CN216817021U - Optical module - Google Patents

Abstract

The optical module comprises a laser chip, a heating assembly and a heat sink, wherein a laser array, a guide area and a semiconductor optical amplifier are arranged on the surface of the laser chip, the laser array at least comprises a first laser and a second laser, the output wavelengths of the first laser and the second laser are different, and light beams of the first laser or the second laser can be guided to an input optical path of the semiconductor optical amplifier through the guide area; the surface of the laser array is provided with the heating assembly, the heating assembly independently heats the laser array, the influence of heat on the semiconductor optical amplifier is reduced, and meanwhile, the heat sink can transfer the heat generated by the semiconductor optical amplifier out, so that the semiconductor optical amplifier is kept at a lower temperature; and the projection area of the laser array on the heat sink is hollowed to form a through hole, the through hole can realize thermal isolation between the laser array and the heat sink, and the heat dissipation effect of the heat sink on the laser array is weakened, so that the wavelength tuning of the laser array is effectively carried out.

Description

Optical module

Technical Field

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

Background

An Optical module serves as a photoelectric conversion device, a laser is one of key structures, and a Semiconductor Optical Amplifier (SOA) is cascaded behind the laser to amplify Optical power so as to improve output Optical power. To reduce the coupling loss between the tunable laser array and the SOA, the tunable laser array and the SOA are typically disposed on the same chip. In order to ensure maximum output of optical power, the entire chip should operate at a lower temperature.

When the tunable laser is heated and the harmonic wave is modulated, because the laser and the SOA are on the same chip, the SOA temperature is also increased, and the gain efficiency is further reduced.

SUMMERY OF THE UTILITY MODEL

The application provides an optical module to realize that the region that laser array was located can realize the effective tuning of wavelength through heating, and the region that semiconductor optical amplifier was located has guaranteed the high power light output of chip in keeping at the lower temperature. Because the temperature sensor is designed on the heater assembly, the working temperature of the laser can be accurately read, and the wave locking function is realized.

The optical module provided by the embodiment of the application comprises:

a circuit board;

a light emitting assembly electrically connected to the circuit board, comprising:

the surface of the laser chip is provided with a laser array, a guide area and a semiconductor optical amplifier, the laser array at least comprises a first laser and a second laser, and the output wavelengths of the first laser and the second laser are different; the guide area is used for changing the transmission direction of the light beam of the first laser or the second laser so as to guide the light beam of the first laser or the second laser to an input optical path of the semiconductor optical amplifier;

the heating assembly is arranged on the laser array and used for heating and monitoring the temperature of the laser array so as to realize wavelength tuning of the laser array;

the heat sink bears the laser chip, and the laser array is provided with through holes in a projection area on the heat sink.

In the optical module provided in the embodiment of the application, a laser array, a guide area and a semiconductor optical amplifier are arranged on the surface of a laser chip, the laser array at least comprises a first laser and a second laser, the output wavelengths of the first laser and the second laser are different, and the guide area is used for changing the light beam transmission direction of the first laser or the second laser so as to guide the light beam of the first laser or the second laser to an input optical path of the semiconductor optical amplifier; the surface of the laser array is provided with the heating assembly, the heating assembly independently heats the laser array for wavelength tuning, the influence of heat on the semiconductor optical amplifier in the wavelength tuning process is reduced, and meanwhile, the heat sink can transfer the heat generated by the semiconductor optical amplifier out, so that the semiconductor optical amplifier keeps a lower temperature, and the semiconductor optical amplifier amplifies laser signals with high gain; and the projection area of the laser array on the heat sink is hollowed to form a through hole, the through hole can realize thermal isolation between the laser array and the heat sink, the heat sink cannot transfer excessive heat of the laser array area, and the heat dissipation effect of the heat sink on the laser array is weakened, so that the wavelength tuning of the laser array is effectively carried out.

Drawings

In order to more clearly illustrate the technical solutions in the present disclosure, the drawings needed 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 can be obtained by those skilled in the art according to the drawings. Furthermore, the drawings in the following description may be regarded as schematic diagrams, and do not limit the actual size of products, the actual flow of methods, the actual timing of signals, and the like, involved in 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 a light module according to some embodiments;

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

FIG. 5 is a block diagram of an external appearance of a light emitting assembly according to some embodiments;

FIG. 6 is a detailed block diagram of a light emitting assembly according to some embodiments;

FIG. 7 is a perspective underside view of a light emitting assembly according to some embodiments;

FIG. 8 is a perspective view of a light emitting assembly according to some embodiments;

FIG. 9 is a cross-sectional structural view of a light emitting assembly according to some embodiments;

FIG. 10 is an exploded block diagram of a light emitting assembly according to some embodiments;

FIG. 11 is an exploded block diagram of a light emitting assembly according to some embodiments;

FIG. 12 is a block diagram of a heating component of a light emitting assembly according to some embodiments;

FIG. 13 is a view-down block diagram of a heat sink of a light emitting assembly according to some embodiments;

FIG. 14 is a block diagram under another perspective of a heat sink of a light emitting assembly according to some embodiments;

FIG. 15 is a schematic temperature diagram of various structures of a heating component of a light emitting assembly according to some embodiments when not in operation;

FIG. 16 is a schematic temperature diagram of various structures in operation of a heating component of a light emitting assembly according to some embodiments.

Detailed Description

Technical solutions in some embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present disclosure, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments provided by the present disclosure belong to the protection scope of the present disclosure.

Unless the context requires otherwise, throughout the description and the claims, the term "comprise" and its other forms, such as the third person's singular form "comprising" and the present participle form "comprising" are to be interpreted in an open, inclusive sense, i.e. as "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" and the like are intended to indicate that a particular feature, structure, material, or characteristic associated with the embodiment or example is included in at least one embodiment or example of the present disclosure. The schematic representations of the above terms are not necessarily referring to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be included in any suitable manner in any one or more embodiments or examples.

In the following, the terms "first", "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments of the present disclosure, "a plurality" means two or more unless otherwise specified.

In describing some embodiments, expressions of "coupled" and "connected," along with their derivatives, may be used. For example, the term "connected" may be used in describing some embodiments to indicate that two or more elements are in direct physical or electrical contact with each other. As another example, some embodiments may be described using the term "coupled" to indicate that two or more elements are in direct physical or electrical contact. However, the terms "coupled" or "communicatively coupled" may also mean that two or more elements are not in direct contact with each other, but yet still co-operate or interact with each other. The embodiments disclosed herein are not necessarily limited to the contents herein.

"at least one of A, B and C" has the same meaning as "A, B or at least one of C", both including the following combination of A, B and C: a alone, B alone, C alone, a and B in combination, a and C in combination, B and C in combination, and A, B and C in combination.

"A and/or B" includes the following three combinations: a alone, B alone, and a combination of A and B.

The use of "adapted to" or "configured to" herein is meant to be an open and inclusive language that does not exclude devices adapted to or configured to perform additional tasks or steps.

As used herein, "about," "approximately," or "approximately" includes the stated values as well as average values that are within an acceptable range of deviation for the particular value, as determined by one of ordinary skill in the art in view of the measurement in question and the error associated with measurement of the particular quantity (i.e., the limitations of the measurement system).

In the optical communication technology, light is used to carry information to be transmitted, and an optical signal carrying the information is transmitted to information processing equipment such as a computer through information transmission equipment such as an optical fiber or an optical waveguide, so as to complete information transmission. Because the optical signal has the passive transmission characteristic when being transmitted through the optical fiber or the optical waveguide, the information transmission with low cost and low loss can be realized. Further, since a signal transmitted by an information transmission device such as an optical fiber or an optical waveguide is an optical signal and a signal that can be recognized and processed by an information processing device such as a computer is an electrical signal, it is necessary to perform interconversion 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 electrical signal in the technical field of optical fiber communication. The optical module comprises an optical port and an electrical port, the optical module realizes optical communication with information transmission equipment such as optical fibers or optical waveguides and the like through the optical port, realizes electrical connection with an optical network terminal (such as an optical modem) through the electrical port, and the electrical connection is mainly used for realizing power supply, I2C signal transmission, data signal transmission, grounding and the like; the optical network terminal transmits the electric signal to the computer and other information processing equipment through a network cable or a 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 mainly 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-distance signal transmission, for example, signal transmission of several kilometers (6 kilometers to 8 kilometers), on the basis of which if a repeater is used, ultra-long-distance transmission can be theoretically achieved. Therefore, in a typical optical communication system, the distance between the remote server 1000 and the optical network terminal 100 may be 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 apparatuses: router, switch, computer, cell-phone, panel computer, TV set 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 device 2000 and the remote server 1000 is completed by the optical fiber 101 and the network cable 103; and the connection between the optical fiber 101 and the network cable 103 is completed by the optical module 200 and the optical network terminal 100.

The optical module 200 includes an optical port and an electrical port. The optical port is configured to connect with the optical fiber 101, so that the optical module 200 establishes a bidirectional optical signal connection with the optical fiber 101; the electrical port is configured to be accessed into the optical network terminal 100, so that the optical module 200 establishes a bidirectional electrical signal connection with the optical network terminal 100. The optical module 200 converts an optical signal and an electrical signal to each other, so that a connection is established between the optical fiber 101 and the optical network terminal 100. For example, an 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 an 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.

The optical network terminal 100 includes a housing (housing) having a substantially rectangular parallelepiped shape, 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 establishes a bidirectional electrical signal connection with the optical module 200; 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. The optical module 200 is connected to the network cable 103 via the optical network terminal 100. For example, the optical network terminal 100 transmits an electrical signal from the optical module 200 to the network cable 103, and transmits a signal from the network cable 103 to the optical module 200, so that the optical network terminal 100 can monitor the operation of the optical module 200 as an upper computer of the optical module 200. The upper computer of the Optical module 200 may include an Optical Line Terminal (OLT) and 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 structural diagram of an optical network terminal according to some embodiments, and fig. 2 only shows a structure of the optical module 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 PCB circuit board 105 disposed in the housing, a cage 106 disposed on a surface of the PCB circuit board 105, 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 projection such as a fin that increases a heat radiation area.

The optical module 200 is inserted into a cage 106 of the optical network terminal 100, the cage 106 holds the optical module 200, and heat generated by the optical module 200 is conducted to the cage 106 and then diffused by a heat sink 107. After the optical module 200 is inserted into the cage 106, an electrical port of the optical module 200 is connected to an electrical connector inside the cage 106, and thus the optical module 200 establishes a bidirectional electrical signal connection with the optical network terminal 100. Further, the optical port of the optical module 200 is connected to the optical fiber 101, and the optical module 200 establishes bidirectional electrical signal connection with the optical fiber 101.

Fig. 3 is a block diagram of a light module according to some embodiments, and 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, a circuit board 105 disposed in the housing, and an optical transceiver module.

The shell comprises an upper shell 201 and a lower shell 202, wherein the upper shell 201 is covered on the lower shell 202 to form the shell with two openings 204 and 205; the outer contour of the housing generally appears square.

In some embodiments of the present disclosure, the lower housing 202 includes a bottom plate and two lower side plates located at two sides of the bottom plate and disposed perpendicular to the bottom plate; the upper housing 201 includes a cover plate, and two upper side plates disposed on two sides of the cover plate and perpendicular to the cover plate, and is combined with the two side plates by two side walls to cover the upper housing 201 on the lower housing 202.

The direction of the connecting line of the two openings 204 and 205 may be the same as the length direction of the optical module 200, or may not be the same as the length direction of the optical module 200. For example, the opening 204 is located at an end (left end in fig. 3) of the optical module 200, and the opening 205 is also located at an end (right end in fig. 3) of the optical module 200. Alternatively, the opening 204 is located at an end of the optical module 200, and the opening 205 is located at a side of the optical module 200. Wherein, the opening 204 is an electrical port, and the gold finger of the circuit board 105 extends out of the opening 204 and is inserted into an upper computer (such as the optical network terminal 100); the opening 205 is an optical port configured to receive the external optical fiber 101 so that the optical fiber 101 is connected to an optical transceiver module inside the optical module 200.

The upper shell 201 and the lower shell 202 are combined to assemble the circuit board 105, the optical transceiver module and other devices in the shell, and the upper shell 201 and the lower shell 202 can form package protection for the devices. In addition, when the devices such as the circuit board 105 and the like are assembled, the positioning components, the heat dissipation components and the electromagnetic shielding components of the devices are convenient to arrange, and the automatic implementation production is facilitated.

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

In some embodiments, the optical module 200 further includes an unlocking component 203 located on an outer wall of a housing thereof, and the unlocking component 203 is configured to realize a fixed connection between the optical module 200 and an upper computer or release the fixed connection between the optical module 200 and the upper computer.

Illustratively, the unlocking members 203 are located on the outer walls of the two lower side plates of the lower housing 202, and include snap-fit members that mate with a cage of an upper computer (e.g., the 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 engaging member of the unlocking member 203; when the unlocking member 203 is pulled, the engaging member of the unlocking member 203 moves along with it, and the connection relationship between the engaging member and the upper computer is changed to release the engagement relationship between the optical module 200 and the upper computer, so that the optical module 200 can be drawn out from the cage of the upper computer.

The circuit board 105 includes circuit traces, electronic components, and chips, and the electronic components and the chips are connected together by the circuit traces according to a circuit design to implement functions of power supply, electrical signal transmission, grounding, and the like. The electronic components may include, for example, capacitors, resistors, transistors, Metal-Oxide-Semiconductor Field-Effect transistors (MOSFETs). The chip may include, for example, a Micro Controller Unit (MCU), a limiting amplifier (limiting amplifier), a Clock and Data Recovery (CDR) chip, a power management chip, and a Digital Signal Processing (DSP) chip.

The circuit board 105 is generally a rigid circuit board, which can also perform a bearing function due to its relatively rigid material, for example, the rigid circuit board can stably bear a chip; the rigid circuit board can also be inserted into an electric connector in the cage of the upper computer.

The circuit board 105 further includes a gold finger formed on an end surface thereof, the gold finger being composed of a plurality of leads independent of each other. The circuit board 105 is inserted into the cage 106 and electrically connected to an electrical connector in the cage 106 by gold fingers. The gold fingers may be disposed on only one side of the circuit board 105 (e.g., the upper surface shown in fig. 4), or may be disposed on both the upper and lower sides of the circuit board 105, so as to adapt to the situation where the requirement of the number of pins is large. The golden finger is configured to establish an electrical connection with the upper computer to achieve power supply, grounding, I2C signal transmission, data signal transmission and the like. Of course, a flexible circuit board is also used in some optical modules. Flexible circuit boards are commonly used in conjunction with rigid circuit boards to supplement the rigid circuit boards.

The optical transceiver module includes an optical transmitter module 300 and an optical receiver module 400. The light emitting assembly 300 serves to convert a received electrical signal into an optical signal, and the light receiving assembly 400 serves to convert a received optical signal into an electrical signal.

As shown in fig. 5, the light emitting assembly 300 includes a cover plate 310 and a cavity 320, wherein a light emitting device is disposed in the cavity 320, and the main light emitting device is a laser; in the signal transmission process, after receiving the electrical signal transmitted by the circuit board 105, the optical transmitter in the cavity 320 converts the electrical signal into an optical signal, and then the optical signal enters the optical fiber adapter and is transmitted to the outside of the optical module.

The light emitting assembly is provided with a packaging structure for packaging laser chips and the like, and the existing packaging structures comprise a coaxial packaging TO-CAN, a silicon optical packaging, a chip-on-board LENS assembly packaging COB-LENS and a micro-optical XMD packaging. The package is further divided into hermetic package and non-hermetic package, which provides a stable and reliable working environment for the laser chip on one hand and forms external electrical connection and optical output on the other hand.

Depending on the product design and process, the optical module may be packaged differently to make the light emitting assembly. The laser chip has vertical cavity surface light emitting and edge light emitting, and the different light emitting directions of the laser chip can influence the selection of the packaging form. The various packages have obvious technical differences, whether they are different from the structure or from the process, and those skilled in the art know that although different packages achieve the same purpose, different packages belong to different technical routes, and different packaging technologies do not give technical suggestions to each other.

The application discloses light emission part adopts the encapsulation of little optics form, and during the light that the optical chip sent got into the air promptly, set up devices such as lens, fiber adapter on optical path, couple to fiber adapter behind the light that sends the optical chip behind the lens, fiber adapter and fiber connection.

A light emitting device is arranged in the cavity 320, the main light emitting device is a laser, one of the types of the lasers is a wavelength tunable laser, and the wavelength tuning performance of the laser means that: parameters such as change speed and change precision of the output laser from one wavelength to another wavelength on a spectrum; the ideal laser wavelength tuning process should be fast and accurate. Wavelength tunable lasers include dfb (distributed Feedback laser) lasers, i.e. distributed Feedback lasers, the wavelength tuning mode of which is usually temperature tuning, and the tuning mechanism is as follows: the tunable laser is heated, the refractive index of the active region is changed along with the heating, and the output light moves towards the long wavelength direction, so that the wavelength tuning is realized.

In order to increase the wavelength tuning range, the laser is usually designed in a laser array form, and a certain number of DFB lasers are used to cover the transmission band, in this embodiment, the DFB laser array may include 16 DFB lasers, only one DFB laser is turned on each time, and the output wavelength is changed by adjusting the grating of the DFB laser through temperature, so as to cover all the wavelengths of the whole C band; in order to make 16 DFB lasers cover the entire wavelength band, it is necessary to have a temperature regulation range of 30 ℃ or more for each DFB laser.

In order to increase the optical power of the output signal of the laser, a semiconductor optical amplifier is usually adopted, single longitudinal mode light emitted from the DFB laser is used as input light of the semiconductor optical amplifier, high-energy-level electrons in an active area of the SOA are induced to transit to low-energy-level electrons, and meanwhile, the number of particles in the active area of the SOA is inverted by carriers, so that a gain condition is formed, and then optical amplification is realized, so that the output optical power is improved.

In order to reduce the coupling between the laser array and the semiconductor optical amplifier, in the embodiment of the present application, the laser array and the semiconductor optical amplifier are designed on the same chip, and the chip is defined as a laser chip. The laser array and the semiconductor optical amplifier generate heat during operation, and should operate at a relatively low temperature in order to ensure maximum output of optical power.

The light emitting assembly in the embodiment of the application comprises a heat sink 700 and a TEC800, the heat sink 700 is made of a material with good heat conductivity, such as tungsten copper, and the TEC800 comprises a cold surface and a hot surface, and the heat sink 700 is arranged on the cold surface of the TEC 800; the heat sink 700 may transfer heat generated by the laser array and the semiconductor optical amplifier to the outside of the package of the light emitting assembly through the TEC 800. And then the laser chip, particularly the laser array and the semiconductor optical amplifier are kept at lower temperature, and larger optical power output is ensured.

When the laser array is subjected to temperature tuning, the laser array needs to be heated to achieve the purpose of wavelength tuning, however, when the laser array is heated, because the laser array and the semiconductor optical amplifier are on the same chip, the working temperature of the SOA cannot be influenced, and the gain efficiency of the SOA on the output optical power is influenced; when the heat sink 700 conducts heat dissipation treatment on the SOA, the effectiveness of temperature tuning of the laser array is inevitably affected; therefore, when the laser array is subjected to temperature tuning, how to keep the SOA within a low working range, and meanwhile, the laser array can effectively perform wavelength tuning becomes a technical problem to be solved in the field. When the temperature of the laser is tuned, the SOA needs to be cooled to keep a low working range, and meanwhile, the laser array needs to be heated to tune the wavelength, so that the two methods are in a pair of contradiction, and a two-in-one scheme is needed to solve the technical problem.

Fig. 6 is a structure of a light emitting module according to an embodiment of the present application, and as shown in fig. 6, the light emitting module includes a heating module 500, a laser chip 600, and a heat sink 700, specifically, the laser chip 600 is disposed on a surface of the heat sink 700, and the heating module 500 is disposed on a surface of the laser chip 600, specifically, the heating module 500 locally heats the laser chip 600, that is, directly heats only a laser array region, and does not heat a semiconductor optical amplifier. FIGS. 7 and 8 are structural views of a light emitting module at different viewing angles, respectively; FIG. 9 is a cross-sectional view of a light emitting assembly; fig. 10 is an exploded structural view of a light emitting module.

The specific structure of the heating assembly 500 is as shown in fig. 12, the heating assembly 500 is used for independently heating the laser array to realize wavelength tuning, so as to reduce the influence of heat on the semiconductor optical amplifier in the wavelength tuning process; the surface of the heating component 500 is provided with a heater 510 and a temperature sensor 520, the heater 510 is arranged in the peripheral area, the temperature sensor 520 is arranged in the central area, the heater 510 is designed to be relatively thick and short, the temperature sensor 520 is designed to be relatively thin and long, the heater 510 can heat the laser array, the temperature sensor 520 can accurately monitor the temperature of the laser to be heated, and the wavelength of the laser to be tuned can be accurately adjusted to the target wavelength according to the corresponding relation between the temperature and the wavelength of the laser; as the heating component locally heats the laser chip 600, the driving circuit of the heating component 500 has high efficiency, the temperature of the laser changes quickly, and the response time of wavelength tuning is short, so that the wavelength can be tuned quickly; in addition to the aforementioned temperature sensor 520, the heating assembly 500 of the embodiment of the present application can realize fast and precise wavelength tuning. Wherein the heater 510 may be in the form of a heating resistor and the temperature sensor 520 may be in the form of a thermistor.

One end of the heater 510 is connected with a first power supply pad 540, one end of the temperature sensor 520 is connected with a second power supply pad 550, the other end of the heater and the other end of the temperature sensor are connected to the grounding pad 530, the first power supply pad 540 supplies power to the heater to ensure the normal work of the heater 510, and the second power supply pad 550 supplies power to the temperature sensor 520 to ensure the normal work of the temperature sensor 520.

The heating assembly 500 is arranged on the surface of the laser array area, so that the temperature of the laser can be effectively controlled to reach the required working wavelength, and meanwhile, the heating assembly 500 independently heats the laser array area, so that the influence of heat on the semiconductor optical amplifier can be reduced; the temperature sensor 520 can avoid the use of a wave locker, save space and be beneficial to the realization of small-sized optical module products.

It can be understood that, although the heating assembly heats the laser array region alone, because the laser chip has a small size, the heating assembly still affects the operating temperature of the semiconductor optical amplifier during operation, so that the temperature of the semiconductor optical amplifier is increased, and therefore in the embodiment of the present application, the heat dissipation treatment needs to be performed on the semiconductor optical amplifier region, so that the final temperature of the semiconductor optical amplifier is far lower than the final temperature of the semiconductor optical amplifier when the heat dissipation treatment is not performed.

The specific structure of the laser chip 600 is shown in fig. 6, the laser chip 600 includes a laser array 610, a guiding region 620 and a semiconductor optical amplifier 630, the guiding region 620 is designed between the laser array 610 and the semiconductor optical amplifier, the laser array 610 enters the semiconductor optical amplifier 630 through the guiding region 620, and the semiconductor optical amplifier amplifies incident light power to improve output light power. The laser array 610 can effectively tune the wavelength under the action of the heating component 500, and the semiconductor optical amplifier 630 is not directly affected by the heating component 500, thereby ensuring the gain effect of the semiconductor optical amplifier. The laser array 610 includes a plurality of lasers, the transmission directions of the output lights of the lasers are different, and since the input optical path of the semiconductor optical amplifier 630 is determined, in the implementation of the present application, the transmission direction of the light beam of the laser in the laser array 610 in the working state is changed through the guiding region 620, so as to guide the light beam to the input optical path of the semiconductor optical amplifier 630. The guiding region 620 may be in the form of an optical waveguide.

The heat sink 700 is used as a heat dissipation assembly, as can be seen from fig. 9 and 10, the heat sink 700 is hollowed, and the specific structure of the heat sink 700 is as shown in fig. 13 and 14, the laser array 610 is provided with a through hole 710 in the projection area of the heat sink 700, the laser array 610 is hollowed in the projection area of the heat sink 700 to form the through hole 710, and the through hole 710 can achieve thermal isolation between the laser array 610 and the heat sink 700, so that the heat sink 700 does not excessively transfer away heat required by temperature tuning of the laser array 610, and the effectiveness of temperature tuning is ensured. The heating assembly 500 is arranged on the surface of the laser array, the heating assembly 500 independently heats the laser array 610, the influence of heat on the semiconductor optical amplifier 630 in the wavelength tuning process is reduced, and meanwhile, the heat sink 700 can transfer the heat generated by the semiconductor optical amplifier 630 out, so that the semiconductor optical amplifier 630 is kept at a lower temperature.

In the embodiment of the present application, the laser array 610 is hollowed in the projection area of the heat sink 700, so that the heat sink 700 becomes a heat dissipation component of the semiconductor optical amplifier to a great extent, and the heat dissipation effect on the laser array 610 is limited, thereby ensuring the effectiveness of temperature tuning of the laser array and ensuring that the semiconductor optical amplifier works in a relatively low temperature range.

The two ends of the through hole 710 are respectively provided with a first support region 720 and a second support region 730, the first support region 720 is disposed at the corresponding end of the semiconductor optical amplifier 630, the second support region 730 is disposed at the corresponding end of the laser array 610, and as can be seen from fig. 13 and 14, the area of the first support region 720 is larger than that of the second support region 730, so that the thermal resistance between the first support region and the heat sink 700 is small, the thermal resistance between the second support region and the heat sink 700 is large, and further the semiconductor optical amplifier and the heat sink 700 have good thermal conduction, and the thermal conduction efficiency between the laser array 610 and the heat sink 700 is relatively low, so that the heat generated by the semiconductor optical amplifier 630 can be more transferred to the outside by the heat sink 700, so that the semiconductor optical amplifier is kept in a lower working range, and the heat in the laser array 610 region is less transferred to the outside by the heat sink 700, thus, the laser array 610 can be effectively heated to reach the target wavelength during temperature tuning.

When the laser array is temperature tuned, the first support region 720 can well transfer the heat of the semiconductor optical amplifier region to the outside of the light emitting component tube shell, so that the SOA is kept at a lower temperature, and the higher output of the optical power is realized; the arrangement of the through holes 710 can realize thermal isolation between the laser array 610 and the heat sink 700, the heat transfer efficiency of the heat sink 700 to the laser array 610 is low, and the thermal resistance between the second support area and the heat sink 700 is large, so that the influence of the heat transfer of the heat sink 700 is further ensured to be small when the temperature tuning is performed on the laser array, the temperature tuning can be effectively performed on the laser array, and then the tuning to the target wavelength is performed.

When the laser array does not need to be subjected to temperature tuning, the heat sink 700 can also be used for transferring heat to the laser array and the semiconductor optical amplifier, so that the heat generated by the laser array and the semiconductor optical amplifier is transferred to the outside of the tube shell of the light emitting component, and the output of larger optical power is ensured.

In order to further enlarge the hollowed area of the heat sink, further reduce the influence of the heat sink 700 on the temperature tuning of the laser array, and ensure the effectiveness of the temperature tuning, in the embodiment of the present application, the through holes 710 are respectively recessed toward the first support area 720 and the second support area 730 to obtain a third groove 760 and a fourth groove 770, and the projection area of the guide area 620 on the heat sink 700 is just located at the third groove 760, that is, the projection area of the guide area 620 on the heat sink 700 is also hollowed, so that the influence of the heat sink 700 on the temperature tuning of the laser array is reduced, and the effectiveness of the temperature tuning is ensured; the fourth groove 770 is exposed relative to one end of the laser chip, that is, one end of the laser chip is bridged over the fourth groove 770, and the effect after bridging is clearly shown in fig. 7 and 8; one end of the fourth groove 770 opposite to the laser chip is exposed, so that the corresponding end of the laser array can be prevented from contacting the heat sink 700, and the influence of the heat sink 700 on the temperature tuning of the laser array can be further reduced; two opposite sides of the through hole 710 are recessed upwards to form a first groove 740 and a second groove 750 respectively, that is, the through hole 710 is also arranged in a penetrating manner along the width direction of the heat sink 700, so that the projected area of the laser array on the heat sink is prevented from being in direct contact with the TEC800, and the influence of the heat sink 700 on the temperature tuning of the laser array is further reduced. Wherein it is understood that "width direction" refers to the width direction in the top view of the heat sink in fig. 13; the two opposite sides of the "two opposite sides of the through-hole 710 are recessed upward to form the first groove 740 and the second groove 750", respectively, refers to the sides where the two opposite long sides of the top view of the heat sink in fig. 13 are located.

In the embodiment of the application, the heating assembly 500 is arranged on the surface of the laser array, the heating assembly 500 independently heats the laser array 610, so that the influence of heat on the semiconductor optical amplifier 630 is reduced, and meanwhile, the heat sink 700 can transfer the heat generated by the semiconductor optical amplifier 630 out, so that the semiconductor optical amplifier 630 keeps a lower temperature, and the semiconductor optical amplifier amplifies laser signals with high gain; and the projection area of the laser array 610 on the heat sink 700 is hollowed to form the through hole 710, the through hole 710 can realize thermal isolation between the laser array 610 and the heat sink 700, the heat sink 700 cannot transfer excessive heat of the laser array area, the heat sink weakens the heat dissipation effect of the heat sink on the laser array, and therefore the wavelength tuning of the laser array is effectively carried out.

The light emitting module of the embodiment of the present application further includes a TEC800, the TEC800 is illustrated in fig. 11, and a semiconductor refrigerator (Thermo Electric Cooler) is made using a peltier effect of a semiconductor material. The peltier effect is a phenomenon in which when a direct current passes through a couple composed of two semiconductor materials, one end absorbs heat and the other end releases heat. The heavily doped N-type and P-type bismuth telluride are mainly used as semiconductor materials of the TEC, and the bismuth telluride elements are electrically connected in series and generate heat in parallel. The TEC comprises a number of P-type and N-type pairs (sets) connected together by electrodes and sandwiched between two ceramic electrodes; when current flows through the TEC, the heat generated by the current is transferred from one side of the TEC to the other side of the TEC, creating a "hot" side and a "cold" side on the TEC, which is the heating and cooling principle of the TEC.

The heat sink 700 is arranged on the surface of the TEC800 and is specifically in contact with the cold surface of the TEC, and the heat sink 700 transfers heat generated by the laser chip to the outside of the light emitting assembly tube shell through the TEC; the first support region 720 and the second support region 730 are respectively disposed on the surface of the TEC800, because two opposite sides of the through hole 710 are upwardly and concavely recessed to respectively form a first groove 740 and a second groove 750, and the through hole 710 is also disposed through the through hole along the width direction of the heatsink 700, the first support region 720 and the second support region 730 are disposed on the TEC like two brackets, because the area of the first support region 720 is larger than that of the second support region 730, and after the through hole is hollowed, the area of the first support region 720 is still larger than that of the second support region 730, so that the contact area between the first support region 720 and the TEC800 is larger than that between the second support region 730 and the TEC800, and then when the heatsink 700 contacts the TEC800, the area of the semiconductor optical amplifier corresponding region contacting the TEC800 is larger than that between the laser array corresponding region and the TEC800, and therefore, the heat transfer efficiency of the semiconductor optical amplifier of the TEC800 is higher than that of the laser array, that is, the TEC800 may transfer more heat generated by the semiconductor optical amplifier to the outside of the optical transmission module package, and the TEC800 may transfer less heat in the laser array region to the outside of the optical transmission module package, so that when the temperature tuning is performed on the laser array, the semiconductor optical amplifier may operate at a lower temperature, and simultaneously, the laser array may also perform effective temperature tuning to tune to a target wavelength.

In the embodiment of the present application, thermal simulation is performed on the technical solution of the present application, and the results of the thermal simulation are shown in fig. 15 and 16, where fig. 15 is a thermal simulation result when wavelength tuning is not required, and fig. 16 is a thermal simulation result when wavelength tuning is performed on a laser array. As shown in fig. 15, when wavelength tuning is not required, that is, when the heating element does not operate, the temperature of the semiconductor optical amplifier region is 22.2 ℃, and the temperature of the laser array region is distributed at 24.5 ℃, 28.2 ℃ and 28.4 ℃; when the wavelength tuning is performed on the laser array, that is, the heating element is operated, the temperature of the semiconductor optical amplifier region is 34.1 ℃, and the temperature distribution of the laser array region is 52.8 ℃, 61.7 ℃ and 61.8 ℃.

As described above, in order that 16 DFB lasers can cover the entire wavelength band, it is necessary to make each DFB laser have a temperature adjustment range of 30 ℃ or more. By integrating the thermal simulation result, when the TEC performs low-temperature control, the area where the laser array is located still has a temperature adjustment range of more than 30 ℃, and the wavelength range required to be realized by tuning is completely supported, the temperature coefficient of the DFB laser in the embodiment of the present application is 0.1nm/° c, and the area where the laser array is located still has a temperature adjustment range of more than 30 ℃, so that a wavelength tuning range of about 3nm can be realized, and the coverage of the entire transmission band can be realized.

As described above, although the heating element only heats the laser array region, since the laser chip has a small size, the heating element still affects the operating temperature of the semiconductor optical amplifier during operation, so that the temperature of the semiconductor optical amplifier is increased, in the embodiment of the present application, the heat dissipation processing needs to be performed on the semiconductor optical amplifier region, so that the final temperature of the semiconductor optical amplifier is far lower than the final temperature of the semiconductor optical amplifier when the heat dissipation processing is not performed; the comprehensive thermal simulation result shows that when the temperature of the semiconductor optical amplifier in the embodiment of the application is tuned, the temperature is only increased from 22.2 ℃ to 34.1 ℃, the increasing amplitude is small, and the semiconductor optical amplifier is kept in a low working range. It will be appreciated that if no heat sinking process is applied to the semiconductor optical amplifiers when the laser array is temperature tuned, the final temperature of the semiconductor optical amplifiers will tend to be greater than 34.1 ℃.

Therefore, the thermal simulation result verifies that the technical scheme provided by the embodiment of the application can meet the following requirements: when the temperature of the laser array is tuned, the area where the laser array is still in the temperature adjusting range of more than 30 ℃, so that the wavelength tuning requirement is met; at the same time, the semiconductor optical amplifier remains in a lower operating range.

The technical scheme provided by the application can not only realize that the semiconductor optical amplifier is kept in a lower working range, but also realize the wavelength tuning range of the laser array.

In the optical module provided by the embodiment of the application, the heating assembly is arranged on the surface of the laser array and independently heats the laser array, so that the influence of heat on the semiconductor optical amplifier in the wavelength tuning process is reduced, and meanwhile, the heat sink can transfer the heat generated by the semiconductor optical amplifier out, so that the semiconductor optical amplifier keeps a lower temperature, and the semiconductor optical amplifier amplifies laser signals with high gain; and the projection area of the laser array on the heat sink is hollowed to form a through hole, the through hole can realize thermal isolation between the laser array and the heat sink, the heat sink cannot transfer excessive heat of the laser array area, and the heat dissipation effect of the heat sink on the laser array is weakened, so that the wavelength tuning of the laser array is effectively carried out.

The application provides a two-in-one scheme, which can ensure that the semiconductor optical amplifier works in a lower temperature range, and can effectively change the temperature of the laser array so as to realize the purpose of wavelength tuning.

The above description is only for the specific embodiments of the present disclosure, but the scope of the present disclosure is not limited thereto, and any person skilled in the art will appreciate that changes or substitutions within the technical scope of the present disclosure are included in the scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims (10)

1. A light module, comprising:

a circuit board;

a light emitting assembly electrically connected to the circuit board, comprising:

the surface of the laser chip is provided with a laser array, a guide area and a semiconductor optical amplifier, wherein the laser array at least comprises a first laser and a second laser, and the output wavelengths of the first laser and the second laser are different; the guide area is used for changing the transmission direction of the light beam of the first laser or the second laser so as to guide the light beam of the first laser or the second laser to an input optical path of the semiconductor optical amplifier;

the heating assembly is arranged on the laser array and used for heating and monitoring the temperature of the laser array so as to tune the wavelength of the laser array;

the heat sink bears the laser chip, and the laser array is provided with through holes in a projection area on the heat sink.

2. The optical module of claim 1, wherein a first supporting region and a second supporting region are respectively disposed at two ends of the through hole, the first supporting region is disposed at a corresponding end of the semiconductor optical amplifier, the second supporting region is disposed at a corresponding end of the laser array, and an area of the first supporting region is larger than an area of the second supporting region.

3. The optical module of claim 1, wherein two opposing side faces of the periphery of the through hole are recessed upwardly to form a first recess and a second recess, respectively.

4. The optical module of claim 2, wherein the through holes are recessed into the first and second support regions to form third and fourth grooves, respectively, and the fourth groove is disposed exposed with respect to the laser chip.

5. The optical module of claim 1, wherein the heating assembly comprises a heater for heating the laser array and a temperature sensor for monitoring the laser chip temperature;

one end of the heater is connected with a power supply bonding pad, and one end of the temperature sensor is connected with the power supply bonding pad;

the other end of the heater and the other end of the temperature sensor are both connected to a grounding pad.

6. The light module of claim 4, wherein a projection area of the guide area on the heat sink coincides with the third groove.

7. The light module of claim 2, wherein the light emitting assembly further comprises:

and the TEC bears the heat sink, and the contact area of the first support region and the TEC is larger than that of the second support region and the TEC.

8. The optical module of claim 4, wherein the length of the laser chip is less than the length of the heat sink, and one end of the laser chip close to the semiconductor optical amplifier is aligned with the heat sink, and one end of the laser chip close to the laser array is bridged over the fourth groove.

9. The optical module of claim 1, wherein the semiconductor optical amplifier is not provided with a through hole in a projection area on the heat sink.

10. The optical module according to claim 4, wherein the heating assembly comprises a carrier plate, a heater is disposed on a peripheral region of a surface of the carrier plate, a temperature sensor is disposed on a middle region of the surface of the carrier plate, and the temperature sensor is disposed along a broken line.

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