Cassette optical fiber sensor and optical fiber laser thereof

Abstract

The utility model provides a cassette optical fiber sensor and an optical fiber laser thereof, the cassette optical fiber sensor comprises a cover plate, a base and a photoelectric sensor, a first position of the base is provided with a detection window, a detection end of the photoelectric sensor is inserted into the detection window, the base is internally provided with a reflection cavity, the reflection cavity is communicated with the detection window, and the photoelectric sensor is arranged in the reflection cavity. A second position of the base is provided with an optical fiber groove, the optical fiber groove is cut into the base body and stretches across the reflection cavity and the detection window, so that an optical fiber can be embedded into the optical fiber groove, and a part of the optical fiber section is suspended between the detection window and the reflection cavity; therefore, the detection window matched with the photoelectric sensor and the reflection cavity define a dark cavity. Therefore, the working condition of the pumping source is monitored through the scattered light of the monitoring optical fiber.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, in particular to a dark box optical fiber sensor and an optical fiber laser thereof. Background Art

[0002] A fiber laser uses an optical fiber as its gain medium, generating a laser beam by exploiting the high amplification effect and stimulated emission of radiation within the fiber. Fiber lasers offer advantages such as high efficiency, high beam quality, small size and weight, and ease of maintenance. They have found widespread application in a wide range of fields, including materials processing, medicine, communications, radar, and distance measurement.

[0003] Currently, in existing fiber lasers, a pump source with a specific wavelength is generally used to increase the output power of the fiber laser. However, due to the limited absorption coefficient of the gain fiber for pump light, and the fact that the central wavelength of the pump source also changes with changes in current and cooling temperature, when the central wavelength of the pump source changes, the absorption rate of the gain fiber for pump light also changes accordingly.

[0004] Therefore, when the absorption rate of the gain fiber to the pump light fluctuates, it will affect the optical efficiency of the fiber laser. If it is not discovered in time, it may even cause damage to high-power fiber devices such as cladding light strippers and fiber combiners in serious cases, leading to damage to the fiber laser. Utility Model Content

[0005] Therefore, the main purpose of the present invention is to provide a dark box optical fiber sensor and an optical fiber laser thereof, so as to monitor the working condition of the pump source by monitoring the scattered light of the optical fiber.

[0006] In order to achieve the above-mentioned purpose, according to one aspect of the utility model, a dark box optical fiber sensor is provided, which is suitable for matching with optical fiber, comprising: a cover plate, a base, and a photoelectric sensor, wherein a detection window is provided at a first position of the base, and the detection end of the photoelectric sensor is inserted into the detection window, a reflection cavity is provided in the base, and the reflection cavity is connected to the detection window, and an optical fiber groove is provided at a second position of the base, and the optical fiber groove is cut into the base body, spanning the reflection cavity and the detection window for optical fiber embedding, so that part of the optical fiber segment is suspended between the detection window and the reflection cavity, and the cover plate is connected to the base, and covers the optical fiber groove on one side of the base, so that the detection window and the reflection cavity of the matching photoelectric sensor define a dark cavity.

[0007] Preferably, in the dark box optical fiber sensor, the reflective cavity is hemispherical.

[0008] Preferably, in the dark box optical fiber sensor, the photoelectric sensor is a photodiode.

[0009] Preferably, in the dark box optical fiber sensor, the surface of the reflective cavity is mirror-like.

[0010] Preferably, in the dark box optical fiber sensor, the sensing end of the photoelectric sensor is retracted into the detection window to be spaced apart from the bottom opening of the detection window.

[0011] Preferably, in the dark box optical fiber sensor, the inner wall surface of the dark cavity is mirror-like.

[0012] In order to achieve the above-mentioned purpose, according to another aspect of the present invention, a fiber laser is provided, which includes a seed source, a pump light source, a fiber combiner, and an optical resonant cavity connected by optical fibers, and further includes a dark box fiber sensor as described above, wherein the dark box fiber sensor is arranged on the output optical fiber of the pump light source.

[0013] Preferably, in the fiber laser, the dark box fiber sensor is also arranged on the output fiber of the seed source.

[0014] Preferably, in the fiber laser, the dark box fiber sensor is also arranged on the output fiber of the fiber combiner.

[0015] Preferably, in the fiber laser, the dark box fiber sensor is also arranged on the output fiber of the optical resonant cavity.

[0016] Through the dark box optical fiber sensor and its optical fiber laser provided by the utility model, a dark box structure is cleverly designed to collect the Rayleigh scattered light of the optical fiber itself in the dark cavity for non-destructive detection, thereby eliminating the need to strip the optical fiber, facilitating setup and manual operation, and avoiding damage to the optical fiber. At the same time, the dark cavity inside the dark box is a basically closed space, so it can have good anti-interference ability, and has a certain dust and moisture-proof effect inside, thereby ensuring high precision and accuracy of PD detection, thereby ensuring stable monitoring of the working condition of the pump source. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0018] Figure 1 This is a front structural diagram of the dark box optical fiber sensor of the present utility model;

[0019] Figure 2 This is a schematic diagram of the assembly structure of the dark box optical fiber sensor of the present utility model;

[0020] Figure 3 This is a schematic diagram of the base structure of the dark box optical fiber sensor of the present invention;

[0021] Figure 4 This is a side structural diagram of the dark box optical fiber sensor of the present utility model;

[0022] Figures 5 and 6 for Figure 4 Schematic diagram of the side section structure on the AA side.

[0023] Description of Reference Numerals

[0024] Cover plate 1, base 2, photoelectric sensor 3, dark cavity 4, optical fiber 5, detection window 11, reflection cavity 21, optical fiber groove 22. DETAILED DESCRIPTION

[0025] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are also within the scope of protection of the present invention.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0028] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, or are the orientation or positional relationship in which the utility model product is usually placed when in use. They are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance. The terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0029] Furthermore, terms such as "horizontal," "vertical," and "overhanging" do not necessarily imply that a component must be absolutely horizontal or overhanging, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather that it can be slightly tilted.

[0030] In the description of the present invention, it should also be noted that, unless otherwise clearly specified and limited, the terms "setting", "layout", "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood in combination with the existing technology according to the specific circumstances. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other unless there is a conflict. And one or more of the components in the diagram may be necessary or non-essential, and the relative positional relationship between the components in the above diagram can be adjusted according to actual needs.

[0031] In order to monitor the working condition of the pump source by monitoring the optical fiber that transmits the pump light, such as Figures 1 to 4 As shown, the utility model provides a dark box optical fiber sensor, an example of which includes: a cover plate 1, a base 2, and a photoelectric sensor 3, wherein a detection window 11 is provided at a first position of the base 2, and the detection window 11 is used to accommodate the photoelectric sensor 3, so that it can be set to a shape similar to the sensing end of the photoelectric sensor 3 so that it can be inserted into the detection window 11 to form a tight fit.

[0032] A reflection cavity 21 is provided in the base 2, and the reflection cavity 21 is connected to the detection window 11. A fiber optic groove 22 is provided at the second position of the base 2. The fiber optic groove 22 is cut into the body of the base 2 and spans the reflection cavity 21 and the detection window 11. In addition, the size of the fiber optic groove 22 can be adapted and adjusted to the size of the optical fiber at the location to be detected so that the corresponding optical fiber 5 can be embedded.

[0033] The cover plate 1 is connected to the base 2. After the cover is connected to the optical fiber groove 22 on one side of the base 2, the detection window 11 of the photoelectric sensor 3 can be connected to the reflective cavity 21 to form a dark cavity 4. At the same time, the optical fiber at the detection position can be carried by the optical fiber groove 22, so that part of the optical fiber segment is suspended between the detection window 11 and the reflective cavity 21, and part of the segment of the optical fiber 5 is in a shape that spans the reflective cavity 21.

[0034] The dark cavity 4 structure formed by this setting can form a basically closed space inside the dark cavity 4 when the optical fiber 5 is embedded in the optical fiber groove 22, thereby resisting external interference. At the same time, the interior can be dust-proof and moisture-proof to a certain extent to ensure that there is no interference during the photoelectric detection process.

[0035] In addition, if Figure 6 As shown, the design of the dark cavity 4 structure enables the collection of Rayleigh scattered light from the optical fiber itself for non-destructive detection. This eliminates the need to remove the fiber cladding. The faint light emitted during transmission can be collected by reflection from the reflective cavity 21 and directed to the photoelectric sensor 3, thereby enabling detection of the optical fiber 5 and indirectly monitoring the operating condition of the front-end pump source.

[0036] For example, in a preferred embodiment, the photoelectric sensor 3 can be configured as a photodiode (PD). This PD has a preset alarm voltage or current threshold during detection. When the PD receives the faint light emitted by the optical fiber 5, it outputs a certain electrical signal. If the electrical signal exceeds this threshold, it can be determined whether there is a fluctuation or abnormality in the internal optical path. The alarm threshold can be set based on the required sensitivity, the expected optical signal strength, and the minimum amount of light leakage to be detected.

[0037] Of course, the determination of these detection thresholds also depends on the position of the dark box optical fiber sensor in the optical fiber path. Therefore, those skilled in the art can also know from the above examples that the dark box optical fiber sensor of the present invention can also be applied to other types of equipment using optical fiber technology.

[0038] For example, the dark box optical fiber sensor of the present invention can also be used in optical communication systems to detect whether there is a light leakage problem. For example, in an optical communication system, if the design requires that the current corresponding to the minimum optical signal intensity is 5μA, and the output current of the PD exceeds this value, then it can be considered that there is a light leakage. Or in an optical sensing system, if the set voltage threshold is 0.5V, when the voltage output by the PD exceeds 0.5V, it can also be considered as a light leakage. In addition, if the optical fiber 5 of the entire detection section does not emit light, there is no threshold, so it can be considered that there is no light. In this way, the dark box optical fiber sensor of this example can be used to detect such intermediate information and be used to judge the internal working conditions of various types of equipment.

[0039] Furthermore, in an optional embodiment, in order to more effectively transmit the reflected light to the photoelectric sensor 3 with the help of the reflection cavity 21, the reflection cavity 21 can be set to be hemispherical. Through this setting, since the detection window 11 is connected to the reflection cavity 21, and the sensing end of the photoelectric sensor 3 is facing the center of the reflection cavity 21, the reflected light can be better collected.

[0040] In addition, in order to avoid the optical fiber blocking the sensing end of the photoelectric sensor 3, as shown in FIG. Figures 5 and 6 As shown, the sensing end of the photoelectric sensor 3 is retracted into the detection window 11 to be spaced apart from the bottom opening of the detection window 11, so that the optical fiber and the sensing end of the photoelectric sensor 3 maintain a distance from each other, so that the reflected light can be refracted from the surrounding wall of the dark cavity 4 into the sensing surface of the photoelectric sensor 3, so as to better collect the reflected light.

[0041] Furthermore, in an optional embodiment, to improve the light reflection efficiency of the reflective cavity 21, the surface of the reflective cavity 21 can be mirrored. For example, the reflective cavity 21 can be mirror-finished by gold plating, polishing, or other methods. Furthermore, in another optional embodiment, the detection window 11 can also be treated in the same manner to improve the overall light reflection effect of the dark cavity 4.

[0042] On the other hand, corresponding to the above embodiments, the present invention also provides a fiber laser, which includes a seed source, a pump light source, a fiber combiner, and an optical resonant cavity connected by optical fibers, and also includes a dark box fiber sensor as described above, wherein the dark box fiber sensor is arranged on the output optical fiber of the pump light source.

[0043] Among them, in an optional embodiment, the dark box optical fiber sensor can also be respectively set on the output optical fiber of the seed source, the output optical fiber of the optical fiber combiner, the output optical fiber of the optical resonant cavity, etc., so as to collect detection data on each optical fiber transmission route of the optical fiber laser, so as to timely understand and analyze the working conditions of each device inside the optical fiber laser.

[0044] To sum up, through the dark box optical fiber sensor and its optical fiber laser provided by the utility model, a dark box structure is cleverly designed to collect the Rayleigh scattered light of the optical fiber itself in the dark cavity 4 for non-destructive detection, so there is no need to strip the optical fiber, which is convenient for setting and manual operation and avoids damage to the optical fiber. At the same time, the dark cavity 4 inside the dark box is a basically closed space, so it can have good anti-interference ability, and has a certain dust-proof and moisture-proof effect inside, thereby ensuring the high precision and accuracy of PD detection.

[0045] The preferred embodiments of the utility model disclosed above are only used to help illustrate the utility model. The preferred embodiments do not describe all the details in detail, nor do they limit the utility model to only the specific implementation methods described. Obviously, many modifications and changes can be made based on the contents of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the utility model, so that technical personnel in the relevant technical field can well understand and utilize the utility model. The utility model is only limited by the claims and their full scope and equivalents. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the utility model should be included in the scope of protection of the utility model.

[0046] In addition, the various implementations of the embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the embodiments of the present invention, they should also be regarded as the contents disclosed in the embodiments of the present invention.

Claims

1. A dark box optical fiber sensor, suitable for connecting with optical fiber, characterized in that include: A cover plate, a base, and a photoelectric sensor, wherein a detection window is provided at a first position of the base, the detection end of the photoelectric sensor is inserted into the detection window, a reflection cavity is provided in the base, and the reflection cavity is communicated with the detection window, and an optical fiber groove is provided at a second position of the base, the optical fiber groove is cut into the base body, spanning the reflection cavity and the detection window for optical fiber embedding, so that part of the optical fiber segment is suspended between the detection window and the reflection cavity, and the cover plate is connected to the base, covering the optical fiber groove on one side of the base, so that the detection window of the photoelectric sensor and the reflection cavity define a dark cavity.

2. The dark box optical fiber sensor according to claim 1, characterized in that: The reflection cavity is hemispherical.

3. The dark box optical fiber sensor according to claim 1, characterized in that: The photoelectric sensor is a photodiode.

4. The dark box optical fiber sensor according to any one of claims 1 to 3, characterized in that: The surface of the reflective cavity is mirror-shaped.

5. The dark box optical fiber sensor according to any one of claims 1 to 3, characterized in that: The sensing end of the photoelectric sensor is retracted into the detection window to be spaced apart from the bottom opening of the detection window.

6. The dark box optical fiber sensor according to claim 5, characterized in that: The inner wall surface of the dark cavity is mirror-like.

7. A fiber laser comprising a seed source, a pump light source, a fiber combiner, and an optical resonant cavity connected by optical fibers, characterized in that It also includes the dark box optical fiber sensor according to any one of claims 1 to 6, wherein the dark box optical fiber sensor is arranged on the output optical fiber of the pump light source.

8. The fiber laser according to claim 7, characterized in that The dark box optical fiber sensor is also arranged on the output optical fiber of the seed source.

9. The fiber laser according to claim 7, characterized in that The dark box optical fiber sensor is also arranged on the output optical fiber of the optical fiber combiner.

10. The fiber laser according to claim 7, characterized in that The dark box optical fiber sensor is also arranged on the output optical fiber of the optical resonant cavity.

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