Laser pulse energy stabilizing system and laser type gas detector

Abstract

The invention provides a laser pulse energy stabilizing system and method and a laser type gas detector, and the system comprises a laser device which outputs initial pulse laser and has adjustable pulse energy; the first optical splitter is used for splitting the initial pulse into first pulse laser for detection and first pulse laser for working; the laser attenuator is used for carrying out attenuation processing on the received first working pulse laser and outputting attenuated pulse laser; the second optical splitter is used for splitting the attenuated pulse laser into second pulse laser for detection and second pulse laser for working; the pulse energy detection module is used for detecting first pulse energy of the first detection pulse laser and second pulse energy of the second detection pulse; and the control module is respectively connected with the laser and the laser attenuator and is used for regulating and controlling the pulse energy of the initial pulse laser output by the laser and the attenuation multiple of the laser attenuator, so that the pulse energy of the second working pulse laser is kept stable.

Description

Technical Field

[0001] The present disclosure relates to the field of laser technology, and particularly relates to a laser pulse energy stabilization system and method, and a laser gas detector. Background Art

[0002] A laser gas detector can detect atmospheric components based on a laser beam, which is extremely crucial in environmental monitoring. A laser is one of the core components in a laser gas detector. In practical applications, it is found that the lasers in existing laser gas detectors often have the following problems:

[0003] First, the laser is a non-adjustable output laser (taking a common current-controlled laser as an example, the control current inside the current-controlled laser always remains constant). During long-term operation, the laser will gradually age itself, resulting in a continuous decrease in the pulse energy of the actually output laser, leading to a continuous decrease in the pulse energy of the laser output by the laser gas detector finally, and the feedback signal generated by the interaction between the laser and the atmospheric components becomes weaker. This not only reduces the detection sensitivity and makes it difficult to detect low-concentration atmospheric components, but also causes the measurement accuracy to deteriorate and the data reliability to be greatly discounted.

[0004] Second, in order to ensure the sensitivity and detection accuracy of the laser gas detector, once the laser shows slight aging, the laser needs to be replaced, that is, the service life of the laser is short and it needs to be replaced frequently. This not only increases the high cost, but also causes the interruption of monitoring data, seriously affecting the analysis of the long-term change trend of atmospheric components. Summary of the Invention

[0005] The present disclosure aims to at least solve one of the technical problems existing in the prior art, and provides a laser pulse energy stabilization system and method, and a laser gas detector.

[0006] In a first aspect, an embodiment of the present disclosure provides a laser pulse energy stabilization system, including:

[0007] A laser, configured to output an initial pulsed laser, and the pulse energy of the output initial pulsed laser is adjustable;

[0008] A first optical splitter, disposed on the optical path between the laser and the laser attenuator, configured to split the initial pulsed laser into a first detection pulsed laser and a first working pulsed laser according to a first preset splitting ratio;

[0009] A laser attenuator, configured to attenuate the received first working pulsed laser and output an attenuated pulsed laser;

[0010] A second optical splitter, disposed on the output optical path of the laser attenuator, for splitting the attenuated pulsed laser into a second pulsed laser for detection and a second pulsed laser for operation according to a second preset splitting ratio;

[0011] A pulsed energy detection module, configured to detect a first pulsed energy of the first pulsed laser for detection and a second pulsed energy of the second pulsed laser for detection;

[0012] A control module, respectively connected to the laser and the laser attenuator, for regulating the pulsed energy of the initial pulsed laser output by the laser and the attenuation multiple of the laser attenuator, so as to keep the pulsed energy of the second pulsed laser for operation stable.

[0013] In some embodiments, the control module is further connected to the pulsed energy detection module, and the control module is further configured to obtain the first pulsed energy and the second pulsed energy from the pulsed energy detection module.

[0014] In some embodiments, the control module is specifically configured to regulate the pulsed energy of the initial pulsed laser output by the laser and the attenuation multiple of the laser attenuator according to the first pulsed energy and the second pulsed energy;

[0015] The control module includes:

[0016] A first determination unit, configured to obtain the current second pulsed energy of the second pulsed laser for detection, and determine the current pulsed energy of the second pulsed laser for operation according to the obtained second pulsed energy and the second preset splitting ratio;

[0017] A first detection unit, configured to detect whether the current pulsed energy of the second pulsed laser for operation is within a preset stable operating pulsed energy range;

[0018] A first control unit, configured to control the laser to maintain the current control current and control the laser attenuator to maintain the current attenuation multiple when the first detection unit detects that the current pulsed energy of the second pulsed laser for operation is within the preset stable operating pulsed energy range;

[0019] A second determination unit, configured to, when the first detection unit detects that the current pulse energy of the second working pulsed laser is outside the preset stable working pulse energy range, obtain the current first pulse energy of the first detection pulsed laser, and determine the current pulse energy of the first working pulsed laser according to the obtained first pulse energy and the first preset splitting ratio; and determine the pulse energy of the ideal attenuated pulsed laser according to the preset target stable pulse energy and the second preset splitting ratio; wherein, the current pulse energy of the first working pulsed laser is equal to the quotient of the first pulse energy and the first preset splitting ratio, and the pulse energy of the ideal attenuated pulsed laser is equal to the product of the sum of 1 plus the second preset splitting ratio and the preset target stable pulse energy;

[0020] A second detection unit, configured to calculate the quotient of the current pulse energy of the first working pulsed laser and the pulse energy of the ideal attenuated pulsed laser to obtain a first calculation result, and detect whether the first calculation result is within the adjustable range of the attenuation multiple of the laser attenuator.

[0021] A second control unit, configured to, when the second detection unit detects whether the first calculation result is within the adjustable range of the attenuation multiple of the laser attenuator, control the laser to maintain the current control current, and control the attenuation multiple of the laser attenuator to be adjusted to the first calculation result;

[0022] A third control unit, configured to, when the second detection unit detects that the first calculation result is less than the lower limit value of the adjustable range of the attenuation multiple of the laser attenuator, control the laser to increase the current control current by a first preset adjustment amount, and control the laser attenuator to maintain the current attenuation multiple;

[0023] A fourth control unit, configured to, when the second detection unit detects that the first calculation result is greater than the upper limit value of the adjustable range of the attenuation multiple of the laser attenuator, control the laser to decrease the current control current by a second preset adjustment amount, and control the laser attenuator to maintain the current attenuation multiple.

[0024] In some embodiments, the pulse energy detection module includes: a first photodetector and a second photodetector that are independent of each other;

[0025] The first photodetector is disposed on the optical path of the first detection pulsed laser, and is configured to receive the first detection pulsed laser and determine the first pulse energy of the first detection pulsed laser;

[0026] The second photodetector is disposed on the optical path of the second detection pulsed laser, and is configured to receive the second detection pulsed laser and determine the second pulse energy of the second detection pulsed laser.

[0027] In some embodiments, the laser is a current-controlled laser, and the pulse energy of the initial pulsed laser output by the laser increases as the control current increases;

[0028] The control module controls the pulse energy of the initial pulsed laser output by the laser by adjusting the control current of the laser.

[0029] In some embodiments, the control current of the laser is configured to be continuously adjustable within a corresponding adjustable range;

[0030] Alternatively, the control current of the laser is configured to be discretely adjustable within a corresponding adjustable range.

[0031] In some embodiments, the laser is an LD side-pumped electro-optic Q-switched infrared laser.

[0032] In some embodiments, the minimum attenuation multiple of the laser attenuator is 2 times, and the maximum attenuation multiple of the laser attenuator is 100 times.

[0033] In some embodiments, the attenuation multiple of the laser attenuator is configured to be continuously adjustable within a corresponding adjustable range.

[0034] In some embodiments, the value range of the first preset splitting ratio is: [1:99, 1:9];

[0035] The value range of the second preset splitting ratio is: [1:99, 1:9].

[0036] In a second aspect, an embodiment of the present disclosure further provides a method for stabilizing the laser pulse energy. Based on the laser pulse energy stabilization system provided in the previous embodiments, the method for stabilizing the laser pulse energy includes:

[0037] Step S1, obtain the current second pulse energy of the second detection pulsed laser, and determine the current pulse energy of the second working pulsed laser according to the obtained second pulse energy and the second preset splitting ratio;

[0038] Step S2, detect whether the current pulse energy of the second working pulsed laser is within a preset stable working pulse energy range;

[0039] If it is detected that the current pulse energy of the second working pulsed laser is within the preset stable working pulse energy range, then execute step S3; if it is detected that the current pulse energy of the second working pulsed laser is outside the preset stable working pulse energy range, execute step S4.

[0040] Step S3, control the laser to maintain the current control current, and control the laser attenuator to maintain the current attenuation multiple;

[0041] Step S4: Obtain the current first pulse energy of the first detection pulsed laser, and determine the current pulse energy of the first working pulsed laser based on the obtained first pulse energy and the first preset splitting ratio; and determine the pulse energy of the ideal attenuated pulsed laser according to the preset target stable pulse energy and the second preset splitting ratio;

[0042] Among them, the current pulse energy of the first working pulsed laser is equal to the quotient of the first pulse energy and the first preset splitting ratio, and the pulse energy of the ideal attenuated pulsed laser is equal to the product of the sum of 1 plus the second preset splitting ratio and the preset target stable pulse energy;

[0043] Step S5: Calculate the quotient of the current pulse energy of the first working pulsed laser and the pulse energy of the ideal attenuated pulsed laser to obtain a first calculation result, and detect whether the first calculation result is within the adjustable range of the attenuation multiple of the laser attenuator;

[0044] If it is detected that the first calculation result is within the adjustable range of the attenuation multiple of the laser attenuator, then execute step S6a; if it is detected that the first calculation result is less than the lower limit value of the adjustable range of the attenuation multiple of the laser attenuator, then execute step S6b; if it is detected that the first calculation result is greater than the upper limit value of the adjustable range of the attenuation multiple of the laser attenuator, then execute step S6c;

[0045] Step S6a: Control the laser to maintain the current control current, and control the attenuation multiple of the laser attenuator to be adjusted to the first calculation result;

[0046] Step S6b: Control the laser to increase the current control current by a first preset adjustment amount, and control the laser attenuator to maintain the current attenuation multiple;

[0047] After step S6b ends, execute step S1 again;

[0048] Step S6c: Control the laser to decrease the current control current by a second preset adjustment amount, and control the laser attenuator to maintain the current attenuation multiple;

[0049] After step S6c ends, execute step S1 again.

[0050] In a third aspect, an embodiment of the present disclosure provides a laser gas detector, including: the laser pulse energy stabilization system provided in the first aspect as described above.

[0051] The technical solution of the present disclosure can support the detection personnel to calculate the pulse energy of the initial pulsed laser actually output by the laser, the pulse energy of the pulsed laser of the first working pulsed laser, the pulse energy of the pulsed laser actually output by the laser attenuator, and the pulse energy of the second working pulsed laser according to the first pulse energy and the second pulse energy, and accordingly, the control module is used to adjust the pulse energy of the initial pulsed laser output by the laser and the attenuation multiple of the laser attenuator, so as to control the pulse energy of the second working pulsed laser to remain stable.

[0052] In addition, in the present disclosure, even if problems such as laser aging and abnormal operation occur, the control module can also adjust the output of the laser and the attenuation multiple of the laser attenuator to maintain the pulse energy of the second working pulsed laser stable, without replacing the laser, thereby effectively extending the service life of the laser and reducing the replacement frequency. Brief Description of the Drawings

[0053] Figure 1 It is a schematic structural diagram of a laser pulse energy stabilization system provided by an embodiment of the present disclosure;

[0054] Figure 2 It is a schematic structural diagram of another laser pulse energy stabilization system provided by an embodiment of the present disclosure;

[0055] Figure 3 It is a flowchart of a method for the control module to adjust the control current of the laser and the attenuation multiple of the laser attenuator in an embodiment of the present disclosure. Detailed Embodiments

[0056] To enable those skilled in the art to better understand the technical solution of the present disclosure, the present disclosure will be further described in detail below with reference to the drawings and specific embodiments.

[0057] Unless otherwise defined, technical terms or scientific terms used in this disclosure shall have the ordinary meanings as understood by those of ordinary skill in the art to which this disclosure pertains. The "first", "second" and similar terms used in this disclosure do not denote any order, quantity or importance, but are only used to distinguish different components. Similarly, terms such as "a", "an" or "the" do not denote a quantity limitation, but mean that there is at least one. Words such as "comprising" or "including" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. Words such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0058] In the respective drawings, the same elements are denoted by like reference numerals. For clarity, not all parts in the drawings are drawn to scale. In addition, some well-known parts may not be shown in the figures.

[0059] In the following, many specific details of this disclosure are described in order to understand this disclosure more clearly. However, as those skilled in the art can understand, this disclosure can be implemented without these specific details.

[0060] In the following description, the splitting ratio of the optical splitter refers to the pulse energy ratio of the detected pulsed laser and the working pulsed laser split from the original laser. The attenuation multiple of the optical attenuator refers to the ratio of the pulse energy of the pulsed laser input to the laser attenuator to the pulse energy of the pulsed laser output by the laser attenuator.

[0061] Figure 1 This is a schematic structural diagram of a laser pulse energy stabilization system provided for an embodiment of this disclosure. As Figure 1 shown, the laser pulse energy stabilization system includes: a laser, a first optical splitter, a laser attenuator, a second optical splitter, a pulse energy detection module and a control module.

[0062] Among them, the laser is used to output an initial pulsed laser, and the pulse energy of the output initial pulsed laser is adjustable;

[0063] The first optical splitter is disposed on the optical path between the laser and the laser attenuator, and the first optical splitter is used to split the initial pulsed laser into a first detected pulsed laser and a first working pulsed laser according to a first preset splitting ratio.

[0064] The laser attenuator is used to attenuate the received first working pulsed laser and output an attenuated pulsed laser.

[0065] The second optical splitter is arranged on the output optical path of the laser attenuator and is used to split the attenuated pulsed laser into a second detection pulsed laser and a second working pulsed laser according to a second preset splitting ratio.

[0066] The pulse energy detection module is used to detect the first pulse energy of the first detection pulsed laser and the second pulse energy of the second detection pulse.

[0067] The control module is respectively connected to the laser and the laser attenuator. The control module is used to regulate the pulse energy of the initial pulsed laser output by the laser and the attenuation multiple of the laser attenuator so that the pulse energy of the second working pulsed laser remains stable, that is, the pulse energy of the second working pulsed laser remains within the required preset stable working pulse energy range.

[0068] It should be noted that in the attached drawings, the laser is located on the left side of the laser attenuator, the pulse energy detection module is located above the laser, and the control module is located below the laser. These situations are only an example of the attached drawings in this disclosure and will not limit the technical solutions of this disclosure.

[0069] In this disclosure, the first detection pulsed laser is used as a sample of the initial pulsed laser output by the laser. Through the pulse energy detection module, the first detection pulsed laser can be obtained and the corresponding first pulse energy can be determined. Based on the first preset splitting ratio of the first optical splitter, the second pulse energy of the first working pulsed laser and the pulse energy of the initial pulsed laser actually output by the laser can be determined.

[0070] Taking the first preset splitting ratio as 1:a as an example, when the first pulse energy of the first detection pulsed laser is E1, the pulse energy of the first working pulsed laser is a*E1, and in the case of not considering the optical loss during the splitting process, the pulse energy of the initial pulsed laser is (a + 1)*E1.

[0071] Similarly, based on the second preset splitting ratio of the second optical splitter and the second pulse energy of the second detection pulsed laser determined by the pulse energy detection module, the second pulse energy of the first working pulsed laser and the pulse energy of the initial pulsed laser actually output by the laser can be determined.

[0072] Taking the second preset splitting ratio as 1:b as an example, when the second pulse energy of the second detection pulsed laser is E2, the pulse energy of the second working pulsed laser is b*E2, and in the case of not considering the optical loss during the splitting process, the pulse energy of the pulsed laser actually output by the laser attenuator is (b + 1)*E2.

[0073] Based on the above, when the detector obtains the first pulse energy E1 of the first detection pulsed laser and the second pulse energy E2 of the second detection pulsed laser through the pulse energy detection module, the pulse energy of the initial pulsed laser actually output by the laser (a + 1)*E1, the pulse energy of the pulsed laser of the first working pulsed laser a*E1, the pulse energy of the pulsed laser actually output by the laser attenuator (b + 1)*E2, and the pulse energy of the second working pulsed laser b*E2 can be calculated. Based on these data, the detector can send corresponding control signals to the laser and the laser attenuator respectively through the control module to control the output of the laser and the output of the laser attenuator, so as to keep the pulse energy of the second working pulsed laser stable.

[0074] Specifically, when the pulse energy of the second working pulsed laser calculated is within the preset stable working pulse energy range, the pulse energy of the initial pulsed laser output by the laser is maintained unchanged and the attenuation multiple of the laser attenuator is maintained.

[0075] When the pulse energy of the second working pulsed laser calculated is less than the lower limit value of the preset stable working pulse energy range, the pulse energy of the initial pulsed laser output by the laser can be appropriately increased while keeping the attenuation multiple of the laser attenuator unchanged, or the attenuation multiple of the laser attenuator can be appropriately decreased while keeping the pulse energy of the initial pulsed laser output by the laser unchanged, or the pulse energy of the initial pulsed laser output by the laser attenuator and the attenuation multiple of the laser attenuator can be adjusted accordingly (considering that the low pulse energy of the second working pulsed laser is mostly due to the aging of the laser, resulting in a decrease in the pulse energy of the initial pulsed laser actually output, so generally the pulse energy of the initial pulsed laser output by the laser is increased, and at this time the attenuation multiple of the laser attenuator may need to be increased or decreased) to increase the pulse energy of the second working pulsed laser to within the preset stable working pulse energy range.

[0076] When the calculated pulse energy of the second working pulsed laser is greater than the upper limit of the preset stable working pulse energy range (for example, when the laser has an abnormal operation), the pulse energy of the initial pulsed laser output by the laser can be appropriately reduced while keeping the attenuation multiple of the laser attenuator unchanged, or the attenuation multiple of the laser attenuator can be appropriately increased while keeping the pulse energy of the initial pulsed laser output by the laser unchanged, or both the pulse energy of the initial pulsed laser output by the laser attenuator and the attenuation multiple of the laser attenuator can be adjusted accordingly (considering that the relatively high pulse energy of the second working pulsed laser is generally due to the abnormal operation of the laser, resulting in an increase in the pulse energy of the actually output initial pulsed laser, so generally the pulse energy of the initial pulsed laser output by the laser is reduced, and at this time, the attenuation multiple of the laser attenuator may need to be increased or decreased) to adjust the pulse energy of the second working pulsed laser to within the preset stable working pulse energy range.

[0077] Based on the above, it can be seen that the technical solution of the present disclosure enables the detection personnel to calculate the pulse energy of the initial pulsed laser actually output by the laser, the pulse energy of the first working pulsed laser, the pulse energy of the pulsed laser actually output by the laser attenuator, and the pulse energy of the second working pulsed laser based on the first pulse energy and the second pulse energy, and accordingly, through the control module, to regulate the pulse energy of the initial pulsed laser output by the laser and the attenuation multiple of the laser attenuator, so as to keep the pulse energy of the second working pulsed laser stable.

[0078] In addition, in the present disclosure, even if problems such as laser aging and abnormal operation occur, the control module can be used to regulate the output of the laser and the attenuation multiple of the laser attenuator to keep the pulse energy of the second working pulsed laser stable without replacing the laser, thereby effectively extending the service life of the laser and reducing the replacement frequency.

[0079] In addition, based on the calculated pulse energy of the first working pulsed laser and the pulse energy of the attenuated pulsed laser actually output by the laser attenuator in the present disclosure, the actual attenuation multiple of the laser attenuator can also be effectively calculated. By comparing the actual attenuation multiple of the laser attenuator with the set attenuation multiple configured (configured by the control module) of the laser attenuator, it can be determined whether the laser attenuator has an abnormal operation, which can provide a certain basis for the detection personnel to regulate the laser attenuator; for example, if the actual attenuation multiple is equal to the set attenuation multiple, it indicates that the laser attenuator is working normally; otherwise, it indicates that the laser attenuator is working abnormally.

[0080] When the laser attenuator malfunctions, a certain compensation amount can be applied during the regulation of the laser attenuator. For example, if it is pre-detected that the actual attenuation multiple is greater than the set attenuation multiple, and when it is desired that the actual attenuation multiple of the laser attenuator is c1, the control module can send a control instruction to the laser attenuator to indicate that the set attenuation multiple is d1 (the specific value is set according to the actual situation), where d1 is less than c1; if it is pre-detected that the actual attenuation multiple is greater than the set attenuation multiple, and when it is desired that the actual attenuation multiple of the laser attenuator is c2, the control module can send a control instruction to the laser attenuator to indicate that the set attenuation multiple is d2 (the specific value is set according to the actual situation), where d2 is greater than c.

[0081] In some embodiments, considering that the pulsed laser for detection is used for sampling detection, while the pulsed laser for work is used for actual work, in order to ensure the laser utilization rate, the ratio of the pulsed laser for detection to the pulsed laser for work separated from the same laser should be as small as possible. However, at the same time, it is necessary to avoid the problem that the pulsed laser for detection is difficult to be detected due to too small energy. Based on the above considerations, the value range (including the endpoint values) of the first preset splitting ratio in the present disclosure is: [1:99, 1:9]; the value range (including the endpoint values) of the second preset splitting ratio is: [1:99, 1:9].

[0082] In the present disclosure, the specific values of the first preset splitting ratio and the second preset splitting ratio can be preset and adjusted according to actual needs. For example, the values of both the first preset splitting ratio and the second preset splitting ratio are 1:99.

[0083] In some embodiments, the pulsed energy detection module includes: a first photodetector and a second photodetector that are independent of each other. Among them, the first photodetector is arranged on the optical path of the first pulsed laser for detection, and is used to receive the first pulsed laser for detection and determine the first pulsed energy of the first pulsed laser for detection; the second photodetector is arranged on the optical path of the second pulsed laser for detection, and is used to receive the second pulsed laser for detection and determine the second pulsed energy of the second pulsed laser for detection.

[0084] In the present disclosure, the photodetector can receive the pulsed laser and output an electrical signal corresponding to the pulsed energy.

[0085] It should be noted that the above-mentioned pulse energy detection module including two independent photodetectors is only an optional implementation in the present disclosure. In the present disclosure, other methods can also be used to detect the first / second detection pulse lasers. For example, only one photodetector and a movable device are provided, and the photodetector is driven by the movable device to move to detect the pulse energy of the first detection pulse laser and the pulse energy of the second detection pulse laser respectively; for other cases, no further examples will be given here.

[0086] In some embodiments, the laser is a current-controlled laser, and the pulse energy of the initial pulse laser output by the laser increases with the increase of the control current; the control module controls the pulse energy of the initial pulse laser output by the laser by adjusting the control current of the laser.

[0087] In some embodiments, the laser is an LD side-pumped electro-optic Q-switched infrared laser, and the corresponding control current is the LD current. The LD side-pumped electro-optic Q-switched infrared laser modulates the laser pulse based on pump energy control and electro-optic Q-switching technology. Specifically, light with a specific wavelength emitted by a laser diode (LD) irradiates the laser gain medium from the side. The side-pumping method can make the pump light distribute more uniformly in the gain medium, and a higher single-pulse energy can be obtained by increasing the pump power (pumping principle); in addition, the Q value (also called "quality factor") of the laser resonator is controlled through the electro-optic effect. During the pumping stage, the Q value of the resonator is set to a lower state, so that a large number of particles in the laser medium accumulate, forming an inverted population distribution. When the particle number accumulates to a certain extent, the state of the electro-optic element is quickly changed, so that the Q value of the resonator is instantly increased. At this time, the photons in the cavity quickly obtain gain, generating a giant pulse laser output (electro-optic Q-switching principle).

[0088] In some embodiments, the control current of the laser is configured to be continuously adjustable (Continuous Adjustment) within the corresponding adjustable range. As an example, the adjustable range (including the endpoint values) of the control current is 8A to 12A, and the specific value of the control current can be any value within 8A to 12A.

[0089] In some other embodiments, the control current of the laser is configured to be discretely adjustable (Discrete Adjustment) within the corresponding adjustable range. As an example, the adjustable range (including the endpoint values) of the control current is 8A to 12A, and the specific value of the control current can be any of the five values of 8A, 9A, 10A, 11A, and 12A.

[0090] In some embodiments, the minimum attenuation multiple of the laser attenuator is 2 times, and the maximum attenuation multiple of the laser attenuator is 100 times.

[0091] Further optionally, the attenuation multiple of the laser attenuator is configured to be continuously adjustable within the corresponding adjustable range. As an example, the adjustable range (including the end point values) of the attenuation multiple is 2 to 100 times, and the specific value of the attenuation multiple can be any value between 2 and 100 times.

[0092] Figure 2 The structural schematic diagram of another laser pulse energy stabilization system provided by the embodiments of the present disclosure. As Figure 2 shown, the control module is further connected to the pulse energy detection module, and the control module is further configured to obtain the first pulse energy and the second pulse energy from the pulse energy detection module.

[0093] Further optionally, the control module can also be configured to regulate the pulse energy of the initial pulsed laser output by the laser and the attenuation multiple of the laser attenuator according to the first pulse energy and the second pulse energy.

[0094] Optionally, the laser is a current-controlled laser, and the control module can be configured to regulate the control current of the laser and the attenuation multiple of the laser attenuator according to the first pulse energy and the second pulse energy.

[0095] Figure 3 The flowchart of a method for the control module to regulate the control current of the laser and the attenuation multiple of the laser attenuator in the embodiments of the present disclosure. As Figure 3 shown, the control method includes:

[0096] Step S1: Obtain the current second pulse energy of the second detection pulsed laser, and determine the current pulse energy of the second working pulsed laser according to the obtained second pulse energy and the second preset splitting ratio.

[0097] Wherein, the current pulse energy of the second working pulsed laser is equal to the quotient of the second pulse energy and the second preset splitting ratio. Taking the second pulse energy as E2 and the second preset splitting ratio as 1:b as an example, the pulse energy of the second working pulsed laser is b*E2.

[0098] Step S2: Detect whether the current pulse energy of the second working pulsed laser is within the preset stable working pulse energy range.

[0099] If it is detected that the current pulse energy of the second working pulsed laser is within the preset stable working pulse energy range (including the end point values), it indicates that the laser output is stable, and step S3 is executed; if it is detected that the current pulse energy of the second working pulsed laser is outside the preset stable working pulse energy range, step S4 is executed.

[0100] Step S3: Control the laser to maintain the current control current, and control the laser attenuator to maintain the current attenuation multiple.

[0101] Step S4: Obtain the current first pulse energy of the first pulsed laser for detection, and determine the current pulse energy of the first pulsed laser for operation according to the obtained first pulse energy and the first preset splitting ratio; and determine the pulse energy of the ideal attenuated pulsed laser according to the preset target stable pulse energy and the second preset splitting ratio.

[0102] Among them, the current pulse energy of the first pulsed laser for operation is equal to the quotient of the first pulse energy and the first preset splitting ratio. Taking the first pulse energy as E1 and the first preset splitting ratio as 1:a as an example, the pulse energy of the first pulsed laser for operation is a*E2.

[0103] The pulse energy of the ideal attenuated pulsed laser is equal to the product of the sum of 1 plus the second preset splitting ratio and the preset target stable pulse energy. Taking the preset target stable pulse energy as Et and the second preset splitting ratio as 1:b as an example, the pulse energy of the ideal attenuated pulsed laser is (1 + 1 / b)*Et.

[0104] Among them, the value of the preset target stable pulse energy is a value within the preset stable operating pulse energy range; the specific value can be preset according to actual needs. For example, the value of the preset target stable pulse energy is the intermediate value (the average of the two end values) of the preset stable operating pulse energy range.

[0105] After step S4 is completed, step S5 is executed.

[0106] Step S5: Calculate the quotient of the current pulse energy of the first pulsed laser for operation and the pulse energy of the ideal attenuated pulsed laser to obtain a first calculation result, and detect whether the first calculation result is within the adjustable range of the attenuation multiple of the laser attenuator.

[0107] The first calculation result represents the attenuation multiple of the laser attenuator required under the current pulse energy of the first pulsed laser for operation and the ideal attenuated pulsed laser.

[0108] If it is detected that the first calculation result is within the adjustable range of the attenuation multiple of the laser attenuator, then step S6a is executed; if it is detected that the first calculation result is less than the lower limit value of the adjustable range of the attenuation multiple of the laser attenuator, then step S6b is executed; if it is detected that the first calculation result is greater than the upper limit value of the adjustable range of the attenuation multiple of the laser attenuator, then step S6c is executed.

[0109] Step S6a: Control the laser to maintain the current control current, and control the attenuation multiple of the laser attenuator to be adjusted to the first calculation result.

[0110] Step S6b: Control the laser to increase the current control current by a first preset adjustment amount, and control the laser attenuator to maintain the current attenuation multiple.

[0111] After step S6b ends, step S1 is executed again.

[0112] If it is determined that the first calculation result is less than the lower limit value of the adjustable range of the attenuation multiple of the laser attenuator, the control current should be increased so that the pulse energy of the pulsed laser output by the laser increases, so that the first calculation result increases.

[0113] The first preset adjustment amount can be designed accordingly according to the characteristics of the laser. For example, the first preset adjustment amount can be 1A, that is, in step S6b, the current control current of the laser is increased by 1A.

[0114] In step S6c, control the laser to lower the current control current by a second preset adjustment amount, and control the laser attenuator to maintain the current attenuation multiple.

[0115] After step S6c ends, step S1 is executed again.

[0116] If it is determined that the first calculation result is greater than the upper limit value of the adjustable range of the attenuation multiple of the laser attenuator, the control current should be decreased so that the pulse energy of the pulsed laser output by the laser decreases, so that the first calculation result decreases.

[0117] The second preset adjustment amount can be designed accordingly according to the characteristics of the laser. For example, the second preset adjustment amount can be 1A, that is, in step S6c, the current control current of the laser is decreased by 1A.

[0118] It should be noted that in practical applications, the specific value range of the preset stable working pulse energy range is set according to the actual required "stability"; of course, in some specific cases, the preset stable working pulse energy range can be a specific value (that is, the lower limit value and the upper limit value of the range are equal), and this situation will not affect the technical solution of the present disclosure.

[0119] Through the above algorithm, when the current pulse energy of the second working pulsed laser is outside the preset stable working pulse energy range, the attenuation multiple of the attenuator can be maintained and / or the current control current of the laser can be effectively adjusted so that the current pulse energy of the second working pulsed laser is stabilized within the preset stable working pulse energy range.

[0120] Based on the same inventive concept, the embodiments of the present disclosure also provide a laser gas detector. The laser gas detector includes a laser pulse energy stabilization system, and the laser pulse energy stabilization system adopts the laser pulse energy stabilization system provided in the previous embodiments, and the specific content can be referred to the foregoing content.

[0121] By adopting the foregoing laser pulse energy stabilization system, the stability of the laser pulses output by the laser gas detector can be effectively ensured, and the sensitivity and detection accuracy of the laser gas detector can be guaranteed.

[0122] It can be understood that the above embodiments are merely exemplary embodiments adopted to illustrate the principles of the present disclosure. However, the present disclosure is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present disclosure, and these modifications and improvements are also regarded as the protection scope of the present disclosure.

Claims

1. A laser pulse energy stabilization system, characterized in that, Including: A laser for outputting an initial pulsed laser, and the pulse energy of the output initial pulsed laser is adjustable; A first optical splitter disposed on the optical path between the laser and the laser attenuator for splitting the initial pulsed laser into a first pulsed laser for detection and a first pulsed laser for operation according to a first preset splitting ratio; A laser attenuator for attenuating the received first pulsed laser for operation and outputting an attenuated pulsed laser; A second optical splitter disposed on the output optical path of the laser attenuator for splitting the attenuated pulsed laser into a second pulsed laser for detection and a second pulsed laser for operation according to a second preset splitting ratio; A pulse energy detection module for detecting the first pulse energy of the first pulsed laser for detection and the second pulse energy of the second pulsed laser for detection; A control module respectively connected to the laser and the laser attenuator for regulating the pulse energy of the initial pulsed laser output by the laser and the attenuation multiple of the laser attenuator so that the pulse energy of the second pulsed laser for operation remains stable.

2. The laser pulse energy stabilization system according to claim 1, characterized in that, The control module is further connected to the pulse energy detection module, and the control module is further configured to obtain the first pulse energy and the second pulse energy from the pulse energy detection module.

3. The laser pulse energy stabilization system according to claim 2, wherein, The control module is specifically configured to regulate the pulse energy of the initial pulsed laser output by the laser and the attenuation multiple of the laser attenuator according to the first pulse energy and the second pulse energy; The control module includes: A first determination unit for obtaining the current second pulse energy of the second pulsed laser for detection and determining the current pulse energy of the second pulsed laser for operation according to the obtained second pulse energy and the second preset splitting ratio; A first detection unit for detecting whether the current pulse energy of the second pulsed laser for operation is within a preset stable operating pulse energy range; A first control unit for controlling the laser to maintain the current control current and controlling the laser attenuator to maintain the current attenuation multiple when the first detection unit detects that the current pulse energy of the second pulsed laser for operation is within the preset stable operating pulse energy range; A second determination unit for, when the first detection unit detects that the current pulse energy of the second pulsed laser for operation is outside the preset stable operating pulse energy range, obtaining the current first pulse energy of the first pulsed laser for detection and determining the current pulse energy of the first pulsed laser for operation according to the obtained first pulse energy and the first preset splitting ratio; and determining the pulse energy of an ideal attenuated pulsed laser according to a preset target stable pulse energy and the second preset splitting ratio; wherein, the current pulse energy of the first pulsed laser for operation is equal to the quotient of the first pulse energy and the first preset splitting ratio, and the pulse energy of the ideal attenuated pulsed laser is equal to the product of the sum of 1 plus the second preset splitting ratio and the preset target stable pulse energy; A second detection unit, configured to calculate a quotient of the current pulse energy of the first working pulsed laser and the pulse energy of the ideal attenuated pulsed laser to obtain a first calculation result, and detect whether the first calculation result is within the adjustable range of the attenuation multiple of the laser attenuator; A second control unit, configured to control the laser to maintain the current control current and control the attenuation multiple of the laser attenuator to be adjusted to the first calculation result when the second detection unit detects whether the first calculation result is within the adjustable range of the attenuation multiple of the laser attenuator; A third control unit, configured to control the laser to increase the current control current by a first preset adjustment amount and control the laser attenuator to maintain the current attenuation multiple when the second detection unit detects that the first calculation result is less than the lower limit value of the adjustable range of the attenuation multiple of the laser attenuator; A fourth control unit, configured to control the laser to decrease the current control current by a second preset adjustment amount and control the laser attenuator to maintain the current attenuation multiple when the second detection unit detects that the first calculation result is greater than the upper limit value of the adjustable range of the attenuation multiple of the laser attenuator.

4. The laser pulse energy stabilization system according to claim 1, characterized in that, The pulse energy detection module includes: a first photodetector and a second photodetector that are independent of each other; The first photodetector is disposed on the optical path of the first detection pulsed laser, and is configured to receive the first detection pulsed laser and determine a first pulse energy of the first detection pulsed laser; The second photodetector is disposed on the optical path of the second detection pulsed laser, and is configured to receive the second detection pulsed laser and determine a second pulse energy of the second detection pulsed laser.

5. The laser pulse energy stabilization system according to claim 1, wherein The laser is a current-controlled laser, and the pulse energy of the initial pulsed laser output by the laser increases as the control current increases; The control module controls the pulse energy of the initial pulsed laser output by the laser by adjusting the control current of the laser.

6. The laser pulse energy stabilization system according to claim 5, characterized in that, The control current of the laser is configured to be continuously adjustable within a corresponding adjustable range; Alternatively, the control current of the laser is configured to be discretely adjustable within a corresponding adjustable range.

7. The laser pulse energy stabilization system according to claim 1, characterized in that, The minimum attenuation multiple of the laser attenuator is 2 times, and the maximum attenuation multiple of the laser attenuator is 100 times.

8. The laser pulse energy stabilization system according to claim 1, characterized in that, The attenuation multiple of the laser attenuator is configured to be continuously adjustable within a corresponding adjustable range.

9. A method for stabilizing the energy of a laser pulse, characterized in that, Based on the laser pulse energy stabilization system according to any one of claims 2 or 3, the laser pulse energy stabilization method includes: Step S1, obtaining the current second pulse energy of the second detection pulsed laser, and determining the current pulse energy of the second working pulsed laser according to the obtained second pulse energy and a second preset splitting ratio; Step S2, detecting whether the current pulse energy of the second working pulsed laser is within a preset stable working pulse energy range; If it is detected that the current pulse energy of the second working pulsed laser is within the preset stable working pulse energy range, then step S3 is executed; if it is detected that the current pulse energy of the second working pulsed laser is outside the preset stable working pulse energy range, step S4 is executed. Step S3: Control the laser to maintain the current control current and control the laser attenuator to maintain the current attenuation multiple; Step S4: Obtain the current first pulse energy of the first detection pulsed laser, and determine the current pulse energy of the first working pulsed laser according to the obtained first pulse energy and the first preset splitting ratio; and determine the pulse energy of the ideal attenuated pulsed laser according to the preset target stable pulse energy and the second preset splitting ratio; Wherein, the current pulse energy of the first working pulsed laser is equal to the quotient of the first pulse energy and the first preset splitting ratio, and the pulse energy of the ideal attenuated pulsed laser is equal to the product of the sum of 1 plus the second preset splitting ratio and the preset target stable pulse energy; Step S5: Calculate the quotient of the current pulse energy of the first working pulsed laser and the pulse energy of the ideal attenuated pulsed laser to obtain a first calculation result, and detect whether the first calculation result is within the adjustable range of the attenuation multiple of the laser attenuator; If it is detected that the first calculation result is within the adjustable range of the attenuation multiple of the laser attenuator, then execute Step S6a; if it is detected that the first calculation result is less than the lower limit value of the adjustable range of the attenuation multiple of the laser attenuator, then execute Step S6b; if it is detected that the first calculation result is greater than the upper limit value of the adjustable range of the attenuation multiple of the laser attenuator, then execute Step S6c; Step S6a: Control the laser to maintain the current control current and control the attenuation multiple of the laser attenuator to be adjusted to the first calculation result; Step S6b: Control the laser to increase the current control current by a first preset adjustment amount and control the laser attenuator to maintain the current attenuation multiple; After Step S6b ends, execute Step S1 again; Step S6c: Control the laser to decrease the current control current by a second preset adjustment amount and control the laser attenuator to maintain the current attenuation multiple; After Step S6c ends, execute Step S1 again.

10. A laser gas detector, characterized in that, Including: The laser pulse energy stabilization system according to any one of claims 1 to 8 above.

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