CN214540012U - Coupling structure of M-Z modulator and light source and laser radar comprising coupling structure - Google Patents

Abstract

The utility model provides a coupling structure of M-Z modulator and light source reaches laser radar including it, coupling structure wherein includes slope piece, light source, lens and M-Z modulator, wherein: the surface of the inclined block has an inclination angle; the light source is arranged on the surface of the inclined block; and the lens focuses the light beam emitted by the light source and transmits the focused light beam to the receiving end surface of the M-Z modulator. According to the scheme, the light source is arranged on the inclined block with the inclined angle, so that the polarization angle of the light beam of the light source has a deflection condition before entering the M-Z modulator, the light beam can be directly coupled to the M-Z modulator after passing through the lens, a wave plate is omitted, a torsion optical fiber is not required to be arranged on the input end face of the modulator, and the coupling efficiency can be ensured while the coupling structure is simplified.

Description

Coupling structure of M-Z modulator and light source and laser radar comprising coupling structure

Technical Field

The utility model relates to an optical fiber communication technical field, concretely relates to coupling structure of M-Z modulator and light source reaches laser radar including it.

Background

The M-Z modulator (mach-zehnder modulator) is widely used in optical fiber communication due to its advantages in terms of broadband, low half-wave voltage, and low chirp characteristics, but requires a high-power optical signal for transmission, so the coupling technology of the M-Z modulator and the light source is very important.

In the prior art, the coupling of the M-Z modulator to the light source is achieved by two ways:

in the indirect coupling mode, light beams emitted by the light source pass through a lens and are focused to an optical fiber twisted by 45 degrees, and the light beams emitted by the light source are coupled into the M-Z modulator through the optical fiber.

In the direct coupling mode, light beams emitted by the light source pass through a lens and an 1/2 wave plate and are coupled into the M-Z modulator after being focused.

The two coupling modes are convenient and fast in indirect coupling mode, but the coupling efficiency is low; the direct coupling mode has complex structure and high process requirement, but has high coupling efficiency and high cost. Therefore, the existing coupling modes of the M-Z modulator and the light source have the problem that convenience and coupling efficiency cannot be simultaneously considered.

SUMMERY OF THE UTILITY MODEL

In view of this, the present invention provides a coupling structure of an M-Z modulator and a light source and a laser radar including the same, which can simplify the coupling structure and ensure the coupling efficiency.

The utility model provides a coupling structure of M-Z modulator and light source, including slope piece, light source, lens and M-Z modulator, wherein:

the surface of the inclined block has an inclination angle; the light source is arranged on the surface of the inclined block; and the lens focuses the light beam emitted by the light source and transmits the focused light beam to the receiving end surface of the M-Z modulator.

Optionally, the above coupling structure of the M-Z modulator and the light source further includes:

an isolator disposed between the lens and a receiving end face of the M-Z modulator;

and the light beam focused by the lens is coupled into the receiving end surface of the M-Z modulator after passing through the isolator.

Optionally, in the above coupling structure of the M-Z modulator and the light source, the tilting block includes:

a base plate;

the inclined seat is fixedly arranged on the base plate; the inclined surface of the inclined seat is used as the surface of the inclined block.

Optionally, in the above-mentioned coupling structure of the M-Z modulator and the light source, the tilting base is disposed in a central region of the base plate.

Optionally, in the above coupling structure of the M-Z modulator and the light source, the coupling structure further includes a balancing base:

the balance seat and the inclined seat are symmetrically arranged on two sides of the base plate.

Optionally, in the above coupling structure of the M-Z modulator and the light source, the light source is a distributed feedback laser; the lens is a condensing lens.

Optionally, in the above-mentioned coupling structure of the M-Z modulator and the light source, the tilt angle is 45 degrees.

Based on the same inventive concept, the utility model also provides a laser radar, including any one above M-Z modulator and the coupling structure of light source, still include:

the driving current output end of the circuit control module is connected with the light source, the bias voltage output end of the circuit control module is connected with the bias voltage input end of the M-Z modulator, and the high-frequency signal output end of the circuit control module is connected with the high-frequency signal input end of the M-Z modulator;

a detector receiving the reflected light signal and converting the reflected light signal into an electrical signal; the detector transmits the electric signal to a monitoring current input end of the circuit control module; the reflected light signal is obtained by reflecting the light signal emitted by the high-frequency signal of the M-Z modulator through an obstacle.

Optionally, in the laser radar, an output end of the M-Z modulator is connected to a polarization maintaining fiber.

Optionally, in the laser radar, the M-Z modulator is a lithium niobate intensity modulator.

The utility model provides an above technical scheme compares with prior art, has following beneficial effect at least: the light source is arranged on the inclined block with the inclined angle, so that the polarization angle of the light beam of the light source has a deflection condition before entering the M-Z modulator, the light beam can be directly coupled to the M-Z modulator after passing through the lens, a wave plate is omitted, and a torsion optical fiber is not required to be arranged on the input end face of the modulator, so that the coupling structure can be simplified and the coupling efficiency can be ensured.

Drawings

Fig. 1 is a schematic structural diagram illustrating a coupling structure between an M-Z modulator and a light source according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of an inclined block according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a laser radar according to an embodiment of the present invention;

fig. 4a and 4b are circuit diagrams of internal functional modules of the circuit control module according to an embodiment of the present invention.

Detailed Description

The embodiments of the present invention will be further explained with reference to the drawings. In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description of the present invention, and do not indicate or imply that the device or component to which the reference is made must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Wherein the terms "first position" and "second position" are two different positions.

The present embodiment provides a coupling structure of an M-Z modulator and a light source, as shown in fig. 1 and 2, comprising a tilting block 200, a light source 101, a focus isolation assembly 102, and an M-Z modulator 103. Wherein the focus isolation assembly 102 comprises a lens. The surface of the inclined block 200 has an inclination angle; the light source 101 is arranged on the surface of the inclined block; the lens focuses the light beam emitted from the light source 101 and transmits the focused light beam to the receiving end surface of the M-Z modulator 103.

Taking the polarization direction of the M-Z modulator 103 as the horizontal direction as an example, after the light source 101 is fixed on the inclined block by selecting the inclined blocks with different inclination angles, the light beam of the light source 101 has a certain deflection angle, so that the light beam of the light source 101 can be directly coupled into the M-Z modulator 103 after being focused by the lens. Compared with the prior art, the scheme adopts a direct coupling mode, omits 1/2 wave plates, reduces the structural complexity, and has the advantages of convenient coupling operation and high coupling efficiency. Moreover, aiming at modulators with different polarization states, the light source can be placed at a certain angle, and high-efficiency coupling with X-cut, Y-cut and Z-cut M-Z intensity modulators can be realized.

In some embodiments, the above-mentioned coupling structure of the M-Z modulator and the light source, the focusing isolation assembly 102 may further include an isolator disposed between the lens and the receiving end surface of the M-Z modulator 103; and the light beam focused by the lens is coupled into the receiving end surface of the M-Z modulator after passing through the isolator. In the scheme, the lens and the isolator are integrated together to be used as the focusing isolation assembly 102, so that the space utilization rate is improved.

In this embodiment, the inclination angle is preferably 45 °. The light source 101 is a 1550nm DFB laser, the lens is a 1550nm condensing lens, divergent light of the light source is converged to one point, and the isolator is a 1550nm isolator, so that unstable output power of the light source caused by echo reflection oscillation is prevented; the M-Z modulator is an X-cut M-Z intensity modulator and a lithium niobate intensity modulator, the polarization direction is horizontal, and the output light power is changed by changing the modulation voltage, so that the modulation effect is achieved.

In addition, in the above solution, the inclined block 200 may be directly implemented by a triangle having a certain inclination angle. Alternatively, as shown in fig. 2, the tilting block 200 includes a base plate 201; an inclined base 202 fixedly provided on the base plate 201; the inclined surface of the inclined seat 202 serves as a surface of the inclined block 200. The base plate 201 has a larger area, and the stability of the installation of the light source 101 can be ensured by the arrangement mode of the base plate 201.

In an implementation, the tilting base 202 is a triangular block, and the tilting base 202 is disposed in a central region of the base plate 201. As another realizable way, the tilting block further comprises a balance seat 204, and the balance seat 204 and the tilting seat 202 are symmetrically arranged on two sides of the base plate 201. From the configuration shown in FIG. 2, in which the tilting seat 202 can be enlarged in the connection surface with the base plate 201 by the coaming 203, the balancing seat 204 can be directly made of a rectangular parallelepiped plate material. When the light source 101 is arranged on the tilting seat 202, the stability of the whole structure is not affected due to the balance effect of the coaming 203 and the balance seat 204.

The present invention further provides a lidar in some embodiments, as shown in fig. 3, including the coupling structure of the M-Z modulator and the light source described in any of the above embodiments, a circuit control module 104, a driving current output terminal 301 of the circuit control module 104 connected to the light source 101, a bias voltage output terminal 302 of the circuit control module 104 connected to a bias voltage input terminal of the M-Z modulator 103, and a high-frequency signal output terminal 303 of the circuit control module 104 connected to a high-frequency signal input terminal of the M-Z modulator 103; a detector 105 receiving the reflected light signal and converting the reflected light signal into an electrical signal; the detector 105 transmits the electrical signal to a monitor current input 304 of the circuit control module 104; the reflected light signal is obtained by reflecting the light signal emitted by the high-frequency signal of the M-Z modulator 103 through the obstacle 106.

The circuit control module may refer to a circuit design scheme in the existing laser radar, and as shown in fig. 4a and 4b, the circuit control module is an implementation manner of a driving current generating circuit, a temperature control circuit, and an operational amplifier circuit adopted in this embodiment, wherein a node Q0 is connected with a node Q1, and a specific working principle may refer to the existing scheme, which is not described in detail in this embodiment.

As another application, the laser radar may also be applied to electronic countermeasure, in which case the signal output by the M-Z modulator 103 may be sent to the photoelectric conversion module 107 for electronic countermeasure to obtain a high-frequency signal.

In the above scheme, the output end of the M-Z modulator 103 is connected to a polarization maintaining fiber, and the polarization maintaining fiber can maintain the polarization state of light transmission in the whole optical path. The M-Z modulator is a lithium niobate intensity modulator, and the lithium niobate intensity modulator is widely applied, so that the scheme of the application has wide application scenes. The scheme of the application provides a 45-degree coupling technology of an X-cut M-Z intensity modulator with an innovative structure, and the technology has the advantages of simple structure, convenience and quickness in coupling mode, high coupling efficiency, low cost and the like, improves the production efficiency and the qualification rate of products, and reduces the production cost. Moreover, because space is saved, an M-Z intensity modulator with a longer length can be used, and the communication bandwidth is improved.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.

Claims (10)

1. A coupling structure of an M-Z modulator and a light source, comprising a tilting block, a light source, a lens and an M-Z modulator, wherein:

the surface of the inclined block has an inclination angle; the light source is arranged on the surface of the inclined block; and the lens focuses the light beam emitted by the light source and transmits the focused light beam to the receiving end surface of the M-Z modulator.

2. The M-Z modulator and light source coupling structure of claim 1, further comprising:

an isolator disposed between the lens and a receiving end face of the M-Z modulator;

and the light beam focused by the lens is coupled into the receiving end surface of the M-Z modulator after passing through the isolator.

3. The M-Z modulator and light source coupling structure of claim 2, wherein the tilt block comprises:

a base plate;

the inclined seat is fixedly arranged on the base plate; the inclined surface of the inclined seat is used as the surface of the inclined block.

4. The M-Z modulator and light source coupling structure of claim 3, wherein:

the tilting base is disposed in a central region of the base plate.

5. The M-Z modulator and light source coupling structure of claim 3, further comprising a balancing stand:

the balance seat and the inclined seat are symmetrically arranged on two sides of the base plate.

6. The M-Z modulator and light source coupling structure of any one of claims 2-5, wherein:

the light source is a distributed feedback laser; the lens is a condensing lens.

7. The M-Z modulator and light source coupling structure of claim 6, wherein:

the inclination angle is 45 degrees.

8. A lidar comprising the M-Z modulator of any one of claims 1-7 coupled to a light source, further comprising:

the driving current output end of the circuit control module is connected with the light source, the bias voltage output end of the circuit control module is connected with the bias voltage input end of the M-Z modulator, and the high-frequency signal output end of the circuit control module is connected with the high-frequency signal input end of the M-Z modulator;

a detector receiving the reflected light signal and converting the reflected light signal into an electrical signal; the detector transmits the electric signal to a monitoring current input end of the circuit control module; the reflected light signal is obtained by reflecting the light signal emitted by the high-frequency signal of the M-Z modulator through an obstacle.

9. The lidar of claim 8, wherein:

and the output end of the M-Z modulator is connected with a polarization maintaining optical fiber.

10. The lidar of claim 9, wherein:

the M-Z modulator is a lithium niobate intensity modulator.

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