CN117826342A

CN117826342A - Optical module

Info

Publication number: CN117826342A
Application number: CN202211204022.0A
Authority: CN
Inventors: 邵乾; 刘维伟; 张强; 张晓廓
Original assignee: Hisense Broadband Multimedia Technology Co Ltd
Current assignee: Hisense Broadband Multimedia Technology Co Ltd
Priority date: 2022-09-29
Filing date: 2022-09-29
Publication date: 2024-04-05

Abstract

The application discloses an optical module, including optical transceiver assembly. The optical transceiver assembly comprises a transceiver housing and a third circuit board. The receiving and transmitting shell is provided with an optical window at the first end, an inserting port for inserting the third circuit board at the second end, and an optical assembly inside. The third circuit board is provided with a hollowed-out area. The optical component comprises a laser chip, a first lens, a lithium niobate chip, a second lens, a second optical filter, a third lens, a receiving turning prism and a light receiving chip. The laser chip, the first lens, the second optical filter, the receiving turning prism, the third lens and the light receiving chip are all positioned at the first end of the receiving-transmitting shell, and the lithium niobate chip is positioned at the second end of the receiving-transmitting shell. The lithium niobate chip is arranged corresponding to the hollowed-out area. In the application, the laser chip provides high-power light, and the light loss of the lithium niobate chip is smaller than that of the silicon light chip, so that the modulated light signal modulated by the lithium niobate chip meets the requirement of the light power of light emitted by 50 GPON.

Description

Optical module

Technical Field

The application relates to the technical field of optical fiber communication, in particular to an optical module.

Background

The international standard ITU-T g.9804.3 for 50G GPON has been promulgated at month 9 in 2021. To maintain the current PON 29dB/32dB link budget, the 50G PON standard places higher demands on the optical power of the light emitted by the OLT optical module. The current conventional EML of 53GBaud cannot meet the optical power requirement of light emitted from the 50G PON.

In order to meet the requirement of 50G PON standard on the optical power of the light emitted by the OLT optical module, a lot of international factories develop EML+SOA chip schemes for 50G PON. However, the international factories currently developing the eml+soa chip scheme for 50G PON all encounter technical difficulties that are difficult to break through, and no eml+soa optical device for 50G PON OLT is currently proposed. Therefore, no optical module can meet the optical power requirement of the light emitted from the 50G PON.

Disclosure of Invention

The application provides an optical module which meets the requirement of the optical power of light emitted by a 50G PON.

An optical module, comprising:

the optical transceiver component comprises a transceiver shell and a third circuit board;

a receiving and transmitting shell, wherein the first end is provided with an optical window for emitting or injecting optical signals, the second end is provided with an inserting port for inserting a third circuit board, and an optical assembly is arranged in the receiving and transmitting shell;

the third circuit board is provided with a hollowed-out area;

the optical component comprises a laser chip, a first lens, a lithium niobate chip, a second lens, a second optical filter, a third lens, a receiving turning prism and a light receiving chip;

the laser chip, the first lens, the second optical filter, the receiving turning prism, the third lens and the light receiving chip are all positioned at the first end of the receiving-transmitting shell, and the lithium niobate chip is positioned at the second end of the receiving-transmitting shell;

A first lens located between the laser chip and the lithium niobate chip;

the lithium niobate chip is arranged corresponding to the hollowed-out area and comprises a substrate and a lithium niobate film, and the optical loss is less than 10dB;

the lithium niobate thin film is paved on the substrate, and the thickness is smaller than 100 mu m;

the second lens is positioned between the lithium niobate chip and the second optical filter;

the second optical filter is positioned between the laser chip and the third lens;

and the receiving turning prism is positioned above the light receiving chip.

The beneficial effects are that: the application provides an optical module, which comprises an optical transceiver component. The optical transceiver assembly comprises a transceiver housing and a third circuit board. The receiving and transmitting shell is provided with a light window for emitting or entering light signals at the first end, an inserting port for inserting a third circuit board at the second end, and an optical assembly inside the inserting port. The third circuit board is provided with a hollowed-out area. The first optical signal in the receiving and transmitting shell is emitted through the optical window, and the second optical signal in the optical fiber adapter is emitted into the receiving and transmitting shell through the optical window. The circuit board is inserted into the transceiver housing through the insertion opening. In order to ensure the tightness between the circuit board and the receiving and transmitting shell, a copper sheet is laid in the area of the circuit board corresponding to the insertion opening, the receiving and transmitting shell is a metal receiving and transmitting shell, and the circuit board is welded with the insertion opening of the receiving and transmitting shell, so that the tightness between the circuit board and the receiving and transmitting shell is ensured. The optical component comprises a laser chip, a first lens, a lithium niobate chip, a second lens, a second optical filter, a third lens, a receiving turning prism and a light receiving chip. The laser chip, the first lens, the second optical filter, the third lens, the receiving turning prism and the light receiving chip are all positioned at the first end of the receiving-transmitting shell, and the lithium niobate chip is positioned at the second end of the receiving-transmitting shell. The laser chip is a high-power DFB laser chip. The high-power DFB laser chip is used for emitting high-power light. And the first lens is positioned between the laser chip and the lithium niobate chip and is used for coupling high-power light to the lithium niobate chip. The lithium niobate chip is arranged corresponding to the hollowed-out area and comprises a substrate and a lithium niobate film, the optical loss is less than 10dB, and the lithium niobate chip is used for modulating high-power light to obtain a modulated optical signal. The lithium niobate thin film is paved on the substrate, and the thickness is smaller than 100 mu m. Because the lithium niobate chip is smaller and has higher integration precision, the lithium niobate chip has the advantages of low power consumption, low optical loss and the like compared with a silicon optical chip. The optical loss of the silicon optical chip is smaller than 11.2dB, and the optical loss of the lithium niobate chip is smaller than 10dB. Since the optical loss of the silicon optical chip is less than 11.2dB, in order for the optical module including the DFB laser chip+silicon optical chip combination to meet the requirement of the optical power of light emitted from the 50G PON, the optical power of light emitted from the DFB laser chip is required to be > 158mW. Since the optical loss of the lithium niobate chip is less than 10dB, in order for an optical module including the DFB laser chip+lithium niobate chip combination to meet the requirement of the optical power of light emitted from the 50G PON, the optical power of light emitted from the DFB laser chip is required to be > 80mW. The light power of the light emitted by the conventional DFB laser chip is less than 50mW, and the light power of the light emitted by the high-power DFB laser chip is less than 120mW. In the prior art, the light power of light emitted by the DFB laser chip is difficult to meet more than 120mW in a full-temperature state. Therefore, in order for the optical module to meet the optical power requirement of the light emitted by the 50G PON, the optical module can only use a combination of DFB laser chips and lithium niobate chips. And the second lens is positioned between the lithium niobate chip and the second optical filter and is used for collimating the modulated optical signals to obtain collimated optical signals. And the second optical filter is positioned between the laser chip and the third lens and is used for transmitting the collimated optical signals to the optical fiber adapter. And the third lens is positioned between the second optical filter and the receiving turning prism and is used for coupling the second optical signal reflected by the second optical filter to the receiving turning prism. And the receiving turning prism is positioned above the light receiving chip and is used for changing the second optical signal so as to reflect the second optical signal to the light receiving chip. In the application, the laser chip provides high-power light, the light loss of the lithium niobate chip is smaller than that of the silicon light chip, and the modulated light signal modulated by the lithium niobate chip meets the requirement of the light power of light emitted by the 50G PON.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments or the description of the prior art will be briefly introduced below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a diagram of the connection relationship of an optical communication system;

fig. 2 is a block diagram of an optical network terminal;

FIG. 3 is a diagram of an optical module architecture according to some embodiments;

FIG. 4 is an exploded block diagram of an optical module according to some embodiments;

FIG. 5 is a diagram of an optical module configuration with an upper housing removed according to some embodiments;

FIG. 6 is a block diagram of an optical transceiver assembly and a circuit board according to some embodiments;

FIG. 7 is an exploded view of an optical transceiver assembly and a circuit board according to some embodiments;

FIG. 8 is a first block diagram of an optical transceiver assembly according to some embodiments;

FIG. 9 is a second block diagram of an optical transceiver assembly according to some embodiments;

FIG. 10 is a first cross-sectional view of an optical transceiver assembly according to some embodiments;

FIG. 11 is a second cross-sectional view of an optical transceiver assembly according to some embodiments;

FIG. 12 is a third cross-sectional view of an optical transceiver assembly according to some embodiments;

FIG. 13 is an exploded view of an optical transceiver assembly according to some embodiments;

FIG. 14 is a block diagram of an optical transceiver module with an upper cover removed according to some embodiments;

FIG. 15 is a block diagram of an optical assembly and a third circuit board according to some embodiments;

FIG. 16 is a block diagram of an optical assembly according to some embodiments;

FIG. 17 is a block diagram of a third circuit board according to some embodiments;

FIG. 18 is a block diagram of a fiber optic adapter, focus ring, fourth lens, and lens holder according to some embodiments;

FIG. 19 is an exploded view of a fiber optic adapter, an adjustment ring, a fourth lens, and a lens holder according to some embodiments;

FIG. 20 is a first block diagram of a transceiver stem according to some embodiments;

FIG. 21 is a second block diagram of a transceiver stem according to some embodiments;

FIG. 22 is a third block diagram of a transceiver stem according to some embodiments;

FIG. 23 is an exploded view of a transceiver stem according to some embodiments;

FIG. 24 is a first cross-sectional view of a transceiver stem according to some embodiments;

FIG. 25 is a second cross-sectional view of a transceiver stem according to some embodiments;

FIG. 26 is a first optical path diagram of an optical module according to some embodiments;

fig. 27 is a second optical path diagram of an optical module according to some embodiments.

Detailed Description

In an optical communication system, an optical signal is used to carry information to be transmitted, and the optical signal carrying the information is transmitted to an information processing device such as a computer through an information transmission device such as an optical fiber or an optical waveguide, so as to complete the transmission of the information. Since light has a passive transmission characteristic when transmitted through an optical fiber or an optical waveguide, information transmission with low cost and low optical loss can be realized. Further, since a signal transmitted by an information transmission device such as an optical fiber or an optical waveguide is an optical signal and a signal that can be recognized and processed by an information processing device such as a computer is an electrical signal, it is necessary to perform mutual conversion between the electrical signal and the optical signal in order to establish an information connection between the information transmission device such as an optical fiber or an optical waveguide and the information processing device such as a computer.

The optical module realizes the function of interconversion between the optical signal and the electric signal in the technical field of optical communication. The optical module comprises an optical port and an electric port, the optical module realizes optical communication with information transmission equipment such as optical fibers or optical waveguides through the optical port, realizes electric connection with an optical network terminal (for example, optical cat) through the electric port, and the electric connection is mainly used for power supply, I2C signal transmission, data information transmission, grounding and the like; the optical network terminal transmits the electric signal to information processing equipment such as a computer through a network cable or wireless fidelity (Wi-Fi).

Fig. 1 is a connection diagram of an optical communication system. As shown in fig. 1, the optical communication system includes a remote server 1000, a local information processing device 2000, an optical network terminal 100, an optical module 200, an optical fiber 101, and a network cable 103.

One end of the optical fiber 101 is connected to the remote server 1000, and the other end is connected to the optical network terminal 100 through the optical module 200. The optical fiber itself can support long-range signal transmission, such as several kilometers (6 kilometers to 8 kilometers), on the basis of which, if a repeater is used, it is theoretically possible to achieve unlimited distance transmission. Thus, in a typical optical communication system, the distance between the remote server 1000 and the optical network terminal 100 may typically reach several kilometers, tens of kilometers, or hundreds of kilometers.

One end of the network cable 103 is connected to the local information processing device 2000, and the other end is connected to the optical network terminal 100. The local information processing apparatus 2000 may be any one or several of the following: routers, switches, computers, cell phones, tablet computers, televisions, etc.

The physical distance between the remote server 1000 and the optical network terminal 100 is greater than the physical distance between the local information processing apparatus 2000 and the optical network terminal 100. The connection between the local information processing apparatus 2000 and the remote server 1000 is completed by an optical fiber 101 and a network cable 103; and the connection between the optical fiber 101 and the network cable 103 is made by the optical module 200 and the optical network terminal 100.

The optical module 200 includes an optical port configured to access the optical fiber 101 such that the optical module 200 establishes a bi-directional optical signal connection with the optical fiber 101; the electrical port is configured to be accessed into the optical network terminal 100 such that the optical module 200 establishes a bi-directional electrical signal connection with the optical network terminal 100. The optical module 200 performs mutual conversion between optical signals and electrical signals, so that an information connection is established between the optical fiber 101 and the optical network terminal 100. Illustratively, the optical signal from the optical fiber 101 is converted into an electrical signal by the optical module 200 and then input to the optical network terminal 100, and the electrical signal from the optical network terminal 100 is converted into an optical signal by the optical module 200 and input to the optical fiber 101. Since the optical module 200 is a tool for implementing the mutual conversion between the optical signal and the electrical signal, it has no function of processing data, and the information is not changed during the above-mentioned photoelectric conversion process.

The optical network terminal 100 includes a substantially rectangular parallelepiped housing (housing), and an optical module interface 102 and a network cable interface 104 provided on the housing. The optical module interface 102 is configured to access the optical module 200, so that the optical network terminal 100 and the optical module 200 establish a bidirectional electrical signal connection; the network cable interface 104 is configured to access the network cable 103 such that the optical network terminal 100 establishes a bi-directional electrical signal connection with the network cable 103. A connection is established between the optical module 200 and the network cable 103 through the optical network terminal 100. Illustratively, the optical network terminal 100 transmits an electrical signal from the optical module 200 to the network cable 103, and transmits an electrical signal from the network cable 103 to the optical module 200, so that the optical network terminal 100, as a host computer of the optical module 200, can monitor the operation of the optical module 200. The upper computer of the optical module 200 may include an optical line terminal (Optical Line Terminal, OLT) or the like in addition to the optical network terminal 100.

The remote server 1000 establishes a bidirectional signal transmission channel with the local information processing device 2000 through the optical fiber 101, the optical module 200, the optical network terminal 100 and the network cable 103.

Fig. 2 is a block diagram of an optical network terminal, and fig. 2 shows only the configuration of the optical network terminal 100 related to the optical module 200 in order to clearly show the connection relationship between the optical module 200 and the optical network terminal 100. As shown in fig. 2, the optical network terminal 100 further includes a circuit board 105 disposed in the housing, a cage 106 disposed on a surface of the circuit board 105, a heat sink 107 disposed on the cage 106, and an electrical connector disposed inside the cage 106. The electrical connector is configured to access an electrical port of the optical module 200; the heat sink 107 has a convex portion such as a fin that increases the heat dissipation area.

The optical module 200 is inserted into the cage 106 of the optical network terminal 100, the optical module 200 is fixed by the cage 106, and heat generated by the optical module 200 is transferred to the cage 106 and then diffused through the heat sink 107. After the optical module 200 is inserted into the cage 106, the electrical port of the optical module 200 is connected with an electrical connector inside the cage 106, so that the optical module 200 and the optical network terminal 100 propose a bi-directional electrical signal connection. In addition, the optical port of the optical module 200 is connected to the optical fiber 101, so that the optical module 200 establishes a bi-directional optical signal connection with the optical fiber 101.

Fig. 3 is a block diagram of an optical module according to some embodiments. Fig. 4 is an exploded structural view of an optical module according to some embodiments. As shown in fig. 3 and 4, the optical module 200 includes a housing (shell), a circuit board 300 disposed in the housing, and an optical transceiver assembly 400.

The housing includes an upper housing 201 and a lower housing 202, the upper housing 201 being covered on the lower housing 202 to form the above-mentioned housing having two openings; the outer contour of the housing generally presents a square shape.

In some embodiments of the present disclosure, the lower housing 202 includes a bottom plate 2021 and two lower side plates 2022 disposed at both sides of the bottom plate 2021 and perpendicular to the bottom plate 2021; the upper housing 201 includes a cover 2011, and the cover 2011 is covered on two lower side plates 2022 of the lower housing 202 to form the housing.

In some embodiments, the lower housing 202 includes a bottom plate 2021 and two lower side plates 2022 disposed on both sides of the bottom plate 2021 and perpendicular to the bottom plate 2021; the upper housing 201 includes a cover 2011 and two upper side plates disposed on two sides of the cover 2011 and perpendicular to the cover 2011, and the two upper side plates are combined with two lower side plates 2022 to cover the upper housing 201 on the lower housing 202.

The direction in which the two openings 204 and 205 are connected may be the same as the longitudinal direction of the optical module 200 or may be different from the longitudinal direction of the optical module 200. For example, opening 204 is located at the end of light module 200 (right end of fig. 3) and opening 205 is also located at the end of light module 200 (left end of fig. 3). Alternatively, the opening 204 is located at the end of the light module 200, while the opening 205 is located at the side of the light module 200. The opening 204 is an electrical port, and the golden finger 301 of the circuit board 300 extends out from the electrical port 204 and is inserted into a host computer (for example, the optical network terminal 100); the opening 205 is an optical port configured to access the external optical fiber 101 such that the external optical fiber 101 connects to the optical transceiver assembly 400 inside the optical module 200.

The assembly mode of combining the upper shell 201 and the lower shell 202 is adopted, so that devices such as the circuit board 300 and the optical transceiver assembly 400 are conveniently installed in the shells, and packaging protection is formed on the devices by the upper shell 201 and the lower shell 202. In addition, when devices such as the circuit board 300 and the optical transceiver module 400 are assembled, the positioning component, the heat dissipation component and the electromagnetic shielding component of the devices are conveniently deployed, and the automatic production implementation is facilitated.

In some embodiments, the upper housing 201 and the lower housing 202 are generally made of metal materials, which is beneficial to electromagnetic shielding and heat dissipation.

In some embodiments, the optical module 200 further includes an unlocking member located outside of the housing thereof, the unlocking member being configured to enable or disable the fixed connection between the optical module 200 and the host computer.

Illustratively, the unlocking component is located on the outer walls of the two lower side plates 2022 of the lower housing 202, with a snap-in component that mates with an upper computer cage (e.g., cage 106 of the optical network terminal 100). When the optical module 200 is inserted into the cage of the upper computer, the optical module 200 is fixed in the cage of the upper computer by the clamping component of the unlocking component; when the unlocking component is pulled, the clamping component of the unlocking component moves along with the unlocking component, so that the connection relation between the clamping component and the upper computer is changed, the clamping relation between the optical module 200 and the upper computer is relieved, and the optical module 200 can be pulled out of the cage of the upper computer.

The circuit board 300 includes circuit traces, electronic components and chips, which are connected together by the circuit traces according to a circuit design to realize functions such as power supply, electrical signal transmission, and grounding. The electronic components include, for example, capacitors, resistors, transistors, metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET). The chips include, for example, a micro control unit (Microcontroller Unit, MCU), a laser driving chip, a limiting amplifier (limiting amplifier), a clock data recovery (Clock and Data Recovery, CDR) chip, a power management chip, a digital signal processing (Digital Signal Processing, DSP) chip.

The circuit board 300 is generally a hard circuit board, and the hard circuit board can also realize a bearing function due to the relatively hard material, for example, the hard circuit board can stably bear the electronic components and chips; when the optical transceiver component is positioned on the circuit board, the hard circuit board can also provide stable bearing; the hard circuit board can also be inserted into an electrical connector in the upper computer cage.

The circuit board 300 further includes a gold finger 301 formed on an end surface thereof, the gold finger 301 being composed of a plurality of pins independent of each other. The circuit board 300 is inserted into the cage 106 and is conductively connected to the electrical connectors within the cage 106 by the gold fingers 301. The golden finger 301 may be disposed on only one surface (such as the upper surface shown in fig. 4) of the circuit board 300, or may be disposed on both upper and lower surfaces of the circuit board 300, so as to adapt to the situation where the pin number is large. The golden finger 301 is configured to establish electrical connection with an upper computer to achieve power supply, grounding, I2C signal transfer, data signal transfer, and the like.

Of course, flexible circuit boards may also be used in some optical modules. The flexible circuit board is generally used in cooperation with the rigid circuit board to supplement the rigid circuit board. For example, a flexible circuit board may be used to connect the hard circuit board and the optical transceiver.

The optical transceiver module 400 is used for transmitting and receiving optical signals.

Fig. 5 is a diagram of an optical module configuration with the upper housing removed according to some embodiments. Fig. 6 is a block diagram of an optical transceiver assembly and a circuit board according to some embodiments. Fig. 7 is an exploded view of an optical transceiver assembly and a circuit board according to some embodiments. As can be seen in fig. 4-7, in some embodiments, the circuit board 300 includes a first circuit board 301 and a second circuit board 302, the first circuit board 301 being connected to the second circuit board 302. The first circuit board 301 is a hard circuit board, a first end is connected to a second end of the second circuit board 302, and a golden finger is disposed at the second end. The second circuit board 302 is a flexible circuit board, and has a first end connected to the optical transceiver module 400 and a second end connected to the first end of the first circuit board 301.

Fig. 8 is a first block diagram of an optical transceiver assembly according to some embodiments. Fig. 9 is a second block diagram of an optical transceiver assembly according to some embodiments. Fig. 10 is a first cross-sectional view of an optical transceiver assembly according to some embodiments. Fig. 11 is a second cross-sectional view of an optical transceiver assembly according to some embodiments. Fig. 12 is a third cross-sectional view of an optical transceiver assembly according to some embodiments. Fig. 13 is an exploded view of an optical transceiver assembly according to some embodiments. As can be seen in fig. 4-13, in some embodiments, the optical transceiver assembly 400 includes a transceiver housing 401, a fiber optic adapter 404, and a third circuit board 303. The first end of the transceiver housing 401 is provided with an optical window and the second end of the transceiver housing 401 is provided with an insertion port. The first end of the transceiver body 401 is connected with the lens fixing seat 405 through laser welding, the lens fixing seat 405 is welded at the optical window of the transceiver body 401, the lens fixing seat 405 is connected with the optical fiber adapter 404 through the focusing ring 406, and the third circuit board 303 is inserted into the transceiver body 401 through the insertion port.

Fig. 14 is a block diagram of an optical transceiver module with an upper cover removed according to some embodiments. Fig. 15 is a block diagram of an optical assembly and a third circuit board according to some embodiments. Fig. 16 is a block diagram of an optical assembly according to some embodiments. As can be seen in fig. 4-16, in some embodiments, transceiver housing 401 includes an upper cover 4011 and a transceiver stem 4012, wherein upper cover 4011 covers transceiver stem 4012, and upper cover 4011 encloses a hollow transceiver cavity with transceiver stem 4012. An optical component is arranged in the receiving and transmitting cavity. The optical component includes a laser chip 4021, a first lens 4022, an isolator 4023, a lithium niobate chip 4024, a second lens 4025, a second optical filter 4026, a third lens 4027, a receiving turning prism 40210, a light receiving chip 4028, and a transimpedance amplifying chip 40214. The laser chip 4021, the first lens 4022, the isolator 4023, the lithium niobate chip 4024, the second lens 4025, the second optical filter 4026, the third lens 4027, the receiving turning prism 40210, and the light receiving chip 4028 are all located on the transceiver seat 4012, and the transimpedance amplifier chip 40214 is located on the third circuit board 303. In particular, the method comprises the steps of,

the laser chip 4021 is configured to emit high-power light. Specifically, since the laser chip 4021 is a high-power DFB laser chip, the laser chip 4021 can provide high-power light. The wavelength of the high-power light emitted from the laser chip 4021 is λ1, and the high-power light emitted from the laser chip 4021 is divergent light.

Since the high-power light emitted from the laser chip 4021 is divergent light, in order to couple the divergent light emitted from the laser chip 4021 into the lithium niobate chip 4024, a first lens 4022 is provided between the laser chip 4021 and the lithium niobate chip 4024.

A first lens 4022, located between the laser chip 4021 and the lithium niobate chip 4024, for coupling the high-power light emitted from the laser chip 4021 into the lithium niobate chip 4024. Specifically, the first lens 4022 is a focusing lens that couples divergent light into the lithium niobate chip 4024.

The first lens 4022 may be a collimator lens and a focusing lens, in addition to a focusing lens. When the first lens 4022 is a collimator lens and a focusing lens, the first lens 4022 includes a first sub-lens 40221 and a second sub-lens 40222, the first sub-lens 40221 is a collimator lens, and the second sub-lens 40222 is a focusing lens. The first sub-lens 40221 collimates the divergent light to obtain collimated light. The second sub-lens 40222 in turn couples the collimated light focus into the lithium niobate chip 4024.

Since light coupled into the lithium niobate chip 4024 via the first lens 4022 may return along the way, the laser chip 4021 is damaged. In order to prevent light coupled into the lithium niobate chip 4024 via the first lens 4022 from returning along the way, an isolator 4023 is provided between the laser chip 4021 and the lithium niobate chip 4024.

An isolator 4023 for preventing light coupled into the lithium niobate chip 4024 via the first lens 4022 from returning along the way.

When the first lens 4022 is a focusing lens, the separator 4023 is located between the first lens 4022 and the lithium niobate chip 4024; when the first lens 4022 is a collimator lens and a focusing lens, the isolator 4023 is located between the first sub-lens 40221 and the second sub-lens 40222.

The international standard ITU-T g.9804.3 for 50G GPON has been promulgated at month 9 in 2021. To maintain the current PON 29dB/32dB link budget, the 50G PON standard requires that the optical power of the light emitted by the OLT optical module be greater than or equal to 8.5dBm. The current conventional EML of 53GBaud cannot meet the optical power requirement of light emitted from the 50G PON. In order to meet the requirement of 50G PON standard on the optical power of the light emitted by the OLT optical module, a lot of international factories develop EML+SOA chip schemes for 50G PON. However, the international factories currently developing the scheme of the EML+SOA chip for 50G PON all encounter technical problems that are difficult to break through, and no EML+SOA optical device for 50GPON OLT is yet proposed. Therefore, no optical module can meet the optical power requirement of the light emitted from the 50G PON.

To address this problem, in some embodiments, it is proposed that the optical module includes the use of a DFB laser chip+lithium niobate chip combination.

The lithium niobate chip 4024 includes a substrate, which is a glass substrate, and a lithium niobate thin film laid on the substrate. The thickness of the lithium niobate thin film is less than 100 μm. Because the lithium niobate chip is smaller and has higher integration precision, the lithium niobate chip has the advantages of low power consumption, low optical loss and the like compared with a silicon optical chip. The optical loss of the silicon optical chip is smaller than 11.2dB, and the optical loss of the lithium niobate chip is smaller than 10dB.

The thickness of the lithium niobate thin film is less than 100 μm, and in order to further reduce the size of the lithium niobate chip, in some embodiments, the thickness of the lithium niobate thin film is less than 20 μm. The size of the lithium niobate chip is further reduced, and the thickness of the lithium niobate thin film is smaller than 100 mu m.

Since the optical loss of the silicon optical chip is less than 11.2dB, in order for the optical module including the DFB laser chip+silicon optical chip combination to meet the requirement of the optical power of light emitted from the 50G PON, the optical power of light emitted from the DFB laser chip is required to be > 158mW. Since the optical loss of the lithium niobate chip is less than 10dB, in order for an optical module including the DFB laser chip+lithium niobate chip combination to meet the requirement of the optical power of light emitted from 50GPON, the optical power of light emitted from the DFB laser chip is required to be > 80mW.

The light power of the light emitted by the conventional DFB laser chip is less than 50mW, and the light power of the light emitted by the high-power DFB laser chip is less than 120mW. In the prior art, the light power of light emitted by the DFB laser chip is difficult to meet more than 120mW in a full-temperature state. Therefore, in order for the optical module to meet the optical power requirement of the light emitted by the 50G PON, the optical module can only use a combination of DFB laser chips and lithium niobate chips.

The lithium niobate chip 4024 is used for modulating high-power light. Specifically, an input interface and an output interface are disposed on one side of the lithium niobate chip 4024, an input optical waveguide, an MZ modulator and an output optical waveguide are disposed in the lithium niobate chip 4024, the input optical waveguide is connected with the input interface and the input end of the MZM modulator, and the output optical waveguide is connected with the output end of the MZM modulator and the output optical interface. The high-power light is incident into the input optical waveguide of the lithium niobate chip 4024 through the input interface, most of the high-power light received by the input optical waveguide is incident into the input end of the MZM modulator, the MZ modulator modulates the high-power light to obtain a modulated optical signal, the modulated optical signal is output to the output optical waveguide through the output end of the MZM modulator, and most of the modulated optical signal received by the output optical waveguide is output through the output interface. Wherein the modulated optical signal is a divergent optical signal.

The input interface and the output interface of the lithium niobate chip 4024 may also be provided on different sides of the lithium niobate chip 4024. However, if the input interface and the output interface of the lithium niobate chip 4024 are disposed on different sides of the lithium niobate chip 4024, the length of the lithium niobate chip 4024 may be increased, thereby increasing the length of the optical module in which the lithium niobate chip 4024 is packaged. Thus, to reduce the length dimension of the lithium niobate chip 4024, in some embodiments, one side of the lithium niobate chip 4024 may be provided with an input interface and an output interface.

The surface of the lithium niobate chip 4024 is provided with a first power monitor and a second power monitor, the first power monitor is located near an input optical waveguide of the lithium niobate chip 4024, the second power monitor is located near an output optical waveguide of the lithium niobate chip 4024, the first power monitor is used for monitoring a small part of light received by the input optical waveguide to realize monitoring optical power, and the second power monitor is used for monitoring a small part of optical signal received by the output optical waveguide to monitor whether the MZM modulator is at an optimal modulation point.

The lithium niobate chip can modulate high-power light (the light power emitted by the laser chip is more than 80 mW), and the light loss (the light loss is less than 10 dB) of the lithium niobate thin film modulator is less than that of the silicon light chip (the light loss is less than 11.2 dB), so that the modulated light signal can meet the light power of light emitted by 50G PON.

A second lens 4025, located between the lithium niobate chip 4024 and the second optical filter 4026, for collimating the optical signal output by the lithium niobate chip 4024. Specifically, since the optical signal output by the lithium niobate chip 4024 is a divergent optical signal, the second lens 4025 is a collimating lens, and the collimating lens collimates the divergent optical signal output by the lithium niobate chip 4024 to obtain a collimated optical signal.

The second filter 4026 is configured to transmit an optical signal with a specific wavelength, and reflect the second optical signal to the third lens 4027. Specifically, the second filter 4026 is configured to transmit an optical signal with a wavelength λ1, and reflect the second optical signal to the third lens 4027. The optical signal emitted through the optical window of the transceiver housing is a first optical signal, and the optical signal emitted through the optical window of the transceiver housing is a second optical signal.

The second optical filter 4026 may include two 45 ° triangular prisms, where the hypotenuses of the two 45 ° triangular prisms are bonded, and one hypotenuse is coated with a filter film; a glass sheet may also be included, wherein the end of the glass sheet facing the optical fiber is coated with a filter film. The second filter 4026 includes two 45 ° triangular prism designs for ease of manufacturing process operations. The second filter 4026 includes a glass sheet requiring a filter holder to be secured to the transceiver tube mount.

A third lens 4027, located between the second optical filter 4026 and the receiving turning prism 40210, for coupling the second optical signal reflected by the second optical filter 4026 to the receiving turning prism 40210. Specifically, the third lens 4027 is a focusing lens, and the focusing lens focuses and couples the second optical signal reflected by the second optical filter 4026 to the receiving turning prism 40210.

The receiving turning prism 40210 is configured to change the direction of the second optical signal, so that the light receiving chip 4028 receives the second optical signal. Specifically, since the photosensitive surface of the light receiving chip 4028 is disposed perpendicular to the third lens 4027, the light receiving chip 4028 cannot receive the second optical signal if the turning prism 40210 is not received. The reception turning prism 40210 is located above the light receiving chip 4028. The reception turning prism 40210 is configured to change the second optical signal coupled to via the third lens 4027 so that the light receiving chip 4028 receives the second optical signal.

In order for the light receiving chip 4028 to receive the second light signal as much as possible, in some embodiments, a reception turning prism 40210 is provided at the focal point of the light receiving chip 4028.

The angle of the receiving turning prism 40210 is 41 ° to 43 °. Specifically, the angle of the receiving turning prism 40210 cannot be set to 45 ° to avoid the second optical signal perpendicularly entering the light receiving chip, and reduce the reflection of the second optical signal. Therefore, the angle of the receiving turning prism 40210 is generally set to 41 ° to 43 °.

For example, the angle of the reception turning prism 40210 is 42 °, and the main optical axis incident to the light receiving chip 4028 is not perpendicular to the upper surface of the light receiving chip 4028 but forms an angle of 84 °. Thus, after a small portion of the second optical signal incident on the optical receiving chip 4028 is reflected by the optical receiving chip, the small portion of the second optical signal cannot be reflected back to the optical fiber adapter 404 along the original optical path.

The receiving turning prism 40210 may be connected to the third lens 4027 or disconnected from the third lens 4027. The receiving turning prism 40210 and the third lens 4027 are connected by an index matching adhesive.

When the receiving turning prism 40210 is not connected to the third lens 4027, the second optical signal sequentially passes through the incident surface of the third lens 4027, the exit surface of the third lens 4027, the incident surface of the receiving turning prism 40210, the reflection surface of the receiving turning prism 40210, and the exit surface of the receiving turning prism 40210 to be input into the light receiving chip.

Light is reflected at the interface of two different refractive indices. When the receiving turning prism 40210 is not connected to the third lens 4027, the second optical signal is easily reflected at the exit surface of the third lens 4027, and the incident surface of the receiving turning prism 40210 is also easily reflected. However, when the receiving turning prism 40210 is connected to the third lens 4027 through the index matching glue, the reflection of the exit surface of the third lens 4027 is not easy to occur due to the index matching glue, and the reflection of the incident surface of the receiving turning prism 40210 is not easy to occur, so that the optical loss of the second optical signal is reduced.

The receiving turning prism 40210 is connected to the third lens 4027, so that not only can the optical loss of the second optical signal be reduced, but also the occupied optical module space can be reduced.

The light receiving chip 4028 is located vertically below the receiving turning prism 40210 and is used for converting the received second light signal into a current signal. Specifically, the light receiving chip 4028 is provided with a photosurface, the photosurface receives the second optical signal, and the light receiving chip 4028 converts the second optical signal into a current signal.

Since the lithium niobate chip has a large size, in order to enable the lithium niobate chip to be packaged in an optical module of a conventional size, the lithium niobate chip 4024 is located at the second end of the transceiver socket, and the laser chip 4021, the first lens 4022, the isolator 4023, the second lens 4025, the second optical filter 4026, the third lens 4027, the receiving turning prism 40210, and the light receiving chip 4028 are located at the first end of the transceiver socket 4012. The first end of the transceiver socket 4012 is a first end of the transceiver housing 401, and the second end of the transceiver socket 4012 is a second end of the transceiver housing 401.

A transimpedance amplifier chip 40214 for converting the current signal into a voltage signal.

Fig. 17 is a block diagram of a third circuit board according to some embodiments. As can be seen in fig. 4-17, in some embodiments, the first end of the third circuit board 303 is provided with an open hollowed-out region 3033. The presence of the hollowed-out region 3033 makes the third circuit board 303U-shaped. The hollowed-out region 3033 is used to house a lithium niobate chip 4024. In order to facilitate placement of the lithium niobate chip 4024, the length dimension of the hollowed-out region 3033 is equal to or greater than the length dimension of the lithium niobate chip 4024, and the width dimension of the hollowed-out region 3033 is equal to or greater than the width dimension of the lithium niobate chip 4024.

The lithium niobate chip 4024 is provided with a first routing pin, and the third circuit board 303 is provided with a second routing pin, and the first routing pin and the second routing pin are correspondingly arranged. To minimize the routing distance between the first routing leg of the lithium niobate chip 4024 and the second routing leg of the third circuit board 303, in some embodiments, the width dimension of the hollowed-out region 3033 is equal to the width dimension of the lithium niobate chip 4024, and the length dimension of the hollowed-out region 3033 is equal to the length dimension of the lithium niobate chip 4024.

As can be seen in fig. 4-17, in some embodiments, the third circuit board 303 includes a first sub-circuit board 3031 and a second sub-circuit board 3032, and the first sub-circuit board 3031 and the second sub-circuit board 3032 are integrally formed. The second sub-circuit board 3032 is located at a first end of the third circuit board 303 and the first sub-circuit board 3031 is located at a second end of the third circuit board 303. The junction of the first sub-circuit board 3031 and the second sub-circuit board 3032 is provided with a second notch region 30322, the second sub-circuit board 3032 is provided with a first notch region 30321, and the first sub-circuit board 3031 is provided with a hollowed-out region 3033.

The first notch region 30321 is provided corresponding to the light receiving chip 4028, the connection region of the first side plate and the second side plate is provided corresponding to the second notch region 30322, and the second notch region 30322 is closer to the gold finger of the third circuit board 303 than the first notch region 30321.

The second sub-circuit board 3032 has a lower upper surface than the first sub-circuit board 3031. I.e. the second sub-circuit board 3032 is more recessed with respect to the first sub-circuit board 3031.

In order to shorten the wire bonding length between the transimpedance amplifier chip 40214 and the light receiving chip 4028 on the transceiver seat 4012 and thereby improve the high frequency performance of the signal wire, in some embodiments, the second sub-circuit board 3032 is obtained by cutting out a partial area of the first sub-circuit board 3031 by a plurality of layers, so that the second sub-circuit board 3032 is more concave relative to the first sub-circuit board 3031, and the transimpedance amplifier chip 40214 and some resistance and capacitance are disposed on the second sub-circuit board 3032.

The first end of the first sub-circuit board 3031 is close to the laser chip 4021, a golden finger is arranged at the tail end of the second end of the first sub-circuit board 3031, the third end of the first sub-circuit board 3031 is close to the light receiving chip 4028, the third end of the first sub-circuit board 3031 is connected with the second sub-circuit board 3032, and the third end of the first sub-circuit board 3031 is not connected with the first end of the first sub-circuit board 3031. Wherein, the first end of the first sub-circuit board 3031 and the third end of the first sub-circuit board 3031 are both located at the first end of the transceiver stem 4012, and the second end of the first sub-circuit board 3031 is located at the second end of the transceiver stem 4012.

Fig. 18 is a block diagram of a fiber optic adapter, focus ring, fourth lens, and lens holder according to some embodiments. Fig. 19 is an exploded view of a fiber optic adapter, an adjustment ring, a fourth lens, and a lens holder according to some embodiments. As can be seen in fig. 4-19, in some embodiments, a storage cavity is disposed in the lens holder 405, and a fourth lens 4029 is disposed in the storage cavity, and the fourth lens 4029 and the storage cavity are bonded by glue. The fourth lens 4029 is a focusing lens. The focusing lens is used to couple the first optical signal transmitted through the second optical filter 4026 to the optical fiber ferrule in the optical fiber adapter 404, and is also used to collimate the second optical signal incident by the optical fiber ferrule in the optical fiber adapter 404 into the second optical filter 4026.

As can be seen in fig. 4-19, in some embodiments, a focusing cavity is disposed in the focusing ring 406, and the focusing cavity is engaged with an end of the fiber optic adapter 404 facing the transceiver housing 401. During installation, the optical fiber adapter 404 and the lens fixing seat 405 are fixed in relative positions through optical coupling, and then the focusing ring 406 is used for fixing the relative positions of the optical fiber adapter 404 and the lens fixing seat 405.

Fig. 20 is a first block diagram of a transceiver socket according to some embodiments. Fig. 21 is a second block diagram of a transceiver socket according to some embodiments. Fig. 22 is a third block diagram of a transceiver socket according to some embodiments. Fig. 23 is an exploded view of a transceiver socket according to some embodiments. Fig. 24 is a first cross-sectional view of a transceiver stem according to some embodiments. Fig. 25 is a second cross-sectional view of a transceiver stem according to some embodiments. As can be seen in fig. 4-25, in some embodiments, a first end of the transceiver block 4012 is provided with a light aperture 401211 and a light window 401212, and a second end of the transceiver block 4012 is provided with an insertion aperture 401213.

The light passing hole 401211 extends from an inner surface of the first end of the transceiver stem 4012 to an outer surface of the first end of the transceiver stem 4012. The light-passing hole 401211 is used for emitting the first optical signal emitted from the laser chip 4021 out of the transceiver housing 401 and also for emitting the second optical signal emitted from the optical fiber adapter 404 into the transceiver housing 401.

In order to make the first optical signal emitted from the laser chip 4021 output to the outside of the transmission/reception housing 401 as much as possible, the second optical signal emitted from the optical fiber adapter 404 is made incident to the inside of the transmission/reception housing 401 as much as possible, and the light passing hole 401211 is aligned with the second lens 4025 and the second optical filter 4026.

The light window 401212 is provided corresponding to the light passing hole 401211, and the flat glass 407 is provided at the light window 401212. The flat glass 407 is sealed and welded to the optical window 401212. The flat glass 407 not only facilitates the emission of the first optical signal and the emission of the second optical signal, but also seals the transmission/reception housing 401.

The third circuit board 303 is inserted into the transceiver housing 401 through the insertion port 401213. In order to make the transceiver housing 401 a sealed housing, the upper cover 4011 is hermetically connected to the transceiver stem 4012, a flat window glass 407 is provided at the optical window at the first end of the transceiver stem 4012, and the third circuit board 303 is soldered to the insertion port 401213. Copper sheets are laid on the third circuit board 303 in the area corresponding to the insertion opening 401213, the transceiver tube seat 4012 is a metal transceiver tube seat, and the area corresponding to the insertion opening 401213 of the third circuit board 303 is welded with the insertion opening 401213 of the transceiver tube seat 4012 through soldering tin.

As can be seen in fig. 4-24, in some embodiments, the transceiver stem 4012 comprises a transceiver floor and a transceiver side panel that encloses a non-capped cavity with the transceiver floor.

The first end of the receiving and transmitting side plate is provided with a light through hole 401211 and a light window 401212, and the second end of the receiving and transmitting side plate is provided with an insertion port 401213.

The receiving and dispatching bottom plate includes a tube base body 40121, a storage groove 40122 and a first supporting protrusion 40123, and the concave degree of the storage groove 40122, the tube base body 40121 and the first supporting protrusion 40123 is sequentially weakened. That is, the storage groove 40122 is more recessed with respect to the stem body 40121 and the stem body 40121 is more recessed with respect to the first support protrusion 40123.

The socket body 40121 is an area of the receiving/transmitting bottom plate between the first supporting protrusion 40123 and the receiving/transmitting side plate except the storage groove 40122.

The header body 40121 has the light receiving chip 4028 provided thereon. Specifically, the header body 40121 is provided with a heat sink substrate on which the light receiving chip 4028 is provided. The light receiving chip 4028 is disposed corresponding to the first notch region 30321 of the third circuit board 303. Since the optical path of the second optical signal needs to be turned by the receiving turning prism, the upper surface of the light receiving chip 4028 must be far lower than the upper surface of the lithium niobate chip 4024. However, the upper surface of the third circuit board 303 is as high as the position of the upper surface of the lithium niobate chip 4024, so the light receiving chip 4028 cannot be directly placed on the third circuit board 303, but is placed on the header body 40121 through a heat sink substrate. That is, the light receiving chip 4028 is bonded to the heat sink substrate, which is bonded to the header body 40121.

The storage groove 40122 is located at the first end of the receiving/transmitting bottom plate and between the light passing hole 401211 and the first supporting protrusion 40123, and is used for placing a semiconductor refrigerator (TEC for short). The TEC and the light receiving chip 4028 are located at both sides of the first supporting protrusion 40123, respectively. The TEC is used to control the temperature of the laser chip 4021 so that the laser chip 4021 emits light of a specific wavelength.

If the TEC is directly placed on the header body 40121, the height of the first support projection 40123, and thus the positions of the insertion port 401213, the light-passing hole 401211, and the light-receiving chip 4028, must be increased in order to make the optical waveguide of the laser chip 4021 above the TEC and the optical waveguide of the lithium niobate chip 4024 on the same horizontal plane. When the position height of the light receiving chip 4028 is increased, it is necessary to increase the position height of the heat sink substrate on the lower side of the light receiving chip 4028, and therefore, it is not recommended to place the TEC on the header body 40121. When the position of the insertion opening 401213 is raised, the third circuit board 303 may not be inserted into the header body 40121 through the insertion opening 401213. Therefore, the TEC cannot be placed directly on the header body 40121. When the position height of the light passing hole 401211 is increased, it is also necessary to adjust the position height of the optical fiber adapter 404. Since the position of the fiber optic adapter 404 is fixed in height, the position of the light aperture 401211 is also fixed, and therefore the TEC cannot be placed directly on the header body 40121. In order to keep the optical waveguide of the laser chip 4021 above the TEC on the same horizontal plane as the optical waveguide of the lithium niobate chip 4024 and not to raise the height of the first support protrusion 40123, in some embodiments, the TEC is placed in the placement groove 40122 and the placement groove 40122 is more recessed relative to the header body 40121.

Because of poor thickness tolerance control of the TEC, the height difference between the light outlet of the laser chip 4021 and the input interface of the lithium niobate chip 4024 is large, and the first lens 4022 can only couple a small portion of light with a specific wavelength emitted by the laser chip 4021 into the lithium niobate chip 4024, so that coupling efficiency is low. To avoid this problem, in some embodiments, the TEC has a first ceramic substrate bonded thereto.

The first ceramic substrate is provided with a second ceramic substrate, and the second ceramic substrate is provided with a laser chip 4021 and a thermistor.

The first ceramic substrate can reduce the height difference between the light outlet of the laser chip 4021 and the input interface of the lithium niobate chip 4024, so that the light outlet of the laser chip 4021 and the input interface of the lithium niobate chip 4024 are located at the same horizontal plane as much as possible, and coupling efficiency is improved.

The first ceramic substrate is provided with a transfer circuit in addition to the second ceramic substrate, the first lens 4022, and the second optical filter 4026. The switching circuit is used for connecting the TEC, the laser chip 4021 and the thermistor with the third circuit board 303.

The second ceramic substrate is provided with a laser chip 4021 and a thermistor.

A thermistor, located near the laser chip 4021, is used to monitor the temperature change of the laser chip 4021.

The second ceramic substrate is provided with a circuit in addition to the laser chip 4021 and the thermistor. The circuit is used for connecting the laser chip 4021 and the thermistor with the switching circuit.

The first support protrusion 40123 is located on the stem body 40121. The first end of the first supporting protrusion 40123 is connected to the first end of the receiving/transmitting side plate, and the second end and the side edge of the first supporting protrusion 40123 are not connected to the receiving/transmitting side plate.

The first support protrusions 40123 are provided with second support protrusions 40124. The first end of the first support protrusion 40123 is connected to the first end of the socket body 40121, the second end of the first support protrusion 40123 is connected to the second support protrusion 40124, and the second support protrusion 40124 is located at the second end of the socket body 40121. The first support projection 40123 is provided with an isolator 4023, a second lens 4025, a third lens 4027, and a receiving turning prism 40210, and the second support projection 40124 is provided with a lithium niobate chip 4024.

The first support protrusions 40123 have a height less than or equal to the height of the second support protrusions 40124. Specifically, the thickness of the lithium niobate chip 4024 is about 500 μm, and the height of the second lens 4025 is 1 mm, that is, the difference in height between the center of the second lens 4025 and the lower surface of the second lens 4025 is 500 μm. In the process of assembling the optical module, the position of the second lens 4025 needs to be moved up and down, left and right, so that the second lens 4025 collimates the modulated optical signal modulated by the lithium niobate chip 4024 as much as possible. Therefore, the height of the first supporting projections 40123 where the second lens 4025 is located is lower than the height of the second supporting projections 40124 where the lithium niobate chip 4024 is located.

However, if the thickness of the lithium niobate chip 4024 is about 550 μm, since the height difference between the center of the second lens 4025 and the lower surface of the second lens 4025 is 500 μm, the height of the first supporting projection 40123 where the second lens 4025 is located is equal to the height of the second supporting projection 40124 where the lithium niobate chip 4024 is located.

The first supporting protrusion 40123 includes a first side plate and a second side plate, the first end of the first side plate is connected with the first end of the receiving/transmitting side plate, the second end of the first side plate is connected with the first end of the second side plate, the first side plate is connected with the first side wall of the storage groove 40122, and the second side plate is connected with the second side wall of the storage groove 40122. The connection area of the first side plate and the second side plate is disposed corresponding to the second notch area 30322 of the third circuit board 303, and the first side wall of the storage slot 40122 is connected to the second side wall of the storage slot 40122.

The first side plate is provided with a third lens 4027 and a receiving turning prism 40210, the first end of the second side plate is provided with an isolator 4023 and a second lens 4025, and the second end of the second side plate is provided with a second supporting protrusion 40124.

The first supporting protrusion 40123 has an L-shape. Specifically, the first side plate of the first supporting projection 40123 encloses an L-shaped supporting projection with the second side plate of the first supporting projection 40123.

Fig. 26 is a first optical path diagram of an optical module according to some embodiments. As can be seen in fig. 4-26, in some embodiments, the laser chip 4021 emits light with a specific wavelength, the first lens 4022 couples the light with the specific wavelength emitted by the laser chip to the lithium niobate chip 4024, the light with the specific wavelength is modulated by the lithium niobate chip 4024 to obtain a modulated optical signal, the modulated optical signal is collimated by the second lens 4025 to obtain a collimated optical signal, and the collimated optical signal is coupled to the optical fiber ferrule of the optical fiber adapter 404 through the fourth lens 4029 after passing through the second optical filter 4026. Wherein the light with the wavelength lambda 1 is the light with the specific wavelength.

As can be seen in fig. 4-26, in some embodiments, the optical fiber ferrule of the optical fiber adapter 404 emits a second optical signal, the second optical signal is collimated by the fourth lens 4029 to obtain a collimated optical signal, the collimated optical signal is reflected by the second optical filter 4026 to the third lens 4027, the second optical signal reflected by the second optical filter 4026 is coupled to the receiving turning prism 40210 by the third lens 4027, and the second optical signal is incident into the light receiving chip 4028 after being redirected by the receiving turning prism 40210.

The application provides an optical module, which comprises an optical transceiver component. The optical transceiver assembly comprises a transceiver housing and a third circuit board. The receiving and transmitting shell is provided with a light window for emitting or entering light signals at the first end, an inserting port for inserting a third circuit board at the second end, and an optical assembly inside the inserting port. The third circuit board is provided with a hollowed-out area. The first optical signal in the receiving and transmitting shell is emitted through the optical window, and the second optical signal in the optical fiber adapter is emitted into the receiving and transmitting shell through the optical window. The circuit board extends into the receiving and transmitting shell through the inserting opening. In order to ensure the tightness between the circuit board and the receiving and transmitting shell, a copper sheet is laid in the area of the circuit board corresponding to the insertion opening, the receiving and transmitting shell is a metal receiving and transmitting shell, and the circuit board is welded with the insertion opening of the receiving and transmitting shell, so that the tightness between the circuit board and the receiving and transmitting shell is ensured. The optical component comprises a laser chip, a first lens, a lithium niobate chip, a second lens, a second optical filter, a third lens, a receiving turning prism and a light receiving chip. The laser chip, the first lens, the second optical filter, the third lens, the receiving turning prism and the light receiving chip are all positioned at the first end of the receiving-transmitting shell, and the lithium niobate chip is positioned at the second end of the receiving-transmitting shell. The laser chip is a high-power DFB laser chip. The high-power DFB laser chip is used for emitting high-power light. And the first lens is positioned between the laser chip and the lithium niobate chip and is used for coupling high-power light to the lithium niobate chip. The lithium niobate chip is arranged corresponding to the hollowed-out area and comprises a substrate and a lithium niobate film, the optical loss is less than 10dB, and the lithium niobate chip is used for modulating high-power light to obtain a modulated optical signal. The lithium niobate thin film is paved on the substrate, and the thickness is smaller than 100 mu m. Because the lithium niobate chip is smaller and has higher integration precision, the lithium niobate chip has the advantages of low power consumption, low optical loss and the like compared with a silicon optical chip. The optical loss of the silicon optical chip is smaller than 11.2dB, and the optical loss of the lithium niobate chip is smaller than 10dB. Since the optical loss of the silicon optical chip is less than 11.2dB, in order for the optical module including the DFB laser chip+silicon optical chip combination to meet the requirement of the optical power of light emitted from the 50G PON, the optical power of light emitted from the DFB laser chip is required to be > 158mW. Since the optical loss of the lithium niobate chip is less than 10dB, in order for an optical module including the DFB laser chip+lithium niobate chip combination to meet the requirement of the optical power of light emitted from the 50G PON, the optical power of light emitted from the DFB laser chip is required to be > 80mW. The light power of the light emitted by the conventional DFB laser chip is less than 50mW, and the light power of the light emitted by the high-power DFB laser chip is less than 120mW. In the prior art, the light power of light emitted by the DFB laser chip is difficult to meet more than 120mW in a full-temperature state. Therefore, in order for the optical module to meet the optical power requirement of the light emitted by the 50G PON, the optical module can only use a combination of DFB laser chips and lithium niobate chips. And the second lens is positioned between the lithium niobate chip and the second optical filter and is used for collimating the modulated optical signals to obtain collimated optical signals. And the second optical filter is positioned between the laser chip and the third lens and is used for transmitting the collimated optical signals to the optical fiber adapter. And the third lens is positioned between the second optical filter and the receiving turning prism and is used for coupling the second optical signal reflected by the second optical filter to the receiving turning prism. And the receiving turning prism is positioned above the light receiving chip and is used for changing the second optical signal so as to reflect the second optical signal to the light receiving chip. In the application, the laser chip provides high-power light, the light loss of the lithium niobate chip is smaller than that of the silicon light chip, and the modulated light signal modulated by the lithium niobate chip meets the requirement of the light power of light emitted by the 50G PON.

Since (1) the first lens 402 may be not only a focusing lens, the first lens 4022 may also include a first sub-lens 40221 and a second sub-lens 40222, the first sub-lens 40221 is located between the laser chip 4021 and the isolator 4023, the second sub-lens 40222 is located between the isolator 4023 and the lithium niobate chip 4024, the first sub-lens 40221 is a collimating lens, and the second sub-lens 40222 is a focusing lens; (2) The second optical filter 4026 may include two 45 ° triangular prisms, where the hypotenuses of the two 45 ° triangular prisms are bonded, and one hypotenuse is coated with a filter film; the optical fiber transceiver also comprises a glass sheet, wherein one end of the glass sheet facing the optical fiber is plated with a light filtering film, and the glass sheet is fixed on the transceiver tube seat through a light filtering bracket; (3) The receiving turning prism 40210 may be connected to the third lens 4027 or disconnected from the third lens 4027. In some embodiments, not only the first light path diagram shown in fig. 26 is provided, but also a second light path diagram may be provided.

Fig. 27 is a second optical path diagram of an optical module according to some embodiments. As can be seen in fig. 27, in some embodiments, the laser chip 4021 emits light with a specific wavelength, the first sub-lens 40221 collimates the light with the specific wavelength emitted by the laser chip to obtain collimated light, the second sub-lens 40222 couples the collimated light to the lithium niobate chip 4024, the light with the specific wavelength is modulated by the lithium niobate chip 4024 to obtain a modulated optical signal, the modulated optical signal is collimated by the second lens 4025 to obtain a collimated optical signal, and the collimated optical signal is coupled to the optical fiber ferrule of the optical fiber adapter 404 through the fourth lens 4029 after passing through the second optical filter 4026.

As can be seen from fig. 27, in some embodiments, the optical fiber ferrule of the optical fiber adapter 404 emits a second optical signal, the second optical signal is collimated by the fourth lens 4029 to obtain a collimated optical signal, the collimated optical signal is reflected by the second optical filter 4026 to the third lens 4027, the second optical signal reflected by the second optical filter 4026 is coupled to the receiving turning prism 40210 by the third lens 4027, and the second optical signal is incident into the light receiving chip 4028 after being redirected by the receiving turning prism 40210.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and are not limiting thereof; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the corresponding technical solutions.

Claims

1. An optical module, comprising:

The third circuit board is provided with a hollowed-out area;

a first lens located between the laser chip and the lithium niobate chip;

and the receiving turning prism is positioned above the light receiving chip.

2. The optical module of claim 1, wherein the transceiver socket comprises a transceiver side plate and a transceiver bottom plate;

the receiving and transmitting side plate and the receiving and transmitting bottom plate enclose a cavity without a cover body, the first end is provided with the optical window and the light transmission hole, and the second end is provided with the insertion port;

The light transmission hole extends from the inner surface of the first end of the receiving and transmitting side plate to the outer surface of the first end of the receiving and transmitting side plate;

the receiving and transmitting bottom plate is provided with a tube seat body, a storage groove and a first supporting protrusion;

the first supporting protrusion is connected with the first end of the receiving and transmitting side plate, and the side edge and the second end are not connected with the receiving and transmitting side plate;

the concave degrees of the first supporting bulge, the tube seat body and the storage groove are deepened in sequence;

the light receiving chip is arranged on the tube seat body.

3. The light module of claim 2 wherein the first support protrusion comprises a first side plate and a second side plate;

the first side plate is connected with the first end of the receiving and transmitting side plate, the second end of the first side plate is connected with the second side plate, and the third lens is arranged on the first side plate;

the second side plate is provided with a second supporting bulge and the second lens;

the second supporting protrusions are arranged corresponding to the hollowed-out areas, and the lithium niobate chip is arranged on the second supporting protrusions.

4. A light module as recited in claim 3, wherein a height of the first support projection is less than or equal to a height of the second support projection.

5. A light module as recited in claim 3, further comprising a circuit board;

the circuit board comprises a first circuit board, a second circuit board and the third circuit board;

the first circuit board is connected with the second end of the second circuit board, and the second end is provided with a golden finger;

the first end of the second circuit board is connected with the second end of the third circuit board;

the first end of the third circuit board extends into the transceiver tube seat through the inserting port and comprises a first sub-circuit board and a second sub-circuit board;

the connection part of the first sub-circuit board and the second sub-circuit board is provided with a second notch area and the hollowed-out area;

the second sub-circuit board is provided with a first notch area, and is more sunken relative to the first sub-circuit board;

the first notch area is arranged corresponding to the light receiving chip;

the second notch area is arranged corresponding to the connecting area of the first side plate and the second side plate, and is closer to the golden finger of the third circuit board relative to the first notch area;

the hollowed-out area is provided with an opening, and the opening is arranged corresponding to the second supporting protrusion.

6. The optical module of claim 1, wherein the second optical filter comprises two 45 ° prisms, the hypotenuses of the two 45 ° prisms being bonded, one hypotenuse being coated with a filter film; it is also possible to include only one glass sheet, wherein the side of the glass sheet facing the optical fiber is coated with a filter film.

7. The optical module of claim 1, wherein the first lens is a focusing lens; or a collimating lens and a focusing lens.

8. The optical module of claim 1, wherein the receiving turning prism may or may not be connected to the third lens, and wherein the angle of the receiving turning prism is 41 ° to 43 °.

9. The optical module of claim 1, wherein the optical transceiver assembly further comprises a lens mount and a fiber optic adapter;

the lens fixing seat is internally provided with a fourth lens which is connected with the first end of the receiving and transmitting shell;

the optical fiber adapter is connected with the lens fixing seat;

the fourth lens is configured to couple an optical signal transmitted through the second optical filter to the optical fiber adapter, and is further configured to collimate a second optical signal incident by the optical fiber adapter and then inject the collimated second optical signal into the second optical filter.

10. The optical module of claim 1, wherein a TEC is disposed in the storage tank;

the TEC is provided with a first ceramic substrate;

the first ceramic substrate is provided with a second ceramic substrate, the first lens and the second optical filter;

the second ceramic substrate is provided with the laser chip and the thermistor;

the thermistor is used for monitoring the temperature change of the laser chip.