CN112260057A - Calcium atomic beam optical frequency scale detection light automatic locking method - Google Patents
Calcium atomic beam optical frequency scale detection light automatic locking method Download PDFInfo
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Abstract
The invention discloses a calcium atomic beam optical frequency scale detection light automatic locking method, which solves the problem that the existing method cannot automatically re-lock after losing lock. The method comprises the following steps: the coarse scan determines a first bias voltage and a first current: scanning in a set voltage scanning range and a set current scanning range, collecting the amplitude of a front window fluorescence signal, and determining a first bias voltage and a first current; fine scan determines lock point: adjusting the current of a laser tube to be a first current, adjusting the external cavity PZT voltage of the laser to scan according to a second voltage step between a first bias voltage and a first peak voltage, taking a sampling point corresponding to a reference fluorescence signal peak value of a rear window as a locking point of a fluorescence signal of a front window, and recording the external cavity PZT voltage of the laser corresponding to the locking point as a second bias voltage; and adjusting the current of the laser tube to be a first current, adjusting the external cavity PZT voltage of the laser to be a second bias voltage, and realizing automatic frequency locking by adopting a PID (proportion integration differentiation) technology. The invention can realize the relocking after losing the lock.
Description
Technical Field
The invention relates to the field of laser frequency stabilization, in particular to an automatic locking method for calcium atomic beam optical frequency scale detection light.
Background
In the calcium atom beam optical frequency scale detection experiment, 423nm laser and calcium atom beam interaction is adopted to detect fluorescence spectrum lines, and the frequency of the 423nm laser needs to be locked so as to be stabilized at the 423nm transition center of calcium atoms. The continuous locking time of the system determines the stability of the system, but in experiments, the system is easily affected by factors such as light blocking, environmental vibration, audio vibration, air pressure change and the like to cause the unlocking phenomenon. Due to the lack of a monitoring mechanism, the laser works in an abnormal mode after losing lock, and the laser current and the PZT voltage both deviate from the normal working state greatly. After the locking is released, the working state of the laser drifts freely and cannot be stabilized. Therefore, the system recovery time is long, stable fluorescence spectral lines cannot be found within about 15 minutes, technicians are required to manually dial and turn the laser controller, and manual locking is performed after the spectral lines are found back, so that the system needs to be kept on duty when continuously running, and much inconvenience is brought to the experiment.
Disclosure of Invention
The invention provides a calcium atomic beam optical frequency scale detection light automatic locking method, which solves the problem that the existing method cannot automatically re-lock after losing lock.
In order to solve the problems, the invention is realized as follows:
the invention discloses a calcium atomic beam optical frequency scale detection light automatic locking method, which comprises the following steps: the coarse scan determines a first bias voltage and a first current: in a set voltage scanning range and a set current scanning range, adjusting the external cavity PZT voltage of the laser and the current of the laser tube according to a first voltage step and a first current step to scan, and simultaneously acquiring and recording the amplitude of a front window fluorescence signal, if a current sampling point meets the condition that a sampling value is greater than or equal to a first threshold value, and the absolute value of the difference between the sampling value and a sampling value of an adjacent sampling point is smaller than a second threshold value, determining the external cavity PZT voltage of the laser corresponding to the sampling point as the first bias voltage, the current of the corresponding laser tube as the first current, and the voltage corresponding to the amplitude peak value of the front window fluorescence signal in the scanning process as a first peak voltage; fine scan determines lock point: adjusting the current of a laser tube to be the first current, adjusting the external cavity PZT voltage of the laser to scan according to the step of a second voltage between the first bias voltage and the first peak voltage, taking a sampling point corresponding to the peak value of the rear window reference fluorescence signal as a locking point of the front window fluorescence signal, and recording the external cavity PZT voltage of the laser corresponding to the locking point as the second bias voltage; and adjusting the current of the laser tube to be the first current, adjusting the external cavity PZT voltage of the laser to be the second bias voltage, collecting the amplitude of the front window fluorescence signal and the amplitude of the rear window fluorescence reference signal in real time, taking the difference of the two as an error signal, and realizing automatic frequency locking by adopting a PID (proportion integration differentiation) technology.
Further, the method further comprises: adjusting the current of the laser tube to be the first current, adjusting the external cavity PZT voltage of the laser according to the third voltage step between the second peak voltage and the third bias voltage to scan, and simultaneously acquiring the amplitude of the front window fluorescence signal, and determining the acquisition point as a re-locking point when the absolute value of the difference between the voltage value corresponding to the amplitude of the front window fluorescence signal corresponding to the acquisition point and the external cavity PZT voltage of the laser is less than or equal to a fourth threshold value; and the second peak voltage is the voltage corresponding to the amplitude peak value of the front window fluorescence signal in a locked state, and the third bias voltage is the laser external cavity PZT voltage corresponding to the second peak voltage.
Preferably, the step of adjusting the external cavity PZT voltage of the laser and the laser tube current in the set voltage scanning range and current scanning range according to the first voltage step and the first current step further comprises: determining a voltage scan list as [ V ] according to the voltage scan range and the first voltage step1，V2，……，Va]Determining a current sweep list as [ I ] from the current sweep range and the first current step1，I2，……，In](ii) a Regulating laser tube current to I1Sequentially adjusting the external cavity PZT voltage of the laser to [ V ]1，V2，……，Va]Scanning, if the first bias voltage is not found, adjusting the current of the laser tube to be I2Continuing to scan until findingTo the first bias voltage or over all voltage and current values; wherein, V1，V2，……，VaFor the voltage sweep list, I1，I2，……，InThe list is scanned for the current.
Preferably, the first threshold is equal to or greater than 1V, and the second threshold is equal to or less than 0.03V.
Preferably, the second voltage step is smaller than the first voltage step.
Preferably, the voltage scanning range is 65V-70V, the first voltage scanning step is 0.1V, the current scanning range is 47.8-48.5 mA, and the first current step is 0.1 mA.
Preferably, the third threshold is equal to or less than 0.4V.
Preferably, the third bias voltage is greater than or equal to 80V, the fourth threshold is less than or equal to 0.01V, and the third voltage step is less than or equal to 0.001V.
The beneficial effects of the invention include: the invention provides a calcium atomic beam optical frequency scale detection light automatic locking method which can realize the functions of automatic fluorescence spectrum line scanning, automatic frequency locking, locking state monitoring and re-locking within 15 seconds after losing the lock under the condition that the working temperature of a laser is stable, thereby reducing the requirement on manual monitoring, avoiding excessive manual intervention in an experiment, having strong engineering applicability and being widely popularized.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 is a schematic diagram of a principle embodiment of an experimental embodiment of the method of the present invention;
FIG. 2 is a flow chart of an embodiment of a method for automatically locking a detection light of a calcium atomic beam optical frequency scale;
FIG. 3 is a flowchart of an embodiment of a method for automatically locking a probe light including a relocked calcium atom beam optical frequency scale;
FIG. 4 is a flow chart of an embodiment of a method for automatically locking a detection light of a calcium atomic beam optical frequency scale including state switching.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the specific embodiments of the present invention and the accompanying drawings. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The innovation points of the invention are as follows: firstly, the method adopts a secondary scanning determination method of coarse scanning and fine scanning when the calcium atomic beam optical standard detection optical system determines the locking point, so that the determined locking point is more accurate, and the laser frequency output by the laser can be quickly stabilized at 423 nm; secondly, the invention can enter a rescanning locking mode after the frequency is unlocked, so that the system automatically locks and outputs the laser signal with stable frequency without manual intervention, thereby reducing uncertainty.
The technical solutions provided by the embodiments of the present invention are described in detail below with reference to the accompanying drawings.
FIG. 1 is a schematic diagram of an experimental scheme of the method according to the present invention, illustrating the principle of automatic locking of the optical system of the calcium atomic beam frequency scale detection.
As the embodiment of the invention, the laser and the controller thereof contained in the calcium atomic beam frequency scale detection light system are external cavity semiconductor lasers, and the laser frequency can be adjusted by adjusting the external cavity PZT voltage of the laser, the current of a laser tube and the temperature of the laser tube.
As shown in fig. 1, an external cavity semiconductor laser generates a 423nm laser signal, the 423nm laser signal is divided into two beams of a beam and a beam B by a polarization beam splitter prism, wherein the beam a has a certain included angle with an atomic beam, the beam B is perpendicular to the atomic beam, a front window is formed in a region where the beam a intersects with the atomic beam, a rear window is formed in a region where the beam B intersects with the atomic beam, a signal formed by photoelectric conversion of the beam a after passing through the atomic beam is a front window fluorescence signal, and a signal formed by photoelectric conversion of the beam B after passing through the atomic beam is a rear window fluorescence reference signal.
The B beam light vertically incident on the rear window and the atomic beam current resonate to form a fluorescence spectrum line, meanwhile, the amplitude of a fluorescence signal of the front window is positioned in the center of the edge of the fluorescence spectrum line, the corresponding voltage of the center of the edge is a locking zero point, namely a locking point of the system, and the edge signal of the front window is used as an error signal of servo feedback of the calcium atomic beam frequency standard detection light system, so that the laser can be locked at the locking point of the fluorescence spectrum of the front window, and the laser wavelength of the calcium atomic beam frequency standard detection light system is stabilized at 423 nm.
Fig. 2 is a flow embodiment of a method for automatically locking a detection light of a calcium atom beam optical frequency scale, which can be used in a calcium atom beam optical frequency scale detection light system, wherein a laser and a controller of the system are external cavity semiconductor lasers, and as an embodiment of the invention, the method for automatically locking the detection light of the calcium atom beam optical frequency scale specifically comprises the following steps:
in step 101, a first bias voltage and a first current are determined by coarse scanning.
In step 101, in a set voltage scanning range and a set current scanning range, adjusting the external cavity PZT voltage of the laser and the current of the laser tube according to a first voltage step and a first current step to scan, and simultaneously acquiring and recording the amplitude of the front window fluorescent signal, if a current sampling point satisfies that a sampling value is greater than or equal to a first threshold value, and an absolute value of a sampling value difference between the current sampling point and an adjacent sampling point is smaller than a second threshold value, determining that the external cavity PZT voltage corresponding to the sampling point is the first bias voltage, the corresponding current of the laser tube is the first current, and the voltage corresponding to the amplitude peak value of the front window fluorescent signal in the scanning process is the first peak voltage.
In step 101, the voltage scanning range, the current scanning range, the first voltage step, and the first current step are all preset values, and the setting of the parameter values directly affects the scanning time, so that both the actual condition of the system and the scanning time need to be considered when the scanning range and the step are set, for example, in the embodiment of the present invention, the voltage scanning range is 65V to 70V, the first voltage scanning step is 0.1V, the current scanning range is 47.8 to 48.5mA, and the first current step is 0.1 mA.
It should be noted that the voltage scanning range and the current scanning range may be from small to large or from large to small or may be a preset random-arranged discrete sequence, which is not limited herein.
In step 101, the method further comprises:
step 101A, determining a voltage scan list as [ V ] according to the voltage scan range and the first voltage step1，V2，……，Va]Determining a current sweep list as [ I ] from the current sweep range and the first current step1，I2，……，In]。
In step 101A, V1，V2，……，VaFor the voltage sweep list, I1，I2，……，InThe list is scanned for the current.
Step 101B, adjusting the current of the laser tube to be I1Sequentially adjusting the external cavity PZT voltage of the laser to [ V ]1，V2，……，Va]Scanning, if the first bias voltage is not found, adjusting the current of the laser tube to be I2The scan continues until the first bias voltage is found or all voltage and current values are traversed.
In step 101B, if the first bias voltage is not found after traversing all the voltage values and the current values, the voltage scanning range and/or the current scanning range may be reset, and the scanning may be restarted.
In step 101, the judgment condition for finding the first bias voltage is: the current sampling point meets the condition that the sampling value is more than or equal to the first threshold, and the absolute value of the sampling value difference between the current sampling point and the adjacent sampling point is less than the second threshold.
It should be noted that, the adjacent sampling point may refer to a sampling point before the current sampling point or a sampling point after the current sampling point, that is, the absolute value of the difference between the sampling value of the current sampling point and the sampling value of the previous sampling point is smaller than the second threshold, or the absolute value of the difference between the sampling value of the current sampling point and the sampling value of the next sampling point is smaller than the second threshold, or the absolute values of the differences between the sampling value of the current sampling point and the sampling values of the previous sampling point and the next sampling point are both smaller than the second threshold.
In the determination condition for finding the first bias voltage, the first threshold and the second threshold are both preset values, and may vary according to system parameters, in an embodiment of the present invention, the first threshold is greater than or equal to 1V, the second threshold is less than or equal to 0.03V, and the first threshold and the second threshold may also be other values, which is not particularly limited herein.
In step 101, if the sampling point meets the judgment condition for finding the first bias voltage, it is determined that the atomic spectral line is scanned, and therefore, the external cavity PZT voltage corresponding to the sampling point needs to be recorded as the first bias voltage, and the corresponding laser tube current is the first current.
It should be noted that, there is a corresponding relationship between the amplitude value of the front window fluorescence signal and the voltage value, generally, there is a proportional relationship between the amplitude value of the collected front window fluorescence signal and the voltage value, the proportionality coefficient may be 1 or other numerical values, if the proportionality coefficient is 1, it indicates that the amplitude value of the collected front window fluorescence signal is the voltage value of the front window fluorescence signal, and therefore, the corresponding voltage value is also the largest when the amplitude value of the front window fluorescence signal is the largest.
In step 102, the current of the laser tube is adjusted to be the first current, the external cavity PZT voltage of the laser is adjusted in a stepping manner according to the second voltage between the first bias voltage and the first peak voltage for scanning, the sampling point corresponding to the peak value of the rear window reference fluorescence signal is the locking point of the front window fluorescence signal, and the external cavity PZT voltage of the laser corresponding to the locking point is recorded as the second bias voltage.
In step 102, the laser tube current of the system is set to the first current, which is an automatic system setting process.
In step 102, if the maximum value of the voltage sweep range is VaThe first bias voltage is VmThen at VmAnd VaAccording to the second voltage step setting outside the laserAnd (5) the cavity PZT is electrified, and a fluorescence spectrum line scanning mode is started.
In step 102, the second voltage step is smaller than the first voltage step, so that fine scanning can be realized to make the found lock point more accurate, for example, the second voltage step is 0.001V, the first voltage step is 0.1V, and specific values of the first and second voltage steps are not particularly limited.
In step 102, when the fine scanning mode is started, the front window fluorescence spectrum line is adjusted to the center of the screen, after scanning is finished, the external cavity PZT voltage X corresponding to the rear window reference fluorescence signal peak value and corresponding to the laser external cavity PZT voltage X, that is, the second bias voltage and the sampling point amplitude Y of the front window fluorescence signal at the voltage are calculated, and (X, Y) is used as the front window signal locking point.
And 103, adjusting the current of the laser tube to be the first current, adjusting the external cavity PZT voltage of the laser to be the second bias voltage, collecting the amplitude of the front window fluorescence signal and the amplitude of the rear window fluorescence reference signal in real time, taking the difference between the two as an error signal, and realizing automatic frequency locking by adopting a PID (proportion integration differentiation) technology.
In step 103, the laser tube current is adjusted to the first current, and the external cavity PZT voltage of the laser is adjusted to the second bias voltage, which is an automatic adjustment process of the system.
In step 103, the laser tube current is adjusted to the first current, the laser external cavity PZT voltage is adjusted to the second bias voltage, then the scanning is turned off, the PID locking function is synchronously turned on, and the automatic locking is realized.
It should be noted that, starting the PID locking function to achieve automatic locking refers to acquiring the amplitude of the front window fluorescence signal and the amplitude of the rear window fluorescence reference signal in real time, taking the difference between the two as an error signal of system servo feedback, and achieving automatic locking through the self-closing loop adjustment of PID, where the wavelength of the laser output signal is stabilized at a target wavelength (e.g., 423 nm).
The embodiment of the invention provides a calcium atomic beam optical frequency scale detection light automatic locking method, which is used for scanning atomic fluorescence spectrum signals, finding a locking point and automatically locking. The principle of the method is as follows: after the system is started, the scanning-locking function of the laser frequency is automatically completed according to the electric parameter range set by a user, the manual adjustment by technicians is not needed, the system can be self-locked quickly, and the smooth experiment is ensured. The method has the advantages of reducing manual input, saving human resources, reducing human interference and avoiding frequency deviation every time when people are locked.
Fig. 3 is a flow embodiment of an automatic locking method for detecting light with a calcium atom beam optical frequency scale, which includes relocking, and provides a method for relocking after losing lock, as an embodiment of the present invention, an automatic locking method for detecting light with a calcium atom beam optical frequency scale, including the following steps:
in step 101, a first bias voltage and a first current are determined by coarse scanning.
And 103, adjusting the current of the laser tube to be the first current, adjusting the external cavity PZT voltage of the laser to be the second bias voltage, collecting the amplitude of the front window fluorescence signal and the amplitude of the rear window fluorescence reference signal in real time, taking the difference between the two as an error signal, and realizing automatic frequency locking by adopting a PID (proportion integration differentiation) technology.
And 104, if the amplitude of the collected front window fluorescence signal is less than or equal to a third threshold value, losing the frequency and entering a relocking mode.
In step 104, the current of the laser tube is adjusted to be the first current, the external cavity PZT voltage of the laser is adjusted in a stepping manner according to the third voltage between the second peak voltage and the third bias voltage to scan, the amplitude of the front window fluorescence signal is collected, and when the absolute value of the difference between the voltage value corresponding to the amplitude of the front window fluorescence signal corresponding to the collection point and the external cavity PZT voltage of the laser is less than or equal to the fourth threshold, the collection point is determined to be the relocking point.
The second peak voltage is the amplitude corresponding to the peak value of the front window fluorescence signal in the locked state, and the third bias voltage is the external cavity PZT voltage of the laser corresponding to the second peak voltage, that is, the external cavity PZT voltage of the laser corresponding to the peak value of the front window fluorescence signal.
In step 104, after locking, the system enters a monitoring state, and the currently locked signal amplitude is sampled and analyzed in real time, where the locked signal amplitude refers to the amplitude of the front window fluorescence signal, and if light blocking, environmental vibration, and other factors are encountered, the locking is lost, so that the atomic fluorescence spectral line signal amplitude is reduced to zero, the average value of the signals sampled by the system is lower than a third threshold value, and the system automatically exits the locking mode at this time.
In step 104, the system starts to monitor the locking signal in real time, and because the system detects a larger PZT voltage (e.g., 100V) when the lock is lost, the fluorescence spectrum disappears instantly, and the spectrum cannot be scanned for a long time, and the amplitude of the collected front window fluorescence signal is smaller than or equal to a third threshold.
In step 104, the spectral lines in the locked state are stored in a list form, and it is determined in real time whether the value is lower than a set threshold, that is, the amplitude of the front window fluorescence signal is collected in real time, and if the amplitude of the collected front window fluorescence signal is smaller than or equal to a third threshold, the system is in the unlocked state.
And when the system is in an unlocking state, the current of the laser tube is adjusted to be the first current, and the external cavity PZT voltage of the laser is adjusted in a stepping mode according to the third voltage between the second peak voltage and the third bias voltage to carry out fluorescence spectrum scanning.
In the embodiment of the invention, the third bias voltage is set to 80V, and the fluorescent spectrum signal can be rescanned in 15 seconds when the lock is lost. It should be noted that the third bias voltage is larger than the maximum value of the voltage sweep range, so that a larger voltage sweep range is obtained, which is beneficial to re-entering the locked state.
In the embodiment of the present invention, the third threshold is equal to or less than 0.4V, and a specific numerical value of the third threshold is not particularly limited.
In the embodiment of the present invention, the fourth threshold is equal to or less than 0.01V, and the third voltage step is equal to or less than 0.001V, and specific values of the fourth threshold and the third voltage step are not particularly limited.
It should be noted that, in the embodiment of the present invention, the third bias voltage is 80V, and the third voltage step is 0.001V, so that the system can achieve relocking within 15 s.
The calcium atomic beam optical frequency scale detection light automatic locking method provided by the embodiment of the invention has the functions of locking monitoring and automatic locking again after unlocking, for example, after the laser is unlocked due to factors such as light blocking, environmental vibration and the like, a technician is not required to manually adjust, the system can be quickly self-locked, the smooth experiment is ensured, the manual input can be reduced, the human resources are saved, the human interference is reduced, the frequency deviation of each time during the manual locking is avoided, and the recovery speed is high.
Fig. 4 is a flow embodiment of a calcium atomic beam optical frequency scale detection light automatic locking method including state switching, which describes a scanning-locking-unlocking relocking operation mode switching process of the present invention, and in the embodiment of the present invention, a calcium atomic beam optical frequency scale detection light automatic locking method specifically includes the following steps:
In step 201, the scanning range includes a voltage scanning range and a current scanning range, and the external cavity PZT voltage of the laser and the laser tube current are adjusted according to the first voltage step and the first current step to perform scanning within the set voltage scanning range and current scanning range.
In step 202, the rough scanning end condition is that the current sampling point satisfies that the sampling value is greater than or equal to the first threshold, and the absolute value of the difference between the sampling value and the sampling value of the adjacent sampling point is less than the second threshold.
In step 202, if the rough scanning end condition is not satisfied, the scanning is continued until the acquisition point satisfying the rough scanning end condition is found, otherwise, a new scanning range is reset after the preset scanning range is scanned, and the scanning is continued.
And step 203, if the rough scanning end condition is met, ending the rough scanning and starting the fine scanning fluorescence spectral line.
In step 203, the fine scanning of the fluorescence spectrum line refers to adjusting the current of the laser tube to the first current, and adjusting the external cavity PZT voltage of the laser to scan according to the second voltage step between the first bias voltage and the first peak voltage.
And step 204, ending the fine scanning to determine a locking point, and entering a locking mode.
In step 204, a sampling point corresponding to the rear window reference fluorescence signal peak value is determined as a locking point of the front window fluorescence signal, and the laser external cavity PZT voltage corresponding to the locking point is recorded as a second bias voltage.
In step 205, the amplitude of the front window fluorescence signal is collected in real time, and it is detected whether the value of the sampling point is less than or equal to the third threshold, if so, the system is unlocked, otherwise, the system remains in the locking mode.
And step 206, if the amplitude of the acquisition point is lower than a set threshold, entering an unlocking mode, setting a new scanning range, and starting fluorescence spectral line scanning.
In step 206, if the system enters the unlock mode, the new scanning range is set as: the current range is the first current, and the voltage range is between the second peak voltage and the third bias voltage.
And adjusting the current of the laser tube to be the first current, adjusting the external cavity PZT voltage of the laser to scan according to the third voltage step between the second peak voltage and the third bias voltage, and acquiring the amplitude of the front window fluorescence signal.
And step 207, calculating whether the scanned spectral line meets the judgment condition.
In step 207, the fact that the scanned spectral line meets the judgment condition means that the absolute value of the difference between the amplitude of the front window fluorescence signal corresponding to the acquisition point and the external cavity PZT voltage of the laser is less than or equal to a fourth threshold.
In step 207, if the scanned spectral line does not meet the determination condition, the scanning is continued until an acquisition point meeting the determination condition is found or the scanning is completed over the entire new scanning range.
And if the point meeting the judgment condition is not found after the new scanning range is scanned, modifying the new scanning range and continuing scanning.
And step 208, if the scanned spectral line meets the judgment condition, ending the scanning, setting a new locking point, and entering a locking state.
In step 208, after the qualified acquisition point is found, the external cavity PZT voltage and the front window fluorescence signal amplitude corresponding to the acquisition point are recorded.
Note that data at both ends is included between the present invention.
The calcium atomic beam optical frequency scale detection light automatic locking method provided by the embodiment of the invention can realize the functions of automatic fluorescence spectrum line scanning, automatic frequency locking, locking state monitoring and re-locking within 15 seconds after lock loss under the condition that the working temperature of a laser is stable, thereby reducing the requirement on manual monitoring and avoiding excessive manual intervention in an experiment.
It is to be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
The above description is only an example of the present invention, and is not intended to limit the present invention. Various modifications and alterations to this invention will become apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.
Claims (8)
1. A calcium atomic beam optical frequency scale detection light automatic locking method is characterized by comprising the following steps:
the coarse scan determines a first bias voltage and a first current: in a set voltage scanning range and a set current scanning range, adjusting the external cavity PZT voltage of the laser and the current of the laser tube according to a first voltage step and a first current step to scan, and simultaneously acquiring and recording the amplitude of a front window fluorescence signal, if a current sampling point meets the condition that a sampling value is greater than or equal to a first threshold value, and the absolute value of the difference between the sampling value and a sampling value of an adjacent sampling point is smaller than a second threshold value, determining the external cavity PZT voltage of the laser corresponding to the sampling point as the first bias voltage, the current of the corresponding laser tube as the first current, and the voltage value corresponding to the amplitude peak value of the front window fluorescence signal in the scanning process as a first peak voltage;
fine scan determines lock point: adjusting the current of a laser tube to be the first current, adjusting the external cavity PZT voltage of the laser to scan according to the step of a second voltage between the first bias voltage and the first peak voltage, taking a sampling point corresponding to the peak value of the rear window reference fluorescence signal as a locking point of the front window fluorescence signal, and recording the external cavity PZT voltage of the laser corresponding to the locking point as the second bias voltage;
and adjusting the current of the laser tube to be the first current, adjusting the external cavity PZT voltage of the laser to be the second bias voltage, collecting the amplitude of the front window fluorescence signal and the amplitude of the rear window fluorescence reference signal in real time, taking the difference of the two as an error signal, and realizing automatic frequency locking by adopting a PID (proportion integration differentiation) technology.
2. The calcium atom beam optical frequency scale probe light automatic locking method as claimed in claim 1, further comprising:
if the amplitude of the collected front window fluorescence signal is less than or equal to a third threshold value, the frequency is unlocked, and a relocking mode is entered: adjusting the current of the laser tube to be the first current, adjusting the external cavity PZT voltage of the laser according to the third voltage step between the second peak voltage and the third bias voltage to scan, and simultaneously acquiring the amplitude of the front window fluorescence signal, and determining the acquisition point as a re-locking point when the absolute value of the difference between the voltage value corresponding to the amplitude of the front window fluorescence signal corresponding to the acquisition point and the external cavity PZT voltage of the laser is less than or equal to a fourth threshold value;
and the second peak voltage is the voltage corresponding to the amplitude peak value of the front window fluorescence signal in a locked state, and the third bias voltage is the laser external cavity PZT voltage corresponding to the second peak voltage.
3. The calcium atomic beam optical frequency scale probe light automatic locking method according to claim 1, wherein the step of adjusting the external cavity PZT voltage of the laser and the laser tube current in the first voltage step and the first current step for scanning within the set voltage scanning range and current scanning range further comprises:
determining a voltage scan list as [ V ] according to the voltage scan range and the first voltage step1，V2，……，Va]Determining a current sweep list as [ I ] from the current sweep range and the first current step1，I2，……，In]；
Regulating laser tube current to I1Sequentially adjusting the external cavity PZT voltage of the laser to [ V ]1，V2，……，Va]Scanning, if the first bias voltage is not found, adjusting the current of the laser tube to be I2Continuing to scan until the first bias voltage is found or all voltage and current values are traversed;
wherein, V1，V2，……，VaFor the voltage sweep list, I1，I2，……，InThe list is scanned for the current.
4. The method for automatically locking a calcium atom beam optical frequency scale probe light according to claim 1, wherein the first threshold value is 1V or more, and the second threshold value is 0.03V or less.
5. The calcium atomic beam optical frequency scale probe light automatic locking method according to claim 1, wherein the second voltage step is smaller than the first voltage step.
6. The method for automatically locking the calcium atomic beam optical frequency scale detection light as claimed in claim 1, wherein the voltage scanning range is 65V to 70V, the first voltage scanning step is 0.1V, the current scanning range is 47.8 to 48.5mA, and the first current step is 0.1 mA.
7. The calcium atom beam optical frequency scale probe light automatic locking method as claimed in claim 2, wherein the third threshold value is 0.4V or less.
8. The method for automatically locking a calcium atomic beam optical frequency scale probe light according to claim 2, wherein the third bias voltage is 80V or more, the fourth threshold value is 0.01V or less, and the third voltage step is 0.001V or less.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114355753A (en) * | 2021-12-28 | 2022-04-15 | 北京无线电计量测试研究所 | Optical frequency atomic clock closed-loop locking state detection system |
| CN114530752A (en) * | 2022-01-11 | 2022-05-24 | 中国科学院国家授时中心 | Improved mean shift algorithm-based automatic locking system for ultrastable laser |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20080108799A (en) * | 2007-06-11 | 2008-12-16 | 한국표준과학연구원 | Simultaneous transfer of microwave and optical reference frequencies by selectively amplified optical frequency comb |
| CN102821442A (en) * | 2011-06-10 | 2012-12-12 | 联芯科技有限公司 | Scan method and device for frequency points |
| CN103178437A (en) * | 2013-02-27 | 2013-06-26 | 中国科学院武汉物理与数学研究所 | Intelligentialized laser locking device and locking method |
| CN103606814A (en) * | 2013-11-13 | 2014-02-26 | 中国电子科技集团公司第四十一研究所 | Laser frequency stabilization realization method |
| CN105004510A (en) * | 2015-07-02 | 2015-10-28 | 华东师范大学 | Measuring device and measuring method for long-term frequency stability of laser |
| CN204758827U (en) * | 2015-05-29 | 2015-11-11 | 长春理工大学 | A combined type scanning system for laser radar |
| CN108832926A (en) * | 2018-07-09 | 2018-11-16 | 北京无线电计量测试研究所 | A kind of integrated atom beamforming opctical frequency standard |
| CN108917922A (en) * | 2018-07-09 | 2018-11-30 | 北京无线电计量测试研究所 | A kind of quantum measurement method of laser power |
| CN109039469A (en) * | 2018-08-20 | 2018-12-18 | 中国科学院上海光学精密机械研究所 | Time-frequency standard signal merges Transmission system and transmission method |
| CN109301687A (en) * | 2018-11-26 | 2019-02-01 | 中国人民解放军国防科技大学 | Laser automatic frequency stabilization system based on intelligent saturated absorption spectrum identification technology |
| CN109412010A (en) * | 2018-12-14 | 2019-03-01 | 陕西聚力思创通信科技有限公司 | A method of extending the laser frequency stabilizing system mean time between failures |
| CN210926606U (en) * | 2019-12-12 | 2020-07-03 | 山西医科大学 | Laser frequency locking device based on wavelength meter and numerical control feedback |
-
2020
- 2020-09-23 CN CN202011007425.7A patent/CN112260057B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20080108799A (en) * | 2007-06-11 | 2008-12-16 | 한국표준과학연구원 | Simultaneous transfer of microwave and optical reference frequencies by selectively amplified optical frequency comb |
| CN102821442A (en) * | 2011-06-10 | 2012-12-12 | 联芯科技有限公司 | Scan method and device for frequency points |
| CN103178437A (en) * | 2013-02-27 | 2013-06-26 | 中国科学院武汉物理与数学研究所 | Intelligentialized laser locking device and locking method |
| CN103606814A (en) * | 2013-11-13 | 2014-02-26 | 中国电子科技集团公司第四十一研究所 | Laser frequency stabilization realization method |
| CN204758827U (en) * | 2015-05-29 | 2015-11-11 | 长春理工大学 | A combined type scanning system for laser radar |
| CN105004510A (en) * | 2015-07-02 | 2015-10-28 | 华东师范大学 | Measuring device and measuring method for long-term frequency stability of laser |
| CN108832926A (en) * | 2018-07-09 | 2018-11-16 | 北京无线电计量测试研究所 | A kind of integrated atom beamforming opctical frequency standard |
| CN108917922A (en) * | 2018-07-09 | 2018-11-30 | 北京无线电计量测试研究所 | A kind of quantum measurement method of laser power |
| CN109039469A (en) * | 2018-08-20 | 2018-12-18 | 中国科学院上海光学精密机械研究所 | Time-frequency standard signal merges Transmission system and transmission method |
| CN109301687A (en) * | 2018-11-26 | 2019-02-01 | 中国人民解放军国防科技大学 | Laser automatic frequency stabilization system based on intelligent saturated absorption spectrum identification technology |
| CN109412010A (en) * | 2018-12-14 | 2019-03-01 | 陕西聚力思创通信科技有限公司 | A method of extending the laser frequency stabilizing system mean time between failures |
| CN210926606U (en) * | 2019-12-12 | 2020-07-03 | 山西医科大学 | Laser frequency locking device based on wavelength meter and numerical control feedback |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114355753A (en) * | 2021-12-28 | 2022-04-15 | 北京无线电计量测试研究所 | Optical frequency atomic clock closed-loop locking state detection system |
| CN114355753B (en) * | 2021-12-28 | 2024-03-29 | 北京无线电计量测试研究所 | Optical frequency atomic clock closed-loop locking state detection system |
| CN114530752A (en) * | 2022-01-11 | 2022-05-24 | 中国科学院国家授时中心 | Improved mean shift algorithm-based automatic locking system for ultrastable laser |
| CN114530752B (en) * | 2022-01-11 | 2024-05-03 | 中国科学院国家授时中心 | Ultra-stable laser automatic locking system based on improved mean shift algorithm |
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|---|---|
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