A device and method for adjusting the position of a mirror in a tunable laser cavity

Abstract

The application belongs to the technical field of lasers, and particularly relates to a position adjusting device and method of a resonant cavity mirror of a tunable laser source, which comprises a mirror supporting mechanism and an actuating mechanism located below the mirror supporting mechanism; the mirror supporting mechanism comprises a mirror supporting arm, a cantilever and a mirror supporting plate; the lower end of the mirror supporting arm is connected to one end of the cantilever, the other end of the cantilever is rotationally connected to the actuating mechanism; the upper end of the mirror supporting arm is connected to the mirror supporting plate, and a mirror supporting point is arranged on one side of the mirror supporting plate. The position adjusting device of the resonant cavity mirror of the tunable laser source is designed in a separated mode, the machining difficulty can be reduced, the mirror clamping angle is variable, the resonant state of the resonant mirror can be adjusted, and the problem that the fixed resonant characteristics output realized by the assembly mode of the conventional integrated laser tuning source rotating body and the external cavity laser tuning source cavity body cannot meet the needs of users for various specifications of LM-TLS is solved.

Description

Technical Field

[0001] This invention belongs to the field of laser technology, and particularly relates to a position adjustment device and method for a tunable laser source resonant cavity reflector. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] External cavity tunable laser sources (also known as Littleman-Metcalf type tunable laser sources, abbreviated as LM-TLS) have been widely used in high-speed coherent optical communication networks based on high-order optical modulation formats, fiber optic three-dimensional shape frequency domain sensing, linear frequency sweep trace gas detection, and autonomous driving due to their outstanding advantages such as single longitudinal mode, narrow linewidth, continuously tunable output wavelength, and low phase noise. They are an indispensable ideal test source in the process of dynamic reconstruction of high-speed coherent optical communication networks and micron-level communication link diagnosis.

[0004] Currently, a fixed-angle integrated laser tuning source rotor and an external cavity laser tuning source cavity are often assembled within the same optical unit module to achieve lasing output with fixed resonance characteristics. However, assembling the fixed-angle integrated laser tuning source rotor and the external cavity laser tuning source cavity within the same optical unit module is inconvenient for extending or compressing the external cavity length, hinders the adjustment of the resonant state of the resonant mirror, complicates manufacturing cost control, and makes individual replacement of the resonant mirror difficult. The use of a fixed-angle integrated laser tuning source rotor significantly impacts the external cavity laser tuning source's optimizability for various output spectral linewidths and output power, its ability to quickly lock onto resonant modes, and its ability to replace and upgrade resonant mirrors with physical length compensation capabilities for specific applications.

[0005] Therefore, laser output with fixed resonance characteristics is difficult to meet the actual needs of different users. Users sometimes need LM-TLS with multiple specifications (linewidth, power and tuning range, etc.) according to different actual application requirements, which means that multiple complete units must be purchased, resulting in complicated test systems and increased operation and maintenance costs. Summary of the Invention

[0006] To overcome the shortcomings of the prior art, the present invention provides a position adjustment device and method for a tunable laser source resonant cavity mirror.

[0007] To achieve the above objectives, one or more embodiments of the present invention provide the following technical solutions:

[0008] The first aspect of the present invention provides a position adjustment device for a tunable laser source resonant cavity mirror, comprising: a mirror support mechanism and an actuation mechanism located below the mirror support mechanism;

[0009] The mirror support mechanism includes: a mirror support arm, a first rotating arm, and a mirror support plate;

[0010] The lower end of the reflector support arm is connected to one end of the first rotating arm, and the other end of the first rotating arm is rotatably connected to the actuation mechanism via a rotating shaft; the upper end of the reflector support arm is connected to the reflector support plate, and a reflector support block is provided on one side of the reflector support plate.

[0011] Furthermore, the number of the reflector support blocks is three.

[0012] Furthermore, the first and second mirror support blocks are coaxially arranged at the upper edge of the side of the mirror support plate, and the third mirror support block is arranged at the lower edge of the side of the mirror support plate.

[0013] Furthermore, the first and second mirror support blocks are spaced a certain distance apart, and the third mirror support block is located at the midpoint of the lower edge of the side of the mirror support plate.

[0014] Furthermore, bolt holes are provided on the side of the reflector support arm, and bolts for fixing the first rotating arm are provided in the bolt holes; the pitch angle of the reflector is adjusted by the bolts between the reflector support arm and the first rotating arm.

[0015] Furthermore, the drive mechanism includes a second rotating arm, a push arm, and an actuator; one end of the second rotating arm has an annular connecting hole for connecting with the rotating shaft, and the other end of the second rotating arm is connected to the actuator through the push arm; the actuator pushes the push arm, thereby causing the solidified second rotating arm and the first rotating arm to move together around the rotating shaft.

[0016] Furthermore, the push arm is a T-shaped push arm.

[0017] Furthermore, a spring hole is provided on the second rotating arm. The spring hole is used to accommodate springs with different damping coefficients. The spring is used in combination with the actuator to realize the reciprocating operation of the resonant cavity.

[0018] Furthermore, the second rotating arm and the push arm are respectively provided with optical coupler limit mounting holes, which are used to install limit switches of different precision.

[0019] A second aspect of the present invention provides a method for adjusting the position of a tunable laser source resonant cavity mirror, based on a device for adjusting the position of a tunable laser source resonant cavity mirror, comprising:

[0020] The tilt state of the reflector is adjusted by the reflector support arm and the mounting hole, which is placed on the reflector support block.

[0021] Fine-tune the pitch state of the mirror according to the resonant output power of the tuning source, and lock the bolts in the assembly holes after reaching the expected state;

[0022] Adjust the included angle between the first rotating arm and the second rotating arm according to the required wavelength tuning range or line width, and fix the included angle after reaching the expected state;

[0023] Achieve the damping matching movement of the actuator through damping matching to achieve low-jitter control;

[0024] Install the optical coupler limit as required to provide high-precision positioning at the initial and termination ends of the cavity length.

[0025] One or more of the above technical solutions have the following beneficial effects:

[0026] (1) The position adjustment device for the mirror of the tunable laser source resonator provided by the present invention is of a split design, which can reduce the machining difficulty. In the LM-TLS, the design with variable included angle, adjustable resonant state of the resonant mirror, and multi-position damping matching solves the problem that the fixed resonant characteristic output realized by the traditional assembly method of the integral laser tuning source rotor with a fixed included angle and the external cavity laser tuning source cavity is difficult to meet the user's requirements for various specifications (line width, power, tuning range, etc.) of the LM-TLS; at the same time, it reduces the complexity of the test system and saves the operation and maintenance cost.

[0027] (2) The "product"-shaped resonant mirror support block design in the present invention can effectively reduce the mirror surface deformation introduced during the bonding process of the tuning mirror.

[0028] (2) In the present invention, the rigid screws and the rotating shaft are interconnected, which is convenient for the replacement or upgrade of resonant mirrors of different specifications and the realization of customization of different resonant output characteristics.

[0029] The advantages of the additional aspects of the present invention will be partially given in the following description, partially become obvious from the following description, or be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The specification drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation of the present invention.

[0031] Figure 1 It is a structural diagram of the position adjustment device for the mirror of the tunable laser source resonator in Embodiment 1.

[0032] Figure 2 It is a top view of the position adjustment device for the mirror of the tunable laser source resonator in Embodiment 1.

[0033] Figure 3 It is a front view of the position adjustment device for the mirror of the tunable laser source resonator in Embodiment 1.

[0034] Figure 4 This is a front view of the mirror support mechanism of Embodiment 1.

[0035] Figure 5 This is a rear view of the mirror support mechanism of Embodiment 1.

[0036] Figure 6 This is a left-side view of the mirror support mechanism of Embodiment 1.

[0037] Figure 7 This is a right-side view of the mirror support mechanism of Example 1.

[0038] Figure 8 This is a top view of the mirror support mechanism of Embodiment 1.

[0039] Figure 9 This is a front view of the actuation mechanism of Example 1.

[0040] Figure 10 This is a rear view of the actuation mechanism of Example 1.

[0041] Figure 11 This is a left-side view of the actuation mechanism of Example 1.

[0042] Figure 12 This is a right-side view of the actuation mechanism of Example 1.

[0043] Figure 13 This is a top view of the actuation mechanism of Example 1.

[0044] Figure 14 This is a side view of the push arm in Example 1.

[0045] In the figure, 1 is the reflector support arm, 101 is the mounting hole, 2 is the reflector support plate, 201 is the reflector support block, 3 is the first rotating arm, 4 is the rotating shaft, 5 is the second rotating arm, 501 is the spring hole, 6 is the push arm, 601 is the horizontal plate, 602 is the vertical plate, and 603 is the optical coupler limiting mounting hole. Detailed Implementation

[0046] The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

[0047] Example 1

[0048] like Figures 1 to 3 As shown, the present invention proposes a position adjustment device for a tunable laser source resonant cavity mirror, comprising: a mirror support mechanism and an actuation mechanism located below the mirror support mechanism;

[0049] like Figures 4 to 8As shown, the reflector support mechanism includes: a reflector support arm 1, a first rotating arm 3, and a reflector support plate 2; the lower end of the reflector support arm 1 is connected to one end of the first rotating arm 3, and the other end of the first rotating arm 3 is rotatably connected to the actuation mechanism; specifically, an annular rotating hole is opened at the other end of the first rotating arm 3, and a rotating shaft 4 is sleeved in the annular rotating hole, with the bottom end of the rotating shaft 4 connected to the actuation mechanism; the rotating shaft 4 is typically an angular contact bearing; during the initial tuning of the tuning source, the expected angle is changed by the relative change of the axial position of the first rotating arm 3 and the second rotating arm 5, thereby achieving a change in the overall cavity length, and the change in cavity length will cause changes in parameters such as linewidth, power, and tuning range;

[0050] The upper end of the reflector support arm 1 is connected to the reflector support plate 2, and three reflector support blocks 201 are provided on one side of the reflector support plate 2; wherein, the first reflector support block and the second reflector support block are coaxially arranged at the upper edge of the side of the reflector support plate 2, and the third reflector support block is arranged at the lower edge of the side of the reflector support plate 2.

[0051] Furthermore, the first and second reflector support blocks are spaced a certain distance apart, and the third reflector support point is located at the midpoint of the lower edge of the side of the reflector support plate 2.

[0052] A through bolt hole 101 is provided on the reflector support arm 1, and a bolt is installed in the bolt hole 101. The reflector support arm 1 is fixedly connected to the first rotating arm 3 by the bolt. When finely adjusting the resonance state of the inner and outer cavities of the tuning source, the pitch change of the resonant mirror is adjusted by the bolt between the reflector support arm 1 and the first rotating arm 3 to optimize the cavity loss and achieve power output adjustment within a certain range.

[0053] like Figures 9 to 13 As shown, the drive mechanism includes a second rotating arm 5, a T-shaped push arm 6, and an actuator; one end of the second rotating arm 5 has an annular rotating hole, and the second rotating arm 5 is connected to the bottom end of the rotating shaft 4 through the annular rotating hole; the other end of the second rotating arm 5 is connected to the actuator through the T-shaped push arm 6, and the actuator is a stepper motor; the actuator pushes the T-shaped push arm, which in turn drives the solidified second rotating arm 5 and the first rotating arm 3 to move together around the rotating shaft 4, and realizes reciprocating motion within a certain distance through the optocoupler limit switch, thereby realizing the cyclic lasing output of the tuned source;

[0054] When the optocoupler limit switch is unobstructed, it is in the open state. In this state, the actuator pushes the T-shaped push arm 6 around the axis, changing the cavity length and achieving different wavelength outputs. When the optocoupler limit switch is obstructed, i.e., the T-shaped push arm 6 pushed by the actuator moves to a preset position, the optocoupler limit switch is in the closed state. At this point, the system completes one scan by default, and the command flips. The optocoupler limit switch is used for starting position positioning, and its positioning position is affected by the actuator position.

[0055] The four holes on the second rotating arm 5 are reserved for mounting springs. The spring hole 501 is used to match springs with different damping coefficients. The spring is used in combination with the actuator to realize the reciprocating motion of the resonant cavity. The actuator is used to push the T-shaped push arm 6 and combine it with the optocoupler switch to realize the reciprocating motion. The spring is used to realize damping matching, that is, through one of the four mounting holes on 5, the force balance of the T-shaped push arm 6 during the push and pull of the actuator is realized, thereby ensuring the smooth movement of the reflector and realizing mode-skipping output.

[0056] The second rotating arm 5 and the T-shaped push arm 6 (as shown) Figure 14 The second rotating arm 5 and the T-shaped push arm 6 are provided with optical coupler limiting mounting holes 601, which facilitates the expansion of the high performance index of the laser tuning source. There are two optical coupler limiting mounting holes 601 on the second rotating arm 5 and the T-shaped push arm 6. The main function of the optical coupler limiting mounting holes is to install limit switches of different precision according to the actual needs of the user, thereby ensuring accurate feedback of the start wavelength and the end wavelength, which helps to expand the output wavelength accuracy index of the tuning source.

[0057] Example 2

[0058] This embodiment provides a method for adjusting the position of a tunable laser source resonant cavity mirror, based on the tunable laser source resonant cavity mirror position adjustment device of Embodiment 1, including:

[0059] Step 1: The reflector, which is bonded to the reflector support block 201 using optical ultraviolet adhesive or glass welding, is adjusted in pitch by means of reflector support arm 1 and mounting hole 101.

[0060] Step 2: Fine-tune the pitch state of the reflector according to the resonant output power of the tuning source, and tighten the bolt inside the mounting hole 101 after reaching the expected state.

[0061] Step 3: Adjust the angle between the first rotating arm 3 and the second rotating arm 5 according to the required wavelength tuning range or linewidth, and solidify the angle after the expected state is achieved.

[0062] Step 4: Achieve damped matching motion of the actuator through damping matching to achieve low jitter control;

[0063] The spring is used to achieve damping matching, that is, through one of the four mounting holes on the second rotating arm 5, the force balance of the T-shaped push arm 6 during the push and pull of the actuator is achieved, thereby ensuring the smooth movement of the reflector, reducing the random fluctuations in the external cavity length caused by the jitter during the movement of the reflector, and achieving mode-free, high wavelength accuracy output.

[0064] Step 5: Install the optocoupler limiter as needed to provide high-precision positioning of the initial and final cavity lengths.

[0065] The optocoupler limiter is actually a metal baffle that moves back and forth with the second rotating arm 5 driven by the actuator to achieve the initial and final cavity length position positioning. Users can choose products with different positioning accuracy according to their needs such as cost to ensure the required positioning accuracy.

[0066] By optimizing each of the above workflows, the position of the reflector is ensured to be optimal, thereby achieving high-performance output from the tuning source.

[0067] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A position adjustment device for a resonant cavity mirror of a tunable laser source, characterized in that, include: A mirror support mechanism and an actuation mechanism located below the mirror support mechanism; The mirror support mechanism includes: a mirror support arm, a first rotating arm, and a mirror support plate; The lower end of the reflector support arm is connected to one end of the first rotating arm, and the other end of the first rotating arm is rotatably connected to the actuation mechanism via a rotating shaft; the upper end of the reflector support arm is connected to the reflector support plate, and a reflector support block is provided on one side of the reflector support plate; The actuation mechanism includes a second rotating arm, a push arm, and an actuator; one end of the second rotating arm has an annular connection hole for connecting with the rotating shaft, and the other end of the second rotating arm is connected to the actuator through the push arm; the actuator pushes the push arm, thereby causing the solidified second rotating arm and the first rotating arm to move together around the rotating shaft.

2. The position adjustment device for the resonant cavity mirror of a tunable laser source according to claim 1, characterized in that, The number of the reflector support blocks is 3.

3. The position adjustment device for the resonant cavity mirror of a tunable laser source according to claim 2, characterized in that, The first and second mirror support blocks are coaxially arranged at the upper edge of the side of the mirror support plate, and the third mirror support block is arranged at the lower edge of the side of the mirror support plate.

4. The position adjustment device for the resonant cavity mirror of a tunable laser source according to claim 3, characterized in that, The first and second mirror support blocks are spaced a certain distance apart, and the third mirror support block is located at the midpoint of the lower edge of the side of the mirror support plate.

5. The position adjustment device for the resonant cavity mirror of a tunable laser source according to claim 1, characterized in that, Bolt holes are provided on the side of the reflector support arm, and bolts for fixing the first rotating arm are provided in the bolt holes; the pitch angle of the reflector is adjusted by the bolts between the reflector support arm and the first rotating arm.

6. The position adjustment device for the resonant cavity mirror of a tunable laser source according to claim 1, characterized in that, The push arm is a T-shaped push arm.

7. The position adjustment device for the resonant cavity mirror of a tunable laser source according to claim 1, characterized in that, A spring hole is provided on the second rotating arm. The spring hole is used to accommodate springs with different damping coefficients. The spring is used in combination with the actuator to realize the reciprocating operation of the resonant cavity.

8. The position adjustment device for the resonant cavity mirror of a tunable laser source according to claim 1, characterized in that, The second rotating arm and the push arm are respectively provided with optical coupler limit mounting holes, which are used to install limit switches of different precision.

9. A method for adjusting the position of a tunable laser source resonant cavity mirror, based on the position adjustment device for the tunable laser source resonant cavity mirror according to any one of claims 1-8, characterized in that, include: The tilt state of the reflector is adjusted by the reflector support arm and the mounting hole, which is placed on the reflector support block. Fine-tune the pitch of the reflector according to the resonant output power of the tuning source, and tighten the bolts in the mounting hole after reaching the expected state. Adjust the angle between the first and second rotating arms according to the required wavelength tuning range or linewidth, and then fix the angle after the expected state is achieved. Low-jitter control is achieved by damping matching to achieve damping matching motion of the actuator; Install optical coupler limits as needed to provide high-precision positioning of the initial and final cavity lengths.

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