Integrated fiber laser

Abstract

The utility model relates to an integrated fiber laser which comprises a seed source module, a pumping module, a light combination output module and a gain fiber. Two ends of the gain optical fiber are respectively connected with the seed source module and the light combination output module, and the light combination output module is connected with the pumping module. According to the utility model, through using three integrated modules, the whole laser only has two welding points (namely welding of two ends of the gain fiber), the number of the welding points is reduced, the probability of damage of the welding points is reduced, and the reliability is further improved. Meanwhile, the whole structure is more compact, the size of the laser is further reduced, and the manufacturing complexity of the fiber laser is reduced.

Description

Technical Field

[0001] This utility model relates to the field of lidar technology, specifically to an integrated fiber laser. Background Technology

[0002] With the continuous development of fiber laser technology, its application fields are becoming increasingly wider, especially in the field of lidar technology in recent years. At present, lidar has increasingly smaller requirements for the size of fiber lasers. The fiber lasers used in lidar light sources usually integrate some passive optical components into one device, thereby reducing fiber fusion splices. Other components, such as seed sources, pump sources, and active fibers, are connected together by fiber fusion splicing, reducing the number of passive components and the size, while improving the reliability of fiber lasers. However, problems such as large size and many fiber connection points still exist, resulting in high manufacturing costs for mass production. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide an integrated fiber laser.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] An integrated fiber laser includes a seed source module, a pump module, a beam combining output module, and a gain fiber;

[0006] The two ends of the gain fiber are connected to the seed source module and the light combining output module, respectively, and the light combining output module is connected to the pump module.

[0007] The seed source module includes a first housing and a seed source, a first isolator, and a first fiber collimator fixed inside the first housing; the seed source is used to emit collimated signal light, the first isolator is used to allow the signal light to pass unidirectionally and isolate the backward light, and the first fiber collimator is used to couple the signal light passing through the first isolator to the gain fiber; the first housing is a sealed structure.

[0008] The pump module includes a second housing and a pump source, a collimating lens, and a first window fixed inside the second housing; the pump source is used to emit pump light, the collimating lens is used to collimate the pump light, the first window is used to transmit the pump light, and the second housing is a sealed structure.

[0009] The gain fiber is used to absorb pump light and amplify signal light;

[0010] The combined light output module includes a third housing and a second fiber collimator, a dichroic mirror, a second isolator, a third fiber collimator, and a second window fixed within the third housing. The dichroic mirror is used to transmit amplified signal light and reflect pump light. The second fiber collimator is used to collimate the amplified signal light to the dichroic mirror and couple the pump light to the gain fiber. The second isolator is used to allow the amplified signal light to pass unidirectionally and isolate the backward light. The third fiber collimator is used to couple the amplified signal light for output. The second window is positioned opposite to the first window and is used to transmit pump light from the pump module. The third housing is a sealed structure.

[0011] Furthermore, the dichroic mirror that transmits the signal light and reflects the pump light is replaced with a dichroic mirror that transmits the pump light and reflects the signal light.

[0012] Furthermore, the light combining output module has one or more reflective mirrors or reflective prisms inside, which are used to deflect the optical path of the pump light or signal light.

[0013] Furthermore, each of the combined light output modules is internally equipped with a beam splitting device to split the amplified signal light into a main signal light and a monitoring light. At the same time, the third fiber collimator is configured as a dual fiber collimator or two single fiber collimators to output the main signal light and the monitoring light.

[0014] Furthermore, the collimating lens is composed of one or more lenses, which are spherical, aspherical, or cylindrical.

[0015] Furthermore, the first isolator and the second isolator are single-stage or multi-stage isolators.

[0016] Furthermore, the first shell, the second shell, and the third shell are made of glass, metal, or ceramic, and their shapes are cuboids or cylinders.

[0017] Furthermore, the gain fiber is a single-clad or double-clad fiber.

[0018] The present invention, employing the above technical solution, has the following beneficial effects: by using three integrated modules, the entire laser has only two splice points (i.e., the splices at both ends of the gain fiber), reducing the number of splice points, lowering the probability of splice damage, and further improving reliability. Simultaneously, the overall structure is more compact, further reducing the size of the laser and lowering the complexity of fiber laser manufacturing. Attached Figure Description

[0019] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0020] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present utility model;

[0021] Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0022] Figure 3 This is a schematic diagram of the structure of Embodiment 3 of this utility model;

[0023] Figure 4 This is a schematic diagram of the structure of Embodiment 4 of this utility model;

[0024] Figure 5 This is a schematic diagram of the structure of Embodiment 5 of the present invention;

[0025] Figure 6 This is a structural schematic diagram of Embodiment 6 of the present invention. Detailed Implementation Example 1

[0026] Figure 1 This is a schematic diagram of an integrated fiber laser according to Embodiment 1 of the present invention. Embodiment 1 includes a seed source module 1, a gain fiber 2, a beam combining output module 3, and a pump module 4. The two ends of the gain fiber 2 are connected to the seed source module 1 and the beam combining output module 3, respectively. The beam combining output module 3 is connected to the pump module 4.

[0027] The seed source module 1 includes a first housing 103 with a sealed structure, and a seed source 101, a first isolator 102 and a first fiber collimator 104 fixed inside the first housing 103. The seed source 101 is used to emit collimated signal light, the first isolator 102 is used to allow the signal light to pass through unidirectionally and isolate the backward light, and the first fiber collimator 104 is used to couple the signal light passing through the first isolator to the gain fiber 2.

[0028] The pump module 4 includes a sealed second housing 404 and a pump source 401, a collimating lens 402, and a first window 403 fixed within the second housing 404. The pump source 401 is used to emit pump light, the collimating lens 402 is used to collimate the pump light, and the first window 403 is used to transmit the pump light.

[0029] The optical output module 3 includes a sealed third housing 304 and a second fiber collimator 301, a dichroic mirror 302, a second isolator 303, a third fiber collimator 305, and a second window 306 fixed within the third housing 304. The dichroic mirror 302 is used to transmit amplified signal light and reflect pump light. The second fiber collimator 301 is used to collimate the amplified signal light to the dichroic mirror 302 and couple the pump light to the gain fiber 2. The second isolator 303 is used to allow the amplified signal light to pass unidirectionally and isolate the backward light. The third fiber collimator 305 is used to couple the amplified signal light to the output. The second window 306 is positioned opposite to the first window 403 and is used to transmit pump light from the pump module.

[0030] The first shell 103, the second shell 404, and the third shell 304 are made of glass, metal, or ceramic, and the first shell 103, the second shell 404, and the third shell 304 are in the shape of a cuboid, a cylinder, or any other regular or irregular shape.

[0031] The first isolator 102 and the second isolator 303 are single-stage or multi-stage isolators.

[0032] Seed source 1 is in TO package and emits signal light with a wavelength of 1535nm. After passing through the first isolator 102, it is coupled into the gain fiber 2 by the first fiber collimator 104.

[0033] The gain fiber 2 is connected to the first fiber collimator 104 and the second fiber collimator 301 to absorb pump light and amplify signal light.

[0034] Pump source 401 emits pump light with a wavelength of 900nm~1000nm. Collimating lens 402 is composed of one or more lenses, which are spherical, aspherical or cylindrical. After being collimated by collimating lens 402, the pump light passes through the first window 403 and enters the beam combining output module 3.

[0035] The pump light entering the beam combiner output module 3 is reflected by the dichroic mirror 302 and then coupled into the gain fiber 2 by the second fiber collimator 302.

[0036] The gain fiber 7 is an erbium-ytterbium co-doped double-clad fiber, coiled on the outside, which absorbs pump light and amplifies signal light. The amplified signal light passes through the second fiber collimator 302 and then through the dichroic mirror 302 and the second isolator 303 in sequence. Finally, the amplified signal light is output from the fiber of the third fiber collimator 305. Example 2

[0037] Figure 2This is a schematic diagram of Embodiment 2 of the present invention. The difference from Embodiment 1 is that the third fiber collimator 305 is replaced by a dual-fiber collimator 307 in the light combining output module 3, and a beam splitter 308 is added to the light combining output module. The beam splitter 308 is disposed between the second isolator 303 and the dual-fiber collimator 307, and is used to split the amplified signal light after passing through the second isolator 303 into a main signal light and a monitoring light. Finally, the main signal light and the monitoring light are output from the two optical fibers of the dual-fiber collimator 307, respectively. The rest is the same as in Embodiment 1, and will not be described again here. Example 3

[0038] Figure 3 This is a schematic diagram of Embodiment 3 of the present invention. The difference from Embodiment 1 is that the light combining output module 3 uses a dichroic mirror 309 that transmits pump light and reflects signal light instead of a dichroic mirror 302 that transmits signal light and reflects pump light, that is, the transmission directions of pump light and amplified signal light are reversed. The rest are the same as in Embodiment 1, and will not be described again here. Example 4

[0039] Figure 4 This is a schematic diagram of Embodiment 4 of the present invention. The difference from Embodiment 3 is that the third fiber collimator 305 is replaced by a dual-fiber collimator 310 in the light combining output module 3, and a beam splitter 310 is added to the light combining output module. The beam splitter 310 is located between the second isolator 303 and the dual-fiber collimator 11, and is used to split the amplified signal light after passing through the second isolator 303 into a main signal light and a monitoring light. Finally, the main signal light and the monitoring light are output from the two optical fibers of the dual-fiber collimator 307, respectively. The rest is the same as in Embodiment 3, and will not be described again here. Example 5

[0040] Figure 5 This is a schematic diagram of the structure of Embodiment 5 of this utility model. The difference from Embodiment 3 is that a reflecting prism 312 is provided between the dichroic mirror 309 and the second isolator 303 in the light combining output module 3. The reflecting prism 312 is used to reflect the amplified signal light, that is, to deflect the optical path of the signal light. The rest are the same as in Embodiment 3, and will not be described again here. Example 6

[0041] Figure 6This is a schematic diagram of the structure of Embodiment 6 of the present invention. The difference from Embodiment 5 is that the third fiber collimator 305 is replaced by a dual-fiber collimator 314 in the light combining output module 3, and a beam splitter 313 is added to the light combining output module. The beam splitter 313 is disposed between the second isolator 303 and the dual-fiber collimator 314, and is used to split the amplified signal light after passing through the second isolator 303 into a main signal light and a monitoring light. Finally, the main signal light and the monitoring light are output from the two optical fibers of the dual-fiber collimator 314, respectively. The rest is the same as in Embodiment 5, and will not be described again here.

[0042] The specific embodiments of this utility model have been described above. However, those skilled in the art should understand that this is only an example. Those skilled in the art can make various changes or modifications to this embodiment without departing from the principle and essence of this utility model, but all such changes and modifications fall within the protection scope of this utility model.

Claims

1. An integrated fiber laser, characterized by: The seed source module, the pumping module, the light combination output module and the gain fiber are included. Two ends of the gain fiber are connected with the seed source module and the light combination output module respectively, and the light combination output module is connected with the pumping module. The seed source module includes a first shell, a seed source, a first isolator and a first fiber collimator fixed in the first shell; the seed source is used for emitting collimated signal light; the first isolator is used for passing the signal light in one direction and isolating backward light; the first fiber collimator is used for coupling the signal light passing through the first isolator to the gain fiber; and the first shell is a sealed structure. The pumping module includes a second shell, a pumping source, a collimating lens and a first window piece fixed in the second shell; the pumping source is used for emitting pumping light; the collimating lens is used for collimating the pumping light; and the first window piece is used for transmitting the pumping light; and the second shell is a sealed structure. The gain fiber is used for absorbing the pumping light and amplifying the signal light. The light combination output module includes a third shell, a second fiber collimator, a dichroic mirror, a second isolator, a third fiber collimator and a second window piece fixed in the third shell; the dichroic mirror is used for transmitting the amplified signal light and reflecting the pumping light; the second fiber collimator is used for collimating the amplified signal light to the dichroic mirror and coupling the pumping light to the gain fiber; the second isolator is used for passing the amplified signal light in one direction and isolating backward light; the third fiber collimator is used for coupling the amplified signal light to be output; and the second window piece is opposite to the first window piece in position and is used for transmitting the pumping light from the pumping module; and the third shell is a sealed structure.

2. The integrated fiber laser of claim 1, wherein: The dichroic mirror transmitting the signal light and reflecting the pumping light is replaced by a dichroic mirror transmitting the pumping light and reflecting the signal light.

3. The integrated fiber laser of claim 1, wherein: The light combination output module is internally provided with one or more than two mirrors or reflecting prisms for turning the light path of the pumping light or the signal light.

4. The integrated fiber laser of claim 1, wherein: The light combination output module is internally provided with a light splitting device for splitting the amplified signal light into main signal light and monitoring light, and the third fiber collimator is provided as a double fiber collimator or two single fiber collimators for outputting the main signal light and the monitoring light.

5. The integrated fiber laser of claim 1, wherein: The collimating lens is composed of one or more than two lenses, and the lenses are spherical or aspherical or cylindrical.

6. The integrated fiber laser of claim 1, wherein: The first isolator and the second isolator are single-stage or multi-stage isolators.

7. The integrated fiber laser of claim 1, wherein: The materials of the first shell, the second shell and the third shell are glass, metal or ceramic, and the shapes of the first shell, the second shell and the third shell are cuboid or cylinder.

8. The integrated fiber laser of claim 1, wherein: The gain fiber is a single-clad or double-clad fiber.

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