Front-back symmetrical double-light-source full-automatic switching X-ray diffractometer

Abstract

The invention provides a front-back symmetrical double-light-source full-automatic switching X-ray diffractometer, which comprises a goniometer host provided with a front-side conventional operation space and a rear-side symmetrical space; the first diffraction light path system is mounted in the front side conventional operation space; the second diffraction light path system is mounted in the rear side symmetrical space; and the integrated control system is electrically connected with the goniometer host, the first diffraction light path system and the second diffraction light path system. According to the invention, the first (front-arranged) system is specially used for micro-area or transmission analysis (such as a thin film and a capillary tube sample) requiring short-wavelength and high-collimation light beams; the second (rear) system is specially optimized for rapid phase analysis of a conventional powder sample, so that a user can freely select the most appropriate analysis mode on software according to sample characteristics and experimental purposes, and data quality compromise or failure generated when a single light path is used for a non-skilled experiment is avoided.

Description

Technical Field

[0001] This invention relates to the field of X-ray analysis instrument technology, specifically to a fully automatic switching X-ray diffractometer with dual light sources and front-to-back symmetry. Background Technology

[0002] X-ray diffraction (XRD) is an indispensable analytical technique in materials science, physics, chemistry, geology, and other fields. Currently, most commercial and laboratory X-ray diffractometers adopt a single-source design. However, in scientific research and production practice, researchers often need to use X-ray sources with different target materials (i.e., different wavelengths) according to different sample characteristics and experimental objectives.

[0003] For example, in experiments requiring micro-area or transmission mode analysis (thin film, capillary samples, etc.), short-wavelength molybdenum (Mo-Kα) or silver (Ag-Kα) X-ray sources are typically chosen, along with precision optical components such as multilayer focusing lenses or collimators, to obtain high-intensity, high-collimation X-ray beams. For routine powder sample phase analysis, copper (Cu-Kα) X-ray sources with moderate penetration and high diffraction angular resolution are commonly used, employing the classic Bragg-Brentano (BB) diffraction geometry.

[0004] In the prior art, CN104597065A discloses an X-ray diffractometer that can measure diffraction patterns using a conventional metal target X-ray tube with a reflection diffraction optical path, or it can measure diffraction patterns using a heavy metal target X-ray tube with a transmission or reflection diffraction optical path.

[0005] However, in existing technologies, switching between different light sources and optical path systems on a single diffractometer typically faces the following problems: First, changing the light source and optical path system is cumbersome. Replacing the X-ray tube, adjusting optical components (such as the Sola slit and focusing lens), and recalibrating the optical path are very time-consuming and technically demanding processes, usually taking several hours or even days, severely impacting experimental efficiency. Second, purchasing two independent diffractometers is costly. Purchasing two complete diffractometers for different experimental purposes, while solving the problem, occupies a large amount of laboratory space, and the purchase and maintenance costs of the instruments (especially the goniometer and detector) are very high, resulting in a waste of resources.

[0006] Meanwhile, in existing multifunctional diffractometer designs, the optical system usually shares the same spatial area, requiring complex mechanical adjustments during switching, which increases the difficulty of operation and the risk of system failure.

[0007] Therefore, there is an urgent need in this field for a diffractometer that can integrate two commonly used light sources and corresponding optical paths on a single instrument and achieve rapid, automatic, and interference-free switching, so as to improve equipment utilization, reduce overall costs, and enhance the convenience of experimental work.

[0008] In particular, there is a need for a dual-light source system that utilizes the inherent structural features of the goniometer to achieve a symmetrical front-to-back layout, so that the two optical path systems are completely separated in physical space and do not interfere with each other, while also enabling fully automatic switching. Summary of the Invention

[0009] To address the shortcomings of existing technologies, this invention provides a fully automatic switching X-ray diffractometer with dual light sources that is symmetrical front and rear, thus solving the problems mentioned in the background art.

[0010] To achieve the above objectives, the present invention provides the following technical solution:

[0011] A fully automatic X-ray diffractometer with dual light sources and front-rear symmetry includes a goniometer main unit with a vertical symmetrical structure, having a front conventional operating space and a rear symmetrical space; a first diffraction optical path system installed in the front conventional operating space, including a first light source arm with a first X-ray source and a first detector arm with a first detector; a second diffraction optical path system installed in the rear symmetrical space, including a second light source arm with a second X-ray source and a second detector arm with a second detector; and an integrated control system electrically connected to the goniometer main unit, the first diffraction optical path system, and the second diffraction optical path system; wherein the first diffraction optical path system and the second diffraction optical path system are connected... The optical path systems are completely separated in physical space and mechanical structure to ensure that the moving parts of the two systems do not interfere with each other within the full-angle scanning range. The integrated control system is used to perform adaptive switching control, and the specific steps include: responding to the user's mode selection command, loading the corresponding parameter set and completing the initialization and self-test of the specified optical path system; controlling the selected optical path system to perform optimized alignment of the beam and the sample and locking the diffraction geometry; driving the goniometer host and the activated detector to perform data acquisition and quality monitoring according to preset logic; and, upon receiving a switching command, safely shutting down the current optical path system, automatically completing the transfer of control to the other optical path system, hardware startup and status verification, and realizing fully automatic mode switching.

[0012] This invention provides a fully automated, dual-source X-ray diffractometer with front-to-back symmetry. Compared with existing technologies, it has the following advantages:

[0013] To address the issue that existing single-source diffractometers require manual replacement of the light source, reassembly of optical components, and time-consuming recalibration of the optical path when conducting different experiments, this invention utilizes the inherent θ / θ or θ / 2θ symmetry structure of a high-precision vertical goniometer host to integrate a first diffraction optical path system (such as a transmission mode with a short-wavelength Mo target) in the front conventional operating space and a second diffraction optical path system (such as a Bragg-Brentano reflection mode with a Cu target) in the rear symmetry space originally used for counterweights. A unified driving and management system is then implemented, significantly improving experimental efficiency and ease of use.

[0014] To address the limitations of traditional single-source diffractometers in terms of functionality and flexibility in handling diverse analytical needs, such as micro-area / transmission samples like thin films and capillaries, as well as conventional powder samples, this invention employs a first (pre-processor) system specifically optimized for micro-area or transmission analysis (e.g., thin film and capillary samples) requiring short-wavelength, highly collimated beams. A second (post-processor) system is specifically optimized for rapid phase analysis of conventional powder samples. This allows users to freely select the most suitable analysis mode in the software based on sample characteristics and experimental objectives, avoiding data quality compromises or failures that occur when using a single optical path for experiments outside their expertise. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This invention illustrates the automatic switching timing of X-ray diffraction modes. Figure 1 ;

[0017] Figure 2 This invention illustrates the automatic switching timing of X-ray diffraction modes. Figure 2 ;

[0018] Figure 3 This invention illustrates the experimental timing diagram for switching X-ray diffraction modes.

[0019] Figure 4 A top view schematic diagram of the overall structure proposed in this invention is shown.

[0020] As shown in the figure:

[0021] 1-Goniometer main unit; 2-First X-ray source; 3-First optical device; 4-First detector arm; 5-First detector; 6-Second X-ray source; 7-Second optical device; 8-Second detector arm; 9-Second detector; 10-Counterweight module. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] To understand the technical principle of this invention: Because most mainstream X-ray diffractometers currently employ a single light source and optical path design, they have significant limitations when dealing with diverse sample types and detection requirements. For example, when analyzing micro-area or transmission samples such as thin films and capillaries, a short-wavelength molybdenum (Mo) target light source with a focusing or parallel optical path is often required; while for routine powder phase analysis, a copper (Cu) target light source with Bragg-Brentano reflection geometry is more suitable. This means that if users need to perform both types of experiments on the same equipment, they can only do so through time-consuming and technically demanding manual replacement of the light source, reassembly, and recalibration of the optical path, or by purchasing two separate diffractometers, resulting in low efficiency, high cost, and space consumption.

[0024] Based on this, the present invention proposes a fully automatic switching X-ray diffractometer with dual light sources and front-rear symmetry. The aim is to integrate a first diffraction optical path system in the front operating space of the goniometer main unit 1, utilizing its inherent θ / θ or θ / 2θ symmetry structure, and a second diffraction optical path system in the rear symmetrical space (traditionally used for mounting counterweights). Furthermore, the two optical path systems are designed to be uniformly driven by an integrated control system, enabling rapid and automatic switching between two diffraction experimental modes.

[0025] As one embodiment of the present invention, such as Figures 1-4 As shown, the provided dual-source fully automatic switching X-ray diffractometer includes: a goniometer host 1, a first diffraction optical path system and a second diffraction optical path system, an integrated control system, a counterweight module 10, and a detector assembly.

[0026] In this embodiment, it should be noted that the proposed goniometer host 1, as the core support and motion platform of the entire system, adopts a vertical θ / θ or θ / 2θ structure. In specific implementation:

[0027] The goniometer main unit 1 includes a main unit base, a central rotating spindle, and a sample stage. The main unit base is fixed to the instrument base to provide a stable mounting foundation. The central rotating spindle vertically penetrates the goniometer main unit 1 and has an interface for mounting the sample stage. Around this central rotating spindle, two independent rotating axis systems are symmetrically arranged on the front and rear sides to support the light source arms and detector arms of the first and second diffraction optical path systems, respectively. Specifically: the front rotating axis system is located on the side of the main unit facing the operator; the rear rotating axis system is located on the side of the main unit facing away from the operator (traditional counterweight position).

[0028] Furthermore, the goniometer host 1 integrates a high-precision angle encoder and a servo drive motor. The servo drive motor is connected to the rotating shaft through a transmission mechanism. The high-precision angle encoder installed on it precisely controls the θ and 2θ angle movements of the light source arm and the detector arm to ensure scanning positioning accuracy and repeatability.

[0029] In this embodiment, the first diffraction optical path system is installed at the front operating position of the goniometer host 1. It is understood that its purpose is to perform transmission mode diffraction experiments based on short-wavelength X-rays (such as a molybdenum target), analyze samples such as thin films and capillaries that have high requirements for beam collimation and penetration, and achieve efficient micro-area or transmission diffraction data acquisition.

[0030] In specific implementation: the first diffraction optical path system includes a first light source arm, a first X-ray source 2, a first optical device 3, a first detector arm 4, and a first detector 5.

[0031] The first light source arm is mounted on the rotating shaft system on the front side of the goniometer main unit 1; the first X-ray source 2 is mounted at the end of the first light source arm. The light source is preferably a molybdenum target (Mo-Kα) or silver target (Ag-Kα) X-ray source with a shorter wavelength. Its built-in high-voltage cable and cooling pipe are connected to the external power supply and cooling system.

[0032] Furthermore, a first optical device 3 is installed in front of the light source outlet. It is preferably an optical element composed of a multilayer film focusing lens and a collimator. It can be understood that in actual applications, the first optical device 3 is rigidly connected to the first light source arm through a special clamp to form a collimated high-throughput incident beam, which shapes the X-rays into a high-intensity, high-collimation parallel beam in the output optical path of the first X-ray source 2.

[0033] Furthermore, the first detector arm 4 is mounted on another rotational axis system on the front side of the goniometer host 1 and corresponding to the first light source arm; a first detector 5 is mounted at the end of the first detector arm 4. This detector can be a two-dimensional hybrid pixel detector, and its data line and power line are routed along the arm body and converged to the host interface. The first light source arm and the first detector arm 4 of the first diffraction optical path system are driven by the goniometer host 1, and their rotation axes intersect at the sample position, forming a specific diffraction geometry (such as a transmission mode), realizing precise relative angular movement.

[0034] In this embodiment, the second diffraction optical path system is installed symmetrically at the rear of the goniometer host 1. It is understood that its purpose is to perform reflection mode diffraction experiments based on medium- and long-wavelength X-rays (such as copper targets) to analyze the rapid phases of conventional powder samples, and its optical path configuration is the classic Bragg-Brentano (BB) diffraction geometry.

[0035] In specific implementation, the second diffraction optical path system includes a second light source arm, a second X-ray source 6, a second optical device 7, a second detector arm 8, a second detector 9, and an integrated counterweight module 10.

[0036] The second light source arm and the second detector arm 8 are mirror images of the first diffraction optical path system. The second light source arm is mounted on the rotation axis at the rear of the goniometer main unit 1; the second X-ray source 6 is mounted at the end of the second light source arm. The light source is preferably a copper target (Cu-Kα) X-ray source with moderate penetration capability and high diffraction angle resolution, and its supporting pipeline is also connected to the external system.

[0037] Furthermore, a second optical device 7 is installed in front of the light source outlet. The second optical device 7 consists of a variable slit and a Sola slit. The second optical device is directly mounted on the extension support of the second light source arm and is used to form and optimize the beam conditions required for the Bragg-Brentano diffraction geometry.

[0038] Furthermore, the second detector arm 8 is mounted on the rear side of the goniometer main unit 1 on a rotating shaft corresponding to the second light source arm. A second detector 9 is mounted at the end of the second detector arm 8. It should be noted that the second detector 9 is a one-dimensional high-speed detector, used to ensure that the motion trajectories of the two sets of moving arms are completely separated within a 360-degree rotation range, without any spatial interference.

[0039] Furthermore, the counterweight module 10 is integrated within the structural frame of the second light source arm and / or the second detector arm 8, or is suspended in a modular form on the rear extension bracket of the connecting pivot of the two arms. It is understood that in practical applications, the position and mass of the counterweight can be finely adjusted according to the total weight and moment of inertia of the first diffraction optical path system, and fixed by locking screws. This balances the center of gravity shift caused by the loads on both sides, ensuring the dynamic stability and static torque balance of the goniometer during rotation, thereby guaranteeing the accuracy of angle measurement.

[0040] Based on the above technical concept, it should be noted that the second diffraction optical path system is connected to the goniometer host 1 through an independent mechanical structure to ensure that it is completely separated from the first diffraction optical path system in the motion space and does not interfere with each other.

[0041] In this embodiment, an integrated control system is used for the operation and switching of the entire instrument. It includes a main control unit, a motion control unit, a high-voltage power supply switching unit, a detector signal acquisition unit, and control software running on the main control unit.

[0042] In practical implementation, the main control unit is connected to the drive motor and encoder of the goniometer host 1 via a motion control card, to the first and second X-ray sources via a high-voltage power switching unit, and to the first and second detectors via a data acquisition card, thus forming a centralized control network. The following actions are then executed through the control software:

[0043] Based on the user-selected experimental mode (such as "front-mounted Mo target transmission mode" or "rear-mounted Cu target BB mode"), a command is sent to the high-voltage power supply switching unit to automatically shut down the non-use X-ray source and activate the target light source:

[0044] When the user selects the "Front Mo Target Transmission Mode", the control system turns on the power supply of the Mo target in the first light source arm, activates the first detector 5, and controls the movement of the goniometer and sample stage according to the motion logic of the transmission geometry.

[0045] When the user selects "Cu target BB mode", the system automatically shuts off the power supply of the front system, turns on the power supply of the Cu target in the second light source arm, activates the second detector 9, and scans according to the motion logic of BB geometry.

[0046] Meanwhile, by calling the motion logic and parameters of the goniometer that are perfectly matched to the selected mode through the motion control unit, and controlling the corresponding detector to start data acquisition, the automatic switching and operation between the two diffraction optical paths is realized.

[0047] In one embodiment of the present invention, the detector assembly is used to realize dual-optical-path signal acquisition. It should be noted that the detector assembly is preferably provided with the following two configuration schemes to meet the performance and budget requirements of different users. In specific implementation:

[0048] High-performance dual-detector solution: The detector assembly includes a permanently installed first detector 5 and a second detector 9. The first detector 5 is fixedly mounted at the end of the first detector arm 4, and the second detector 9 is fixedly mounted at the end of the second detector arm 8. The two detectors are connected to an integrated control system via cables. When switching experimental modes, the control system automatically activates the detector corresponding to the selected optical path and disconnects the power and signal link of the other detector, achieving a completely manual switching process.

[0049] Single-detector economical solution: The detector assembly consists of only one universal detector. To support rapid repositioning, identical quick-release interfaces are machined at the ends of both the first detector arm 4 and the second detector arm 8. This interface comprises a dovetail groove and a manual locking handle. The dovetail groove is installed on the mounting plane at the ends of the first detector arm 4 and the second detector arm 8, with its groove direction aligned with the detector insertion or removal direction, serving as a guiding and positioning mechanism. The locking handle is installed on the arm body corresponding to the dovetail groove via a threaded or swivel connection, with its internal locking component located above or to the side of the dovetail groove. Understandably, when the user operates manually: loosening the locking handle on the current arm allows the detector to slide out of the dovetail groove, then slide it into the dovetail groove of the other arm and re-lock it. Simultaneously, the interface integrates electrical contacts for transmitting power and control signals. Once the detector is in place, the control system identifies its position through the contacts, or the user can easily confirm it via the software interface. Subsequently, the system automatically completes the subsequent light source switching and movement.

[0050] As a second aspect of the present invention, an adaptive switching control method for a dual-source fully automatic switching X-ray diffractometer is proposed, the specific implementation steps of which include:

[0051] S1. System initialization and self-test execution to enter the workflow. When the user selects an experimental mode (e.g., "Front-mounted Mo target transmission mode") in the control software interface, the main control unit (MCU) responds immediately. Specific operations are as follows:

[0052] S1-1. Based on the system, parse the unique configuration identifier corresponding to this experimental mode and load the complete experimental parameter package from the preset parameter library. Its mathematical expression is:

[0053]

[0054] In the formula, The characteristic wavelength of X-rays and These represent the operating voltage and current of the X-ray tube, respectively. Used to define the start angle, end angle, and step size of the scan. For the detector integration time, This represents a specific set of diffraction geometry parameters, such as the sample-detector distance in transmission mode. , This is a set of calibration coefficients, such as a detector pixel sensitivity correction map.

[0055] S1-2. Initialization commands are broadcast to each subsystem via the internal bus, and a self-test process is initiated. In practice, after receiving the commands, the motion control unit reads the absolute position value of the high-precision rotary encoder connected to it. and the mechanical zero point stored in non-volatile memory. If a deviation exists during the comparison... ,and Zero-point tolerance, usually The controller will drive the motor micro-motion through the motor driver, and its control law adopts an incremental PID algorithm:

[0056]

[0057] In the formula, , where is the angle deviation of the k-th sampling. The parameters were calibrated to suit the low-speed, high-precision characteristics of the goniometer. This is the increment of the control input sent to the driver. Understandably, this process converges rapidly until... After completing the zeroing and calibration of the motion axis, the motion control unit sends a motion system readiness signal back to the host computer. .

[0058] S1-3. While the motion system is performing a self-test, control the high-voltage power supply switching unit to operate synchronously: [The received signal will be transferred to the next device]. In Parameters are sent to the setting channels of two independent high-voltage generators. Depending on the mode selection, only the target generator (such as high-voltage generator a corresponding to the Mo target) is enabled. At this time, the generator executes a soft-start program to set its output voltage. and pipe flow The pressure increases exponentially to prevent electrical shock to the X-ray tube.

[0059]

[0060] In the formula, and As a time constant, the unit monitors and responds in real time during the output setup process. and ,make sure Simultaneously, the X-ray tube cooling circuit is activated, and the coolant flow rate is monitored. and temperature Once the high voltage is stable, cooling is normal, and the shutter and signal feedback are in the "off" state, the high voltage power supply switching unit will send a "high voltage system ready" signal. It should be noted that high-voltage generator b is completely de-energized and isolated to ensure absolute safety.

[0061] S1-4. Initialize the detector controller: In specific implementation, load... Parameters related to the detector (such as operating mode, gain, etc.) The controller automatically performs one round of noise acquisition on the designated detector (first X-ray source): with the X-ray shutter closed, N frames are acquired. The data is used to calculate the average background count and standard deviation for each pixel or channel and store it as a background template. Subsequently, the controller checks the detector's data link, performs a high-speed dummy data loopback test to verify communication integrity, and then sends a detector system readiness signal back. .

[0062] Obtain the ready signals of all subsystems and safety interlock status (sample chamber door closed, radiation protection, etc.), if and only if When all values ​​are 1 and all security conditions are met, the software interface displays "System initialization complete, ready," forming reliable startup data.

[0063] S2. Beam path optimization and diffraction geometry locking. It can be understood that the purpose of this step is to establish and lock the precise spatial relationship that conforms to the selected diffraction theory model, that is, to ensure that the X-ray beam, the sample test point and the detector receiving surface follow the preset transmission geometry or Bragg-Brentano geometry.

[0064] In specific implementation, S2-1, after the system is ready, the control flow enters the geometric alignment stage, which is crucial for ensuring the quality of experimental data. The control unit issues a "start alignment" command, and the motion control unit drives the relevant motion axes to the alignment start position according to the geometric constraints in the parameter set G. For example, in transmission mode, the first light source arm and the first X-ray source are driven to be roughly symmetrically positioned on both sides of the sample; in BB mode, the second light source arm and the second detector arm are driven to initially satisfy the focusing circle relationship between the light source focal spot, the sample surface, and the receiving slit.

[0065] S2-2. Perform active optimization and calibration of the beam path. First, place a standard calibration sample (such as a silicon powder standard sheet) with known diffraction characteristics at the sample location. The motion control unit controls the detector arm (such as the first X-ray source) within a small angular range where strong diffraction peaks are expected to appear, such as... Continuous scanning is performed inside; the detector controller synchronously acquires diffraction intensity signals. And transmit it back in real time.

[0066] right Real-time analysis was performed to locate the measured diffraction peak positions. Based on Bragg's law, the theoretical peak position was calculated. Meanwhile, the system calculates the peak position deviation. This indicates that the beam path is not perfectly aligned. As input, the required minute angular or linear adjustments to the light source arm or detector arm are derived from a pre-calibrated error compensation model. .

[0067] In this embodiment, the error compensation model can be simplified to a linear transformation:

[0068]

[0069] In the formula, j is the Jacobian matrix used to describe the relationship between system geometric error and peak position shift, obtained through factory calibration. The motion control unit receives... The closed-loop control unit drives the corresponding motor to perform this fine-tuning. After adjustment, the system performs a rapid scan again to verify the new... Understandably, this iterative process continues until... When the convergence threshold is less than the preset threshold, the beam path is optimized to its optimal state. Simultaneously, the system continues to optimize parameters such as the Solar slit angle and the receiving slit width to maximize the signal-to-noise ratio of the diffraction peak. .

[0070] S2-3. After beam optimization, perform automatic sample centering. It should be noted that the sample must be located on the rotation center axis of the goniometer. In practice:

[0071] Image plane coordinates of sample feature points (such as the surface of powder samples and the center of capillaries) are extracted using image processing algorithms. And the projection of the laser crosshair center, i.e., the mechanical rotation center, onto the image plane. Compare and obtain the offset. Subsequently, based on the camera calibration matrix (Pre-calibrated using a standard grid plate), the image plane offset is converted into a true spatial offset command for the sample stage. .

[0072] Simultaneously, the motion control unit receives this command and controls the XYZ translation motors of the sample stage to perform displacement in a closed-loop manner. After the displacement is completed, the system captures another image and calculates the new offset. It should be noted that this cycle requires 2-3 iterations to position the sample center relative to the rotation axis. Within this range, record the coordinates of the sample stage at this moment as the "center position" of this experiment. .

[0073] S2-4. After completing all alignments, determine the optimal position of all current motion axes (light source arm angle). Detector arm angle Sample stage position Optical device settings (slit width, focusing lens tilt angle) and precise instrument width parameters extracted from the diffraction spectrum of the standard sample. Wait, package as calibrated geometry The data is then stored in the process file for this experiment. Simultaneously, the X-ray shutter is closed, preparing for the formal data acquisition phase.

[0074] S3. Data collection and online quality monitoring.

[0075] S3-1. After the user confirms and starts the formal scan, according to the parameter set... Generate discrete angle point sequences .Will The target value is sent to the motion control unit. The motion control unit then adjusts the value based on the current angle. and target A smooth motion trajectory is planned, including acceleration, constant speed, and deceleration phases, to prevent vibration and overshoot. The trajectory planning employs an S-curve algorithm to ensure continuous acceleration variation. The motor driver drives the motor according to the commands generated by this trajectory, and a high-precision rotary encoder provides real-time position feedback. When the system determines that it has entered the positioning range and the angular velocity meets the preset angle, the motion control unit simultaneously sends a high-precision "position in place" trigger signal to the main control unit and the detector controller. .

[0076] S3-2, The detector controller receives... At the instant of the signal, the detector's integration period is initiated: within the preset integration time, the detector counts the incident X-ray photons, and during the integration period, all motion axes are kept absolutely stationary. After the integration is completed, the controller initiates the readout sequence.

[0077] In specific implementation, for a one-dimensional detector, the readout is a series of channel count values; for a two-dimensional detector, the readout is a single image. The pixel intensity matrix.

[0078] Furthermore, during the readout process, the controller performs online preprocessing in parallel, including flat field correction and outlier filtering to remove spike signals caused by cosmic rays. Finally, the processed data is transmitted in real time to the memory buffer of the main control unit via a high-speed data bus.

[0079] S3-3. While receiving data, the main control unit runs a lightweight real-time analysis thread: In specific implementation, it calculates the key quality indicators of each frame of data in real time, including the total count rate, the signal-to-noise ratio of the expected diffraction peak region, and the correlation with the previous frame of data, and compares them with preset thresholds: If the total count rate is abnormally low, the scanning is immediately paused and an alarm is issued; if the count rate fluctuates within the preset range, the subsequent integration time is dynamically adjusted based on the expected count rate to maintain the consistency of the counting statistics.

[0080] Meanwhile, the high-voltage power supply unit continuously monitors the actual power of the X-ray tube to ensure that its fluctuation range is within the preset range. After the entire scanning sequence is completed, all data in the buffer is integrated into the final diffraction pattern, and a final state quality assessment is performed. Finally, the system status is updated to "Data acquisition complete," the pattern is saved, and the user is prompted to perform the next operation or switch modes.

[0081] S4. Implement automatic switching. It should be noted that, firstly, the purpose of this step is to safely exit the current experimental mode, completely switch to another mode, and verify the readiness status of the new mode.

[0082] In practice, when the user selects to switch to another mode on the control software (such as switching from "front Mo target transmission mode" to "rear Cu target BB mode"), in order to ensure safety and equipment lifespan, the system performs a soft shutdown of the current operating mode: the main control unit instructs the high-voltage power supply unit to make the X-ray tube current slope down to zero according to an exponential law and then cut off the high voltage, and simultaneously close the X-ray shutter.

[0083] Secondly, the motion control unit drives all robotic arms to a pre-calibrated "safe parking position"; then the control unit logic switches to the rear optical path and immediately performs a rapid self-test and zeroing of the motors and encoders of the rear system; at the same time, the detector controller completes the detector switching according to the preset scheme: in the dual detector configuration, the front detector is turned off and the rear detector is activated; in the single detector configuration, it is automatically identified through the electrical interface or re-initialized after waiting for user confirmation.

[0084] Next, based on the parameters of the new mode loaded by the main control unit, the high-voltage power supply unit is turned on and preheats the new X-ray tube, and the motion unit positions the rear light source arm and detector arm to the preparatory position of the new geometry; then, an ultra-fast verification scan is performed using the installed built-in reference sample (such as a silicon wafer).

[0085] Finally, the diffraction peak positions obtained from the verification scan are analyzed, their deviations from the theoretical values ​​are calculated, and a three-level judgment is made based on the preset tolerance: if the deviation is extremely small, the switch is directly judged as successful; if the deviation is slight, software compensation is automatically injected for calibration; if the deviation exceeds the limit, an alarm is triggered and a check is prompted. After successful verification, the system interface and status are completely updated to the new mode, ready to start loading new samples and conducting experiments.

[0086] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A front-back symmetrical double light source full-automatic switching X-ray diffractometer, characterized in that, include: The main unit of the goniometer adopts a vertical symmetrical structure, with a front conventional operation space and a rear symmetrical space on it; The first diffraction optical path system is installed in the front conventional operating space and includes a first source arm with a first X-ray source and a first detector arm with a first detector; the second diffraction optical path system is installed in the rear symmetrical space and includes a second source arm with a second X-ray source and a second detector arm with a second detector; the integrated control system is electrically connected to the goniometer host, the first diffraction optical path system and the second diffraction optical path system; The first diffraction optical path system and the second diffraction optical path system are completely separated in physical space and mechanical structure to ensure that the moving parts of the two systems do not interfere with each other in the full-angle scanning range; The integrated control system is used to perform adaptive switching control, and the specific steps include: In response to user mode selection commands, the system loads the corresponding parameter set and completes the initialization and self-test of the specified optical path system; it controls the selected optical path system to perform optimized alignment of the beam and sample and lock the diffraction geometry; it drives the goniometer host and the activated detector to perform data acquisition and quality monitoring according to preset logic; and when a switching command is received, it safely shuts down the current optical path system, automatically completes the transfer of control to another optical path system, hardware startup and status verification, and realizes fully automatic mode switching.

2. The fully automatic switching X-ray diffractometer with front and rear symmetrical dual light sources according to claim 1, characterized in that: In the adaptive switching control step executed by the integrated control system, the state verification step includes: controlling the newly activated optical path system to perform a rapid verification scan on a built-in reference sample, and automatically determining the switching success, performing software compensation calibration, or triggering an alarm by analyzing the deviation between the measured diffraction peak position and the theoretical value.

3. The fully automatic switching X-ray diffractometer with front and rear symmetrical dual light sources according to claim 2, characterized in that: The integrated control system includes a main control unit, a motion control unit, a high-voltage power supply switching unit, and a detector signal acquisition unit; The main control unit is connected to the motion control unit, the high-voltage power switching unit, and the detector signal acquisition unit via an internal bus interface, and is used to execute command issuance and status data collection. The motion control unit is connected to the servo drive motor and high-precision angle encoder in the goniometer host via a multi-axis motion control card and drive cable. The high-voltage power switching unit is connected to the power supply and shutter drive circuit of the first X-ray source and the second X-ray source via a high-voltage cable and interlock control line, respectively. The detector signal acquisition unit is connected to the first detector and the second detector via a high-speed data cable and a power control line.

4. The fully automatic switching X-ray diffractometer with front and rear symmetrical dual light sources according to claim 1, characterized in that: The first detector and the second detector are two independent detectors, which are used to adapt their corresponding light paths, and are respectively fixedly installed at the ends of the first detector arm and the second detector arm. Through the integrated control system, the working states of the first detector and the second detector are automatically switched according to mode selection. 5.The front-back symmetrical double light source full-automatic switching X-ray diffractometer according to claim 1 or 2, characterized in that: The ends of the first detector arm and the second detector arm are provided with structure-same quick dismounting interfaces. When only one general detector is installed on the diffractometer, the general detector is manually exchanged and installed on any detector arm through the quick dismounting interfaces, and is electrically connected with the integrated control system to identify the detector position and complete corresponding configuration loading. 6.The front-back symmetrical double light source full-automatic switching X-ray diffractometer according to claim 5, characterized in that: The quick dismounting interface includes a dovetail groove and a locking handle, and an electrical contact is integrally installed in the quick dismounting interface, which is used to automatically establish the connection of power supply, control and data signal after the detector is installed in place; The dovetail groove is installed on the mounting plane at the end of the first detector arm and the second detector arm, and the groove direction is consistent with the insertion or extraction direction of the detector, so as to serve as a guide and positioning mechanism. The locking handle is installed on the arm body corresponding to the side of the dovetail groove through threaded connection or pivot connection, and the locking part integrally installed in the locking handle is located above or beside the dovetail groove. 7.The front-back symmetrical double light source full-automatic switching X-ray diffractometer according to claim 1, characterized in that: The goniometer main machine includes a main machine base, a center rotating main shaft, a sample table and two sets of independent rotating shaft systems symmetrically arranged on the front side and the rear side. The main machine base is located at the bottom of the whole main machine, and is horizontally installed and fixed on the instrument base. The center rotating main shaft penetrates through and is installed at the center position of the main machine base vertically. The sample table is directly installed at the top end of the center rotating main shaft. The two sets of independent rotating shaft systems are arranged on the two sides of the center rotating main shaft in a front-back mirror image symmetrical manner. The first light source arm and the first detector arm are installed on the front rotating shaft system, and the second light source arm and the second detector arm are installed on the rear rotating shaft system. 8.The front-back symmetrical double light source full-automatic switching X-ray diffractometer according to claim 1, characterized in that: The first X-ray source is a molybdenum target or silver target tube with shorter wavelength, and its light path follows the transmission type diffraction geometry. The second X-ray source is a copper target tube, and its light path follows the Bragg-Brentano reflection type diffraction geometry. 9.The front-back symmetrical double light source full-automatic switching X-ray diffractometer according to claim 1, characterized in that: A counterweight module is integrally installed in the second diffraction light path system, which is used to balance the gravity center deviation caused by the load of the first diffraction light path system, so as to ensure the motion accuracy and dynamic stability of the goniometer main machine.

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