CN112054848B

CN112054848B - Optical module

Info

Publication number: CN112054848B
Application number: CN202010941062.8A
Authority: CN
Inventors: 张强; 赵其圣
Original assignee: Hisense Broadband Multimedia Technology Co Ltd
Current assignee: Hisense Broadband Multimedia Technology Co Ltd
Priority date: 2019-06-17
Filing date: 2019-06-17
Publication date: 2021-06-04
Anticipated expiration: 2039-06-17
Also published as: CN112054848A; CN110233673A; CN110233673B

Abstract

The application discloses optical module belongs to optical device technical field. In this application, when the first LD and the second LD are simultaneously in an on state, the first driver compares a current value of the first backlight current fed back by the first PD with the first backlight current reference value, and further drives the first LD to emit light. When the first LD is turned on and the second LD is turned off, the first driver compares the current value of the first backlight current fed back by the first PD with the reference value of the second backlight current, and then drives the first LD to emit light. Because the first driver can compare the backlight current fed back by the first PD with different backlight current reference values according to the state of the LD, and further drive the first LD to emit light, compared with the related art in which only one backlight current reference value is used to drive the LD to emit light all the time, the method provided by the embodiment of the present application can effectively avoid the interference of another LD on the optical power of the LD, thereby ensuring the stability of the optical power output by the LD.

Description

Optical module

The application is a divisional application with the application date of 2019, 6 and 17, the application number of 201910523195.0 and the patent name of optical module.

Technical Field

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

Background

A laser and a driver may be included in the optical module. In general, a laser may include an LD (laser diode) and a PD (photo detector). The driver provides working current for the LD of the laser, and the LD outputs light under the action of the working current. Most of the light output from the LD will be emitted along the emitting direction, which is called front light, and a very small part of the light will be emitted to the PD along the opposite direction of the emitting direction, which can be called back light. The PD may convert the received backlight into a backlight current and feed the backlight current back to the driver. Since the ratio of the front light to the backlight is constant, the magnitude of the backlight current may reflect the optical power of the front light output by the LD. Based on this, the driver can monitor the light power of the front light output by the LD by monitoring the magnitude of the backlight current, and when the magnitude of the backlight current is monitored to be not in accordance with the reference value, the driver can ensure the stability of the light power of the front light output by the LD by adjusting the magnitude of the output working current.

Fig. 1 is a schematic diagram of an optical path of a laser in an OLT optical module of a dual-rate coexistence type provided in the related art. As shown in fig. 1, the optical assembly includes two lasers, a first laser 101 and a second laser 103. The two lasers are packaged in a shell, and the emergent directions of the light rays of the two lasers are 90 degrees. When the two lasers are turned on simultaneously, the front light of the second laser 103 is coupled with the front light of the first laser 101 after passing through the filter 102, and then enters the optical fiber for transmission.

However, since the filter 102 cannot achieve 100% transmission, a small portion of the front light of the second laser 103 is reflected by the filter 102 and then irradiated onto the housing, and is reflected again by the housing and then irradiated onto the PD in the first laser 101. Since the backlight current fed back to the driver by the PD of the first laser 101 will directly affect the output power of the first laser 101, it can be seen that in case of the first laser 101 and the second laser 103 being simultaneously turned on, the second laser 103 will cause interference to the output power of the first laser 101.

Disclosure of Invention

The embodiment of the application provides an optical module, which can be used for solving the problem that when two lasers in the optical module are simultaneously started, the output power of the lasers is unstable due to mutual interference. The technical scheme is as follows:

in a first aspect, an optical module is provided, where the optical module includes a first laser diode LD, a second LD, a first backlight detector PD, a second PD, and a first driver, and the first LD and the first PD are both connected to the first driver;

the first driver is used for driving the first LD to emit light, and the first PD is used for feeding back a first backlight current to the first driver according to the received light;

when the first LD and the second LD are in an on state at the same time, the first driver is used for comparing the current value of the first backlight current with a first backlight current reference value so as to drive the first LD to emit light;

when the first LD is in an open state and the second LD is in a close state, the first driver is used for comparing the current value of the first backlight current with a second backlight current reference value so as to drive the first LD to emit light;

the second backlight current reference value is different from the first backlight current reference value.

In a second aspect, an optical module is provided, where the optical module includes a first laser diode LD, a second LD, a first backlight detector PD, a second PD, and a first driver, the first LD and the first PD are respectively connected to the first driver, and the first driver drives the first LD to emit light according to a feedback value of the first PD;

when the first LD and the second LD are simultaneously in an on state and the optical powers of the first LD and the second LD are both stable, the current value fed back by the first PD and received by the first driver is a first current value;

when the first LD is in an on state and the second LD is in an off state, and the optical power of the first LD is stable, the current value fed back by the first PD and received by the first driver is a second current value, and the second current value is different from the first current value.

The beneficial effects brought by the technical scheme provided by the embodiment of the application at least comprise:

in this embodiment, when the first LD and the second LD are simultaneously in the on state, the first driver compares a current value of the first backlight current fed back by the first PD with a first backlight current reference value, so as to drive the first LD to emit light. When the first LD is turned on and the second LD is turned off, the first driver compares the current value of the first backlight current fed back by the first PD with the reference value of the second backlight current, so as to drive the first LD to emit light. Because the first driver can compare the backlight current fed back by the first PD through different backlight current reference values according to the state of the LD, and then drive the first LD to emit light, compared with the prior art in which only one backlight current reference value is used to drive the LD to emit light all the time, the scheme provided by the embodiment of the application adopts two backlight current reference values to drive the first LD to emit light, and when the second LD is turned on, the light interference factor of the second LD on the first PD can be considered, and the influence on the light output power of the first LD can be avoided through the scheme, so that the stability of the light power output by the first LD is ensured.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic optical path diagram of an OLT optical module of a dual-rate coexistence type according to an embodiment of the present application;

fig. 2 is a schematic diagram of an APC closed loop of an optical module provided in an embodiment of the present application;

fig. 3 is a schematic diagram of an optical module provided in an embodiment of the present application;

fig. 4 is a three-dimensional schematic diagram of an optical module provided in an embodiment of the present application;

fig. 5 is a structural diagram of an optical module in an optical module according to an embodiment of the present disclosure;

fig. 6 is a schematic diagram of another optical module provided in an embodiment of the present application.

Detailed Description

To make the objects, technical solutions and advantages of the present application more clear, embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

Before explaining the embodiments of the present application in detail, the APC closed-loop mechanism of the optical module will be briefly described.

As shown in fig. 2, one LD201, one PD202 and one driver 203 in the optical module may form a closed loop system. Wherein, the LD201 and the driver 203 are connected.

The driver 203 may output a bias current to the LD201, and the LD201 emits light by the bias current. Most of the light emitted from the LD201 exits along the exiting direction, and this light may be referred to as front light. Another very small portion of the light will strike the PD202 in the opposite direction of the outgoing direction, and this portion of the light may be referred to as a backlight.

The PD202 may receive the backlight emitted from the LD201 and feed back a backlight current to the driver 203 according to the received backlight. Since the ratio of the front light to the backlight is constant, the driver 203 can determine the optical power of the front light according to the magnitude of the backlight current and the ratio between the front light and the backlight after receiving the backlight current. Based on this, the driver 203 may compare the current value of the backlight current with the current reference value after receiving the backlight current. If they are the same, it indicates that the optical power of the front light output by the LD201 is satisfactory. If the current value of the backlight current is smaller than the reference current value, it indicates that the light power of the front light output by the LD201 is smaller than the required light power, and at this time, the driver 203 may adjust the magnitude of the output bias current according to the difference between the current value of the backlight current and the reference current value, and further drive the LD201 to emit light, so that the light power of the front light output by the LD201 is kept stable.

Illustratively, when the LD201 has a reduced tilt efficiency due to a temperature increase or other factors, the optical power of the front light output by the LD201 will be reduced without changing the bias current output by the driver 203. Depending on the ratio between front light and backlight, the corresponding backlight may also be reduced. Accordingly, the backlight current fed back to the driver 203 by the PD202 according to the received backlight will also decrease. The driver 203 determines that the backlight current decreases by comparing the current value of the backlight current with the reference current value after receiving the backlight current, and thus determines that the light power of the front light output from the LD201 decreases. In this case, the driver 203 increases the output bias current according to the difference between the current value of the backlight current and the reference current value, the LD201 emits light under the drive of the increased bias current, and both the output front light and the backlight increase, so that the backlight current fed back by the PD202 also increases. After the driver 203 receives the backlight current fed back by the PD202 again, it may continue to compare the backlight current fed back by the PD202 with the reference current value by the above-mentioned method, until the current value of the increased backlight current is consistent with the reference current value, and then stop increasing the bias current, so that the light power of the front light is stabilized at the target setting value.

However, for a dual-rate coexistence 10G EPON OLT optical module or a Combo PON OLT optical module, there are two lasers inside the optical module, and each laser includes a set of LD and PD. In this case, when only one laser is turned on, the output power of the turned-on laser is not affected. However, when the two lasers are turned on simultaneously, as shown in fig. 1, when the front light of the LD of the second laser is incident on the filter, most of the light passes through the filter, and a small amount of the light may be reflected by the filter and irradiated onto the housing, and then reflected by the housing and incident on the PD of the first laser. In this way, the PD of the first laser may receive not only the backlight of the LD of the first laser but also a part of the light of the LD of the second laser. In this case, based on the above description of the APC closed-loop mechanism, although the optical power of the front light of the LD of the first laser is not changed, the PD of the first laser receives a portion of the backlight beam that is doped with the LD of the second laser, and thus the backlight current fed back by the PD of the first laser increases. Based on this, after receiving the backlight current fed back by the PD of the first laser, the driver erroneously determines that the optical power of the front light of the LD of the first laser is increased according to the backlight current, so that the output bias current is adjusted to be small according to the difference between the current value of the backlight current and the reference current value. Thus, the optical power of the front light, which is not originally increased, is reduced. It follows that the optical power of the front light of the LD of the first laser is reduced, that is, the optical power of the first laser is reduced, due to the interference of the light emitted from the LD of the second laser. Also, in some cases, the second laser may also be affected by the first laser.

To solve the problems in the related art, an embodiment of the present application provides an optical module. In the embodiment of the present application, for any one LD in the optical module, two different backlight current reference values may be set in the optical module for the LD. When the LD and the other LD are in the on state at the same time, the current fed back by the PD corresponding to the LD is compared according to the reference value of the backlight current, and the LD is driven to emit light. The other backlight current reference value is a reference value when only the LD is turned on, that is, when only the LD is turned on, the current fed back by the PD corresponding to the LD may be compared according to the other backlight current reference value, and the LD is driven to emit light. Thus, according to the state of the LD, the LD can be driven to emit light by different backlight current reference values, and compared with the method that only one backlight current reference value is adopted to drive the LD to emit light all the time in the related art, the method provided by the embodiment of the application can effectively avoid the interference of another LD on the optical power of the LD, thereby ensuring the stability of the optical power output by the LD.

As is apparent from the above description, in the embodiments of the present application, for any one LD in the optical module, two different backlight current reference values may be set in the optical module for the LD. Based on this, first, a first optical module provided in the embodiment of the present application will be described with reference to fig. 3 and 4.

Fig. 3 is a schematic diagram of an overall structure of an optical module provided in an embodiment of the present application and an exploded view of each part of the optical module 300. As shown in fig. 3, the optical module 300 includes a first housing 01, a second housing 02, a handle 03, and a core assembly 04. The core component includes an optical component 041 and a PCB042 (Printed Circuit Board).

It should be noted that the structure of the optical assembly can be referred to the optical assembly shown in fig. 4. In fig. 4, the upper diagram shows a three-dimensional perspective view of the optical module, and the lower diagram shows a cross-sectional view of the optical module. As shown in the lower diagram of fig. 4, a first laser 501, a second laser 502, and a filter 503 may be included in the optical assembly. The first laser 501 includes a first LD and a first PD, and the second laser 502 includes a second LD and a second PD. Optionally, in some possible cases, the first laser may further include a first driver, and the second laser may further include a second driver.

In addition, as shown in fig. 3, the PCB042 may include components such as the MCU0421 thereon. Optionally, in some possible cases, the first driver 0422 and the second driver 0423 may also be located not within the optical assembly, but on the PCB 042.

Fig. 5 is a schematic structural diagram of an optical module provided in an embodiment of the present application. The optical module in fig. 3 and 4 can be realized by the configuration shown in fig. 5. As shown in fig. 5, the optical module may include a first driver 501, a first LD502, a first PD503, a second LD504, a second PD505, an optical filter 506, a second driver 507, and an MCU 508.

The first LD502 and the first PD503 are both connected to the first driver 501, and the second LD504 and the second PD505 are both connected to the second driver 507.

The front light output from the second LD504 is irradiated onto the filter 506. The exit direction of the front light of the filter 506 and the second LD504 may form an angle of 45 degrees. Most of the front light output by the second LD504 is coupled with most of the front light output by the first LD502 through the filter 506 and then enters the optical fiber for transmission. A small portion of the front light output from the second LD504 may be reflected to the first PD 503.

The first driver 501 may include a first MPD (monitor photo detector) pin 1a and a first bias pin 1 b. The first MPD pin 1a is connected to the first PD 503. Through the first MPD pin 1a, the first driver 501 may receive the backlight current fed back by the first PD 503. The first bias pin 1b is connected to an input terminal of the first LD 502. Through the first bias pin 1b, the first driver 501 may output a first bias current required for the operation of the first LD502, so as to drive the first LD to emit light.

The second driver 507 may include a second MPD pin 7a and a second bias pin 7 b. The second MPD pin 7a is connected to the second PD 505. The second driver 507 may receive the backlight current fed back by the second PD505 through the second MPD pin 7 a. The second bias pin 7b is connected to the second LD 504. Through the second bias pin 7b, the second driver 507 may output a second bias current required by the operation of the second LD504, so as to drive the second LD to emit light.

It should be noted that the first driver 501 may further include a first control pin 1c connected to the MCU 508. Through the first control pin 1c, the first driver 501 may receive information output by the MCU 508. The second driver 507 may further include a second control pin 7c connected to the control module. Through the second control pin 7c, the second driver 507 can receive information output by the MCU 508.

The MCU508 may output a control signal for controlling the first LD502 to be turned on or off to the first driver 501 and a control signal for controlling the second LD504 to be turned on or off to the second driver 507. The MCU508 includes a control register, which may store the current status information of the first LD502 and the second LD 504. The MCU508 may acquire current status information of the first LD502 and the second LD504 from the control register and output information to corresponding drivers according to the acquired status information.

1. The optical module is in a debug state.

In this embodiment of the present application, when the optical module is in a debug state, the MCU508 chip may control to turn on the first LD502 in the optical module, and control the second LD504 in the optical module to be in a close state. Thereafter, the MCU508 may read the switching states of the first LD502 and the second LD504 from the control register. At this time, the read status information of the first LD502 is the on status information, and the read status information of the second LD504 is the off status information. The MCU508 may output on-state information of the first LD502 and off-state information of the second LD504 to the first driver 501 and the second driver 507, respectively.

Note that the target power value of the first LD502 may be stored in the first driver 501. The target power value is a power value to which the front light of the first LD502 is to reach. After receiving the off state information of the second LD504 and the on state information of the first LD502, the first driver 501 may output a bias current having a preset value to the first LD 502. The preset value is a current value of a current that enables the first LD502 to operate normally, which is set based on a priori experience. The first LD502 emits front light and backlight by the bias current, and the first PD503 generates a backlight current after detecting the backlight and feeds the backlight current back to the first driver 501. The first driver 501 may determine a power value of front light of the first LD502 according to the detected backlight current value. Thereafter, the first driver 501 may compare the power value of the front light of the first LD502 with the reference power value, and if the power value of the front light is smaller than the reference power value, the first driver 501 may increase the current output to the first LD502 according to the difference between the power value of the front light and the reference power value. The first LD502 emits front light and backlight under the action of the increased current, the first PD503 generates backlight current according to the detected backlight and feeds back the generated backlight current to the first driver 501 again, the first driver 501 continues to refer to the aforementioned method to obtain the current power value of the front light according to the backlight current and compares the current power value of the front light with the reference power value again until the power value of the front light is equal to the reference power value, the current value of the current output to the first LD502 by the first driver 501 at this time is recorded as a first bias current value, the current value of the backlight current received by the first driver 501 at this time is recorded as a second backlight current reference value, and the second backlight current reference value and the state information of the two LDs at this time are correspondingly stored.

After acquiring the first bias current value and the second backlight current reference value, the MCU508 may control the second LD504 to turn on. Thereafter, the MCU508 may read the switching states of the second LD504 and the first LD502 from the control register. At this time, the read state information of the second LD504 is on state information, and the read state information of the first LD502 is also on state information. The MCU508 outputs the on-state information of the second LD504 and the on-state information of the first LD502 to the first driver 501 and the second driver 507, respectively. Meanwhile, the MCU508 may transmit a control signal to the first driver 501 to control the APC closed loop between the first driver 501 and the first LD502, the first PD503 to be in an open loop state. The open-loop state refers to that the first driver 501 does not adjust the output bias current according to the backlight current after receiving the backlight current fed back by the first PD 503.

After the first driver 501 and the first LD502 are in an open loop state, the first driver 501 may output a first bias current having a first bias current value to the first LD502 and output a second bias current to the second LD 504. The current value of the second bias current is equal to the current value when the optical power output by the LD of the second LD504 reaches the preset power value, and the current value of the second bias current may be pre-stored in the MCU 508.

The second LD504 emits front light and backlight under the action of the second bias current, wherein the front light emitted by the second LD504 passes through the optical filter 506, but since the optical filter 506 cannot transmit 100%, part of the light in the front light is reflected to the housing or other parts of the optical module through the optical filter 506, and then is diffused by the housing or other parts and then irradiates the first PD 503. At the same time, the first LD502 will also emit front light and backlight under the action of the first bias current. In this case, the first PD503 detects not only the backlight of the first LD502 but also a part of the light of the second LD 504. The first PD503 converts the detected light into a backlight current and feeds back the backlight current to the first driver 501. As can be seen from this, at this time, the backlight current includes not only the current generated by the backlight of the first LD502 but also the current generated by the interference light of the second LD 504. Since the first driver 501 and the first LD502 are currently in an open loop state, after receiving the backlight current fed back by the first PD503, the first driver 501 does not adjust the bias current output to the first LD502 according to the backlight current. At this time, a current value of the backlight current received by the first driver 501 may be recorded as a first backlight current reference value, and the first backlight current reference value may be stored in correspondence with state information of the two LDs at this time.

Similarly, for the second driver 507, the second LD504, and the second PD505, the method described above may also be referred to obtain a third backlight current reference value corresponding to the second LD504 when the two LDs are simultaneously turned on, and a fourth backlight current reference value corresponding to the second LD504 when only the second LD504 is turned on.

It should be noted that the above-mentioned reference value of the backlight current and the state information of the two corresponding LDs may be stored in the driver, or may be stored in the MCU 508. If the current value is stored in the MCU508, when the backlight current value and the state information of the two corresponding LDs are correspondingly stored, the identifier of the driver corresponding to the corresponding backlight current value may also be correspondingly stored.

Exemplarily, table 1 and table 2 show a mapping relationship table between the backlight current reference value and the state information of the LD stored in the first driver 501 and the second driver 507. Both the first backlight current reference value and the second backlight current reference value are reference values used by the first driver 501 for monitoring the optical power of the front light of the first LD502, and therefore, the first backlight current reference value and the state information of the two corresponding LDs thereof, and the second backlight current reference value and the state information of the two corresponding LDs thereof are stored in the first driver 501, as shown in table 1. Similarly, the third backlight current reference value and the fourth backlight current reference value and their corresponding state information of the LD are stored in the second driver 507, as shown in table 2. Where a1 is a status parameter of the first LD502, and when the status parameter is 1, it indicates that the first LD502 is in an on state, and when the status parameter is 0, it indicates that the first LD502 is in an off state. A2 is a status parameter of the second LD504, and indicates that the second LD504 is in an on state when the status parameter is 1, and indicates that the second LD504 is in an off state when the status parameter is 0.

TABLE 1 status information in the first driver 501 relates to backlight currentMapping relationships between reference values

Status information	Reference value of backlight current
		A1=1，A2=1	First backlight current reference value
A1=1，A2=0	Second backlight current reference value

Table 2, mapping relationship between state information and backlight current reference value in the second driver 507

Status information	Reference value of backlight current
		A1=1，A2=1	Third backlight current reference value
A1=0，A2=1	Fourth backlight current reference value

Alternatively, table 3 shows a mapping table in the MCU508 when the backlight current reference value is stored in the MCU 508. When the backlight current reference value is stored in the MCU508, in order to distinguish which driver the respective backlight current reference value corresponds to, when the backlight current reference value and the state information of the corresponding two LDs are stored, the driver identification corresponding to the backlight current reference value may also be correspondingly stored. As shown in table 3, the ID1 is used to uniquely identify the first drive 501 and the ID2 is used to uniquely identify the second drive 507. When two LDs are turned on simultaneously, the driver ID corresponding to the first backlight current reference value is ID1, which indicates that the first backlight current reference value is the reference value corresponding to the first driver 501. The driver ID2 corresponds to the third backlight current reference value, which indicates that the third backlight current reference value is the reference value corresponding to the second driver 507. Similarly, the second backlight current reference value is a reference value corresponding to the first driver 501, and the fourth backlight current reference value is a reference value corresponding to the second driver 507.

TABLE 3 mapping relationship between State information and backlight Current reference values in MCU

Driver identification	Status information	Reference value of backlight current
			ID1	A1=1，A2=1	First backlight current reference value
ID1	A1=1，A2=0	Second backlight current reference value
			ID2	A1=1，A2=1	Third backlight current reference value
ID2	A1=0，A2=1	Fourth backlight current reference value

2. Optical module is in operating condition

In this embodiment of the application, when the optical module receives the turn-on instructions for the two LDs, the MCU508 chip of the optical module may output a first control signal to the first driver 501 and the second driver 507 to control the first LD502 and the second LD504 to be turned on simultaneously. The first control signal can control the corresponding device to be turned on. Illustratively, the first control signal may be an enable signal.

After the first LD502 and the second LD504 are simultaneously turned on, the state information of the corresponding first LD502 and second LD504 in the control register is set as the on state information. The MCU508 may search for and detect whether the status information of the first LD502 and the second LD504 changes from the control register in real time. When the MCU508 detects that the status information of the first LD502 and the second LD504 changes, the changed status information may be obtained, and the status of the current two LDs may be determined according to the changed status information.

When it is determined that both LDs are in the on state, if the backlight current reference value is stored in the MCU508, the MCU508 may obtain the first backlight current reference value and the third backlight current reference value corresponding to the state information of both LDs from the aforementioned mapping relationship table, and then the MCU508 may send the first backlight current reference value to the first driver 501 according to the driver identifier corresponding to the first backlight current reference value. And sending the third backlight current reference value to the second driver 507 according to the driver identifier corresponding to the third backlight current reference value. After receiving the first backlight current reference value, the first driver 501 may compare the received current value of the first backlight current fed back by the first PD503 with the first backlight current reference value, so as to monitor the optical power of the front light of the first LD502, and further drive the first LD to emit light. After receiving the third backlight current reference value, the second driver 507 may compare the received current value of the second backlight current fed back by the second PD505 with the third backlight current reference value, so as to monitor the optical power of the front light of the second LD504, and further drive the second LD to emit light.

Alternatively, if the backlight current reference value is stored in a corresponding driver, the MCU508 may output the acquired on-state information of the first LD502 and the second LD504 to the first driver 501 and the second driver 507, respectively. The first driver 501 may obtain the corresponding first backlight current reference value according to the received state information after receiving the state information of the two LDs. Thereafter, the first driver 501 may compare the received current value of the first backlight current fed back by the first PD503 with the first backlight current reference value, so as to monitor the optical power of the front light of the first LD 502. Similarly, the second driver 507 may also obtain a third backlight current reference value with reference to the foregoing implementation manner, and monitor the backlight current fed back by the second PD505 with the third backlight current reference value as a standard value, thereby implementing monitoring of the optical power of the front light of the second LD504

Since the first backlight current reference value is the current value of the backlight current output under the interference of the light of the second LD504 when the light power of the front light output by the first LD502 reaches the reference power value when the first PD503 is in the open loop state, the light power of the front light of the first LD502 is monitored by using the first backlight current reference value as a standard value in the state that the two LDs are simultaneously turned on, the problem of the interference of the light of the second LD504 on the light power of the first LD502 can be effectively solved, and the stability of the output power of the first LD502 is ensured. Similarly, the third backlight current reference value is used as a standard value to monitor the optical power of the front light of the second LD504, so as to ensure the stability of the output power of the second LD 504.

When the optical module receives an on instruction for the first LD502 and an off instruction for the second LD504, the MCU508 of the optical module may output a first control signal to the first driver 501 and a second control signal to the second driver 507, so as to control the first LD502 to be turned on and the second LD504 to be turned off. Wherein the second control signal is used to control the corresponding device to be turned off. After the first LD502 is turned on and the second LD504 is turned off, the state information of the first LD502 is set as on state information in the control register, and the state information of the second LD504 is set as off state information. At this time, the MCU508 may search and detect whether the state information of the first LD502 and the second LD504 changes from the control register, and when it is detected that the state information of the first LD502 and the second LD504 changes, determine the current state of the first LD502 and the second LD504 according to the changed state information.

After determining that the first LD502 is in the on state and the second LD504 is in the off state, if the backlight current reference value is stored in the MCU508, the MCU508 may obtain a corresponding second backlight current reference value from the mapping table according to the obtained state information, and output the second backlight current reference value to the first driver 501 according to the driver identifier corresponding to the second backlight current reference value. The first driver 501 may compare the received current value of the first backlight current fed back by the first PD503 with the second backlight current reference value after receiving the second backlight current reference value, so as to monitor the optical power of the front light of the first LD 502.

Similarly, when the optical module receives a turn-off command for the first LD502 and a turn-on command for the second LD504, the MCU508 may output a fourth backlight current reference value to the second driver 507, and the second driver 507 may monitor the optical power of the front light of the second LD504 with the fourth backlight current reference value as a standard value. The implementation of this process may refer to the foregoing related implementation manner, and this embodiment is not described again.

It can be seen that, in the embodiment of the present application, the first backlight current reference value and the second backlight current reference value are different. The second backlight current reference value is a current value of the backlight current fed back by the first PD503 when the light power of the front light reaches the reference power value at a certain temperature by the first LD502 in a state where only the first LD502 is turned on. The first backlight current reference value is a current value of the backlight current output by the first PD503 when the first PD503 is in an open loop state and the optical power of the front light of the first LD502 reaches a reference power value at a certain temperature in a state where both LDs are turned on. Therefore, when only the first LD502 is turned on, the second backlight current reference value is used as a standard value to monitor the optical power of the front light of the first LD502, and further the first LD502 is driven to emit light; when the first LD502 and the second LD504 are simultaneously turned on, the first backlight current reference value is used as a standard value to monitor the light power of the front light of the first LD502, and then the first LD502 is driven to emit light, so that the problem of misjudgment caused when the light power of the first LD502 is monitored by adopting the same standard value in all states in the related art can be effectively avoided, the problem of interference of the light of the second LD504 on the light power of the first LD502 when the two LDs are simultaneously turned on is solved, and the stability of the output power of the first LD502 is ensured. Similarly, the third backlight current reference value is used as a standard value to monitor the optical power of the front light of the second LD504, and the problem of interference of the light of the first LD502 to the optical power of the second LD504 when the two LDs are simultaneously turned on can also be solved, so that the stability of the output power of the second LD504 is ensured. Therefore, the optical module provided by the embodiment of the application can ensure that the two LDs do not interfere with each other, and ensure the stability of the optical power of the two LDs.

It should be noted that, in some possible cases, the first LD in the optical module may be normally open, that is, the first LD may not be closed. In this case, the backlight current reference value may be previously configured for the second LD directly according to a case where two LDs are simultaneously turned on. For the first LD, two different backlight current reference values may be configured for the first LD with reference to the related processing manner described in the foregoing embodiment, and the optical power of the front light of the first LD is monitored according to the two different backlight current reference values.

In the above embodiment, the case where the optical module includes two drivers, and the two drivers drive one set of LD and PD, respectively, is mainly described. In some possible embodiments, two sets of LD and PD may also be driven simultaneously by one driver. Next, a specific implementation process of the optical module in the embodiment of the present application in the debugging state and the operating state when two sets of LD and PD are driven by one driver will be described with reference to fig. 6.

Fig. 6 is a schematic structural diagram of another optical module provided in the embodiment of the present application. As shown in fig. 6, the optical module may include a driver 601, a first LD602, a first PD603, a second LD604, a second PD605, a filter 606, and an MCU 607.

The first LD602, the first PD603, the second LD604, and the second PD605 are all connected to the driver 601.

The front light output from the second LD604 is directed to the filter 606. The exit directions of the front lights of the filter 606 and the second LD604 may form an angle of 45 degrees. Most of the front light output by the second LD604 is coupled with most of the front light output by the first LD602 after passing through the filter 606, and then enters the optical fiber for transmission. A small portion of the front light output from the second LD604 may be reflected to the first PD 603. Similarly, after the front light output by the first LD602 is irradiated to the filter 606, most of the light passes through the filter 606, and a very small portion of the light may be reflected to the second PD 605.

The driver 601 may include a first MPD (monitor photo detector) pin 6a and a first bias pin 6 c. The first MPD pin 6a is connected to the first PD 603. The driver 601 may receive the backlight current fed back by the first PD603 through the first MPD pin 6 a. The first offset pin 6c is connected to an input terminal of the first LD 602. Through the first bias pin 6c, the first driver 601 may output a first bias current required for the operation of the first LD602, thereby driving the first LD602 to emit light. In addition, the driver 601 further includes a second MPD pin 6b and a second bias pin 6 d. The second MPD pin 6b is connected to the second PD605, and the backlight current fed back by the second PD605 can be received through the second MPD pin 6 b. The second bias pin 6d is connected to an input terminal of the second LD604, and a second bias current required for the operation of the second LD604 can be output through the second bias pin 6d, so that the second LD604 is driven to emit light.

It should be noted that the driver 601 may further include a control pin 6e connected to the MCU 607. The driver 601 can receive information output by the MCU607 through the control pin 6 e.

The MCU607 may output a control signal for controlling the first LD602 to be turned on or off, and a control signal for controlling the second LD604 to be turned on or off. MCU607 includes a control register, which may store the current status information of first LD602 and second LD 604. MCU607 may acquire current status information of first LD602 and second LD604 from the control register and output information to driver 601 according to the acquired status information.

1. The optical module is in a debug state.

In this embodiment of the application, when the optical module is in a debug state, a first bias current value and a second backlight current reference value when the output power of front light of the first LD602 reaches a reference power value when the first LD602 is in an on state and the second LD604 is in an off state may be obtained first, and the identifier of the first LD602, the second backlight current reference value, and the state information of the first LD602 and the second LD604 are stored correspondingly. Then, a second bias current value and a fourth backlight current reference value when the output power of front light of second LD604 reaches a reference power value when second LD604 is in an on state and first LD602 is in an off state may be obtained, and the identifier of second LD604, the fourth backlight current reference value, and the state information of first LD602 and second LD604 may be stored correspondingly. Then, according to the first bias current value and the second bias current value, when the first LD602 and the second LD604 are simultaneously turned on and the first LD602, the first PD603 and the driver 601 are in an open loop state, the current value of the backlight current of the first PD603, that is, the first backlight current reference value, is obtained, and the identifier of the first LD602, the first backlight current reference value and the state information of the first LD602 and the second LD604 are correspondingly stored. When the first LD602 and the second LD604 are simultaneously turned on and the second LD604, the second PD605 and the driver 601 are in an open loop state, a current value of the backlight current of the second PD605, that is, a third backlight current reference value is obtained, and the identifier of the second LD604, the third backlight current reference value and the current state information of the first LD602 and the second LD604 are stored correspondingly.

Through the above steps, the driver 601 or the MCU607 can store the corresponding relationship as shown in table 4. Where a1 is a status parameter of the first LD602, and when the status parameter is 1, it indicates that the first LD602 is in an on state, and when the status parameter is 0, it indicates that the first LD602 is in an off state. A2 is a status parameter of second LD604, and indicates that second LD604 is in an on state when the status parameter is 1, and indicates that second LD604 is in an off state when the status parameter is 0.

TABLE 4 mapping between state information and backlight current reference values in driver 601

LD identification	Status information	Reference value of backlight current
			01	A1=1，A2=1	First backlight current reference value
01	A1=1，A2=0	Second backlight current reference value
			02	A1=1，A2=1	Third backlight current reference value
02	A1=0，A2=1	Fourth backlight current reference value

In addition, it should be noted that, for a specific implementation method for obtaining each backlight current reference value in the above table, reference may be made to related implementation manners in the foregoing embodiments, and details of the embodiments of the present application are not described herein again.

2. Optical module is in operating condition

In the embodiment of the present application, MCU607 in the optical module may control first LD602 and second LD604 by referring to the related methods described in the foregoing embodiments, and detect whether status information of first LD602 and second LD604 changes.

If the correspondence in table 2 is stored in MCU607, MCU607 may determine the current states of first LD602 and second LD604 according to the changed state information when it detects that the state information of first LD602 and second LD604 changes.

If both the first LD602 and the second LD604 are currently in the on state, the MCU607 may obtain the first backlight current reference value and the corresponding LD identifier from the above correspondence to obtain a first information set, obtain the third backlight current reference value and the corresponding LD identifier to obtain a second information set, and send the obtained two information sets to the driver 601. In this way, after the driver 601 receives the current value of the first backlight current fed back by the first PD603, the identifier of the LD corresponding to the identifier of the first PD603, that is, the identifier of the first LD602, may be determined according to the identifier of the first PD603, and then, the driver 601 may obtain a first backlight current reference value from the first information set according to the identifier of the first LD602, and compare the current value of the first backlight current fed back by the first PD603 with the first backlight current reference value, so as to implement monitoring of the optical power of the front light of the first LD602, and further drive the first LD602 to emit light.

Similarly, after the driver 601 receives the current value of the second backlight current fed back by the second PD605, the identifier of the LD corresponding to the second PD605, that is, the identifier of the second LD604, may be determined according to the identifier of the second PD 605. Then, a third backlight current reference value is obtained from the second information set according to the identifier of the second LD 604. The current value of the second backlight current fed back by the second PD605 is compared with the third backlight current reference value, so as to monitor the optical power of the front light of the second LD604, and further drive the second LD604 to emit light.

Of course, if the first LD602 is currently in the on state and the second LD604 is currently in the off state, the MCU607 may acquire and transmit the second backlight current reference value to the driver 601. The driver 601 may compare the second backlight current reference value as a standard value with the current value of the first backlight current fed back by the first PD603, so as to monitor the optical power of the front light of the first LD602, and further drive the first LD602 to emit light.

If the second LD604 is currently in the on state and the first LD602 is currently in the off state, the MCU607 may acquire a fourth backlight current reference value and transmit the fourth backlight current reference value to the driver 601. The driver 601 may compare the fourth backlight current reference value as a standard value with the current value of the second backlight current fed back by the second PD605, so as to monitor the optical power of the front light of the second LD604, and further drive the second LD604 to emit light.

Alternatively, if the correspondence shown in table 2 above is stored in the driver 601, the MCU607 may send the changed state information to the driver 601 after detecting that the state information of the first LD602 and the second LD604 changes, and the driver 601 may obtain the backlight current reference value of each LD from the correspondence according to the received state information, and compare the current value of the backlight current fed back by the PD corresponding to each LD with the backlight current reference value corresponding to the LD, so as to monitor the light power of the front light of each LD.

In the embodiment of the present application, the first backlight current reference value and the second backlight current reference value are different. The second backlight current reference value is a current value of the backlight current fed back by the first PD603 when the light power of the front light reaches the reference power value at a certain temperature by the first LD602 in a state where only the first LD602 is turned on. The first backlight current reference value is a current value of the backlight current output by the first PD603 when the first PD603 is in an open loop state and the optical power of the front light of the first LD602 reaches a reference power value at a certain temperature in a state where both LDs are turned on. Therefore, when only the first LD602 is turned on, the second backlight current reference value is used as a standard value to monitor the optical power of the front light of the first LD602, and then the first LD602 is driven to emit light, and when the first LD602 and the second LD604 are turned on simultaneously, the first backlight current reference value is used as a standard value to monitor the optical power of the front light of the first LD602, and then the first LD602 is driven to emit light, so that the problem of misjudgment caused when the optical power of the first LD602 is monitored by using the same standard value in all states in the related art can be effectively avoided, the problem of interference of the light of the second LD604 on the optical power of the first LD602 when the two LDs are turned on simultaneously is solved, and the stability of the output power of the first LD602 is ensured. Similarly, the third backlight current reference value and the fourth backlight current reference value are used as the standard values of the second LD604 in two different scenes to monitor the light power of the front light of the second LD604, so as to ensure the stability of the output power of the second LD 604. Therefore, in the optical module provided by the embodiment of the application, when the two LDs are simultaneously turned on, the two LDs can mutually resist the interference of the light of the other LD, so that the stability of the optical power of the output front light is ensured.

It should be noted that, with respect to the optical module described in the foregoing embodiment, when two LDs are simultaneously in an on state, the optical module monitors the optical power of the front light of the first LD602 through the first backlight current reference value, and then drives the first LD602 to emit light. In this way, when the light power of the front light of the first LD602 is stabilized, the current value of the backlight current fed back by the first PD603 will be equal to the first backlight current reference value. That is, as shown in fig. 6, a connection line L from the first PD603 to the first MPD pin 6a₁The current value of the current is the first backlight currentA reference value. However, when the first LD602 is turned on but the second LD604 is turned off, the optical module monitors the optical power of the front light of the first LD602 by the second backlight current reference value, and then drives the first LD602 to emit light. Thus, when the light power of the front light of the first LD602 reaches a stable value, the current value of the backlight current fed back by the first PD603 will be equal to the second backlight current reference value. That is, the connection line L from the first PD603 to the first MPD pin 6a₁The current value of the current in (1) is a second backlight current reference value. As can be seen, in the case where the first LD602 and the second LD604 are simultaneously turned on and in the case where only the first LD602 is turned on, when the optical power of the front light of the first LD602 reaches stability, the connection line L₁The current values of the currents in (1) are different. In other words, the current value of the backlight current fed back by the first PD603 when the light power of the front light of the first LD602 is stabilized when the first LD602 and the second LD604 are simultaneously turned on is not equal to the current value of the backlight current fed back by the first PD603 when the light power of the front light of the first LD602 is stabilized when only the first LD602 is turned on.

Similarly, the current value of the backlight current fed back by the second PD605 when the light power of the front light of the second LD604 is stabilized when the first LD602 and the second LD604 are turned on simultaneously is different from the current value of the backlight current fed back by the second PD605 when the light power of the front light of the second LD604 is stabilized when only the second LD604 is turned on.

It will be understood by those skilled in the art that all or part of the steps for implementing the above embodiments may be implemented by hardware, or may be implemented by a program instructing relevant hardware, where the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disk, etc.

The above description is only exemplary of the present application and should not be taken as limiting, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. An optical module is characterized by comprising a first Laser Diode (LD), a second LD, a first backlight detector (PD), a second PD and a first driver, wherein the first LD and the first PD are respectively connected with the first driver, and the first driver drives the first LD to emit light according to a feedback value of the first PD;

2. The light module of claim 1,

the second LD and the second PD are respectively connected with the first driver, and the first driver drives the second LD to emit light according to the feedback value of the second PD;

when the first LD and the second LD are simultaneously in an on state and the optical powers of the first LD and the second LD are both stable, the current value fed back by the second PD and received by the first driver is a third current value;

when the second LD is in an on state, the first LD is in an off state, and the optical power of the second LD is stable, the current value fed back by the second PD and received by the first driver is a fourth current value, and the fourth current value is different from the third current value.

3. The light module of claim 2, wherein the first driver includes a first bias pin and a second bias pin;

the first bias pin is used for outputting bias current for driving the first LD to emit light to the first LD;

the second bias pin is used for outputting bias current for driving the second LD to emit light to the second LD.

4. The light module of claim 2, wherein the first driver comprises a first Monitor Photodetector (MPD) pin and a second MPD pin, the first MPD pin to receive a first backlight current fed back by the first PD, the second MPD pin to receive a second backlight current fed back by the second PD.

5. The optical module according to claim 1, wherein the optical module further comprises a second driver, the second LD and the second PD are respectively connected to the second driver, and the second driver drives the second LD to emit light according to a feedback value of the second PD;

when the first LD and the second LD are simultaneously in an on state and the optical powers of the first LD and the second LD are both stable, the current value fed back by the second PD and received by the second driver is a third current value;

when the second LD is in an on state, the first LD is in an off state, and the optical power of the second LD is stable, the current value fed back by the second PD and received by the second driver is a fourth current value, and the fourth current value is different from the third current value.