A laser wavelength calibration device

Abstract

The utility model discloses a kind of laser wavelength calibration devices, it is related to laser calibrating technical field, solve the problem of complex detection link structure in prior art.A kind of laser wavelength calibration device, including support seat, the lens and reference detector are correspondingly provided on the support seat, target gas is equipped in the area between lens and reference detector;The support seat is equipped with the slot for limiting the position of laser emitter end, lens is cooperatively arranged in the slot one side and is used to detect the light leakage of laser emitter end.By ingenious use the light leakage characteristic of laser tail cover optical fiber, the light leakage is detected, avoids using separating device such as beam splitter, thereby significantly reduce the loss of laser output optical power, improve the utilization efficiency of optical signal.This not only guarantees the output performance of laser, reduces the complexity of detection link, also reduces the measurement error possibly caused by insufficient optical power, improves the accuracy of gas concentration measurement.

Description

Technical Field

[0001] This utility model relates to the field of laser calibration technology, and in particular to a laser wavelength calibration device. Background Technology

[0002] The beam emitted by a tunable semiconductor laser attenuates when it passes through a target gas due to absorption by gas molecules. Based on the Lambert-Beer law, the concentration of the target gas can be accurately calculated.

[0003] In practical applications, the wavelength of lasers is easily affected by external environmental factors, resulting in wavelength drift. This wavelength drift directly leads to deviations in gas concentration calculations based on absorption spectroscopy. Currently, the commonly used laser wavelength calibration method in the industry involves splitting the laser beam in two using a beam splitter. One beam serves as a reference beam, which is then passed through a sealed reference gas chamber containing a specific concentration of the target gas and irradiated onto a photodetector. By analyzing the absorption characteristics of the reference beam within the reference gas chamber and combining this with the output signal of the photodetector, the laser wavelength is calibrated in real time.

[0004] Chinese utility model patent CN217654726U discloses a laser power detection device, which includes a package, a laser fiber optic armor cable, a laser collimator, a beam splitter, an optical power meter, and a transmission port. The package includes a housing, a cover, and an output port; the cover is fastened to the housing, and the output port is located on the housing. The laser collimator is fixedly installed inside the housing. One end of the laser fiber optic armor cable is connected to the laser collimator, transmitting the laser signal from the receiving end to the collimator. After collimation, the laser signal is emitted as a collimated laser. The beam splitter is located in the optical path of the collimated laser. Part of the collimated laser is reflected by the beam splitter to form the detection laser, and the other part is refracted through the beam splitter to form the working laser. The collimated laser emitted from the collimator is split by the beam splitter, and the optical power meter directly measures the optical power of a portion of the collimated laser, ensuring measurement accuracy.

[0005] However, this approach has significant drawbacks. The use of splitting devices such as beam splitters inevitably leads to a loss of laser output power. Furthermore, the system has a complex structure, involving the precise alignment and adjustment of multiple optical components, making it difficult to manufacture and unsuitable for large-scale applications.

[0006] To reduce the number of link connectors, ensure the output optical power of the laser, improve the reliability of system operation and the feasibility of manufacturing process, a laser wavelength calibration device is designed based on the light leakage characteristics of the tail fiber of tunable semiconductor laser, which has important practical significance and engineering value. Utility Model Content

[0007] To address the shortcomings of the aforementioned background technology, this utility model proposes a laser wavelength calibration device, which solves the problem of complex detection link structure in the prior art.

[0008] The technical solution of this utility model is implemented as follows: a laser wavelength calibration device includes a support base, on which a lens and a reference detector are correspondingly arranged, and a target gas is provided in the area between the lens and the reference detector; the support base is provided with a slot for defining the penetration position of the laser emitting end, and the lens is arranged on one side of the slot and is used to detect light leakage at the laser emitting end.

[0009] Preferably, a reference gas chamber is provided in the area between the lens and the reference detector, and the target gas is filled in the reference gas chamber.

[0010] Preferably, an outer gas cylinder is fixedly mounted on the support base, and a lens and a reference detector are respectively sealed and fixed at both ends of the outer gas cylinder, with the target gas filling the space between the lens and the reference detector. The lens and the outer gas cylinder, and the reference detector and the outer gas cylinder are sealed together by sealing rings or sealant.

[0011] Preferably, the laser includes a laser body, the emitting end of the laser body is provided with a laser tail sleeve, the laser tail sleeve is connected to an optical fiber, and the lens corresponds to the connection point between the laser tail sleeve and the optical fiber.

[0012] Preferably, the slot includes a first slot and a second slot that are connected to each other. The first slot mates with the laser tail sleeve, and the second slot mates with the optical fiber. The connection between the first slot and the second slot is provided with a limiting surface for defining the insertion position of the laser tail sleeve.

[0013] Preferably, the angle between the lens axis and the center line of the second slot is an acute angle. The reference detector is a photodetector. The lens is a convex lens.

[0014] The beneficial effects of this utility model are: By cleverly utilizing the light leakage characteristics of the laser's tail fiber, the leaked light is detected, avoiding the use of separation devices such as beam splitters. This significantly reduces the loss of laser output power and improves the utilization efficiency of the optical signal. This not only ensures the laser's output performance and reduces the complexity of the detection link, but also reduces measurement errors that may be caused by insufficient optical power, thus improving the accuracy of gas concentration measurement.

[0015] Secondly, the device has a simple and compact structure, consisting of only key components such as a support base, lens, reference detector, reference gas chamber, and laser. This greatly reduces the number of complex optical components in traditional calibration systems, such as beam splitters and mirrors, thereby reducing the mechanical complexity of the system, reducing calibration errors, and improving the stability and reliability of calibration.

[0016] In practical applications, users can quickly install and debug the laser. They only need to insert the laser emitter into the slot and ensure that it is aligned with the lens to complete the connection. There is no need for complicated alignment and debugging processes, which saves time and labor costs. Attached Figure Description

[0017] To more clearly illustrate the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the first structure of this utility model; Figure 2 This is a schematic diagram of the second structure of this utility model; In the figure: 1: Laser, 2: Laser tail sleeve, 3: Support base, 4: Lens, 5: Target gas, 6: Reference detector, 7: Fiber optic cable, 8: Lens mounting base, 9: Slot, 10: First slot, 11: Second slot, 12: Limiting surface. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] like Figure 1 , 2 As shown in Embodiment 1, a laser wavelength calibration device includes a support base 3, on which a lens 4 and a reference detector 6 are correspondingly disposed. A target gas 5 is disposed in the area between the lens 4 and the reference detector 6. The type of the target gas is selected according to the wavelength of the laser to be calibrated.

[0021] The support base 3 is provided with a slot 9 for defining the position of the laser 1's emitting end. A lens 4 is disposed on one side of the slot 9 and is used to detect light leakage at the emitting end of the laser 1. Specifically, in this embodiment, the laser 1 includes a laser body, and the emitting end of the laser body is provided with a laser tail sleeve 2. The laser tail sleeve 2 is connected to an optical fiber 7, and the lens 4 corresponds to the connection between the laser tail sleeve 2 and the optical fiber 7.

[0022] In practical use, the laser and reference detector are electrically connected to the microprocessor. The microprocessor can be a conventional single-chip microcomputer for control, so that it can receive feedback information from the reference detector and control the control drive parameters of the laser.

[0023] During actual calibration, a calibration device with a corresponding target gas 5 is first selected based on the laser 1 to be tested. Then, the optical fiber 7 and laser tail sleeve 2 of laser 1 are inserted into slot 9. The microprocessor adjusts the laser's drive current and operating temperature in real time, ensuring the laser can stably output a wavelength matching the absorption peak of the target gas's "fingerprint." The laser emitted from the laser body enters the optical fiber 7 through the laser tail sleeve 2. Due to manufacturing processes and material properties, light leakage occurs at the connection between the laser tail sleeve 2 and the optical fiber 7. The leaked laser light illuminates the lens 4, is focused by the lens, passes through the target gas, and then illuminates the photosensitive surface of the reference detector 6. The reference photodetector 6 converts the received optical signal into an electrical signal, which is then digitally sampled by the microprocessor's acquisition circuit. The microprocessor uses advanced digital lock-in amplification technology to accurately extract the second harmonic information of the target gas in the reference chamber from the acquired signal. By comparing the position of the maximum value of the second harmonic information with the preset threshold range, the microprocessor can determine in real time whether the wavelength of the laser has drifted, and dynamically adjust the driving parameters of the laser accordingly to achieve laser wavelength calibration.

[0024] Example 2: A laser wavelength calibration device, based on Example 1, wherein a reference gas chamber is provided in the area between the lens 4 and the reference detector 6, and the target gas 5 is filled in the reference gas chamber.

[0025] In this embodiment, a reference chamber is independently disposed between the lens and the reference detector, and is fixedly attached to the support base 3 by adhesive or snap-fit. The reference chamber can be a cylindrical or rectangular shell, and the shell can be made of conventional materials such as glass or transparent plastic to allow light to pass through. The lens 4 is fixed to the support base 3 by the lens mounting bracket 8, thereby fixing the position of the lens 4.

[0026] Example 3 provides a laser wavelength calibration device. Based on Example 1, an outer gas cylinder 9 is fixedly mounted on the support base 3. A lens 4 and a reference detector 6 are respectively sealed and fixed at both ends of the outer gas cylinder 9, and the target gas 5 is filled between the lens 4 and the reference detector 6. Furthermore, the lens 4 and the outer gas cylinder 9, and the reference detector 6 and the outer gas cylinder 9 are sealed together by sealing rings or sealant to achieve a seal and prevent target gas leakage.

[0027] In this embodiment, the lens and reference detector are fixedly mounted at the two ends of the outer cylinder of the gas chamber, forming a sealed cavity between them. The target gas is then directly filled into the sealed cavity. Compared to the technical solution of Embodiment 2, this effectively reduces the use of the reference gas chamber, lowers system complexity, and reduces interference with light transmission. Furthermore, by optimizing the optical path structure, it reduces the generation of optical noise, which helps improve the measurement accuracy and stability of the system. As an optional solution, an air inlet can be provided on the outer cylinder of the gas chamber to allow the target gas to be filled into it.

[0028] Example 4: A laser wavelength calibration device, based on Example 2 or 3, wherein the slot 9 includes a first slot 10 and a second slot 11 that are connected. The first slot 10 is engaged with the laser tail sleeve 2, and the second slot 11 is engaged with the optical fiber 7. A limiting surface 12 for limiting the insertion position of the laser tail sleeve 2 is provided at the connection between the first slot 10 and the second slot 11.

[0029] In this embodiment, as an optional solution, both the first slot and the second slot can be U-shaped grooves. The optical fiber and the laser tail sleeve can be inserted from the opening of the U-shaped groove. At the same time, in order to match the size of the optical fiber and the laser tail sleeve, the width of the first slot is smaller than the width of the second slot, and the limiting surface is formed at the connection between the first slot 10 and the second slot 11.

[0030] As an alternative, both the first and second slots are cylindrical slots. During installation, the optical fiber and the laser tail sleeve are inserted from one end of the first slot until they are in contact with the limiting surface.

[0031] Furthermore, the angle between the axis of lens 4 and the center line of the second slot 11 is an acute angle. An opening is provided on the side wall at the connection between the first slot and the second slot to allow leaked laser light to pass through, and the lens corresponds to the opening. In this embodiment, the angle is set to an acute angle, which is beneficial for receiving leaked laser light.

[0032] In addition, the reference detector 6 is a photodetector, which uses its photosensitive surface to receive the light signal of the leaked light and convert it into an electrical signal. The lens 4 is a convex lens, which can focus the light.

[0033] In this embodiment, the target gas 5 can be either methane or ammonia. When using methane, the concentration range can be 0.1% to 100% VOL. According to the HITRA database, the fingerprint absorption wavelength for methane is selected as 1653.7 nm or 1650.9 nm. When the target gas is ammonia, the concentration range can be 0.1% to 100% VOL. According to the HITRA database, the fingerprint absorption wavelength for methane is selected as 1512 nm. In actual use, the concentration and type of the target gas set in this device are selected and determined according to the laser wavelength to be calibrated.

[0034] This device boasts excellent adaptability and scalability. By changing the type of target gas or adjusting its concentration parameters, it can calibrate various laser wavelengths to meet the needs of different application scenarios. Furthermore, its structural design allows for flexible customization and optimization based on actual requirements, reducing manufacturing complexity and production costs. It possesses significant advantages for large-scale production, providing ample room for further development of laser calibration technology and reliable technical support for laser performance optimization and large-scale application.

[0035] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A laser wavelength calibration device, characterized in that: Includes a support base (3), on which a lens (4) and a reference detector (6) are respectively provided. Target gas (5) is provided in the area between the lens (4) and the reference detector (6). The support base (3) is provided with a slot (9) for defining the position of the laser (1) emitting end. The lens (4) is provided on one side of the slot (9) and is used to detect light leakage at the laser (1) emitting end.

2. The laser wavelength calibration device according to claim 1, characterized in that: A reference gas chamber is provided in the area between the lens (4) and the reference detector (6), and the target gas (5) is filled in the reference gas chamber.

3. The laser wavelength calibration device according to claim 1, characterized in that: The support base (3) is fixedly provided with an outer cylinder (9), and the lens (4) and the reference detector (6) are respectively sealed and fixed at both ends of the outer cylinder (9). The target gas (5) is filled between the lens (4) and the reference detector (6).

4. The laser wavelength calibration device according to claim 3, characterized in that: The lens (4) and the outer cylinder (9) of the air chamber, and the reference detector (6) and the outer cylinder (9) of the air chamber are sealed together by a sealing ring or sealant.

5. The laser wavelength calibration device according to any one of claims 1 to 3, characterized in that: The laser (1) includes a laser body, and the emitting end of the laser body is provided with a laser tail sleeve (2). The laser tail sleeve (2) is connected to an optical fiber (7), and the lens (4) corresponds to the connection between the laser tail sleeve (2) and the optical fiber (7).

6. The laser wavelength calibration device according to claim 5, characterized in that: The slot (9) includes a first slot (10) and a second slot (11) that are connected. The first slot (10) is engaged with the laser tail sleeve (2), and the second slot (11) is engaged with the optical fiber (7). The connection between the first slot (10) and the second slot (11) is provided with a limiting surface (12) for limiting the insertion position of the laser tail sleeve (2).

7. The laser wavelength calibration device according to claim 6, characterized in that: The angle between the axis of the lens (4) and the center line of the second slot (11) is an acute angle.

8. The laser wavelength calibration device according to claim 7, characterized in that: The reference detector (6) is a photodetector.

9. The laser wavelength calibration device according to claim 8, characterized in that: The lens (4) is a convex lens.

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