Plasma laser composite deposition equipment and deposition method thereof

Abstract

The invention provides plasma laser composite deposition equipment and a deposition method thereof, and the deposition equipment comprises a laser, a lathe and a plasma emitter; the lathe is provided with a clamping assembly, and the clamping assembly is used for clamping a base rod to be deposited, so that the axis of the base rod and the axis of the clamping assembly are concentrically arranged; the laser is arranged right above the base rod and is used for emitting a laser beam to the base rod; the plasma emitter and the laser are arranged on one side of the laser at an included angle, and the plasma emitter is used for emitting SiO2 particles to the base rod; wherein SiO2 particles emitted by the plasma emitter are located in a focusing area of a laser beam emitted by the laser. The deposition equipment has the advantages of being narrow in laser heating area, small in energy needed by single-point heating, high in laser energy density, high in energy utilization rate, good in laser consistency and high in precision, and can be well suitable for efficient manufacturing of small-batch special optical fiber core rods.

Description

Technical Field

[0001] The invention relates to the technical field of optical fiber preform processing, and in particular to a plasma laser composite deposition device and a deposition method thereof. Background Art

[0002] At present, the optical fiber preform manufacturing technology mainly includes four deposition technologies: modified chemical vapor deposition (MCVD), plasma chemical vapor deposition (PCVD), external chemical deposition (OVD), and axial vapor deposition (VAD). The principle of these four technologies is to heat the target rod through hydrogen-oxygen flame or plasma, and the chemical reaction between silicon tetrachloride vapor and dopant and oxygen forms silicon dioxide and doped oxide to achieve the purpose of deposition. The existing optical fiber preform manufacturing technology has the following problems and disadvantages:

[0003] 1. High energy consumption: Because the heating range of hydrogen-oxygen flame and plasma is large, the energy diffusion is fast, the total heat required is also large, and the energy consumption is high;

[0004] 2. The process is complicated: the deposition is achieved by chemical reaction between silicon tetrachloride vapor, dopants and oxygen to form silicon dioxide and doped oxides. At the same time, the heating of the hydrogen-oxygen flame inevitably introduces hydroxyl groups, which will increase the attenuation of the optical fiber and affect the transmission performance of the optical fiber. The resulting preform also needs to be dehydroxylated.

[0005] 3. Uneven temperature in hot zone and difficult to control: The hot zone of hydrogen-oxygen flame and plasma heating is large, and there is a certain temperature difference between the inner and outer flames in the area, making it difficult to ensure the uniformity of the temperature between the inner and outer flames in the heating zone;

[0006] 4. Residual stress: Due to the uneven heating, the residual internal stress after deposition is large, which can easily cause adverse effects such as uneven wire thickness and easy breakage of the wire in the subsequent wire drawing process.

[0007] As the requirements for high-speed data transmission and low attenuation continue to increase, the demand for customized special optical fibers is also increasing; due to the above-mentioned shortcomings, the traditional optical fiber manufacturing method is more suitable for mass production of fixed types of optical fibers; and for the customization of small batches of special optical fiber core rods, technicians in this field need to find new adaptive process devices and process methods. Based on this, the present invention proposes a new film plasma laser composite deposition device and a deposition method thereof. Summary of the invention

[0008] Based on the above description, the present invention provides a plasma laser composite deposition device and a deposition method thereof to solve the technical problem in the prior art that small batches of special optical fiber core rods lack corresponding efficient and precise process deposition equipment and deposition methods.

[0009] The technical solution of the present invention to solve the above technical problems is as follows:

[0010] In a first aspect, the present invention provides a plasma laser composite deposition device, comprising: a laser, a lathe and a plasma emitter;

[0011] The lathe is provided with a clamping assembly, and the clamping assembly is used to clamp the base rod to be deposited so that the axis of the base rod is arranged concentrically with the axis of the clamping assembly;

[0012] The laser is arranged just above the base rod and is used to emit a laser beam to the base rod;

[0013] The plasma emitter is arranged at an angle with the laser on one side of the laser, and is used to emit SiO to the base rod. 2 Particles; wherein the SiO 2 The particles are located within the focal region of the laser beam emitted by the laser.

[0014] Based on the above technical solution, the present invention can also be improved as follows.

[0015] Furthermore, the plasma emitter includes: a gas mixing chamber, a plasma generator and a discharge tube;

[0016] The discharge tube is arranged through the cylindrical cavity of the plasma generator, and the outlet is arranged toward the base rod; the tail end of the gas mixing chamber is connected to the air inlet pipe, and the head end is connected to the discharge tube;

[0017] The gas mixing chamber is used to mix the reaction gas and the carrier; the plasma generator is used to ionize and excite the mixed gas to generate plasma; the discharge tube is used to ionize the SiO generated by the plasma reaction 2 Particles are projected onto the base rod.

[0018] Furthermore, the plasma emitter also includes a material delivery pipe;

[0019] The material delivery pipe is connected to the gas mixing chamber and is used for delivering reaction gas and carrier to the gas mixing chamber.

[0020] Furthermore, there are two plasma emitters;

[0021] The two plasma emitters are respectively arranged at two sides of the laser at an angle.

[0022] Furthermore, the two plasma emitters are arranged symmetrically about the central axis of the laser.

[0023] Furthermore, the laser is a CO 2 Laser.

[0024] Furthermore, the lathe is also provided with a rotating assembly;

[0025] The rotating assembly is connected to the clamping assembly and is used to drive the clamping assembly to rotate, so as to drive the base rod to perform rotational motion during the deposition process.

[0026] Furthermore, the lathe is also provided with a translation drive assembly;

[0027] The translation drive assembly is arranged on the lathe, and is used to drive the lathe to reciprocate in the horizontal direction, so as to drive the base rod to perform reciprocating translation movement during the deposition process.

[0028] In a second aspect, the present invention provides a deposition method using the plasma laser composite deposition device as described in the first aspect, comprising the following steps:

[0029] S1: Input proportional reaction gas and carrier gas into the gas mixing chamber through the raw material input pipe and mix them evenly;

[0030] S2: The mixed gas enters the plasma generator and is ionized to generate high-purity SiO 2 Particles, the high purity SiO 2 Particles enter the discharge tube;

[0031] S3: The laser emits laser light and focuses it on the surface of the base rod. At the same time, the high-purity SiO 2 The particles are ejected at a preset incident angle, and the high-purity SiO 2 When the particles pass through the laser focusing area, they absorb photon energy and are heated to melt, and are deposited on the surface of the base rod.

[0032] Based on the above technical solution, the present invention can also be improved as follows.

[0033] Furthermore, while step S3 is being performed, the following steps are also included:

[0034] The translation drive assembly drives the lathe to reciprocate in the horizontal direction, so as to drive the base rod to perform reciprocating translation motion at a preset speed; at the same time, the rotating assembly drives the clamping assembly to rotate, so as to drive the base rod to perform rotation motion at a preset speed.

[0035] Compared with the prior art, the technical solution of this application has the following beneficial technical effects:

[0036] The plasma laser composite deposition equipment provided by the present invention comprises a laser, a lathe and a plasma emitter; the lathe is provided with a clamping assembly, the clamping assembly is used to clamp a base rod to be deposited, so that the axis of the base rod is arranged concentrically with the axis of the clamping assembly; the laser is arranged directly above the base rod, and is used to emit a laser beam to the base rod; the plasma emitter is arranged at one side of the laser at an angle with the laser, and is used to emit SiO2 to the base rod. 2 Particles; wherein the SiO 2 The particles are located in the focal area of ​​the laser beam emitted by the laser. 2 The laser emits a laser beam to the corresponding area at the same time as the particles are formed, thereby depositing the melted SiO on the surface of the substrate. 2 Compared with existing methods, this scheme has the following advantages:

[0037] 1. The laser heating area is narrow, and the energy required for single-point heating is small; the laser energy density is high, and the energy utilization rate is high; the energy required is much lower than the existing four major deposition process technologies;

[0038] 2. The laser has good consistency and high precision, and can better control the manufacturing precision. The density and uniformity of the generated preform are good;

[0039] 3. The heating area corresponding to the laser focusing area is only on the surface of the base rod, and the internal stress generated by the preform rod is relatively small. Therefore, the equipment and the corresponding deposition method can be well adapted to the efficient manufacturing of small batches of special optical fiber core rods.

[0040] Since the deposition method of the plasma laser composite deposition device adopts the above-mentioned plasma laser composite deposition device, the deposition method has at least all the beneficial effects brought by the plasma laser composite deposition device, which will not be described one by one here. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic diagram of the structure of a plasma laser composite deposition device provided in an embodiment of the present invention;

[0042] Figure 2 This is a cross-sectional view of an optical fiber drawn by a laser deposition core rod manufactured according to an embodiment of the present invention under a microscope;

[0043] Figure 3 This is an output mode diagram of an optical fiber drawn by a laser deposition core rod manufactured according to an embodiment of the present invention under a thermal imager;

[0044] Figure 4 Optical imaging of the cross section of the doped coating of the optical fiber after drawing the laser deposition core rod manufactured by the embodiment of the present invention;

[0045] Figure 5The different forms of plasma flame distance under different gas flow rates;

[0046] Figure 6 A flow chart of a deposition method for performing deposition using a plasma laser composite deposition device provided in an embodiment of the present invention;

[0047] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0048] 1. Laser; 11. Laser beam;

[0049] 2. Lathe;

[0050] 3. Plasma emitter; 31. Gas mixing chamber; 32. Plasma generator; 33. Discharge tube; 34. Feed pipe;

[0051] 4. Base rod; 41. Sedimentation layer. DETAILED DESCRIPTION

[0052] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" 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, an indirect connection through an intermediate medium, or the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] The following is combined with Figures 1 to 6 The embodiments of the present invention are further described in detail with examples. The following examples are used to illustrate the present invention but cannot be used to limit the scope of the present invention.

[0055] like Figure 1 As shown, an embodiment of the present invention provides a plasma laser composite deposition device, including: a laser 1, a lathe 2 and a plasma emitter 3.

[0056] Specifically, the lathe 2 is provided with a clamping assembly, which is used to clamp the base rod to be deposited, so that the axis of the base rod 4 is arranged concentrically with the axis of the clamping assembly.

[0057] The lathe 2 is also provided with a rotating assembly and a translation driving assembly; the rotating assembly is connected to the clamping assembly and is used to drive the clamping assembly to rotate, so as to drive the base rod 4 to perform a rotational motion during the deposition process; the translation driving assembly is provided on the lathe 2 and is used to drive the lathe 2 to reciprocate in the horizontal direction, so as to drive the base rod to perform a reciprocating translational motion during the deposition process. Under the above-mentioned movement of the lathe 2, the deposition of the entire rod body can be achieved.

[0058] like Figure 1 As shown, the laser 1 is arranged directly above the base rod 4 and is used to emit a laser beam to the base rod 4.

[0059] The plasma emitter 3 is arranged at one side of the laser 1 at an angle with the laser 1 and is used to emit SiO 2 Particles; wherein the SiO emitted by the plasma emitter 3 2 The particles are located in the focal region of the laser beam emitted by the laser 1 .

[0060] In an optional embodiment, preferably, there are two plasma emitters 3; Figure 1 As shown, two plasma emitters 3 are disposed on both sides of the laser 1 at specific angles.

[0061] Further preferably, the two plasma emitters 3 are arranged symmetrically with respect to the central axis of the laser 1 .

[0062] Each plasma emitter 3 includes a gas mixing chamber 31 , a plasma generator 32 and a discharge tube 33 .

[0063] The discharge tube 33 is inserted into the cylindrical cavity of the plasma generator 32 , and the outlet is arranged toward the base rod 4 ; the tail end of the gas mixing chamber 31 is connected to the air inlet pipe, and the head end is connected to the discharge tube 33 .

[0064] The gas mixing chamber 31 is used to mix the reaction gas and the carrier; the plasma generator 32 is used to ionize and excite the mixed gas to generate plasma; the discharge tube 33 is used to ionize the SiO generated by the plasma reaction. 2 The particles (purity ≥ 99.9999%) are emitted onto the base rod.

[0065] The plasma generator 32 in this embodiment has a frequency of 2.45 GHz and a power of 6 Kw.

[0066] In addition, in order to ensure the supply of gas raw materials, the plasma emitter 3 further includes a delivery pipe 34 ; the delivery pipe 34 is connected to the gas mixing chamber 31 and is used to deliver the reaction gas and the carrier to the gas mixing chamber 31 .

[0067] It should be noted that the laser 1 is preferably a CO laser with a wavelength of 9.3 μm. 2 Laser. SiO 2The deposition efficiency of the powder depends on the thermodynamic properties of the molten zone, which is mainly related to the substrate itself, the absorbance and thermal conductivity of the laser beam, and the interaction between the powder jet and the laser beam. 2 The spectral absorption index of CO 2 Laser. After the substrate and laser are determined, the absorbance and thermal conductivity of the laser beam are also determined. The main influence is only the interaction between the powder jet and the laser beam, including absorption, reflection and scattering. 2 At the operating wavelength of the laser, SiO 2 The reflectivity is low, reflection and scattering are negligible, and the absorption between the powder jet and the laser beam becomes the main factor in the deposition process.

[0068] Absorption is mainly related to the size of powder particles, the incident angle of the conveying pipe and the conveying speed of the powder jet. The larger the powder particles, the worse the absorption rate. The size of the dust particles can be represented by x, x = πd / λ. When x < 0.1, the absorption rate is high. When x > 0.1, the absorption rate will gradually decrease. The best incident angle between the discharge tube 33 and the horizontal plane measured in the experiment is between 0 and 40°. Correspondingly, the angle between the above-mentioned discharge tube 33 and the laser 1 is preferably 50 to 90°. Preferably, the feeding speed of the conveying pipe 34 is between 0.1 and 1 g / min. Figure 5 The figure shows different forms of the plasma flame distance in the discharge tube 33 under different gas flow rates. In order to achieve the best deposition efficiency, it is preferred to Figure 5 Gas fluid in e state.

[0069] In summary, the plasma laser composite deposition device provided in the embodiment of the present invention mixes the raw material gases evenly in the gas mixing chamber 31, and the raw material gases are ionized by the plasma generator 32 to generate plasma, and the plasma reacts with each other in the discharge tube 33 to generate SiO 2 The particles are transported to the surface of the base rod through the discharge tube 33. At the same time, the laser beam emitted by the laser 1 is focused on the surface of the base rod to heat and melt SiO 2 Particles to achieve directional deposition function.

[0070] By changing the type of doping gas introduced into the feed pipe, the composition of the core rod deposition layer can be changed, and different types of doping can be achieved during deposition to produce core rods with good density and uniformity.

[0071] The relevant verification of the obtained mandrel is as follows: Figure 2 This is a cross-sectional view of the optical fiber after laser deposition core rod drawing under a microscope. Figure 3 This is the output mode diagram of the optical fiber after core rod drawing under the thermal imager. Figure 4This is the optical imaging of the cross section of the optical fiber after core rod drawing and after coating. It can be seen that good performance effects are demonstrated.

[0072] Further, in order to better explain the plasma laser composite deposition device provided by the embodiment of the present invention, the deposition method thereof is provided below:

[0073] like Figure 6 As shown, the specific deposition steps are as follows:

[0074] Step S1: Inputting a reaction gas and a carrier gas in proportion into a gas mixing chamber through a raw material input pipe and mixing them evenly;

[0075] Step S2: the mixed gas enters the plasma generator and is ionized and excited to generate plasma, and the plasma enters the discharge tube;

[0076] Step S3: The laser emits laser light and focuses it on the surface of the base rod. At the same time, the high-purity SiO generated by the plasma reaction is discharged through the discharge tube. 2 The particles are ejected at a preset incident angle, and high-purity SiO 2 When the particles pass through the laser focusing area, they absorb the photon energy and are heated to melt, and then deposited on the surface of the substrate, that is, the SiO generated by the plasma generator. 2 The particles begin to deposit when they pass through the focal area of ​​the laser beam.

[0077] While step S3 is being performed, it also includes: the translation drive component drives the lathe to reciprocate in the horizontal direction to drive the base rod to perform reciprocating translation motion at a preset speed; at the same time, the rotating component drives the clamping component to rotate to drive the base rod to perform rotational motion at a preset speed.

[0078] Specifically, various reaction gases and carrier gases are input in proportion through the feed pipe, and the various gases are evenly mixed in the gas mixing chamber and enter the plasma generator (frequency is 2.45GHz, power is 6Kw). After being ionized and excited in the plasma generator, they are ejected from the discharge tube. At this time, the raw material gases are reacted by CVD to generate high-purity SiO 2 (Purity ≥ 99.9999%) particles, the generated SiO 2 The particles (with a diameter less than 1 μm) move along the particle flow direction and are ejected through the discharge tube at a preset incident angle. At the same time, the laser emits laser light and gathers on the surface of the base rod. 2 The particles pass through the laser focus area, where the SiO 2 The particles absorb photon energy and are heated until they melt. The particles continue to move at a certain speed and begin to deposit on the surface of the base rod.

[0079] At the same time, the lathe head box performs reciprocating translational motion at a preset speed, and the chuck on the head box performs rotational motion at a preset speed, thereby realizing the deposition of the entire rod body under the movement of the lathe.

[0080] It should be noted that the preset incident angle and the preset speed are not specifically limited in this embodiment, and can be adaptively adjusted according to actual needs, which does not limit the protection scope of this application.

[0081] In summary, compared with the prior art, this embodiment can achieve the following technical effects:

[0082] 1. The laser heating area generated by the deposition equipment and the corresponding deposition method is narrow, so the energy required for single-point heating is small; the laser energy density is high and the energy utilization rate is high; the energy required is much lower than the existing four major deposition process technologies;

[0083] 2. The laser has good consistency and high precision, and can better control the manufacturing precision. The density and uniformity of the generated preform are good;

[0084] 3. The heating area corresponding to the laser focusing area is only on the surface of the base rod, and the internal stress generated by the preform rod is small. Therefore, the equipment and the corresponding deposition method can be well adapted to the efficient manufacturing of small batches of special optical fiber core rods.

[0085] In the description of this specification, the description with reference to the terms "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A plasma laser composite deposition device, characterized in that: include: Lasers, lathes and plasma emitters; The lathe is provided with a clamping assembly, and the clamping assembly is used to clamp the base rod to be deposited so that the axis of the base rod is arranged concentrically with the axis of the clamping assembly; The laser is arranged directly above the base rod and is used to emit a laser beam to the base rod; The plasma emitter is arranged at one side of the laser at an angle with the laser, and is used to emit SiO2 particles to the base rod; wherein the SiO2 particles emitted by the plasma emitter are located in the focusing area of ​​the laser beam emitted by the laser.

2. The plasma laser composite deposition equipment according to claim 1, characterized in that: The plasma emitter comprises: a gas mixing chamber, a plasma generator and a discharge tube; The discharge tube is arranged through the cylindrical cavity of the plasma generator, and the outlet is arranged toward the base rod; the tail end of the gas mixing chamber is connected to the air inlet pipe, and the head end is connected to the discharge tube; The gas mixing chamber is used for mixing the reaction gas and the carrier; the plasma generator is used for ionizing and exciting the mixed gas to generate plasma; and the discharge tube is used for emitting SiO2 particles generated by the plasma reaction onto the base rod.

3. The plasma laser composite deposition equipment according to claim 2, characterized in that: The plasma emitter also includes a material delivery pipe; The material delivery pipe is connected to the gas mixing chamber and is used for delivering reaction gas and carrier to the gas mixing chamber.

4. The plasma laser composite deposition equipment according to claim 3, characterized in that: There are two plasma emitters; The two plasma emitters are respectively arranged at two sides of the laser at an angle.

5. The plasma laser composite deposition equipment according to claim 4, characterized in that: The two plasma emitters are arranged symmetrically with respect to the central axis of the laser.

6. The plasma laser composite deposition equipment according to claim 1, characterized in that: The laser is a CO2 laser.

7. The plasma laser composite deposition equipment according to claim 1, characterized in that: The lathe is also provided with a rotating assembly; The rotating assembly is connected to the clamping assembly and is used to drive the clamping assembly to rotate, so as to drive the base rod to perform rotational motion during the deposition process.

8. The plasma laser composite deposition equipment according to claim 7, characterized in that: The lathe is also provided with a translation drive assembly; The translation drive assembly is arranged on the lathe, and is used to drive the lathe to reciprocate in the horizontal direction, so as to drive the base rod to perform reciprocating translation movement during the deposition process.

9. A deposition method using the plasma laser composite deposition device according to any one of claims 1 to 8, characterized in that: The steps include: S1: Input proportional reaction gas and carrier gas into the gas mixing chamber through the raw material input pipe and mix them evenly; S2: The mixed gas enters the plasma generator and is ionized and excited to generate plasma, and the plasma enters the discharge tube; S3: The laser emits laser light and focuses it on the surface of the base rod. At the same time, the high-purity SiO2 particles generated by the plasma reaction are ejected through the discharge tube at a preset incident angle. When the high-purity SiO2 particles pass through the laser focusing area, they absorb photon energy, are heated to melt, and are deposited on the surface of the base rod.

10. The deposition method according to claim 9, characterized in that: While step S3 is being performed, it also includes: The translation drive assembly drives the lathe to reciprocate in the horizontal direction, so as to drive the base rod to perform reciprocating translation motion at a preset speed; at the same time, the rotating assembly drives the clamping assembly to rotate, so as to drive the base rod to perform rotation motion at a preset speed.

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