A laser polarization degree testing device

Abstract

The application provides a laser polarization degree testing device applied to the technical field of detection, which comprises a thin film circuit, the surface of the thin film circuit is provided with an electrode contact point of a laser, a laser limiting device, the laser limiting device is provided with a clamping groove on a bearing surface, a conductive assembly, the conductive assembly is arranged on the laser limiting device close to the bearing surface, the conductive assembly comprises a support structure which can move up and down along a guide rail perpendicular to the bearing surface and at least two conductive contacts, the conductive contacts are fixed to the support structure and vertically correspond to the position of the electrode contact point, a rotating table, a through hole is formed in the rotating table shaft, a polarizer is fixedly arranged on the receiving surface of the rotating table, a photodiode, the photodiode is vertically arranged in the light output direction of the polarizer, the photosensitive surface of the photodiode is coaxial with the rotating table, and a controller, the controller is electrically connected with the conductive assembly, the rotating table and the photodiode through wires. The universality and operation convenience of the device can be enhanced.

Description

Technical Field

[0001] The present application relates to the field of detection technology, and in particular to a laser polarization degree testing device. Background Art

[0002] In the field of semiconductor micro-electro-mechanical systems (MEMS) device integration, lasers have a significant impact on the overall performance of the optical path. However, due to the small core size of some lasers, such as vertical-cavity surface-emitting lasers (VCSELs), their performance testing is difficult to operate and the test consistency is difficult to control. In traditional test systems, each time the test sample is changed, each component must be recalibrated according to the laser to be tested, resulting in low test efficiency. Summary of the Invention

[0003] An embodiment of the present application provides a laser polarization degree testing device to solve the problem of low testing efficiency of traditional laser polarization degree testing devices.

[0004] In order to solve the above technical problems, an embodiment of the present application provides a laser polarization degree testing device, comprising: a thin film circuit, wherein a first surface of the thin film circuit is provided with an electrode contact of the laser;

[0005] A laser limiting device, wherein the laser limiting device has a slot on a bearing surface for fixing and placing the thin film circuit;

[0006] A conductive component is provided on the laser limiting device in a direction close to the bearing surface, the conductive component comprises a support structure movable up and down along a guide rail perpendicular to the bearing surface and at least two conductive contacts, the conductive contacts being fixed to the support structure and corresponding perpendicularly to the positions of the electrode contacts. When testing the polarization degree of the laser, the conductive component moves in a direction close to the card slot so that the conductive contacts contact the electrode contacts and form an electrical connection.

[0007] A rotating platform, wherein a through hole is provided at the axis of the rotating platform, and a polarizer is fixedly arranged on the receiving surface of the rotating platform;

[0008] A photodiode, wherein the photodiode is arranged perpendicular to the light emitting direction of the polarizer, and the photosensitive surface of the photodiode is coaxial with the rotating stage;

[0009] A controller is electrically connected to the conductive component, the rotating stage and the photodiode through wires. The controller is used to control the rotation of the rotating stage, supply power to the conductive component, collect the output signal of the photodiode and calculate the polarization degree of the laser.

[0010] One of the above technical solutions has the following advantages or beneficial effects:

[0011] In an embodiment of the present application, a thin film circuit is provided with a laser electrode contact on the first surface of the thin film circuit; a laser limiting device is provided with a slot on the bearing surface for fixing the thin film circuit; a conductive component is provided at a position of the laser limiting device close to the bearing surface, the conductive component includes a support structure that can move up and down along a guide rail perpendicular to the bearing surface and at least two conductive contacts, the conductive contacts are fixed to the support structure and correspond vertically to the position of the electrode contacts. When testing the polarization degree of the laser, the conductive components are arranged at a position close to the bearing surface of the laser limiting device. The component moves in a direction close to the card slot so that the conductive contact contacts the electrode contact and forms an electrical connection; a rotating table, a through hole is provided at the axis of the rotating table, and a polarizer is fixedly arranged on the receiving surface of the rotating table; a photodiode, the photodiode is arranged perpendicular to the light emitting direction of the polarizer, and the photosensitive surface of the photodiode is coaxial with the rotating table; a controller, the controller is electrically connected to the conductive component, the rotating table and the photodiode through wires, and the controller is used to control the rotation of the rotating table, supply power to the conductive component, collect the output signal of the photodiode and calculate the polarization degree of the laser. The embodiment of the present application uses the slots of the laser limiting device to accurately position the thin film circuit, and cooperates with the vertically movable conductive contacts to achieve reliable contact and electrical connection of the microelectrode, which can reduce the unstable contact during the testing of small-sized devices. The coaxial layout of the axis through hole of the rotating table, the polarizer and the photodiode ensures that the laser beam is vertically incident on the photosensitive surface, reduces the optical path offset error, and improves the accuracy of optical signal acquisition. In addition, the controllable movement of the conductive component along the vertical guide rail is compatible with laser electrode layouts of different specifications, enhances the versatility and ease of operation of the device, and thus improves the test efficiency of the polarization degree of lasers of different specifications. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0013] Figure 1Schematic diagram of the structure of the laser polarization test device provided in the embodiment of the present application. DETAILED DESCRIPTION

[0014] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0015] like Figure 1 As shown, an embodiment of the present invention provides a laser polarization degree testing device, such as Figure 1 Shown, including:

[0016] A thin film circuit 2, wherein a first surface of the thin film circuit 2 is provided with an electrode contact of a laser;

[0017] A laser limiting device 3, wherein the laser limiting device 3 has a slot on the bearing surface for fixing and placing the thin film circuit 2;

[0018] A conductive component 1 is provided at a position close to the bearing surface of the laser limiting device 3. The conductive component 1 includes a support structure that can move up and down along a guide rail perpendicular to the bearing surface and at least two conductive contacts. The conductive contacts are fixed to the support structure and correspond perpendicularly to the positions of the electrode contacts. When testing the polarization degree of the laser, the conductive component 1 moves in a direction close to the card slot so that the conductive contacts contact the electrode contacts and form an electrical connection.

[0019] A rotating platform 5, wherein a through hole is provided at the axis of the rotating platform 5, and the polarizer is fixedly arranged on the receiving surface of the rotating platform 5;

[0020] A photodiode 6, wherein the photodiode 6 is arranged perpendicular to the light emitting direction of the polarizer, and the photosensitive surface of the photodiode 6 is coaxial with the rotating stage 5;

[0021] The controller 7 is electrically connected to the conductive component 1, the rotating stage 5 and the photodiode 6 through wires. The controller 7 is used to control the rotation of the rotating stage 5, supply power to the conductive component 1, collect the output signal of the photodiode 6 and calculate the polarization degree of the laser.

[0022] In the embodiment of the present invention, Figure 1Taking the structural form as an example, the electrode of the above-mentioned laser can be electrically connected to the electrode contact of the thin film circuit 2 by welding or wire bonding. For example, it can be directly welded to the first surface of the thin film circuit 2 by surface mounting technology, and the positive electrode can be connected to the positive electrode welding point of the above-mentioned thin film circuit 2 by gold wire bonding; in addition, the electrode of the laser and the electrode contact of the thin film circuit 2 can also be connected by anisotropic conductive glue, and the conductive glue can form a conductive path after high-temperature curing, or by other methods. This embodiment of the application does not make specific limitations.

[0023] The thin film circuit 2 is mechanically secured by the slot, ensuring that the electrode contacts correspond to the conductive contacts. In some optional embodiments, the inner wall of the slot may be provided with elastic retaining protrusions to provide a horizontal preload when the thin film circuit 2 is placed in the slot. The bottom of the slot may also be provided with locating pins, with locating holes defined at corresponding positions on the thin film circuit 2. The locating pins and holes can be used to enhance the mechanical fixation of the thin film circuit 2.

[0024] The above-mentioned conductive component 1 can move along a guide rail perpendicular to the bearing surface to achieve contact or separation with the electrode contact. The above-mentioned guide rail can be designed in the entire shell 8. The above-mentioned support structure can be fixedly connected to a pressing rod at the top, and the pressing rod extends to the outside of the shell 8 of the device and forms an operating handle; the guide rail outer sleeve is provided with a reset spring. When the operating handle is manually pressed downward, the support structure moves downward along the guide rail, and the conductive contact contacts the electrode contact; in some optional embodiments, a limit buckle can be provided between the pressing rod and the shell 8, which is used to lock the position of the pressing rod when the conductive contact contacts the electrode contact.

[0025] In other optional embodiments, the conductive contact may include a main probe and at least one auxiliary probe, wherein the auxiliary probe is longer than the main probe; the auxiliary probe may be connected to the support structure via an independent elastic structure, wherein the elastic coefficient of the elastic structure is less than the elastic coefficient of the return spring and the elastic structure of the main probe; when the operating handle is manually pressed, the auxiliary probe contacts the electrode contact before the main probe to detect the contact resistance; if the contact resistance exceeds a preset threshold, a prompt may be provided to readjust the position of the thin film circuit 2. After the operating handle is released, the return spring drives the support structure back to its initial position.

[0026] In some other optional embodiments, the guide rail can be a linear ball guide rail, the support structure can be slidably connected to the guide rail through a slider, and a spring buffer mechanism can also be provided between the support structure and the guide rail to provide buffering when the conductive contact contacts the electrode contact to avoid damaging the electrode surface.

[0027] The polarization plate is fixed to the receiving surface of the rotating table 5, the rotating table 5 axial hole ensures the coaxiality of the light path, and the fixing mode of the polarization plate is not specifically limited in the embodiment of the application. The polarization plate can be pasted on the receiving surface of the rotating table 5 by optical glue; or a ring groove can be arranged on the receiving surface of the rotating table 5, the edge of the polarization plate is embedded in the groove and fixed by a compression ring. Different fixing modes do not affect the realization of the basic function of the laser polarization degree testing device in the embodiment of the application. The photodiode 6 is vertically arranged in the light output direction of the polarization plate, and the photosensitive surface is coaxial with the rotating table 5. Specifically, the photodiode 6 can be fixed below the rotating table 5 by a metal support, or a diaphragm can be arranged around the photodiode 6 to limit the angle range of the incident light and improve the collection accuracy of the optical signal.

[0028] The controller 7 controls and transmits signals of the conductive assembly 1, the rotating table 5 and the photodiode 6 through wires. The material, quality and specific model of the wires are not specifically limited in the embodiment of the application.

[0029] Exemplarily, the complete use steps of the laser polarization degree testing device can be as follows:

[0030] The controller 7 powers on the laser polarization degree testing device and controls the rotating table 5 to start rotating at a constant speed;

[0031] Start the controller 7 and start the test program;

[0032] Place the thin film circuit 2 with the VCSEL laser welded on it in the fixed slot in the middle;

[0033] Press the support structure of the conductive assembly 1 to make the conductive contact and the electrode of the thin film circuit 2 conductive;

[0034] The photodiode 6 converts the optical signal into an electrical signal and feeds back the test value through the controller 7.

[0035] In some optional embodiments, the controller 7 includes a test program control circuit system, which can power the laser and process the light intensity received by the photodiode 6 into a numerical value.

[0036] In this embodiment, the thin film circuit 2 is precisely positioned by the card slot of the laser limit device 3, and the vertically movable conductive contacts are used to achieve reliable contact and electrical connection of the microelectrode, which can reduce the unstable contact during the testing of small-sized devices. The coaxial layout of the axial through hole of the rotating table 5, the polarizer and the photodiode 6 ensures that the laser beam is vertically incident on the photosensitive surface, reduces the optical path offset error, and improves the accuracy of optical signal acquisition. In addition, the controllable movement of the conductive component 1 along the vertical guide rail is compatible with laser electrode layouts of different specifications, enhances the versatility and ease of operation of the device, and also improves the test efficiency.

[0037] Optionally, the negative electrode of the laser is welded to the second surface of the thin film circuit 2 and connected to the negative contact of the electrode contact through a first through hole, and the positive electrode of the laser is transferred to the positive welding point of the second surface by wire bonding and connected to the positive contact of the electrode contact through a second through hole.

[0038] In this embodiment, the negative electrode of the above-mentioned laser can be directly fixed to the second surface of the thin film circuit 2 through a welding process, such as reflow soldering, and the negative electrode solder joint on the above-mentioned second surface is electrically connected to the negative electrode contact on the first surface through a first through-hole vertically penetrating the thin film circuit 2. The inner wall of the first through-hole can be plated with a metal layer to form a conductive path to ensure that the current is conducted from the negative electrode contact to the negative electrode of the laser through the through-hole. The positive electrode of the above-mentioned laser can be connected to the positive electrode solder joint on the second surface by gold wire bonding. The positive electrode solder joint can be electrically connected to the positive electrode contact on the first surface through the second through-hole, so that the current is conducted from the positive electrode contact to the positive electrode of the laser through the through-hole and the gold wire. The size of the above-mentioned through-hole and the thickness of the metal layer are not specifically limited in this embodiment of the application.

[0039] In this embodiment, the laser electrode is led out from the second surface to the first surface through the through-hole structure, which solves the space limitation problem of the one-sided wiring of the thin-film circuit 2 and improves the adaptability to the high-density integrated micro-laser testing. In addition, compared with the traditional surface wiring method, the through-hole connection path is shorter, reducing the signal transmission loss. The electrode contacts are concentrated on the first surface. Through the through-hole transfer technology, the electrode signal can be efficiently led out from the bottom of the device to the test plane, while avoiding light path obstruction or mechanical interference. It is also convenient to uniformly design the layout of the conductive contacts. There is no need to design complex contact structures for the positive and negative poles of the laser respectively, thereby improving the compatibility of the laser polarization test device.

[0040] Of course, a double-sided wire bonding transition structure can also be used, for example, the negative electrode of the laser is connected to the negative electrode solder joint on the second surface of the thin film circuit 2 through gold wire bonding, and the negative electrode solder joint extends to the edge of the thin film circuit 2 through a first metal trace, and is connected to the negative electrode contact on the first surface of the thin film circuit 2 through a lateral wire bonding method; or an embedded bump transition structure can be used, for example, the negative electrode of the laser is connected to the negative electrode bump on the second surface of the thin film circuit 2 through gold-tin eutectic welding, and the negative electrode bump is an embedded structure, and its bottom is directly connected to the negative electrode contact on the first surface through a conductive column that passes through the thin film circuit 2, etc., both of which can realize the connection of the laser electrode and power the laser electrode.

[0041] Optionally, the device further includes a nylon support structure 4 fixedly disposed between the rotating platform 5 and the laser limiting device 3 .

[0042] In this embodiment, the nylon support structure 4 is fixedly connected between the laser limiting device 3 and the rotating table 5, and can form a mechanical support and thermal isolation layer. It ensures that the relative position of the rotating table 5 and the laser limiting device 3 is stable, maintains the coaxiality of the optical path system, and can block the heat transfer from the laser limiting device 3 to the rotating table 5, thereby avoiding the influence of temperature changes on the performance of the polarizer and the photodiode 6. The specific structure and form of the nylon support structure 4 are not specifically limited in the embodiment of the present application. The specific number and specifications of nylon pillars can be selected according to the specific environment and evenly distributed on the edges of the rotating table 5 and the laser limiting device 3. Of course, other distribution methods can also be used; an integral nylon pad can also be used, with a positioning groove on the upper surface to cooperate with the rotating table 5 and a screw hole on the lower surface to fix it to the laser limiting device 3. Different forms of nylon support structures 4 do not affect the realization of the basic functions of the laser polarization test device in the embodiment of the present application.

[0043] In this embodiment, the nylon support structure 4 plays a role in mechanical support, thermal isolation, electromagnetic compatibility, etc. through the coordination of material selection and structural design, thereby improving the stability of the optical path system and the controllability of the temperature environment in the laser polarization test.

[0044] In addition, a polyetheretherketone support structure can also be used, which is in the shape of a hollow cylinder, with the upper and lower end faces fixed to the bottom surface of the rotating table 5 and the top surface of the laser limiting device 3 respectively by countersunk screws; the outer diameter of the polyetheretherketone support structure is aligned with the edge of the rotating table 5, and the inner diameter is larger than the light output aperture of the laser. The upper and lower end faces can be pre-embedded with metal inserts and fixed by stainless steel screws. The inner surface of the support structure can be sprayed with a black matte coating to reduce the interference of stray light reflection on the photodiode 6. A ceramic air-floating support structure can also be used, evenly distributed between the rotating table 5 and the laser limiting device 3; a hemispherical air-floating bearing is provided at the top of each ceramic pillar, and a flat air-floating pad is provided at the bottom to achieve contactless support of the rotating table 5. Or not adding an additional support structure does not affect the realization of the basic functions of the laser polarization test device in the embodiment of the present application.

[0045] Optionally, the conductive contact is a spring probe, the supporting structure is a plastic top plate, and the spring probe passes through and is fixedly connected to the plastic top plate.

[0046] In this embodiment, the probe body can be made of beryllium copper (BeCu) or phosphor bronze (CuSn). In some optional embodiments, the surface can also be gold-plated to ensure low resistance and corrosion resistance. The internal spring can be made of stainless steel or nickel alloy, and the probe tip can adopt a tapered or wedge-shaped design. When the plastic top plate is pressed down, the spring probe contacts the electrode contact and compresses, and the elastic force generated by the spring ensures stable contact. The compressible nature of the probe compensates for machining tolerances and surface irregularities.

[0047] Compared to metal top plates, the aforementioned plastic top plate is lighter, reducing the load on the drive mechanism and increasing movement speed. The non-metallic material avoids the electromagnetic shielding effect caused by metal structures, reducing interference with weak photocurrent signals. The spring probe's dynamic compensation mechanism reduces contact resistance fluctuations and improves electrical connection stability. The spring probe's plug-in life is also longer than that of traditional rigid probes, reducing the maintenance cost of frequent probe replacement. In some optional embodiments, the plastic top plate can have stepped holes, and the probes are secured by an interference fit.

[0048] In this embodiment, the combination of the spring probe and the plastic top plate solves the problems of contact reliability and electromagnetic compatibility at the same time, improves the adaptability of the laser polarization test device to the test scenarios of high-precision, small-size lasers, and to a certain extent, improves the reliability of the electrical connection of the laser electrodes, improves the stability of the laser power supply, and further improves the test accuracy of the laser polarization.

[0049] In addition, a cantilever beam elastic probe can also be used, with a printed circuit board (PCB) as the supporting structure. The cantilever beam elastic probe is connected to the internal wiring of the PCB through metallized vias, and the probe array is integrally formed with the pads on the surface of the PCB. A tungsten needle tip can also be used as a conductive contact, fixed to the moving end of the piezoelectric ceramic driver. The supporting structure is an alumina ceramic substrate with an integrated piezoelectric drive circuit and signal conditioning circuit. The piezoelectric driver has a built-in strain gauge sensor to form a force feedback closed-loop control. The piezoelectric ceramic driver achieves the displacement of the conductive component 1 through closed-loop control. The selection of different forms of conductive components 1 and support structures does not affect the realization of the basic functions of the laser polarization test device in the embodiment of the present application.

[0050] Optionally, the laser limiting device 3 is made of metal material, and a heating resistance wire is fixedly arranged at the bottom of the slot.

[0051] The above-mentioned metal material can be aluminum alloy, copper alloy or other metal materials. The embodiment of the present invention does not make any specific restrictions on this. A metal material with high thermal conductivity can be used to quickly and evenly conduct the heat generated by the heating resistor to the card slot area. In some optional embodiments, the laser limiting device 3 is a metal material fixed card slot, a carrier film circuit 2, and cooperates with the nylon support structure 4 to form a "heating-insulation" temperature control unit. A heating resistor is fixedly provided at the bottom of the above-mentioned card slot. The resistor can be close to the inner wall of the bottom of the card slot, or it can be arranged in a serpentine or grid shape. The specific material of the resistor is also not limited in the embodiment of the present application. A high-temperature resistant and anti-oxidation entry material, such as nickel-chromium alloy, can be used. In some optional embodiments, it can be adhered to the bottom of the card slot by a high-temperature resistant glue, such as silicone resin, or embedded in a metal groove to avoid local overheating caused by displacement.

[0052] For example, the power supply module of controller 7 applies voltage to the heating resistor, generating Joule heating. The polarization degree of the VCSEL laser can change with temperature. By stabilizing the test temperature at the target value through the heating resistor, the influence of temperature fluctuations on the measurement results can be eliminated. Furthermore, after heating, the thermal expansion of the thin film circuit 2 and the card slot is consistent, reducing the contact gap. Combined with the elastic compensation of the spring probe, the stability of the connection between the conductive contact and the electrode contact can be enhanced at high temperatures.

[0053] In this embodiment, the metal material of the laser limit device 3 and the heating resistor wire at the bottom of the slot provide a stable temperature testing environment for the laser through efficient heat conduction and temperature control, thereby improving the accuracy and repeatability of polarization measurement under different temperature conditions.

[0054] Furthermore, the bottom of the slot can be provided with evenly distributed rectangular grooves, each embedded with an independently controlled multi-layer ceramic heater secured by thermally conductive silicone. Alternatively, the bottom of the slot can be designed as a mirrored reflective surface, with the heating system comprising an infrared LED array located below the device, focusing infrared light onto the slot area via a parabolic reflector, while an infrared absorbing coating is affixed to the bottom of the thin-film circuit 2 to achieve non-contact heating. Different heating methods do not affect the basic functionality of the laser polarization test device in the embodiments of this application.

[0055] Optionally, the photodiode 6 is fixed by a support, and the photodiode 6 is located in the light emitting direction of the polarizer.

[0056] The embodiment of the present application does not specifically limit the shape, size and specific material of the pillar. In some optional embodiments, the support structure can be surface treated, such as by black anodizing or chemical nickel plating, to reduce stray light reflection. In some optional embodiments, the bottom of the pillar can be rigidly connected to the base of the device through a threaded hole, and the top can be fixed to the photodiode 6 through an elastic clamp. A three-dimensional adjustment mechanism can also be provided at the top of the pillar, such as a ball joint and a locking nut, to achieve coaxial calibration of the photosensitive surface of the photodiode 6 and the axis of the rotating table 5. The photodiode 6 can also be fitted to the top of the pillar by thermally conductive silicone, and a radial force can be applied with a stainless steel clamp to avoid loosening to a certain extent; the pillar fixing structure improves the positioning accuracy and stability of the photodiode 6 in complex environments to a certain extent through the combination of material selection and mechanical design, and improves the accuracy of optical signal acquisition.

[0057] In addition, the photodiode 6 can also be fixed by an integrated aluminum alloy flexible hinge cantilever, which consists of a rigid section at the root, a flexible curved section in the middle, and an end mounting platform; the photodiode 6 can also be installed on a permanent magnet base, and the permanent magnet and the electromagnet array on the base of the device form a magnetic levitation support, which triggers the mechanical locking mechanism when the power is off to ensure that the photodiode 6 lands smoothly into the protective groove to avoid collision damage.

[0058] Optionally, the controller 7 includes a power supply module, a rotation control module, a data acquisition module and a calculation module;

[0059] The power supply module is electrically connected to the conductive component 1 through a first wire, and is used to supply power to the conductive component 1; the rotation control module is electrically connected to the drive motor of the rotating stage 5 through a second wire, and is used to drive the rotating stage 5 to rotate; the data acquisition module is electrically connected to the photodiode 6 through a third wire, and the data acquisition module includes a preamplifier and an analog-to-digital converter; the calculation module is respectively connected to the power supply module, the rotation control module and the data acquisition module through an internal bus, and is used to calculate the polarization degree of the laser.

[0060] In this embodiment, the controller 7 can form a closed loop with the conductive component 1 via a first conductor, using a constant current source or constant voltage source for power supply. In some optional embodiments, a built-in filter circuit can be included to suppress the effects of high-frequency interference on the laser polarization state. A second conductor connects to the servo motor of the rotating stage 5, driving the polarizer to rotate at a fixed angular velocity. The photodiode 6 synchronously collects light intensity signals to construct a light intensity-angle relationship curve.

[0061] The above-mentioned data acquisition module can serve as a conversion bridge for photoelectric signals, and the preamplifier can adopt a low-noise design to adapt to the current output of the photodiode 6; in some optional embodiments, the above-mentioned third wire can adopt a twisted shielded pair cable, and an RC filter circuit can be set at the input end to suppress ambient light noise and power frequency interference.

[0062] The calculation module can be understood as the intelligent core of polarization calculation, which reads three pieces of data in real time through the internal bus: the output voltage or current of the power supply module, the real-time angle of the rotation control module, and the digitized light intensity signal of the data acquisition module.

[0063] For example, the power supply module starts to power the laser in a constant current mode, the rotation control module drives the polarizer to zero, the photodiode 6 collects the initial light intensity, and the rotating stage 5 rotates in steps at a preset angular velocity. Every time it reaches an angle point, it triggers the synchronous collection of the light intensity signal, and the calculation module collects and calculates the polarization degree in real time. In some optional embodiments, if the result exceeds the set threshold, a second scan can be automatically triggered, and the polarization degree value and curve can be displayed through a human-machine interface such as a touch screen, and the data can be stored in a built-in memory. In this embodiment, through modular design, the controller 7 achieves deep integration of power supply, motion control, signal acquisition, and data processing, which not only improves measurement accuracy but also enhances system scalability through standardized interfaces.

[0064] In addition, other unit modules can be expanded in the controller 7, or one of the above modules can be reduced to be controlled independently of the controller 7. The implementation method of this application does not make any specific limitations on this.

[0065] Optionally, an elastic limiting protrusion is provided on the inner wall of the slot.

[0066] In this embodiment, the specific material of the elastic limiting protrusion is not specifically limited in this application embodiment and can be silicone, thermoplastic elastomer, or nylon plus elastic fiber. When the thin film circuit 2 is inserted into the slot, the protrusion is squeezed and elastically deformed, generating a radial restoring force, which can lock the thin film circuit 2 to prevent axial movement. In some optional embodiments, the surface of the protrusion can be designed to be serrated to increase the friction coefficient and improve vibration resistance. In addition, buckles or guide grooves can be used instead of elastic limiting protrusions to achieve the limiting effect of thin film circuit 2.

[0067] In this embodiment, by providing elastic limiting protrusions on the inner wall of the card slot, different batches of thin film circuits 2 can be stably installed, improving positioning accuracy. The flexible material can avoid scratches on the edges of the thin film circuit 2 caused by rigid contact to a certain extent. In addition, the installation can be completed by blind insertion without the need for additional fasteners, which reduces test time and improves test efficiency.

[0068] Optionally, the lower end surface of the conductive contact is a gold-plated hemispherical surface.

[0069] In this embodiment, the gold plating's oxidation resistance and low contact resistance ensure long-term conduction reliability, making it particularly suitable for high-frequency signal transmission, thereby reducing signal loss. The hemispherical curvature allows for insertion angle deviation and positional tolerance, reducing mechanical assembly precision requirements and making it more adaptable to automated blind-mating scenarios. Furthermore, spherical contact wear is less than flat contact wear, allowing it to be combined with elastic structures such as spring probes to extend mating life.

[0070] Of course, the lower end surface of the conductive contact can also be selected into other shapes and materials according to needs, such as a silver-plated boss type or a conductive rubber elastic contact, etc.; this embodiment of the present application does not make specific limitations on this.

[0071] Optionally, a temperature sensor is further provided at the bottom of the card slot, and the controller 7 is electrically connected to the temperature sensor. The controller 7 collects temperature data of the card slot in real time and adjusts the power of the heating resistance wire according to a preset temperature threshold.

[0072] In the embodiment of the present application, since a temperature sensor is also provided at the bottom of the card slot, the temperature of the card slot can be precisely controlled through a closed-loop feedback mechanism. A temperature sensor, such as a thermocouple, a platinum resistor or a thermistor, is directly installed at the bottom of the slot, close to the mounting surface of the object to be measured. The above-mentioned temperature sensor can transmit the analog signal to the analog-to-digital conversion module of the controller 7 through a shielded cable. In some optional embodiments, the controller 7 can preset upper and lower temperature limits. When the measured temperature is not within the preset range, the resistance wire is triggered to heat or the heating power of the resistance wire is reduced or cut off. The control method of the resistance wire is not specifically limited in the embodiment of the present application. The power can be adjusted steplessly by changing the power-on duty cycle of the heating resistance wire. A proportional-integral-differential algorithm can also be introduced to dynamically adjust the heating power.

[0073] In addition, a semiconductor refrigeration plate temperature control system or a fluid circulation temperature control system may also be used. Different temperature control methods do not affect the realization of the basic functions of the embodiments of the present application.

[0074] In this implementation, real-time feedback from the temperature sensor is used to achieve temperature-closed-loop control, which improves test efficiency while ensuring equipment reliability. This is particularly suitable for precision instrument scenarios that are sensitive to temperature.

[0075] In the embodiment of the present application, since it includes a thin film circuit, the first surface of the thin film circuit is provided with an electrode contact of the laser; a laser limiting device, the laser limiting device is provided with a slot on the bearing surface for fixing the thin film circuit; a conductive component, the conductive component is arranged at a position close to the bearing surface of the laser limiting device, the conductive component includes a support structure that can move up and down along a guide rail perpendicular to the bearing surface and at least two conductive contacts, the conductive contacts are fixed to the support structure and correspond vertically to the position of the electrode contacts. When testing the polarization degree of the laser, the conductive contacts are fixed to the support structure and correspond vertically to the position of the electrode contacts. The electrical component moves in a direction approaching the card slot so that the conductive contact contacts the electrode contact and forms an electrical connection; a rotating table, a through hole is provided at the axis of the rotating table, and a polarizer is fixedly arranged on the receiving surface of the rotating table; a photodiode, the photodiode is arranged perpendicular to the light emitting direction of the polarizer, and the photosensitive surface of the photodiode is coaxial with the rotating table; a controller, the controller is electrically connected to the conductive component, the rotating table and the photodiode through wires, and the controller is used to control the rotation of the rotating table, supply power to the conductive component, collect the output signal of the photodiode and calculate the polarization degree of the laser. The embodiment of the present application uses the slots of the laser limiting device to accurately position the thin film circuit, and cooperates with the vertically movable conductive contacts to achieve reliable contact and electrical connection of the microelectrode, which can reduce the unstable contact during the testing of small-sized devices. The coaxial layout of the axis through hole of the rotating table, the polarizer and the photodiode ensures that the laser beam is vertically incident on the photosensitive surface, reduces the optical path offset error, and improves the accuracy of optical signal acquisition. In addition, the controllable movement of the conductive component along the vertical guide rail is compatible with laser electrode layouts of different specifications, enhances the versatility and ease of operation of the device, and thus improves the test efficiency of the polarization degree of lasers of different specifications.

[0076] The above description is merely a preferred embodiment of the present application and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of the invention herein is not limited to the technical solutions formed by the specific combination of the above-mentioned technical features, but also encompasses other technical solutions formed by any combination of the above-mentioned technical features or their equivalents without departing from the inventive concept. For example, a technical solution formed by replacing the above-mentioned features with (but not limited to) technical features having similar functions disclosed in this application.

[0077] Except for the technical features described in the specification, the remaining technical features are known technologies to those skilled in the art. In order to highlight the innovative features of the present invention, the remaining technical features will not be described here in detail.

Claims

1. A laser polarization degree testing device, characterized in that: The device comprises: A thin film circuit, wherein a first surface of the thin film circuit is provided with an electrode contact of a laser; A laser limiting device, wherein the laser limiting device has a slot on the bearing surface for fixing and placing the thin film circuit; the inner wall of the slot is provided with an elastic limiting protrusion; The cathode of the laser is welded to the second surface of the thin film circuit and connected to the cathode contact of the electrode contact through the first through hole, and the anode of the laser is transferred to the anode welding point of the second surface by wire bonding and connected to the anode contact of the electrode contact through the second through hole; A conductive component is provided on the laser limiting device in a direction close to the bearing surface, the conductive component comprises a support structure movable up and down along a guide rail perpendicular to the bearing surface and at least two conductive contacts, the conductive contacts being fixed to the support structure and corresponding perpendicularly to the positions of the electrode contacts. When testing the polarization degree of the laser, the conductive component moves in a direction close to the card slot so that the conductive contacts contact the electrode contacts and form an electrical connection. A rotating platform, wherein a through hole is provided at the axis of the rotating platform, and a polarizer is fixedly arranged on the receiving surface of the rotating platform; A photodiode, wherein the photodiode is arranged perpendicular to the light emitting direction of the polarizer, and the photosensitive surface of the photodiode is coaxial with the rotating stage; A controller is electrically connected to the conductive component, the rotating stage and the photodiode through wires. The controller is used to control the rotation of the rotating stage, supply power to the conductive component, collect the output signal of the photodiode and calculate the polarization degree of the laser.

2. The device according to claim 1, characterized in that The device further comprises a nylon supporting structure fixedly arranged between the rotating platform and the laser limiting device.

3. The device according to claim 1, characterized in that The conductive contact is a spring probe, the supporting structure is a plastic top plate, and the spring probe passes through and is fixedly connected to the plastic top plate.

4. The device according to any one of claims 1 to 3, characterized in that The laser limiting device is made of metal material, and a heating resistance wire is fixedly arranged at the bottom of the slot.

5. The device according to any one of claims 1 to 3, characterized in that The photodiode is fixed by a support, and the position of the photodiode is located in the light emitting direction of the polarizer.

6. The device according to any one of claims 1 to 3, characterized in that The controller includes a power supply module, a rotation control module, a data acquisition module and a calculation module; The power supply module is electrically connected to the conductive component via a first wire, and is used to supply power to the conductive component; The rotation control module is electrically connected to the drive motor of the rotating stage through a second wire, and is used to drive the rotating stage to rotate; the data acquisition module is electrically connected to the photodiode through a third wire, and the data acquisition module includes a preamplifier and an analog-to-digital converter; The calculation module is connected to the power supply module, the rotation control module and the data acquisition module respectively through an internal bus, and is used to calculate the polarization degree of the laser.

7. The device according to any one of claims 1 to 3, characterized in that The lower end surface of the conductive contact is a gold-plated hemispherical surface.

8. The device according to claim 4, characterized in that A temperature sensor is also provided at the bottom of the card slot. The controller is electrically connected to the temperature sensor. The controller collects temperature data of the card slot in real time and adjusts the power of the heating resistance wire according to a preset temperature threshold.

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