CN102496840B - Miniature optical-fiber loop narrow-line and wide-optical-fiber laser - Google Patents

Abstract

A micro-fiber loop narrow-linewidth fiber laser relates to a laser, which solves the problems of complex structure, poor stability, and poor ability to adjust the linewidth and wavelength of an output laser signal in current narrow-linewidth fiber lasers. In the laser, a pumping source (4), a first fiber grating (21), an active single-mode fiber (1), a miniature fiber loop (3) and a second fiber grating (22) are connected in sequence. Micro-optical fiber loop (3) After removing the coating from the ordinary single-mode optical fiber, heat and draw in the middle of N optical fibers to form six micro-fiber optical fibers with a diameter of 5-15 microns in the middle, and keep the original parameters of the optical fibers at both ends unchanged. The root diameter is drawn to 5-15 microns, and the micro-fibers are cross-arranged to form a triangle, rectangle, grid or tetrahedron, and are made by heating and welding at their intersections, or any two micro-fiber ends are connected together. It is made until only two tiny optical fiber ends are left. Applicable to the field of optical fiber communication.

Description

Miniature Fiber Loop Narrow Linewidth Fiber Laser

technical field

The invention relates to a laser, which is suitable for the field of optical fiber communication.

Background technique

At present, among all kinds of lasers, the advantages of fiber lasers are the most eye-catching. Fiber lasers have good beam quality, compact structure, low thermal efficiency, and high light-to-light conversion efficiency. Therefore, fiber lasers have been well promoted in many fields. As far as the current development situation is concerned, fiber lasers mainly have several development directions such as multi-wavelength, narrow linewidth and high power.

First of all, in terms of high-power fiber lasers, fiber lasers based on cladding pumping technology have attracted widespread attention for their good beam quality, high conversion efficiency, and compact structure. In 2004, the single-fiber output power of fiber lasers reached the kilowatt level. In 2009, IPG reported that it had achieved a single-fiber 10,000-watt single-mode laser output. However, as the power increases, various nonlinear effects such as SBS, SRS, and FWM seriously degrade the beam quality and become a huge obstacle to further increase the laser power. The proposal of large mode area LMA fiber has become a feasible method. In the case of keeping the optical power density constant, increasing the fiber radius can effectively increase the optical power that the fiber can carry, which provides a great opportunity for the preparation of high-power fiber lasers. necessary prerequisite. However, due to the limited increase in fiber radius, too large fiber radius makes the mode field complex and the beam quality cannot be guaranteed. Therefore, the problem that this method can solve is limited by the size of the fiber.

Another method is the power amplifier MOPA of the main control oscillator. This method can effectively increase the laser power, and the quality of the output laser is very high, but it is also limited by the optical power carrying capacity of a single fiber.

Secondly, in terms of narrow line width, fiber lasers are mainly miniaturized, and more are pursuing narrower line widths. There are many additional devices and equipment, which makes the structure of the laser complex and unreliable.

Therefore, the current narrow-linewidth fiber laser has complex structure, poor stability, and poor ability to adjust the linewidth and wavelength of the output laser signal.

Contents of the invention

The technical problem to be solved by this invention is:

At present, narrow-linewidth fiber lasers have complex structures, poor stability, and poor ability to adjust the linewidth and wavelength of output laser signals.

Technical scheme of the present invention is:

A miniature fiber loop narrow-linewidth fiber laser, which includes an active single-mode fiber, a first fiber grating, a second fiber grating, a miniature fiber loop and a pumping source, is characterized in that:

After removing the coating from the ordinary single-mode optical fiber, the miniature optical fiber ring is heated and drawn in the middle of N optical fibers to form N micro optical fibers with a diameter of 5-15 microns in the middle, and the parameters of the optical fibers at both ends remain unchanged. The fine optical fibers drawn to a diameter of 5-15 microns are cross-arranged to form triangles, rectangles, grids or tetrahedrons, and are heated and welded at their intersections; or the diameters of N roots are drawn to 5-15 microns The micro-fibers are cross-arranged to form a triangle, rectangle, grid or tetrahedron, and are heated and fused at their intersections to connect any two micro-fiber ends until only two micro-fiber ends are left;

N=3, 4, 6;

The connection mode between the components constituting the narrow linewidth fiber laser is:

The output end of the pump source is connected to one end of the first fiber grating, the other end of the first fiber grating is connected to one end of the active single-mode fiber, and the other end of the active single-mode fiber is connected to any microfiber that forms a micro-fiber loop. One end of the fiber grating is connected, and the other end of any micro-fiber that constitutes the micro fiber loop is connected to one end of the second fiber grating; the laser is output from the other end of the second fiber grating;

When any two tiny fiber ends are connected in the miniature fiber loop until only two tiny fiber ends are left, the connection mode between the components constituting the narrow linewidth fiber laser is:

The output end of the pump source is connected to one end of the first fiber grating, the other end of the first fiber grating is connected to one end of the active single-mode fiber, and the other end of the active single-mode fiber is connected to the remaining two ends of the micro-fiber loop. One of the two tiny fiber ends is connected, and the other of the two tiny fiber ends left in the micro fiber loop is connected to one end of the second fiber grating; the laser is output from the other end of the second fiber grating.

The miniature optical fiber loop is formed of three tiny optical fibers crossed in pairs to form a triangular loop at the center.

The miniature optical fiber loop is a loop in which four tiny optical fibers are cross-arranged to form a rectangle at the center, and any two ends are connected until only two optical fiber ends are left.

The miniature optical fiber loop is formed by crossing six tiny optical fibers to form a grid-shaped loop at the center, connecting any two ends until only two optical fiber ends are left.

The said miniature optical fiber loop is a tetrahedron-shaped loop in the center formed by crossing six tiny optical fibers with three intersection points.

The core of the active single-mode optical fiber is doped with rare earth ions, including erbium ions, ytterbium ions, neodymium ions, thulium ions or holmium ions.

The distance between any two welding points in the miniature optical fiber loop is 10-1000 microns.

Compared with the prior art, the present invention has the following beneficial effects:

The manufacturing method of the miniature optical fiber loop described in the present invention is much less difficult than that of the annular microring, because the process of winding into a ring is very easy to cause when the diameter of the optical fiber is drawn to a scale of several microns. The breakage of the optical fiber, and the miniature optical fiber loop described in the present invention is to arrange the micro-fibers crosswise, and then weld them at the intersection points, without bending the optical fibers, avoiding the breakage of the optical fibers due to bending, and has a simple structure. Greatly increased the success rate of production. The prepared miniature optical fiber loop has strong stability and stable filtering characteristics. The shape and size of the miniature optical fiber loop and the connection mode of the optical fiber end can be freely set to meet the selection requirements of the wavelength, and the adjustability is strong.

Description of drawings

Figure 1 shows a narrow linewidth fiber laser with a triangular shape in the miniature fiber loop.

Figure 2 shows a narrow linewidth fiber laser with a rectangular microfiber loop.

Figure 3 shows a narrow linewidth fiber laser with a rectangular microfiber loop.

Figure 4 shows a narrow linewidth fiber laser with a microfiber loop in the form of a grid.

Figure 5 shows a narrow linewidth fiber laser with a tetrahedral microfiber loop.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings.

Implementation Mode 1

A miniature fiber loop narrow-linewidth fiber laser, as shown in FIG.

The micro-optical fiber loop 3 is removed from the coating of the ordinary single-mode optical fiber, heated and drawn in the middle of the three optical fibers to form three micro-fibers with a diameter of 5 microns in the middle, and the parameters of the optical fibers at both ends remain unchanged. The tiny optical fibers drawn to 5 microns are crossed and arranged to form a triangle, and are heated and fused at their intersections.

The connection mode between the components constituting the narrow linewidth fiber laser is:

The output end of the pump source 4 is connected to one end of the first fiber grating 21, the other end of the first fiber grating 21 is connected to one end of the active single-mode optical fiber 1, and the other end of the active single-mode optical fiber 1 is connected to the miniature optical fiber loop One end of any fine fiber of 3 is connected, and another end of any fine fiber constituting the micro fiber loop 3 is connected with one end of the second fiber grating 22; the laser is output from the other end of the second fiber grating 22.

The rare earth ions doped in the core of the active single-mode optical fiber 1 are erbium ions.

The distance between any two fusion points in the miniature optical fiber loop 3 is 10 microns.

Implementation Mode Two

A miniature fiber loop narrow-linewidth fiber laser, as shown in FIG.

After the described miniature optical fiber loop 3 is removed from the coating by the common single-mode optical fiber, it is heated and drawn in the middle of the four optical fibers to form four micro optical fibers with a diameter of 15 microns in the middle, and the parameters of the optical fibers at both ends keep the original parameters unchanged. The tiny optical fibers drawn to a diameter of 15 microns are cross-arranged to form a rectangle, heated and fused at their intersections, and then the end-to-end connections of each of the three fibers are made.

The connection mode between the components constituting the narrow linewidth fiber laser is:

The output end of the pump source 4 is connected to one end of the first fiber grating 21, the other end of the first fiber grating 21 is connected to one end of the active single-mode optical fiber 1, and the other end of the active single-mode optical fiber 1 is connected to the miniature optical fiber loop 3. Only one of the two remaining micro-fiber ends is connected, and the other of the two remaining micro-fiber ends is connected to an end of the second fiber grating 22 in the micro-fiber loop circuit; 22 output at the other end.

The rare earth ions doped in the core of the active single-mode optical fiber 1 are ytterbium ions.

The distance between any two fusion points in the miniature optical fiber loop 3 is 1000 micrometers, and the length of the connection line between any two tail ends is 10-30 cm.

Implementation Mode Three

A miniature fiber loop narrow-linewidth fiber laser, as shown in FIG.

After the described miniature optical fiber loop 3 is removed from the coating by the common single-mode optical fiber, it is heated and drawn in the middle of the four optical fibers to form four micro optical fibers with a diameter of 15 microns in the middle, and the parameters of the optical fibers at both ends keep the original parameters unchanged. The micro-fibers with a root diameter drawn to 15 microns are cross-arranged to form a rectangle, heated and fused at their intersections, and then any two ends are connected until only two optical fiber ends are left.

The connection mode between the components constituting the narrow linewidth fiber laser is:

The output end of the pumping source 4 is connected to one end of the first fiber grating 21, the other end of the first fiber grating 21 is connected to one end of the active single-mode optical fiber 1, and the other end of the active single-mode optical fiber 1 is connected to the miniature optical fiber loop 3. Only one of the two remaining micro-fiber ends is connected, and the other of the two remaining micro-fiber ends of the micro-fiber loop 3 is connected to an end of the second fiber grating 22; the laser light from the second fiber grating 22 output at the other end.

The rare earth ions doped in the core of the active single-mode optical fiber 1 are neodymium ions.

The distance between any two fusion splicing points in the miniature optical fiber loop 3 is 1000 microns, and the length of the connection line between any two tail ends is 20-40 cm.

Implementation Mode Four

A miniature fiber loop narrow-linewidth fiber laser, as shown in FIG.

The micro-optical fiber loop 3 is removed from the coating of the ordinary single-mode optical fiber, heated and drawn in the middle of the six optical fibers to form six micro-fibers with a diameter of 7 microns in the middle, and the parameters of the optical fibers at both ends remain unchanged. The micro-fibers drawn to 7 microns are cross-arranged to form a grid shape, heated and fused at their intersections, and then any two ends are connected until only two optical fiber ends are left.

The connection mode between the components constituting the narrow linewidth fiber laser is:

The output end of the pumping source 4 is connected to one end of the first fiber grating 21, the other end of the first fiber grating 21 is connected to one end of the active single-mode optical fiber 1, and the other end of the active single-mode optical fiber 1 is connected to the miniature optical fiber loop 3. Only one of the two remaining micro-fiber ends is connected, and the other of the two remaining micro-fiber ends of the micro-fiber loop 3 is connected to an end of the second fiber grating 22; the laser light from the second fiber grating 22 output at the other end.

The micro-optical fiber loop 3 is a grid-shaped loop with six micro-optical fibers cross-arranged in the center.

The core of the active single-mode optical fiber 1 is doped with rare earth ions as thulium ions.

The distance between any two fusion splicing points in the miniature optical fiber loop 3 is 60 microns, and the length of the connection line between any two tail ends is 20-40 cm.

Implementation Mode Five

A miniature fiber loop narrow-linewidth fiber laser, as shown in FIG.

The micro-optical fiber loop 3 is removed from the coating of the ordinary single-mode optical fiber, heated and drawn in the middle of the six optical fibers to form six micro-fibers with a diameter of 5 microns in the middle, and the parameters of the optical fibers at both ends remain unchanged. The tiny optical fibers drawn to 5 microns are cross-arranged to form a tetrahedron, and are heated and fused at their intersections.

The connection mode between the components constituting the narrow linewidth fiber laser is:

The output end of the pump source 4 is connected to one end of the first fiber grating 21, the other end of the first fiber grating 21 is connected to one end of the active single-mode optical fiber 1, and the other end of the active single-mode optical fiber 1 is connected to the miniature optical fiber loop One end of any microfiber of 3 is connected, and another end of any microfiber of microfiber loop 3 is connected with one end of the second fiber grating 22; the laser is output from the other end of the second fiber grating 22.

The micro-optical fiber loop 3 is a tetrahedron-shaped loop at the center formed by crossing six micro-fibers with three intersection points.

The core of the active single-mode optical fiber 1 is doped with holmium ions as rare earth ions.

The distance between any two fusion points in the miniature optical fiber loop 3 is 200 micrometers, and the length of the connection line between any two tail ends is 20-40 cm.

Claims (7)

1. Miniature optical-fiber loop narrow, this laser comprises active monomode fiber (1), the first fiber grating (21), the second fiber grating (22), mini optical fibre loop (3) and pumping source (4), it is characterized in that:

Described mini optical fibre loop (3) is removed after the coating by general single mode fiber, being drawn into the middle part diameter in the heating of N root optical fiber middle part is 5～15 microns, the two ends optical fiber parameter keeps the constant fine optical fiber of N root of raw parameter, N root diameter is drawn to 5～15 microns fine optical fiber cross arrangement formation triangle, rectangle, grid-shaped or tetrahedroid, makes in its infall heat welded; Or N root diameter is drawn to 5～15 microns fine optical fiber cross arrangement forms triangle, rectangle, grid-shaped or tetrahedroid, in its infall heat welded, any two fine optic fibre ends are coupled together, make until only stay two fine optic fibre ends;

N?=?3、4、6；

When mini optical fibre loop (3) is N root diameter to be drawn to 5～15 microns fine optical fiber cross arrangement formation triangle, rectangle, grid-shaped or tetrahedroid, when its infall heat welded was made, the connected mode that consists of between each device of this narrow cable and wide optical fiber laser was:

The output of pumping source (4) is connected with an end of the first fiber grating (21), the other end of the first fiber grating (21) is connected with an end of active monomode fiber (1), the other end of active monomode fiber (1) is connected with a termination of any fine optical fiber that consists of mini optical fibre loop (3), and an other termination that consists of any fine optical fiber of mini optical fibre loop (3) is connected with an end of the second fiber grating (22); Laser is from the other end output of the second fiber grating (22);

Any two fine optic fibre ends are coupled together in the mini optical fibre loop (3), until when only staying the situation of two fine optic fibre ends, the connected mode that consists of between each device of this narrow cable and wide optical fiber laser is:

The output of pumping source (4) is connected with an end of the first fiber grating (21), the other end of the first fiber grating (21) is connected with an end of active monomode fiber (1), one of them of two fine optic fibre ends that the other end of active monomode fiber (1) and mini optical fibre loop (3) only stay is connected, and another of two fine optic fibre ends that mini optical fibre loop (3) only stays is connected with an end of the second fiber grating (22); Laser is from the other end output of the second fiber grating (22).

2. Miniature optical-fiber loop narrow according to claim 1 is characterised in that:

Described mini optical fibre loop (3) is that to become the center by three in twos cross arrangements of fine optical fiber be triangular loop.

3. Miniature optical-fiber loop narrow according to claim 1 is characterised in that:

Described mini optical fibre loop (3) is that to become the center by four fine optical fiber cross arrangements be rectangle, any two terminations is coupled together, until only stay the loop of two optic fibre ends.

4. Miniature optical-fiber loop narrow according to claim 1 is characterised in that:

Described mini optical fibre loop (3) is that to become the center by the fine optical fiber cross arrangement of the six roots of sensation be the grid-shaped loop, any two terminations is coupled together, until only stay the loop of two optic fibre ends.

5. Miniature optical-fiber loop narrow according to claim 1 is characterised in that:

Described mini optical fibre loop (3) is that to become the center be the tetrahedroid loop to the cross arrangement by per three intersection points of the fine optical fiber of the six roots of sensation.

6. Miniature optical-fiber loop narrow according to claim 1 is characterized in that:

Doping with rare-earth ions in the fibre core of active monomode fiber (1) comprises erbium ion, ytterbium ion, neodymium ion, thulium ion or holmium ion.

7. Miniature optical-fiber loop narrow according to claim 1 is characterized in that:

The distance of any two fusion points is 10～1000 microns in the described mini optical fibre loop (3).

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