CN118112728A

CN118112728A - Optical module

Info

Publication number: CN118112728A
Application number: CN202211529544.8A
Authority: CN
Inventors: 王洪义; 赵其圣; 王海山
Original assignee: Hisense Broadband Multimedia Technology Co Ltd
Current assignee: Hisense Broadband Multimedia Technology Co Ltd
Priority date: 2022-11-30
Filing date: 2022-11-30
Publication date: 2024-05-31

Abstract

The optical module provided by the application comprises a first circuit board and a tunable laser module, wherein the tunable laser module is electrically connected with the first circuit board; the tunable laser module comprises a packaging cavity and a second circuit board, and the first circuit board is electrically connected with the second circuit board; a wavelength selection component, piezoelectric ceramics and a phase shifter are arranged in the packaging cavity; simultaneously transferring a current driving chip and a monitoring chip which are originally arranged on a second circuit board to a ceramic substrate in the packaging cavity, enabling the current driving chip and the monitoring chip to be chips with one interface so as to reduce the size, and then realizing the conduction between the current driving chip and a heated object and between the monitoring chip and the monitored object through an analog switch so as to ensure the normal operation of each device; when the design size of the current driving chip and the monitoring chip is reduced, the current driving chip and the monitoring chip can be transferred to the ceramic substrate in the packaging cavity, so that the area of the second circuit board is reduced, and the size of the tunable laser module is reduced.

Description

Optical module

Technical Field

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

Background

With the development of new business and application modes such as cloud computing, mobile internet, video and the like, the development and progress of optical communication technology become more and more important. In the optical communication technology, the optical module is a tool for realizing the mutual conversion of optical signals, is one of key devices in optical communication equipment, and the transmission rate of the optical module is continuously improved along with the development of the optical communication technology.

Some coherent optical modules comprise a wavelength-tunable laser module, wherein the tunable laser module comprises a hard circuit board (a circuit board different from the optical module) and a flexible circuit board besides a packaging cavity for accommodating optical devices, and the tunable laser module is electrically connected with the optical module circuit board through the hard circuit board and the flexible circuit board; the hard circuit board has more electric chips and circuits on the surface, so that the hard circuit board has larger area, thereby causing the tunable laser module to have larger volume and being difficult to adapt to the scene of small space inside the optical module package.

Disclosure of Invention

The application provides an optical module, which is suitable for a scene with small internal space of optical module package by reducing the volume of a tunable laser module.

The optical module provided by the application comprises:

the surface of the first circuit board is provided with a first MCU;

a tunable laser module electrically connected to the first circuit board, comprising:

one side of the packaging cavity is provided with a connecting pin, and the inside of the packaging cavity is respectively provided with a functional electric chip set, a light emitting chip, a wavelength selection component phase shifter and a shifter;

the functional electric chip set comprises an analog switch, a current driving chip and a monitoring chip;

The wavelength selection component comprises a first etalon and a second etalon, and is used for selecting light with specific wavelength from the light beam emitted by the light emitting chip;

The shifter is arranged outside the first etalon and the second etalon and is used for changing the cavity length of the resonant cavity under the action of driving voltage;

The phase shifter is arranged between the first etalon and the second etalon and is used for tuning the cavity length of the resonant cavity according to an error signal, and the error signal is obtained according to the driving voltage and the output optical power;

the surface of the second circuit board is provided with a second MCU and a power conversion chip which are electrically connected with the connecting pins;

the second MCU is electrically connected with the first MCU and is used for outputting a first enabling control signal or a second enabling control signal to the analog switch;

the power supply conversion chip is electrically connected with the analog switch, the current driving chip and the monitoring chip and is used for supplying power to the analog switch, the current driving chip and the monitoring chip;

The analog switch is electrically connected with the second MCU, and is used for controlling the current driving chip to be conducted with the polling of the object to be heated according to the first enabling control signal, and is also used for controlling the monitoring chip to be conducted with the polling of the object to be monitored according to the second enabling control signal, wherein the object to be heated comprises the first etalon, the second etalon and the phase shifter, and the object to be monitored comprises the first etalon, the second etalon and the phase shifter.

The optical module comprises a first circuit board and a tunable laser module, wherein the tunable laser module is electrically connected with the first circuit board; the tunable laser module comprises a packaging cavity and a second circuit board; the side of the packaging cavity is provided with a connecting pin, and one end of the second circuit board is connected with the connecting pin in a welding way; simultaneously, the current driving chip and the monitoring chip which are originally arranged on the second circuit board are transferred to the ceramic substrate in the packaging cavity, the current driving chip and the monitoring chip are designed to be chips with one output interface, so that the size is reduced, and then the conduction between the current driving chip and a heated object and between the monitoring chip and the monitored object is realized through an analog switch, so that the normal operation of each device is ensured; when the design sizes of the current driving chip and the monitoring chip are reduced, the current driving chip and the monitoring chip can be transferred to a ceramic substrate in the packaging cavity, so that the area of the second circuit board is reduced, and the volume of the tunable laser module is reduced; the current driving chip and the monitoring chip are respectively provided with an output interface, so that the current driving chip and the monitoring chip are single-channel electric chips, and the size is small, so that more space inside the packaging cavity is avoided; specifically, a first MCU is arranged on a first circuit board, a second MCU is arranged on a second circuit board, the second MCU is electrically connected with the first MCU to realize the control of the first MCU on the second MCU, then the second MCU sends different first enabling control signals to an analog switch in different time slots, and the analog switch polls and controls the conduction of a current driving chip and a heated object according to the first enabling control signals, so that the current driving chip outputs current to the heated object to heat; the second MCU sends different second enabling control signals to the analog switch in different time slots, and the analog switch polls and controls the conduction of the monitoring chip and the monitored object according to the second enabling control signals, so that the monitoring chip collects the temperature of the surface of the monitored object and carries out temperature monitoring, and accurate tuning of wavelength is realized; the heated object comprises a first etalon, a phase shifter and a second etalon, and the monitored object also comprises the first etalon, the phase shifter and the second etalon; the analog switch controls the current driving chip to be conducted with the first etalon, the phase shifter or the second etalon according to the first enabling control signal so as to heat the first etalon, the phase shifter and the second etalon; in addition, the analog switch controls the monitoring chip to be conducted with the first etalon, the phase shifter or the second etalon according to the second enabling control signal so as to monitor the surface temperatures of the first etalon, the phase shifter and the second etalon, and therefore accurate tuning of the wavelength is achieved; light of a particular wavelength can be selected by the first and second etalons and then wavelength locked by the phase shifter. In combination with the above, the current driving chip and the monitoring chip are set to be chips with one output interface through the control function of the analog switch, so that the sizes of the current driving chip and the monitoring chip are reduced, the current driving chip and the monitoring chip are arranged in the packaging cavity, the area of the second circuit board is reduced, and the size of the tunable laser module is reduced, so that the tunable laser module is suitable for application scenes with small inner space of the optical module.

Drawings

In order to more clearly illustrate the technical solutions of the present disclosure, the drawings that need to be used in some embodiments of the present disclosure will be briefly described below, and it is apparent that the drawings in the following description are only drawings of some embodiments of the present disclosure, and other drawings may be obtained according to these drawings to those of ordinary skill in the art. Furthermore, the drawings in the following description may be regarded as schematic diagrams, not limiting the actual size of the products, the actual flow of the methods, the actual timing of the signals, etc. according to the embodiments of the present disclosure.

Fig. 1 is a connection diagram of an optical communication system according to some embodiments;

Fig. 2 is a block diagram of an optical network terminal according to some embodiments;

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

fig. 4 is an exploded view of a light module according to some embodiments;

Fig. 5 is an internal block diagram of an optical module according to some embodiments;

fig. 6 is a schematic diagram of a connection relationship between a tunable laser module of an optical module and an optical module circuit board according to some embodiments;

FIG. 7 is an exploded view of a tunable laser module of an optical module in connection with an optical module circuit board in accordance with some embodiments;

fig. 8 is a diagram of the external structure of a package cavity in a tunable laser module of an optical module according to some embodiments;

Fig. 9 is an exploded view of a package cavity in a tunable laser module of an optical module according to some embodiments;

fig. 10 is a diagram of the internal structure of a package cavity in a tunable laser module of an optical module according to some embodiments;

FIG. 11 is an exploded view of the internal structure of a package cavity in a tunable laser module of an optical module according to some embodiments;

Fig. 12 is a schematic side view of the internal structure of a package cavity in a tunable laser module of an optical module according to some embodiments;

Fig. 13 is an exploded view of the interior of a package cavity in a tunable laser module of an optical module according to some embodiments;

Fig. 14 is a partial block diagram of the interior of a package cavity in a tunable laser module of an optical module according to some embodiments;

Fig. 15 is a partial block diagram of the interior of a package cavity in a tunable laser module 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, low-cost, low-loss information transmission 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 according to some embodiments. 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 according to some embodiments, and fig. 2 only shows a structure of the optical network terminal 100 related to the optical module 200 in order to clearly show a 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 view of a light 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 module.

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). Or opening 204 is located at the end of light module 200 and opening 205 is located at the side of light module 200. The opening 204 is an electrical port, and the golden finger of the circuit board 300 extends out of the opening 204 and is inserted into a host computer (e.g., 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 an optical transceiver component 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 component are conveniently installed in the shell, 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 assembly are assembled, the positioning component, the heat dissipation component and the electromagnetic shielding component of the devices are convenient to deploy, 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 203 located outside the housing thereof, and the unlocking member 203 is configured to achieve a fixed connection between the optical module 200 and the host computer, or to release the fixed connection between the optical module 200 and the host computer.

Illustratively, the unlocking member 203 is located on the outer walls of the two lower side plates 2022 of the lower housing 202, with a snap-in member 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 (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 formed on an end surface thereof, the gold finger 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. The golden finger can be arranged on the surface of one side of the circuit board 300 (such as the upper surface shown in fig. 4) or on the surfaces of the upper side and the lower side of the circuit board 300, so as to adapt to the occasion with large pin number requirements. The golden finger is configured to establish electrical connection with the upper computer to achieve power supply, grounding, I2C signal transmission, data signal transmission 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 assembly includes a light emitting device configured to implement emission of an optical signal and a light receiving device configured to implement reception of the optical signal. Illustratively, the light emitting device and the light receiving device are combined together to form an integral light transceiving component.

The optical module provided by the embodiment of the application is a coherent optical module, and in one embodiment of the application is a silicon optical coherent optical module; the coherent optical module is an optical module which adopts coherent modulation at a transmitting end and adopts coherent technology at a receiving end for detection.

As shown in fig. 4, 5 and 6, the coherent optical module of the present application includes a circuit board 300, and a DSP chip 400, a coherent optical module 500 and a tunable laser module 600 are disposed on the surface of the circuit board 300.

The coherent optical assembly 500, in some embodiments, includes a silicon optical chip, a first optical port for receiving light emitted by the tunable laser module 600, a second optical port for emitting generated optical signals, and a third optical port for receiving external optical signals.

Because the silicon material adopted by the silicon optical chip is not an ideal laser chip luminescent material and cannot integrate the luminescent unit in the manufacturing process of the silicon optical chip, the silicon optical chip needs to provide light by an external light source; in some embodiments, the tunable laser module 600 is used as an external light source, and provides laser for the coherent light component 500 through the first optical port, the laser enters the inside of the coherent light component 500 and is split into a first light beam and a second light beam through a beam splitter built in the silicon optical chip, the first light beam is used as a light source of the transmitting end, and the second light beam is used as a local oscillator light beam for receiving light; modulating the electric signal output by the DSP chip 400 into a first light beam in the coherent light assembly 500, generating an optical signal carrying data, and transmitting the optical signal out through a second optical port; in some embodiments, the external optical signal enters the coherent optical assembly 500 through the third optical port, and is coherently mixed with the second optical beam, and after coherent mixing, the output photocurrent is greatly increased; after being amplified by a transimpedance amplifier in one embodiment of the present application, the electrical signal is fed to the DSP chip.

For convenience of distinction, the above-described circuit board 300 is referred to as a first circuit board.

The tunable laser module in the related art comprises a packaging cavity, a second circuit board and a flexible circuit board, wherein each electric chip and each circuit are arranged on the surface of the second circuit board, the area is large, and the volume of the tunable laser module is large.

In the embodiment of the application, the design sizes of the current driving chip and the monitoring chip on the second circuit board are reduced, so that the current driving chip and the monitoring chip are transferred to the inner position of the packaging cavity from the second circuit board, the area of the second circuit board is reduced, and the volume of the tunable laser module is further reduced. In some embodiments, the current drive chip and the monitor chip are provided inside the package cavity in the form of bare chips in order to reduce the design size of the current drive chip and the monitor chip in one embodiment of the present application.

As shown in fig. 5 and 6, the tunable laser module 600 includes a package cavity 600c, a second circuit board 600a, and a flexible circuit board 600b; each optical device and each electrical device are arranged in the packaging cavity 600c, the connecting pins 630 are arranged on the side edges, the bonding pads electrically connected with the connecting pins 630 are arranged on the surface of the second circuit board 600a, and the bonding pads electrically connected with the flexible circuit board 600b are also arranged, so that the packaging cavity is electrically connected with the second circuit board 600a through the connecting pins 630, the second circuit board 600a is electrically connected with one end of the flexible circuit board 600b, and the flexible circuit board 600b is electrically connected with the first circuit board, so that the tunable laser module 600 is electrically connected with the first circuit board.

As shown in fig. 7, the second circuit board 600a and the first circuit board are layered, the flexible circuit board 600b is bent, and two ends of the bent shape are respectively connected to the second circuit board 600a and the first circuit board, so as to realize electrical connection between the second circuit board 600a and the first circuit board; in some embodiments, a first MCU is disposed on the surface of the first circuit board, and a second MCU is disposed on the surface of the second circuit board 600a, and the second MCU is electrically connected to the first MCU, so that the first MCU controls the second MCU, and thus controls each structure in the tunable laser module 600.

As shown in fig. 8, the tunable laser module 600 includes a package cavity 600c, where the package cavity 600c includes a cover 610 and a housing 620, and a plurality of connection pins 630 are provided on a side of the package cavity, and an optical fiber adapter 640 is provided on an end of the package cavity. The plurality of connection pins 630 include a first pin (set as an instruction pin), a second pin (set as a power pin), a third pin (set as an instruction pin), and the like, and further include other pins such as a ground pin, and the like.

The cover plate 610 and the shell 620 are in cover connection to form a packaging cavity, and each optical element and each electrical chip are arranged in the packaging cavity; the tunable laser module 600 is electrically connected to the second circuit board 600a through the connection pins 630, specifically, one end of the connection pins 630 extends into the package cavity to be electrically connected to the electrical devices inside the package cavity, and the other end extends out of the package cavity to be electrically connected to the second circuit board 600 a; the optical fiber adapter 640 is disposed at the optical port and is used for transmitting the laser beam output by the tunable laser module 600.

In one embodiment of the present application, the surface of the second circuit board 600a is provided with corresponding pads, which are soldered with the connection pins 630, so as to electrically connect the package cavity 600c with the second circuit board 600 a.

In one embodiment of the present application, as shown in fig. 9, the case 620 includes a first side plate 621, a second side plate 622, and a substrate 623, and the first side plate 621, the second side plate 622, and the substrate 623 are combined together to form the case 620, and when the case 620 is separated into the side plate 621, the second side plate 622, and the substrate 623, each optical element and each electrical chip can be mounted on the surface of the substrate 623, and then the first side plate 621 and the second side plate 622 are assembled together, so that packaging is facilitated and damage to the optical element and the electrical chip can be prevented.

As shown in fig. 10-13, each optical element and each electrical chip are arranged in the packaging cavity, and TEC650 and support plate 670 are respectively arranged on the surface of substrate 623; the TEC650 is configured to adjust the internal temperature of the package cavity 600c by heating or cooling, so that the internal temperature of the package cavity 600c is maintained within a certain range, and each device is ensured to work normally; the surface of the supporting plate 670 is provided with a ceramic substrate 660, and the supporting plate 670 is used for supporting the ceramic substrate 660 and raising the height of the optical elements arranged on the surface of the ceramic substrate 660 so that the optical paths of the optical elements on the surface of the ceramic substrate 660 and the optical paths of the optical elements on the surface of the TEC650 are on the same horizontal line. The ceramic substrate 660 is disposed proximate to the fiber optic adapter 640, and the width of the ceramic substrate 660 is relatively wide with respect to the width of the TEC650, i.e., the width of the ceramic substrate 660 is greater than the width of the TEC 650.

The ceramic substrate 660 has a light splitter 661, an isolator 662, a converging lens 663, an optical power detector 664, an analog switch 665, a current driving chip 666, and a monitoring chip 667 on the surface thereof.

In some embodiments, each optical element disposed within the package cavity 600c includes a light-emitting chip 651, a collimating lens 652, a wavelength selective component, a mirror 656, a phase shifter 654, a shifter 655, a beam-splitting sheet 661, an isolator 662, and a converging lens 663.

Each of the electrical chips provided in the package chamber 600c includes an analog switch 665, a current driving chip 666, and a monitoring chip 667. The second MCU is electrically connected to the analog switch 665, the current driving chip 666, and the monitoring chip 667, respectively. The second circuit board 600a has a surface provided with a second MCU600a1, a power conversion chip 600a2, a TEC control circuit 600a3, and a lock wave control chip 600a4, respectively.

In some embodiments, the connection pins 630 include a first pin, a second pin, a third pin, etc., and the analog switch 665 inside the package cavity 600c is electrically connected with the second MCU600a1 through the first pin to receive the enable control signal output from the second MCU600a 1; the current driving chip 666 is electrically connected with the power conversion chip 600a2 through a second pin to obtain power supply; the monitoring chip 667 is electrically connected with the power conversion chip 600a2 through a third pin to obtain power supply; in combination with the above, the first pin, the second pin and the third pin respectively have the properties of an instruction pin, a power pin and an instruction pin; specifically, a golden finger is arranged on one side of the first circuit board, the golden finger comprises a plurality of pins, the golden finger comprises power supply pins, the upper computer supplies power to the optical module through the power supply pins, namely the optical module obtains power supply through the power supply pins, the power supply pins on the first circuit board are electrically connected with the power conversion chip 600a2 through the flexible circuit board and the second circuit board 600a, so that the power conversion chip 600a2 obtains power supply, then the current driving chip 666 is electrically connected with the power conversion chip 600a2 through the second pins, so that the current driving chip 666 obtains power supply, and the monitoring chip 667 is electrically connected with the power conversion chip 600a2 through the third pins, so that the monitoring chip 667 obtains power supply; the power conversion chip 600a2 converts the received voltage with a certain value into another voltage with a certain value, and outputs the voltages with different values to the device to be powered, specifically, the power conversion chip 600a2 supplies power to the second MCU600a1, the TEC control circuit 600a3, the lock wave control chip 600a4, the current driving chip 666 and the monitoring chip 667, and the power conversion chip 600a2 converts the received voltage into voltages with different values to supply power to the second MCU600a1, the TEC control circuit 600a3, the lock wave control chip 600a4, the current driving chip 666 and the monitoring chip 667 because the working voltage values required by the second MCU600a1, the TEC control circuit 600a3, the lock wave control chip 600a3, the current driving chip 666 and the monitoring chip 667 are different.

In the embodiment of the application, the current driving chip 666 and the monitoring chip 667 are arranged in the packaging cavity 600c, so that the number of the electric chips on the surface of the second circuit board 600a is reduced, and the area of the second circuit board 600a is reduced, so that the volume of the tunable laser module 600 is reduced; specifically, an analog switch 665 is further disposed in the package cavity 600c, and the analog switch 665 is electrically connected to the second MCU600a1, so as to receive the enable control signal output by the second MCU600a 1. In some embodiments, the second MCU600a1 outputs a first enable control signal to the analog switch 665 at time t1, the analog switch 665 controls the current driving chip 666 to be turned on with the first etalon 653a according to the first enable control signal, and then the current driving chip 666 outputs a current to the first etalon 653a to heat the heating resistor of the first etalon 653a for wavelength screening; at time t2, the second MCU600a1 outputs a second enable control signal to the analog switch 665, and the analog switch 665 controls the monitoring chip 667 to be conducted with the first etalon 653a according to the second enable control signal, and then the monitoring chip 667 collects the thermistor resistance value of the first etalon 653a, so as to monitor the surface temperature of the first etalon 653 a; at time t3, the second MCU600a1 outputs a third enable control signal to the analog switch 665, the analog switch 665 controls the current driving chip 666 to be turned on with the second etalon 653b according to the third enable control signal, and then the current driving chip 666 outputs a current to the second etalon 653b to heat the heating resistor of the second etalon 653b, so as to perform wavelength screening; at time t4, the second MCU600a1 outputs a fourth enable control signal to the analog switch 665, and the analog switch 665 controls the conduction between the monitoring chip 667 and the second etalon 653b according to the fourth enable control signal, and then the monitoring chip 667 collects the thermistor resistance value of the second etalon 653b, so as to monitor the surface temperature of the first etalon 653 a. In view of the above, in the embodiment of the application, the second MCU600a1 outputs different enable control signals to the analog switch 665 at each moment, the enable control signals are used for polling the on-current driving chip 666 and the heated object, so that the current driving chip 666 heats the heated object in a polling manner, the enable control signals are also used for polling the on-current monitoring chip 667 and the monitored object, so that the monitoring chip 667 monitors the temperature of the monitored object in a polling manner.

In some embodiments of the present application, the current driving chip 666 can be a multi-path power driving chip or a single-path power driving chip; in one embodiment of the present application, the current driving chip 666 is preferably a single-path power driving chip, and the single-path power driving chip has one output electric port, so that the current driving chip 666 is provided in the package cavity 600c with advantages due to the smaller size compared with the multi-path power driving chip (having a plurality of output electric ports); likewise, the monitoring chip 667 may be a multi-path power driving chip or a single-path power driving chip; in one embodiment of the present application, the monitor chip 667 is preferably a single-channel power driving chip, and the single-channel power driving chip has one output port, so that the monitor chip 667 is provided in the package cavity 600c with advantages due to the smaller size compared to the multi-channel monitor chip (having multiple output ports). In some embodiments of the present application, when the current driving chip 666 is a single-path power driving chip, when the analog switch 665 controls the current driving chip 666 to be turned on with the heating resistance wire of the first etalon 653a, it means that the current driving chip 666 is in an off state with other devices; similarly, since the monitor chip 667 is a one-way monitor chip, when the analog switch 665 controls the monitor chip 667 to be connected to the thermistor wire of the first etalon 653a, it means that the monitor chip 667 is disconnected from other devices.

In some embodiments, the TEC650 is provided with a light emitting chip 651, a collimating lens 652, a wavelength selecting component, a reflecting mirror 656, a phase shifter 654 and a shifter 655 on the surface, and in one embodiment of the present application, the light emitting chip 651 is obliquely arranged, so that the emitted light beam is prevented from returning into the light emitting chip 651, and further, a steering lens (the steering lens is used for deflecting the returned light, and further, avoiding returning into the light emitting chip 651) is avoided, so that the light path structure is simplified; the light beam emitted from the light-emitting chip 651 is collimated into parallel light by the collimating lens 652 and enters the wavelength selective component.

In an embodiment of the application, the wavelength selective assembly comprises a first etalon 653a and a second etalon 653b; the first etalon 653a and the second etalon 653b are used as wavelength selection components, and have the characteristics of small FSR and high filtering fineness, and can perform preliminary selection on a plurality of wavelengths existing originally, so that only a few wavelengths are emitted.

The resonant cavity of the tunable laser is long, and a plurality of cavity modes which can oscillate exist; the transmission spectrum of the filter only allows one cavity mold to have lower loss and form laser oscillation output; since the cavity mode is subject to temperature, stress, etc., and the output wavelength is related to the cavity mode, the output wavelength is shifted, and thus the output wavelength of the laser needs to be locked. In the embodiment of the present application, the wave is locked by the cooperation of the phase shifter 654 and the shifter 655, and in one embodiment of the present application, piezoelectric ceramics are used as the shifter 655; specifically, by sending a control signal to the wave-locking control chip 600a4 through the second MCU600a1, inputting a certain driving voltage to the shifter 655 through the control signal, so that the shifter shakes, the mirror 656 on the surface of the shifter 655 shakes, the cavity length changes, meanwhile, the optical power detector 667a detects the output optical power, and according to the driving voltage and the output optical power, an error signal is obtained by calculating the driving voltage and the output optical power, and then according to the error signal, the phase shifter 654 is driven to operate, and by changing the temperature of the phase shifter 654, the refractive index of the phase shifter 654 is changed, the optical length of the phase shifter 654 is changed, and then the cavity length of the resonant cavity is changed, so as to lock the cavity length of the resonant cavity, and accordingly the cavity mode of the resonant cavity is locked, and the wavelength is locked. The application monitors the change of the cavity length of the resonant cavity in real time through the shifter 655 to dynamically tune the cavity length change to lock the cavity mode and thereby lock the wavelength.

The tunable laser module 600 includes a resonant cavity, in the embodiment of the present application, the resonant cavity is formed from the light emitting end face of the collimating lens 652 to the light entering end face of the reflecting mirror 656, and a first etalon 653a, a phase shifter 654, and a second etalon 653b are disposed in the resonant cavity. The light-emitting chip 651 is used for emitting light in a wide wavelength range, amplifying the light beam gain, and emitting light which is divergent light; the collimating lens 652 is configured to collimate the divergent light beam emitted from the light emitting chip 651 into a parallel light beam, and then enter the first etalon 653a in the form of parallel light, and the wavelength that can pass through both the first etalon 653a and the second etalon 653b simultaneously is screened out, specifically, the first etalon 653a and the second etalon 653b are heated, and the desired wavelength (target wavelength) can be selected out by the vernier effect of both the first etalon 653a and the second etalon 653 b; the resonant cavity of the tunable laser is long, and a plurality of cavity modes which can oscillate exist; the transmission spectrum of the filter only allows one cavity mold to have lower loss and form laser oscillation output; since the cavity mode is subject to temperature, stress, etc., and the output wavelength is related to the cavity mode, the output wavelength is shifted, and thus the output wavelength of the laser needs to be locked. In the embodiment of the present application, the wave is locked by the cooperation of the phase shifter 654 and the shifter 655, and in one embodiment of the present application, piezoelectric ceramics are used as the shifter 655; specifically, by sending a control signal to the wave-locking control chip 600a4 through the second MCU600a1, inputting a certain driving voltage to the shifter 655 through the control signal, so that the shifter shakes, the mirror 656 on the surface of the shifter 655 shakes, the cavity length changes, meanwhile, the optical power detector 667a detects the output optical power, and according to the driving voltage and the output optical power, an error signal is obtained by calculating the driving voltage and the output optical power, and then according to the error signal, the phase shifter 654 is driven to operate, and by changing the temperature of the phase shifter 654, the refractive index of the phase shifter 654 is changed, the optical length of the phase shifter 654 is changed, and then the cavity length of the resonant cavity is changed, so as to lock the cavity length of the resonant cavity, and accordingly the cavity mode of the resonant cavity is locked, and the wavelength is locked. The application monitors the change of the cavity length of the resonant cavity in real time through the shifter 655 to dynamically tune the cavity length change to lock the cavity mode and thereby lock the wavelength.

The light-emitting chip 651 is used for emitting light beams and amplifying the gain of the light beams, and particularly the light beams emitted by the light-emitting chip 651 are divergent light beams; the divergent light beam emitted by the light emitting chip 651 is collimated by the collimating lens 652, then enters the wavelength selection component, wavelength is screened by the first etalon 653a and the second etalon 653b in the wavelength selection component, specifically, the first etalon 653a and the second etalon 653b are arranged at intervals to form a vernier etalon, FSRs (FREE SPECTRAL RANGE and free frequency spectrum ranges) of the first etalon 653a and the second etalon 653b are different, light waves which can pass through a wave band and are common to the first etalon 653a and the second etalon 653b can be screened based on the vernier principle, namely, when certain wavelengths in transmission spectrums of the two etalons coincide (i.e. are aligned), light with the specific wavelength can be selected, and finally screened light with the specific wavelength can pass through the first etalon 653a and the second etalon 653b; the use of a single etalon with limited filtering capability, the superposition of the transmission wavelengths using the first etalon 653a and the second etalon 653b, allows the transmission wavelengths to meet the requirements, and in combination with the above, it can be seen that wavelengths that can be simultaneously transmitted through both, i.e., coincident transmission spectra, can be screened by the first etalon 653a and the second etalon 653b, and then by using the phase shifter 654 and the shifter 655 to lock the wavelengths, wavelength drift of the light waves screened by the first etalon 653a and the second etalon 653b is avoided, thereby locking the wavelengths screened by the first etalon 653a and the second etalon 653 b.

In the embodiment of the present application, the first etalon 653a and the second etalon 653b observe a vernier effect, and the vernier effect is applied in the present application as follows: the light waves of the common passable wave band of the first etalon 653a and the second etalon 653b are screened out, so that the accuracy of the tunable laser is improved. When the peak wavelengths of the first etalon 653a and the second etalon 653b are just aligned, the longitudinal mode near the wavelength λ1 will be excited, and the output wavelength λ1 is the final wavelength selected, and it can pass through the first etalon 653a or the second etalon 653b; when the first etalon 653a and the second etalon 653b are simultaneously adjusted, the resonance peak moves at the same speed in a state of being held in the array, thereby achieving tuning of the output wavelength. It is assumed that in some embodiments the FSRs (FREE SPECTRAL RANGE ) of the first and second etalons are 200GHz and 300GHz, respectively, i.e., the vernier scale gaps are 200G and 300G, respectively. When the vernier graduation marks of the first etalon and the second etalon are aligned through temperature control, the corresponding wavelength light wave is selected; after the first etalon and the second etalon are subjected to superposition filtering, the FSR of the transmission spectrum is 600GHz, compared with the single etalon, the FSR of the first etalon 653a and the second etalon 653b is greatly widened after being combined, and as the FSR is in direct proportion to the tunable wavelength, the range of the tunable wavelength is increased after the FSR is widened; in combination with the above, the first etalon 653a and the second etalon 653b form a vernier etalon, the first etalon 653a and the second etalon 653b have respective filter curves, and by using vernier effect, the temperature of the first etalon 653a and the temperature of the second etalon 653b can be changed, the two filter curves can be selected to overlap the selected filter wavelength, the tuning speed can be increased, the tuning range can be increased, and the wavelength tuning accuracy and precision can be improved by using the vernier etalon.

In the embodiment of the present application, the first etalon 653a, the second etalon 653b and the phase shifter 654 are disposed on the surfaces of the partition plates, that is, the first etalon 653a, the second etalon 653b and the phase shifter 654 are connected to the TEC through the partition plates, and the arrangement of the partition plates can thermally isolate the first etalon 653a, the second etalon 653b and the phase shifter 654 from the TEC, so as to avoid affecting the accuracy of temperature tuning of the first etalon 653a, the second etalon 653b and the phase shifter 654.

In the embodiment of the present application, as shown in fig. 15, a first through hole is formed on the surface of the first etalon 653a, for passing light, and a first heating resistance wire and a first thermistor wire are respectively arranged at the periphery of the first through hole;

The first heating resistance wire is electrically connected with the multipath current driving chip and is used for heating the surface of the first etalon;

the first thermistor wire is electrically connected with the monitoring chip and is used for monitoring the temperature of the surface of the first etalon;

the surface of the second etalon 653b is provided with a second through hole for light to pass through, and the periphery of the second through hole is respectively provided with a second heating resistance wire and a second thermistor wire;

The second heating resistance wire is electrically connected with the multipath current driving chip and is used for heating the surface of the second etalon;

The second thermistor wire is electrically connected with the monitoring chip and is used for monitoring the temperature of the surface of the second etalon;

the surface of the phase shifter 654 is provided with a third through hole for light to pass through, and the periphery of the third through hole is respectively provided with a third heating resistance wire and a third thermistor wire;

The third heating resistance wire is electrically connected with the multipath current driving chip and is used for heating the surface of the phase shifter;

and the third thermistor wire is electrically connected with the monitoring chip and is used for monitoring the temperature of the surface of the phase shifter.

Specifically, the center of the first etalon 653a has a first through hole for the light beam to pass through, and the heating resistance wire 653a1 (i.e. the first heating resistance wire) and the thermistor wire 653a2 (i.e. the first thermistor wire) of the first etalon 653a are respectively arranged around the periphery of the first through hole, the thermistor wire 653a2 is close to the outer side, the width of a metal ring is narrower, the resistance is larger, and the resistance value changes more obviously with the temperature, so that the surface temperature of the first etalon 653a can be monitored, and the wavelength and the spectral characteristics can be directly reflected; the heating resistance wire 653a1 is used to heat the first etalon 653a, change the refractive index of the first etalon 653a, and further change the wavelength selected by the first etalon 653 a; the thermistor wire 653a2 is used for monitoring the temperature of the first etalon 653a, the monitoring chip collects the resistance value of the thermistor wire 653a2, then the monitored resistance value result is fed back to the second MCU, and the second MCU tunes the temperature of the first etalon 653a according to the received resistance value result of the thermistor wire 653a2, and further tunes the wavelength; specifically, a groove can be etched on the surface of the first etalon 653a, and a heating resistance wire and a thermistor wire are respectively arranged in the groove to form a heating resistance wire 653a1 and a thermistor wire 653a2; the heating resistance wire 653a1 is arranged at the periphery of the through hole, and the thermistor wire 653a2 is arranged at the periphery of the heating resistance wire 653a 1; the heating resistance wire 653a1 and the thermistor wire 653a2 are both arranged on the first etalon 653a and around the periphery of the first through hole; because the heating resistance wire 653a1 surrounds the periphery of the first through hole, the heating is faster, and the first etalon 653a1 is heated more uniformly, the first etalon 653a1 can be heated rapidly and uniformly by the heating resistance wire 653a1, so that the rapid tuning of the wavelength is realized; the thermistor wires 653a2 are arranged on the periphery of the heating resistor wires 653a1, so that the temperature of each point around the heating resistor wires can be sensed simultaneously, the temperature measurement precision is higher, and the temperature of the first etalon 653a can be measured more accurately; in combination with the above, by heating the first etalon 653a, the refractive index of the first etalon 653a is changed, so that the transmission spectrum of the first etalon 653a can be changed, and the filtered wavelength of the first etalon 653a is changed, so as to realize wavelength tuning, and then the heating resistor wire 653a1 and the thermistor wire 653a2 are both arranged on the first etalon 653a, so that the first etalon 653a can tune the wavelength rapidly and accurately. The principle of the second etalon 653b is the same as that of the first etalon 653a, and will not be described. Likewise, a third through hole is provided in the center of the phase shifter 654 for the light beam to pass through, and a heating resistor wire 6541 (i.e., the third heating resistor wire) and a thermistor wire 6542 (i.e., the third thermistor wire) of the phase shifter 654 are respectively provided around the periphery of the third through hole, the heating resistor wire 6541 being used for heating the phase shifter 654, and the thermistor wire 6542 being used for monitoring the temperature of the phase shifter 654. The phase shifter 654 is heated by the heating resistor wire 6541, the refractive index of the phase shifter 654 is changed, and the phase of the light wave selected by the etalon is changed, specifically, the first etalon 653a and the second etalon 653b are used for wavelength tuning of the light wave, in the embodiment of the present application, the wave is locked by the cooperation of the phase shifter 654 and the shifter 655, in a certain embodiment of the present application, piezoelectric ceramics is used as the shifter 655; specifically, by sending a control signal to the wave-locking control chip 600a4 through the second MCU600a1, inputting a certain driving voltage to the shifter 655 through the control signal to shake the shifter, the mirror 656 on the surface of the shifter 655 shakes, the cavity length changes, and at the same time, the output optical power is detected by the optical power detector 667a, an error signal is obtained according to the driving voltage and the output optical power, in a certain embodiment of the present application, the driving voltage and the output optical power are calculated to obtain the error signal, then the operation of the phase shifter 654 is driven according to the error signal, by changing the temperature of the phase shifter 654, to change the refractive index of the phase shifter 654, the optical length of the phase shifter 654 is changed, and thus the cavity length of the resonant cavity is changed, to lock the cavity length of the resonant cavity, and accordingly the cavity mode of the resonant cavity, and thus the wavelength. The application monitors the change of the cavity length of the resonant cavity in real time through the shifter 655 to dynamically tune the cavity length change to lock the cavity mode and thereby lock the wavelength.

In the embodiment of the present application, the wavelength selected by the first etalon 653a and the second etalon 653b is referred to as a first wavelength; the laser resonant cavity has a laser mode wavelength (i.e., resonant wavelength) supported by the laser resonant cavity, wherein the laser mode can be a longitudinal mode or a transverse mode, and the laser mode wavelength is related to the length of the resonant cavity; when the first wavelength is the lasing mode wavelength supported by the cavity, light at the first wavelength may oscillate within the cavity to obtain a positive net gain, ultimately forming a laser output. When the first wavelength is a wavelength supported by the resonant cavity, the light of the first wavelength oscillates in the resonant cavity, and when the first wavelength is not a wavelength supported by the resonant cavity, the light cannot oscillate in the resonant cavity and finally disappears in the resonant cavity.

As shown in fig. 14, in the embodiment of the present application, only one resistance wire is disposed around the through hole of the first etalon 653a, and in order to distinguish the resistance wire from the heating resistance wire or the thermistor wire, the resistance wire is referred to as a temperature control resistance wire, and then the first temperature control resistance wire 653a0, the second temperature control resistance wire 653b0, and the third temperature control resistance wire 6540 are disposed around the through holes of the first etalon 653a, the second etalon 653b, and the phase shifter 654, respectively; by providing only one resistive wire around the via, the dimensions of the first etalon 653a, the second etalon 653b, and the phase shifter 654 can be reduced, thereby freeing up space inside the package cavity 600c for placement of the analog switch 665, the current drive chip 666, and the monitor chip 667; in some embodiments of the present application, the current driving chip 666 and the monitoring chip 667 are provided inside the package cavity 600c in the form of a bare chip having a smaller size and the same function as the packaged chip. In some embodiments, analog switch 665 controls current drive chip 666 to output current to first temperature control resistance wire 653a0 through an output power port to temperature tune first etalon 653a according to the received first enable control signal; the analog switch 665 controls the monitoring chip 667 to be conducted with the first temperature control resistance wire 653a0 according to the received second enabling control signal, and further the temperature of the first temperature control resistance wire 653a0 is collected through the monitoring chip 667, so that the surface temperature of the first etalon 653a is monitored; the analog switch 665 controls the current driving chip 666 to output current to the second temperature control resistance wire 653b0 through the output electric port according to the received third enable control signal, so as to perform temperature tuning on the second etalon 653 b; the analog switch 665 controls the conduction of the monitoring chip 667 and the second temperature control resistance wire 653b0 according to the received fourth enabling control signal, and further collects the temperature of the second temperature control resistance wire 653b0 through the monitoring chip 667, so as to monitor the surface temperature of the second etalon 653 b; heating or monitoring the temperature of each device in different time slots in sequence; in some embodiments, it is assumed that the analog switch 665 heats the first temperature control resistance wire 653a0 within 0-80ms and collects the resistance value of the first temperature control resistance wire 653a0 within 80-100ms in 1s, and in combination with the above, the present application can conduct the analog switch 665 in a time sharing manner and further collect the resistance value or the heating of the first temperature control resistance wire 653a0 in a time sharing manner under the control of the second MCU600a 1.

In combination with the foregoing, in some embodiments, the current driving chip 666 and the monitoring chip 667 are disposed in the package cavity 600c in the form of bare chips, then the current driving chip 666 is configured as a chip with one output electric port, the monitoring chip 667 is configured as a chip with one monitoring interface, and the conduction between the current driving chip 666 and the heated object is controlled by polling the analog switch 665, or the conduction between the monitoring chip 667 and the monitored object is controlled by polling, so as to ensure the temperature tuning of the wavelength selection component and ensure the accuracy of the temperature tuning; meanwhile, in some embodiments, by disposing the first temperature control resistance wire 653a0, the second temperature control resistance wire 653b0, and the third temperature control resistance wire 6540 on the surfaces of the first etalon 653a, the second etalon 653b, and the phase shifter 654, respectively, the dimensions of the first etalon 653a, the second etalon 653b, and the phase shifter 654 may be reduced, thereby freeing up the internal space of the package cavity 600c to facilitate placement of the analog switch 665, the current driving chip 666, and the monitoring chip 667; in combination with these factors, it is feasible to locate the analog switch 665, the current driving chip 666, and the monitoring chip 667 within the package cavity 600c with the tunable laser module 600 unchanged in volume.

Meanwhile, the current driving chip 666 and the monitoring chip 667 are arranged in the packaging cavity 600c, the distance between the current driving chip 666 and the heated object (the first etalon 653a, the second etalon 653b and the phase shifter 654), the distance between the monitoring chip 667 and the monitored object (the first etalon 653a, the second etalon 653b and the phase shifter 654) are shortened, the working efficiency of the current driving chip 666 and the monitoring chip 667 and the response speed of the heated object and the monitored object are improved, and accurate tuning of wavelength is further achieved.

Meanwhile, when the current driving chip 666 and the monitoring chip 667 are arranged in the packaging cavity 600c, the number of connecting pins can be reduced by arranging the current driving chip 666 and the monitoring chip 667 with a single-way chip under the control action of the analog switch 665; specifically, when the multi-path current driving chip is adopted in the conventional scheme, the multi-path current driving chip (such as the three-path current driving chip) arranged on the surface of the second circuit board 600a needs to be electrically connected with the first etalon 653a, the second etalon 653b and the phase shifter 654 in the package cavity through 3 corresponding pins in the connection pins 630, and when the multi-path monitoring chip is adopted in the conventional scheme, the multi-path monitoring chip (such as the three-path monitoring chip) arranged on the surface of the second circuit board 600a needs to be electrically connected with the first etalon 653a, the second etalon 653b and the phase shifter 654 in the package cavity through 3 corresponding pins in the connection pins 630, and when the current driving chip 666 and the monitoring chip 667 are arranged in the package cavity 600c, the connection pins are omitted, so that the pin number is reduced; even if the analog switch 665, the current driving chip 666, and the monitoring chip 667 are provided in the package cavity 600c, the first pin, the second pin, and the third pin are added, but the number of connecting pins is still reduced as a result; therefore, in combination with the above, the number of connection pins can be reduced when the current driving chip 666 and the monitoring chip 667 are disposed in the package cavity 600c in the embodiment of the application.

The laser beam output from the resonant cavity is incident on the beam splitter 661, the beam splitter 661 is subjected to beam splitting treatment, and most of the laser beam as emitted light sequentially enters the isolator 662 and the converging lens 663, and enters the optical fiber adapter 640 after being converged by the converging lens 663 and is transmitted; a small portion of the laser beam is reflected as the monitoring light and enters the optical power detector 664, the optical power detector 664 converts the received monitoring light signal into an electrical signal, and the second MCU600a1 obtains the magnitude of the optical power value by analyzing the electrical signal. Specifically, the proportion of the monitoring light to the laser beam output from the resonator may be 1% to 2%. Wherein the isolator 662 is used to block the laser light output from the cavity from returning again into the cavity, causing crosstalk to the cavity.

In the embodiment of the application, the electrical chip originally arranged outside the packaging cavity is transferred into the packaging cavity, and particularly, the electrical chip is arranged inside the packaging cavity in the form of a bare chip, and the electrical chip is arranged inside the packaging cavity in the form of the bare chip because the size of the bare chip is smaller than that of the packaged chip; then, in combination with the foregoing, the ceramic substrate 660 is disposed close to the optical fiber adapter 640, the width of the ceramic substrate 660 is wider than the width of the TEC650, that is, the disposed width of the ceramic substrate 660 is greater than the disposed width of the TEC650, so that the surface of the ceramic substrate 660 has a blank area except for the light splitting sheet 661, the separator 662 and the converging lens 663, and thus each electrical chip can be disposed on the surface of the blank area; because the size of the bare chip is smaller, the area of the blank area is not required to be too large, so that the overall volume of the tunable laser module 600 is not greatly changed, and each electrical chip in the form of the bare chip can be arranged inside the tunable laser module 600.

Some electrical chips are arranged on the surface of the ceramic substrate 660, and bonding pads are arranged on the surface of the ceramic substrate 660, so that one ends of some electrical chips are provided with corresponding bonding pads, and are electrically connected with corresponding optical elements through the bonding pads, and the other ends of the electrical chips are electrically connected with the outside of the packaging cavity through the connecting pins 630.

In the embodiment of the present application, a second MCU600a1, a power conversion chip 600a2, a TEC control circuit 600a3 and a lock wave control chip 600a4 are disposed on the surface of a second circuit board 600 a. The ceramic substrate 660 has an analog switch 665, a current driving chip 666, and a monitor chip 667 on its surface. Wherein, the analog switch 665, the current driving chip 666 and the monitoring chip 667 are arranged near the light port, so as to reduce the influence of each electrical chip on the internal temperature of the packaging cavity as much as possible. In some embodiments, the electrical chips may optionally be provided in bare form within the interior void region of the package cavity.

In the embodiment of the application, bonding pads are laid on the surface of the ceramic substrate 660, bonding pads are arranged on the surface of each electrical chip, and the electrical chips are connected with each other through bonding wires through the bonding pads on the surface; if the current driving chip 666 is wire-bonded to the bonding pad on the surface of the ceramic substrate 660 through the bonding pad on the surface thereof, then the bonding pad on the surface of the ceramic substrate 660 is electrically connected to the connection pin 630, and is electrically connected to the power conversion chip 600a2 on the surface of the second circuit board 600a through the connection pin 630, so that the current driving chip 666 obtains power supply; the monitoring chip 667 is wired to the bonding pad on the surface of the ceramic substrate 660 through the bonding pad on the surface of the monitoring chip 667, then the bonding pad on the surface of the ceramic substrate 660 is electrically connected to the connection pin 630, and is electrically connected with the power conversion chip 600a2 on the surface of the second circuit board 600a through the connection pin 630, so that the monitoring chip 667 obtains power supply; the analog switch 665 is electrically connected to the second MCU600a1 through the connection pin 630, so that the analog switch 665 receives an enable control signal outputted from the second MCU600a1, controls the current driving chip 666 to be turned on with the object to be heated according to the enable control signal, or controls the monitoring chip 667 to be turned on with the object to be monitored according to the enable control signal.

The second MCU600a1 is electrically connected to the power conversion chip 600a2, the TEC control circuit 600A3, the lock wave control chip 600a4, the analog switch 665, the current driving chip 666, and the monitor chip 667 the TEC control circuit 600A3, the current driving chip 666, and the monitor chip 667 the lock wave control chip 600a4, respectively; the temperature of the first etalon 653a, the temperature of the second etalon 653b, the temperature of the phase shifter 654, the cavity length of the laser resonator and other information corresponding to the specific wavelength can be obtained from the lookup table; for convenience of the following description, the corresponding temperature in the lookup table is referred to as a reference temperature.

The power conversion chip 600a2, the input end obtains power supply from the upper computer through the pin, and the output end is respectively and electrically connected with the second MCU600a1, the TEC control circuit 600a3 and the wave locking control chip 600a4, the analog switch 665, the current driving chip 666 and the monitoring chip 667, and is used for supplying power to the second MCU600a1, the TEC control circuit 600a3 and the wave locking control chip 600a4, the analog switch 665, the current driving chip 666 and the monitoring chip 667; the second MCU600a1, the TEC control circuit 600A3, and the lock wave control chip 600a4, the analog switch 665, the current driving chip 666, and the monitoring chip 667 each have different operation voltages, for example, the voltage required for the TEC control circuit 600A3 is 1.5 to 2.5V, the current driving chip 666 supplies power to the light emitting chip at the 1.2V operation voltage, and the current driving chip 666 supplies power to the first etalon 653a and the second etalon 653b at the 3V operation voltage, so the power conversion chip 600a2 is used to convert the power supply voltage obtained from the circuit board 300 into the operation voltage required for each voltage chip, specifically, the power conversion chip 600a2 obtains the power supply voltage from the circuit board 300, which is typically 3.3V; specifically, a golden finger is disposed on the surface of one end of the circuit board 300, wherein the golden finger includes a power supply pin, and the upper computer supplies power to the optical module through the power supply pin, so that the optical module obtains power supply. The connection pin 630 includes a power pin, one end of the power pin is electrically connected to the power pin, and the other end of the power pin is electrically connected to the power conversion chip 600a2, so that the power conversion chip 600a2 obtains power from an upper computer, the power conversion chip 600a2 performs voltage conversion, and can input a voltage with a certain value and output a voltage with another certain value, so as to supply power to the second MCU600a1, the TEC control circuit 600a3, the lock wave control chip 600a4, the analog switch 665, the current driving chip 666 and the monitoring chip 667, for example, the power conversion chip 600a2 inputs a voltage with 3.3V to the power conversion chip 600a2 and outputs a voltage with another value, i.e. provides working voltages with different values to the second MCU600a1, the TEC control circuit 600a3, the lock wave control chip 600a4, the analog switch 665, the current driving chip 666 and the monitoring chip 667, respectively. The power conversion chip 600a2 is electrically connected to the second MCU600a1, so that the power conversion chip 600a2 can be turned off and on by the second MCU600a1, i.e., whether the power conversion chip 600a2 supplies power to the outside or not is controlled by the second MCU600a 1.

One end of the TEC control circuit 600a3 is electrically connected with the second MCU600a1, and the other end of the TEC control circuit is electrically connected with the TEC650, and is used for supplying power to the TEC650 through the second MCU600a 1; specifically, the second MCU600a1 controls the TEC control circuit 600A3 to adjust the heating or cooling current provided to the TEC650, so as to heat or cool the TEC650, and changes the temperature of the TEC650, so as to change the working temperature of the light emitting chip 651; a thermistor wire can be arranged on the surface of the TEC650, the temperature of the TEC650 and the working temperature of the light emitting chip 651 are further monitored by monitoring the resistance of the thermistor wire, and the second MCU600a1 is used for adjusting the heating or refrigerating current provided to the TEC650 by controlling the TEC control circuit 600A3, so that the temperature of the TEC650 and the working temperature of the light emitting chip 651 are changed.

A current driving chip 666, one end of which is electrically connected to the second MCU600a1, and the other end of which is electrically connected to the light emitting chip 651, the heating resistance wire 653a1 of the first etalon 653a, the heating resistance wire 6541 of the second etalon 653b, and the heating resistance wire 6541 of the phase shifter 654, respectively, specifically, the current driving chip 666 is electrically connected to the light emitting chip 651, the heating resistance wire 653a1 of the first etalon 653a, the heating resistance wire 653b of the second etalon 653b, and the heating resistance wire 6541 of the phase shifter 654 by wire bonding, so that the current driving chip 666 is used to controllably provide bias currents of different magnitudes to the light emitting chip 651 through the second MCU600a1, so that the light emitting chip 651 emits light beams under the bias current effect, and amplifies the gain of the light beams; and for controllably supplying different magnitudes of currents to the heating resistance wire 653a1 of the first etalon 653a through the second MCU600a1 to heat the first etalon 653a, changing the temperature of the first etalon 653a so that the temperature of the first etalon 653a reaches a reference temperature corresponding to a lookup table stored inside the second MCU600a1, thereby tuning the wavelength; and is configured to controllably provide different amounts of current to the heating resistance wire of the second etalon 653b through the second MCU600a1, so as to heat the second etalon 653b, and change the temperature of the second etalon 653b, so that the temperature of the second etalon 653b reaches a reference temperature corresponding to a lookup table stored in the second MCU600a1, thereby performing wavelength tuning; and is configured to controllably supply different amounts of current to the heating resistance wire 6541 of the phase shifter 654 via the second MCU600a1 to heat the phase shifter 654 and change the temperature of the phase shifter 654 to perform wavelength locking. In one embodiment of the present application, the current driving chip 666 has a plurality of power transmission ports, which are multi-channel current driving chips, to respectively provide currents with different magnitudes to the light emitting chip 651, the first etalon 653a, the second etalon 653b, and the phase shifter 654. In one embodiment of the present application, the current driving chip 666 has an output power port, which is a single-channel power supply chip; in the conventional technology, the current driving chip 666 is a multi-path power driving chip, and has a plurality of output electrical ports for respectively supplying power to the light emitting chip, the first etalon, the phase shifter and the second etalon, so that the design size of the multi-path power driving chip is larger; in the embodiment of the application, by combining the analog switch 665, the current driving chip 666 is provided with an output electric port, so that the design size of the current driving chip 666 is reduced, and the current driving chip 666 is arranged in the packaging cavity, so that the feasibility is provided.

A monitoring chip 667, one end of which is electrically connected with the second MCU600a1, and the other end of which is electrically connected with the thermistor wire 653a2 of the first etalon 653a, the thermistor wire 65342 of the second etalon 653b, and the thermistor wire 6542 of the phase shifter 654, respectively, for monitoring the resistance of the thermistor wire 653a2 of the first etalon 653a, the resistance of the thermistor wire of the second etalon 653b, the resistance of the thermistor wire 6542 of the phase shifter 654, and the optical power detector 664, respectively, and converting the monitored resistance of the thermistor wire 653a2 of the first etalon 653a into an electrical signal, The resistance value of the thermistor wire of the second etalon 653b, the resistance value of the thermistor wire 6542 of the phase shifter 654, and the electrical signal converted and generated by the optical power detector 664 are fed back to the second MCU600a1, the second MCU600a1 judges the current real-time temperature of the first etalon 653a according to the resistance value of the thermistor wire 653a2 of the first etalon 653a, re-tunes the temperature of the first etalon 653a by heating according to the relation between the current real-time temperature and the corresponding reference temperature stored in the second MCU600a1, so that the real-time temperature reaches the corresponding reference temperature stored in the second MCU600a1, tuning of wavelength is realized; likewise, the second MCU600a1 judges the current real-time temperature of the second etalon 653b according to the resistance value of the thermistor wire of the second etalon 653b, and retunes the temperature of the second etalon 653b by heating according to the relationship between the current real-time temperature and the corresponding reference temperature stored in the second MCU600a1, so that the real-time temperature reaches the corresponding reference temperature stored in the second MCU600a1, and wavelength tuning is achieved; likewise, the second MCU600a1 judges the current real-time temperature of the phase shifter 654 according to the resistance value of the thermistor wire 6542 of the phase shifter 654, and retunes the real-time temperature of the phase shifter 654 by heating according to the relationship between the current real-time temperature and the corresponding reference temperature stored in the second MCU600a1, so that the real-time temperature reaches the corresponding reference temperature stored in the second MCU600a1, thereby realizing the locking of the wavelength. In one embodiment of the present application, the monitor chip 667 has a plurality of monitor interfaces to electrically connect with the first etalon 653a, the second etalon 653b, and the phase shifter 654, respectively, so as to monitor the temperatures of the surfaces of the first etalon 653a, the second etalon 653b, and the phase shifter 654. In one embodiment of the present application, the monitoring chip 667 has a monitoring interface, which is a single channel monitoring chip; the monitoring chip in the prior art is a multi-path monitoring chip and is provided with a plurality of monitoring interfaces for respectively monitoring the temperatures of the surfaces of the first etalon, the phase shifter and the second etalon, so that the design size of the multi-path power supply driving chip is larger; in the embodiment of the application, by combining the analog switch 665, the monitoring chip 667 is provided with a monitoring interface, so that the design size of the monitoring chip 667 is reduced, and the possibility of arranging the monitoring chip 667 inside the packaging cavity is provided.

In combination with the above, when the wavelength is tuned, for example, the target wavelength is 1380nm, the light-emitting chip 651 outputs a wide spectrum light with each wavelength, then the light is collimated into parallel light by the collimating lens 652, and then enters the wavelength selecting component, the wavelength selecting component comprises a first etalon 653a and a second etalon 653b, and meanwhile, when the second MCU600a1 obtains the reference temperature with the wavelength 1380nm according to the internal lookup table, the corresponding first etalon 653a, the second etalon 653b and the phase shifter 654, then the second MCU600a1 provides current to the heating resistor wire of each of the first etalon 653a, the second etalon 653b and the phase shifter 654 through the current driving chip 666, so as to heat the first etalon 653a, the second etalon 653b and the phase shifter 653b, and enable the respective temperatures of the first etalon 653a, the second etalon b and the phase shifter 653a 1 to reach the reference temperature stored in the second MCU600a1 according to the internal lookup table, and simultaneously, the second MCU600a1 outputs current to the first etalon a, the second etalon 653b and the phase shifter 653b through the current driving chip 653b and the second etalon b, and the phase shifter 653b reach the real-time value of each of the first etalon b and the phase shifter 653b and the phase shifter 654 b reach the real-time value by the current to the current driving the first etalon b and the second etalon b and the corresponding temperature value of the second etalon b 653b and the corresponding temperature 1; meanwhile, in the embodiment of the present application, the wave is locked by the cooperation of the phase shifter 654 and the shifter 655, and in a certain embodiment of the present application, piezoelectric ceramics are used as the shifter 655; specifically, by sending a control signal to the wave-locking control chip 600a4 through the second MCU600a1, inputting a certain driving voltage to the shifter 655 through the control signal, so that the shifter shakes, the mirror 656 on the surface of the shifter 655 shakes, the cavity length changes, meanwhile, the optical power detector 667a detects the output optical power, and according to the driving voltage and the output optical power, an error signal is obtained by calculating the driving voltage and the output optical power, and then according to the error signal, the phase shifter 654 is driven to operate, and by changing the temperature of the phase shifter 654, the refractive index of the phase shifter 654 is changed, the optical length of the phase shifter 654 is changed, and then the cavity length of the resonant cavity is changed, so as to lock the cavity length of the resonant cavity, and accordingly the cavity mode of the resonant cavity is locked, and the wavelength is locked. The application monitors the change of the cavity length of the resonant cavity in real time through the shifter 655 to dynamically tune the cavity length change to lock the cavity mode and thereby lock the wavelength.

According to the application, by combining the analog switch, the current driving chip and the monitoring chip are arranged as a chip with one output interface, so that the sizes of the current driving chip and the monitoring chip are reduced, the current driving chip and the monitoring chip are arranged in the packaging cavity, the area of the second circuit board is reduced, and the volume of the tunable laser module is reduced, so that the tunable laser module is suitable for an application scene with small inner space of the optical module; meanwhile, as the distance between the electrical chip and the optical element is shortened, the working efficiency of the electrical chip and the response efficiency of the optical element are improved, and meanwhile, the number of connecting pins can be reduced.

The foregoing is merely a specific embodiment of the disclosure, but the protection scope of the disclosure is not limited thereto, and any person skilled in the art who is skilled in the art will recognize that changes or substitutions are within the technical scope of the disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims

1. An optical module, comprising:

the surface of the first circuit board is provided with a first MCU;

2. The optical module of claim 1, wherein the second circuit board surface is further provided with a TEC control circuit and a wave locking control chip;

The encapsulation cavity includes the optic fibre adapter, and inside is equipped with:

the TEC is arranged at one side relatively far away from the optical fiber adapter, and the surface of the TEC is respectively provided with the light emitting chip, the collimating lens, the wavelength selection component, the phase shifter and the shifter;

the ceramic substrate is arranged on one side relatively close to the optical fiber adapter, and the surface of the ceramic substrate is respectively provided with a light splitting sheet, an isolator, a converging lens, the analog switch, the current driving chip and the monitoring chip.

3. The optical module of claim 2, wherein the power conversion chip is electrically connected to the second MCU, the TEC control circuit, the lock wave control chip, the power driving chip, and the monitoring chip, respectively;

One end of the TEC control circuit is electrically connected with the second MCU, and the other end of the TEC control circuit is electrically connected with the TEC and is used for supplying power to the TEC;

and one end of the wave locking control chip is electrically connected with the second MCU, and the other end of the wave locking control chip is electrically connected with the shifter.

4. The optical module of claim 2, wherein the connection pins comprise a first pin, a second pin, and a third pin;

the analog switch is electrically connected with the second MCU through the first pin so as to receive an enabling control signal output by the second MCU;

The power supply driving chip is provided with an output electric port and is electrically connected with the power supply conversion chip through the second pin so as to obtain power supply and further heat the heated object;

The monitoring chip is provided with a monitoring interface and is electrically connected with the power conversion chip through the third pin so as to obtain power supply and further monitor the monitored object.

5. The optical module of claim 4, wherein the ceramic substrate surface is provided with bonding pads;

the surface of the power driving chip is provided with a first bonding pad, the first bonding pad is connected with one end of the bonding pad on the surface of the ceramic substrate in a wire bonding manner, and the other end of the bonding pad on the surface of the ceramic substrate is electrically connected with the second pin;

The surface of the monitoring chip is provided with a second bonding pad, the second bonding pad is connected with one end of the bonding pad on the surface of the ceramic substrate in a wire bonding mode, and the other end of the bonding pad on the surface of the ceramic substrate is electrically connected with the third pin.

6. The light module of claim 1 wherein the first etalon surface is provided with a first through hole for light to pass through;

the periphery of the first through hole is provided with a first heating resistance wire and a first thermistor wire respectively;

The surface of the second etalon is provided with a second through hole for light to pass through;

the periphery of the second through hole is provided with a second heating resistance wire and a second thermistor wire respectively;

the surface of the phase shifter is provided with a third through hole for light to pass through;

And a third heating resistance wire and a third thermistor wire are respectively arranged at the periphery of the third through hole.

7. The light module of claim 1 wherein the first etalon surface is provided with a first through hole for light to pass through;

a first temperature control resistance wire is arranged at the periphery of the first through hole;

A second temperature control resistance wire is arranged at the periphery of the second through hole;

And a third temperature control resistance wire is arranged at the periphery of the third through hole.

8. The light module of claim 2 wherein the shifter surface is provided with a mirror;

the tunable laser module comprises a resonant cavity, wherein one end face of the resonant cavity is the light emitting face of the collimating lens, and the other end of the resonant cavity is the light entering face of the reflecting mirror.

9. The optical module of claim 1, wherein the power driving chip and the monitoring chip are provided as bare chips.

10. The optical module of claim 1, wherein the first circuit board and the second circuit board are connected by a flexible circuit board.