronic conversion element 11 of the optoelectronic conversion unit 100 through the light guide block 2; covering the cover 29; adding potting glue to the circuit board 1 of the optoelectronic conversion unit 100 and covering the cover 29, the light guide block 2 and the end of the optical fiber jumper 300 near the light guide block 2, until the potting glue forms the potting glue material 20 of the optoelectronic conversion unit 100 after curing. Therefore, the potting glue material 20 formed by curing the potting glue can provide additional sealing protection and structural reinforcement for the entire optoelectronic conversion unit 100. It can be understood that in the present invention, the execution order of covering the cover and inserting the optical fiber jumper can be interchanged, that is, the optical fiber jumper can be inserted first, and then the cover can be covered, or the cover can be covered first, and then the optical fiber jumper is inserted. Both sequences can achieve the same technical effect.

[0042] Next, the application of the above-mentioned optoelectronic conversion unit 100 in two types of liquid-cooled optical modules is introduced. In one application scenario, the liquid-cooled optical module includes a housing having an optical port and an electrical port, a photoelectric conversion unit arranged in the housing and electrically connected to the electrical port, and an optical fiber jumper 300 arranged in the housing and one end of which is located at the optical port of the optical module and the other end is inserted into and fixed in the optical signal interface 22 of the light guide block 2 of the optoelectronic conversion unit. Among them, the optoelectronic conversion unit is also selected as the above-mentioned optoelectronic conversion unit 100. Due to its excellent sealing and protective performance, it can operate permanently and efficiently even when immersed in cooling liquid. Therefore, the liquid-cooled optical module can improve its own reliability and durability by means of the optoelectronic conversion unit 100, and ensure that the liquid-cooled optical module becomes an ideal choice in communication systems with high heat dissipation requirements. It should be noted that the optical port of the optical module is used for optical communication with the outside, and the optical fiber jumper 300 is located at one end of the optical port of the optical module for receiving optical signals or outputting optical signals of the optical module.

[0043] In another application scenario, the liquid-cooled optical module includes a housing with an electrical port, a photoelectric conversion unit arranged in the housing and electrically connected to the electrical port, and a fiber jumper 300 arranged in the housing and extending out of the housing at one end (connecting other optical fibers or another liquid-cooled optical module) and inserted and fixed at the other end in the optical signal interface 22 of the light guide block 2 of the photoelectric conversion unit. Among them, the photoelectric conversion unit is also selected as the photoelectric conversion unit 100 mentioned above. One end of the fiber jumper of this optical module extends out of the housing and can be directly coupled with another jumper through an adapter. Plastic parts such as tail sleeves are provided on the side of the optical module away from the electrical interface. The housing can be interference-fitted with the tail sleeve to further optimize the sealing performance of the liquid-cooled optical module. Due to its excellent sealing and protective performance, it can operate persistently and efficiently even when immersed in coolant. Therefore, the liquid-cooled optical module can improve its own reliability and durability through the photoelectric conversion unit 100, and ensure that the liquid-cooled optical module becomes an ideal choice for communication systems with high heat dissipation requirements.

[0044] In the above description of the present application, unless otherwise clearly specified and limited, the terms "fixed", "installed", "connected" or "connected" and the like should be understood in a broad sense. For example, with regard to the term "connection", it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements. Therefore, unless otherwise clearly defined in the present application, those skilled in the art can understand the specific meanings of the above terms in the present invention according to the specific circumstances.

[0045] According to the above description of the present application, those skilled in the art may also understand that the terms used below, such as "top", "bottom", "inside", "outside" and other terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings of the present application, which are only for the purpose of facilitating the explanation of the scheme of the present invention and simplifying the description, rather than explicitly or implicitly indicating that the devices or elements involved must have the specific orientation, be constructed and operated in a specific orientation. Therefore, the above-mentioned orientation or positional relationship terms cannot be understood or interpreted as limitations on the scheme of the present invention.

[0046] In addition, the terms "first" or "second" used in this application to refer to numbers or ordinals are only used for descriptive purposes and cannot be understood as explicitly or implicitly indicating relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this application, the meaning of "plurality" is at least two, such as two, three or more, etc., unless otherwise clearly and specifically defined.

[0047] Although multiple embodiments of the present invention have been shown and described herein, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Those skilled in the art may conceive of many changes, modifications, and alternatives without departing from the thought and spirit of the present invention. It should be understood that in the process of practicing the present invention, various alternatives to the embodiments of the present invention described herein may be adopted. The appended claims are intended to define the scope of protection of the present invention, and therefore cover equivalents or alternatives within the scope of these claims.

Claims

1. A photoelectric conversion unit, characterized in that: It includes: A circuit board having a photoelectric conversion element; A light guide block, comprising a light guide block body disposed on the circuit board, an optical signal interface disposed on the light guide block body, and an element cavity disposed on the light guide block body and used to accommodate the photoelectric conversion element, wherein the light guide block body is used to establish an optical path between the optical signal interface and the element cavity; A first sealing adhesive is provided between the bottom surface of the light guide block body and the circuit board and is arranged in a surrounding manner outside the component cavity; and The second sealing adhesive is disposed between the bottom surface of the light guide block body and the circuit board and is arranged outside the first sealing adhesive in a surrounding manner.

2. The photoelectric conversion unit according to claim 1, characterized in that: The light guide block also includes an annular glue groove arranged on the bottom surface of the light guide block body, and a glue injection hole arranged on the light guide block body and connected to the annular glue groove. The photoelectric conversion unit also includes a third sealing adhesive filled in the annular glue groove and the glue injection hole and used to bond the light guide block to the circuit board. The third sealing adhesive is located between the first sealing adhesive and the second sealing adhesive.

3. The photoelectric conversion unit according to claim 2, characterized in that: The optical signal interface and the annular adhesive groove intersect with each other in their orthographic projections on the bottom surface of the light guide block body.

4. The photoelectric conversion unit according to claim 3, characterized in that: The annular glue groove includes a first cavity top and a second cavity top that is closer to the top surface of the light guide block body than the first cavity top, the first cavity top is located between the optical signal interface and the bottom surface of the light guide block body, the second cavity top is higher than the first cavity top but lower than the top surface of the light guide block body, and the glue injection hole is connected to the annular glue groove at the position of the second cavity top.

5. The photoelectric conversion unit according to any one of claims 2 to 4, characterized in that: The bottom surface of the light guide block body includes a first ring frame adhesive area and a second ring frame adhesive area separated by the annular adhesive groove and connected to the first sealing adhesive and the second sealing adhesive in sequence. The frame edge widths of the first ring frame adhesive area and the second ring frame adhesive area are both 0.5-1mm.

6. The photoelectric conversion unit according to any one of claims 2 to 4, characterized in that: The central axis of the optical signal interface is parallel to the bottom surface of the light guide block body, and the light guide block also includes a first converging lens arranged on the light guide block body and located in the optical signal interface, a second converging lens arranged on the light guide block body and located in the element cavity, and a cavity arranged on the top surface of the light guide block body and having a reflecting surface, wherein the optical axes of the first converging lens and the second converging lens intersect vertically on the reflecting surface and are both in the optical path; the photoelectric conversion unit also includes a cover fixedly arranged on the top surface of the light guide block body and sealing the cavity; the photoelectric conversion unit is applied in an optical module, and the optical signal interface is used to connect the optical fiber jumper of the optical module so that the optical fiber jumper can perform optical communication with the photoelectric conversion unit through the light guide block, and the photoelectric conversion unit also includes a potting adhesive material arranged on the circuit board and covering the cover, the light guide block and the portion of the optical fiber jumper close to the light guide block.

7. A method for manufacturing a photoelectric conversion unit, characterized in that: The steps include: preparing a wiring board of the photoelectric conversion unit, wherein the wiring board has a photoelectric conversion element; preparing a light guide block of the photoelectric conversion unit, the light guide block comprising a light guide block body disposed on the circuit board, an optical signal interface disposed on the light guide block body, and an element cavity disposed on the light guide block body, wherein the light guide block body is used to establish an optical path between the optical signal interface and the element cavity; and Apply a first adhesive and a second adhesive to the bottom surface of the light guide block body of the light guide block, then attach the light guide block to the circuit board and accommodate the photoelectric conversion element through the element cavity, wherein the first adhesive forms a first sealing adhesive of the photoelectric conversion unit after curing, the first sealing adhesive is formed between the light guide block and the circuit board and surrounds the photoelectric conversion element, and the second adhesive forms a second sealing adhesive of the photoelectric conversion unit after curing, the second sealing adhesive is formed between the light guide block and the circuit board and surrounds the first sealing adhesive.

8. The manufacturing method according to claim 7, characterized in that: The light guide block further comprises an annular glue groove provided on the light guide block body and surrounding the outside of the element cavity, and a glue injection hole provided on the light guide block body and communicating with the annular glue groove; The manufacturing method also includes the steps of: injecting a third adhesive into the annular adhesive groove through the glue injection hole until the annular adhesive groove and the glue injection hole are completely filled, wherein the third adhesive forms a third sealing adhesive of the photoelectric conversion unit after curing, and the third sealing adhesive is used to bond the light guide block to the circuit board and is located between the first sealing adhesive and the second sealing adhesive.

9. The manufacturing method according to claim 7, characterized in that: The photoelectric conversion unit further comprises a cover fixedly arranged on the top surface of the light guide block body and sealing the cavity of the light guide block body; The photoelectric conversion unit is applied in an optical module, and the optical signal interface is used to connect an optical fiber jumper of the optical module; The steps of the manufacturing method also include: inserting and fixing the optical fiber jumper into the optical signal interface of the light guide block of the photoelectric conversion unit so that the optical fiber jumper can perform optical communication with the photoelectric conversion element of the photoelectric conversion unit through the light guide block; adding potting glue to the circuit board of the photoelectric conversion unit and covering the cover, the light guide block and the part of the optical fiber jumper close to the light guide block until the potting glue forms a potting glue material of the photoelectric conversion unit after curing.

10. A liquid-cooled optical module, characterized in that: It includes: A housing having an optical port; a photoelectric conversion unit, which is the photoelectric conversion unit according to any one of claims 1 to 6 and is arranged in the housing; as well as An optical fiber jumper is arranged in the housing and is configured as follows: one end of the optical fiber jumper is arranged in the optical port and the other end is inserted into and fixed in the optical signal interface of the light guide block of the optoelectronic conversion unit; or one end of the optical fiber jumper extends out of the housing and the other end is inserted into and fixed in the optical signal interface of the light guide block of the optoelectronic conversion unit.

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