CN112077705B

CN112077705B - APC grinding process and structure of mini type MT ferrule

Info

Publication number: CN112077705B
Application number: CN202010989927.8A
Authority: CN
Inventors: 欧阳艳; 郑钟信; 陈斌
Original assignee: Time Interconnect Technology Huizhou Ltd
Current assignee: Time Interconnect Technology Huizhou Ltd
Priority date: 2020-09-18
Filing date: 2020-09-18
Publication date: 2022-04-12
Anticipated expiration: 2040-09-18
Also published as: CN112077705A

Abstract

The application relates to an APC grinding process and structure of a mini type MT ferrule, which comprises the following steps: s1, penetrating fibers and curing; s2, grinding and pretreating; s3, coarse grinding; s4, polishing; s5, drawing fibers; s6, polishing; and S7, cleaning and checking. The beneficial effect of this application is: this application adopts the grinding technology, and the effectual mini lock pin APC that has solved grinds the damaged, terminal surface of lock pin bad, the high bad problem of lock pin passageway optic fibre. And more than 16 inserting cores can be ground simultaneously, and the machining efficiency of the inserting cores is greatly improved. The utility model provides a Mini type MT lock pin APC inclination structure can effectual improvement lock pin return loss numerical value, and the performance is better.

Description

APC grinding process and structure of mini type MT ferrule

Technical Field

The application relates to the technical field of multi-channel ferrule processing technologies, in particular to an APC grinding technology and structure of a mini type MT ferrule.

Background

With the comprehensive coverage of the 4G technology and the large-area popularization of the 5G technology, and the rapid development of technologies such as data center interconnection, optical fiber sensing, new-generation optical fibers and the like, an optical transmission network with ultra-large capacity, ultra-high speed and ultra-long distance will become a necessary condition for the construction of the 5G data center, and equipment assembly equipment for a bearing optical module gradually develops towards miniaturization and densification. The requirements for the densification, miniaturization and simplification of the optical fiber assembly are higher.

The mini MT insertion core is an important core of multichannel data transmission equipment, the volume of the mini MT insertion core is smaller than that of a common MT insertion core by more than 50%, and the mini MT insertion core is more matched with an equipment assembly of a miniaturized and intensive optical module. However, due to its small size and thin wall thickness, the processing difficulty is the grinding-polishing equipment and process. How to effectively fix the mini type MT insertion core and carry out the end face grinding and polishing process not only relates to the improvement of mechanical equipment, but also needs to accurately control the pressure, the rotating speed, the time and the like involved in the grinding process.

The existing mini type MT insertion core processing technology is limited by technology, and only one type of Physical Contact (PC) connector is applied in a large scale at present, the optical fibers at two ends of the PC connector are in direct contact, the insertion return loss value can only meet the conditions that IL is less than or equal to 0.7dB and RL is greater than or equal to 25 dB. However, with the current trend of 5G large area coverage, the high power lasers used in long haul fiber links are very sensitive to reflections, which can even be damaged by severe reflections. An inclined Physical Contact (APC) type structure is a product structure which is most suitable for large-area popularization and effectively solves the problem of low return loss in the prior art.

Disclosure of Invention

The application aims to solve the problems of low return loss and unstable APC (automatic Power control) processing technology of a PC (personal computer) type mini-type MT (MT) ferrule in the prior art, and the technical problem to be solved by the application is to provide an APC grinding technology and structure of the mini-type MT ferrule.

An APC grinding process of a mini type MT ferrule comprises the following steps:

s1: fiber penetration and solidification: a plurality of optical fibers are penetrated into the optical fiber channel hole of the mini type MT insertion core; injecting glue into a glue injection window of the mini ferrule, and baking the mini MT ferrule at high temperature;

s2: grinding pretreatment: cutting off the optical fiber exposed out of the mini type MT insertion core end face, and fixing the optical fiber in a grinding disc, wherein the grinding disc is placed in a matching way with a grinding device;

s3, coarse grinding: the grinding device selects grinding sand paper with abrasive particle size of 16um, and grinds the end face of the ferrule under the requirements of coarse grinding rotation speed and coarse grinding pressure, wherein the grinding time is 20-40 s;

s4, polishing: the grinding device selects grinding abrasive paper with the grain size of 3 microns, and grinds the end face of the ferrule under the polishing rotation speed and the polishing pressure for 60-100 s;

s5, fiber drawing: the grinding device selects grinding abrasive paper with abrasive particle size of 1um, and grinding liquid is attached to the grinding paper, the grinding device grinds the end face of the ferrule under the fiber drawing rotating speed and the fiber drawing pressure, and the grinding fiber drawing time is 95-120 s;

s6, polishing: the grinding device selects grinding abrasive paper with abrasive particles of 0.5um, grinds the end face of the ferrule under the conditions of polishing rotation speed and polishing pressure, and the grinding fiber drawing time is 70-110 s;

s7: cleaning and checking: and cleaning the end face of the inserting core and detecting the performance.

In the step S3, abrasive paper with abrasive grains of 16um is selected, the polishing apparatus is rotated at a coarse polishing speed of 70rmp to 90rmp, the coarse polishing pressure of the polishing apparatus is carried out under a load of 3.0kg to 4kg, and the polishing time is 20S to 40S.

In the step S3, the polishing paper material is silicon carbide polishing paper.

In the step S4, a polishing sand paper having a particle size of 3um is selected, the polishing device is rotated at a polishing rotational speed of 110rmp to 130rmp, the polishing pressure of the polishing device is carried out under a load of 5.5kg to 8kg, and the polishing time is 70S to 95S.

In the step S4, the polishing paper material is silicon carbide polishing paper.

In the step S5, a polishing abrasive paper with abrasive grains of 1um in diameter is selected, and a polishing liquid is attached to the polishing paper, the polishing apparatus is rotated at a fiber drawing speed of 130rmp to 155rmp, the fiber drawing pressure of the polishing apparatus is performed under a load of 6kg to 8.5kg, and the polishing time is 100S to 130S.

In the step S5, the grinding paper is made of a PEI film adhesive paper coated with a polyester fiber coating layer; the grinding fluid is cerium oxide grinding fluid.

In the step S7, abrasive paper with abrasive grains of 0.5um is selected, the grinding device rotates at a polishing speed of 130 rmp-160 rmp, the polishing pressure of the grinding device is carried out under the load of 6 kg-8.5 kg, and the grinding time is 70S-90S; the polishing times are not less than once.

In the step S7, the grinding paper is made of a PEI film adhesive paper coated with a polyester fiber coating layer.

A mini type MT insertion core APC structure comprises the grinding process of the mini type MT insertion core, wherein one end of the end face of the insertion core is a horizontal step face, and the other end of the end face of the insertion core is an inclined end face; the angle alpha of the inclined end face is 5-10 degrees.

Compared with the prior art, the beneficial effects of this application are: the method adopts a grinding process, and effectively solves the problems of core insert damage, poor end surface and poor height of the optical fiber of the core insert channel caused by the mini core MT core insert APC grinding process. And more than 16 inserting cores can be ground simultaneously, and the machining efficiency of the inserting cores is greatly improved. The utility model provides a mini type MT lock pin APC inclination structure, improvement lock pin return loss numerical value that can be very big, the performance is better.

Drawings

FIG. 1 is a schematic diagram of a polishing process according to an embodiment of the present disclosure;

FIG. 2 is a schematic diagram of an unground structure of a mini MT ferrule according to an embodiment of the present application;

FIG. 3 is a side view of the APC bevel structure of the mini MT ferrule according to the embodiment of the present application;

FIG. 4 is a schematic end view of a microscope with a mini MT ferrule in a rough grinding process in the embodiment of the present application;

FIG. 5 is a schematic end view of a microscope with a mini MT ferrule according to the embodiment of the present application;

FIG. 6 is a schematic end view of a microscope with a mini MT ferrule adopting a fiber drawing process in the embodiment of the present application;

fig. 7 is a schematic end view of a microscope of a mini MT ferrule in the polishing process in the embodiment of the present application.

Detailed Description

The present application will be further described with reference to the following detailed description.

The same or similar reference numerals in the drawings of the embodiments of the present application correspond to the same or similar components; in the description of the present application, it is to be understood that the terms "upper", "lower", "left", "right", "top", "bottom", "inner", "outer", and the like, if any, are used in the orientations and positional relationships indicated in the drawings only for the convenience of describing the present application and for simplicity of description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and therefore the terms describing the positional relationships in the drawings are for illustrative purposes only and are not to be construed as limiting the present patent.

Furthermore, if the terms "first," "second," and the like are used for descriptive purposes only, they are used for mainly distinguishing different devices, elements or components (the specific types and configurations may be the same or different), and they are not used for indicating or implying relative importance or quantity among the devices, elements or components, but are not to be construed as indicating or implying relative importance.

Example 1

As shown in fig. 1, an APC grinding process for a mini-type MT ferrule includes the following steps:

s1: fiber penetration and solidification: a plurality of optical fibers are penetrated into an optical fiber channel hole 1 of the mini type MT inserting core; and (3) injecting glue into the glue injection window 2 of the mini ferrule, and baking the mini MT ferrule at a high temperature to solidify the glue and fix the optical fiber.

S2: grinding pretreatment: cutting off the optical fiber beyond the end face of the mini MT insertion core after curing by using an optical fiber cutting tool, and then fixing the insertion core in a grinding disc, wherein the grinding disc is matched with a grinding device;

s3, coarse grinding: the grinding device selects grinding abrasive paper with abrasive grain size of 16um, and the grinding device grinds the end face of the insert core for 20-40 s under the requirements of coarse grinding speed and coarse grinding pressure; the coarse grinding process can remove residual glue on the end face of the ferrule after curing.

S4, polishing: the grinding device selects grinding abrasive paper with the grain size of 3 mu m, and the grinding device grinds the end face of the insert core at the grinding speed and the grinding pressure for 60-100 s; the polishing process is mainly used for the angle construction of the end face angle of the mini MT insertion core, so that the angle of the insertion core meets the specified inclination requirement and the horizontal step face requirement.

S5, fiber drawing: the grinding device selects grinding abrasive paper with abrasive particles with the particle size of 1um, grinding liquid is attached to the grinding paper, the grinding device grinds the end face of the insert core under the fiber drawing rotating speed and the fiber drawing pressure, and the grinding fiber drawing time is 95-120 s; the above steps mainly solve the problem of large height difference of optical fibers of each channel caused by the S3 or S4 process, so that the height of the optical fibers of each channel of the ferrule is controlled within a specified requirement range under the adjustment of the fiber drawing and grinding process, and the height difference of the optical fibers among the channels is reduced.

S6, polishing: the grinding device selects grinding abrasive paper with abrasive grain size of 0.5um, and grinds the end face of the insert core under the conditions of polishing rotation speed and polishing pressure, and the grinding and fiber drawing time is 70-110 s;

In example 1, the S1 penetration and solidification step includes: the optical fibers are arranged in a row and are horizontally inserted into the plug core; and (3) injecting glue into the optical fiber channel hole 1 of the ferrule of the inserted optical fiber through the glue injection window 2 of the ferrule, and then baking and curing at high temperature. The method specifically comprises the following steps: the optical fibers are brought into a horizontal row, the optical fibers are inserted into the empty ferrule optical fiber channel holes 1, and after the optical fibers are inserted, glue is injected through the glue injection window 2 of the ferrule, so that the optical fibers are fixed in the ferrule; and baking the insert core after injecting the glue, and curing the glue in the insert core.

In example 1, the step of polishing pretreatment of S2 includes: the insert core is inserted into a fixed clamp of the grinding disc, and the end face of the insert core is exposed out of the bottom of the grinding disc, and the fixed clamps of the grinding disc are all clamps with inclined angles, so that in the subsequent grinding process, the inclined angle of the end face of the insert core is consistent with the inclined angle of the clamp of the grinding disc. The grinding disc was then fixedly placed on a grinding apparatus, in this example 1, a center press type grinder was used.

In example 1, in the step of coarse grinding at S3, a grinding sandpaper having a grit size of 16 μm was selected, the end face of the ferrule was ground clockwise by the grinding apparatus at a coarse grinding speed of 70rmp to 90rmp, the coarse grinding pressure by the grinding apparatus was increased under a load of 3.0kg to 4kg, and the grinding time was 20S to 40S. In this embodiment 1, the abrasive paper may be silicon carbide abrasive paper; the rough grinding rotating speed is preferably 85 rmp; the rough grinding pressure may preferably be a load grinding pressure of 3.6kg, and the grinding time may preferably be 85 s. As shown in the enlarged view of the rough grinding end surface microscope in FIG. 4, the fiber passage hole 1 of the mini core MT ferrule is exposed, the optical fiber in the fiber passage hole is obviously concave, and the end surface glue of the fiber passage hole 1 is basically polished off. The process can remove the redundant curing glue on the end face in advance, so that the stress of the end face of the ferrule is balanced in the subsequent process, the stress area is uniform, the end face of the ferrule is flat, and the subsequent process is facilitated.

In example 1, in the step of polishing at S4, a polishing sand paper having an abrasive grain size of 3 μm was selected, the polishing device was used to polish the ferrule end face clockwise at a polishing rotational speed of 110rmp to 130rmp, the polishing pressure of the polishing device was set to 5.5kg to 8kg, and the polishing time was set to 70S to 95S. In this embodiment 1, the abrasive paper may be silicon carbide abrasive paper; the rough grinding rotating speed is preferably 120 rmp; the rough grinding pressure may preferably be a load grinding pressure of 6kg, and the grinding time may preferably be 80 s. As shown in the polished end-face microscope magnified view of fig. 5. Compared with the optical fiber end surface of the optical fiber channel subjected to the optical grinding process in the S3 rough grinding process, the optical fiber end surface of the optical fiber channel can not see redundant glue, meanwhile, the unevenness of the end surface is further reduced, in the optical grinding process, the angle of the end surface of the mini type MT core forms an inclined end surface 4 which is close to the inclined angle of a fixing clamp of a grinding disc, and meanwhile, a horizontal step surface 3 with a certain width can be reserved at one end of the ferrule and used for the interchangeability matching of APC structures between the ferrules.

In example 1, in the step of drawing fibers at S5, a polishing abrasive paper with abrasive grains of 1 μm was selected, and the polishing liquid was uniformly applied to the polishing paper, the polishing apparatus was used to polish the ferrule end face in the clockwise direction at a fiber drawing rotation speed of 130rmp to 155rmp, the fiber drawing pressure of the polishing apparatus was set to a load of 6kg to 8.5kg, and the polishing time was set to 100S to 130S. In this embodiment 1, the material of the abrasive paper is a polyester fiber coating layer coated with PEI film adhesive paper; the grinding fluid is cerium oxide grinding fluid; the fiber drawing speed is preferably 145 rmp; the fiber drawing pressure may preferably be a load grinding pressure of 7.5kg, and the grinding time may preferably be 110 s. As shown in the enlarged view of the fiber drawing end surface microscope in fig. 6, the smooth surface of the end surface of the ferrule is further improved compared to the polishing step of S4, and although the end surface of the ferrule has many scratches, the degree of the scratches is mostly light. Meanwhile, the fiber drawing process mainly aims to solve the problems of low height and large adjacent difference of multi-channel optical fibers caused by the S3 or S4 process, so that the height of the optical fibers of each channel is controlled within a specified requirement range in the grinding process, and the height difference of the optical fibers among the channels is reduced.

Table 1 fiber drawing process of the inventive lapping process compared to conventional undrawn process for finished product fabrication, fiber height comparison:

as can be seen from the table I, the height of the optical fiber of the fiber drawing process of the grinding process of the present invention is greater for each channel than the height of the optical fiber manufactured by the conventional undrawn finished product. Meanwhile, IEC61755-3-31 is used as a standard, and the height of the optical fiber needs to be 1000-3500 nm, so that the height of the optical fiber of a product manufactured by a finished product in the traditional non-fiber-drawing process cannot stably ensure that the height of the optical fiber of each channel in the MT ferrule meets the standard. The grinding process can effectively improve the condition that the optical fiber height of each ferrule channel in the MT ferrule is unstable.

In example 1, in the polishing step of S6, abrasive paper with abrasive grains of 0.5um was selected, the polishing device was used to polish the ferrule end face clockwise at a polishing rotational speed of 130rmp to 160rmp, the polishing pressure of the polishing device was increased under a load of 6kg to 8.5kg, and the polishing time was 70S to 90S. The number of polishing times is not less than 1, in this example 1, the material of the grinding paper is a polyester fiber coating layer coated by PEI film adhesive paper; the polishing speed is preferably 145 rmp; the polishing pressure may preferably be a load grinding pressure of 7.5kg, and the grinding time may preferably be 80 seconds. As shown in the magnified microscope image of the polished end face of fig. 7, there were no visually recognizable scratches and no visually recognizable defects on the end face at a microscope magnification of 400X, as compared to the previous process. The end face quality is extremely high.

In embodiment 1, in the cleaning and inspecting process of S7, the end face of the MT ferrule can be directly washed with a high-pressure water gun, and the water used for cleaning the MT ferrule needs to be distilled water. And after the flushing is finished, drying the water stain on the end face of the insert core by using a high-pressure air gun. And then using a 400X microscope to view the end face.

As shown in fig. 1, if there are few end-face defective products in the step S7, the grinding process can be performed once according to the requirements of the step S6, and the products do not need to be discarded and remade. The poor rejection rate of the product is greatly reduced.

The APC grinding process for the mini MT ferrule effectively solves the problems of damage of the mini ferrule, poor end face and poor height of the ferrule channel optical fiber during APC grinding of the ferrule. More than 16 inserting cores can be ground simultaneously, and the machining efficiency of the inserting cores is greatly improved

Meanwhile, the invention discloses an APC structure of a mini-type MT ferrule, which comprises the APC grinding process of the mini-type MT ferrule, and the structure is that one end of the end face of the ferrule is a horizontal step face 3, and the other end of the end face of the ferrule is an inclined end face 4; the angle alpha of the inclined end face is 5-10 degrees.

Compared with the multimode fiber return loss standard of a mini type MT insertion core with a PC structure: RL is more than or equal to 25dB, the actual test universal range is 25 dB-30 dB, the mini type MT ferrule of the APC structure directly improves the multimode fiber return loss standard of the mini type MT ferrule of the APC structure to RL more than or equal to 40dB, the actual test universal range is 45 dB-50 dB, and for single mode fiber, the return loss standard can even be directly improved to RL more than or equal to 60dB.

It should be understood that the above examples of the present application are only examples for clearly illustrating the present application, and are not intended to limit the embodiments of the present application. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present application shall be included in the protection scope of the claims of the present application.

Claims

1. An APC grinding process of a mini type MT ferrule is characterized by comprising the following steps:

s3: coarse grinding: the grinding device selects grinding abrasive paper with abrasive particle size of 16 microns, rotates at a coarse grinding rotating speed of 70-90 rmp, and is used for grinding under the load of 3.0-4 kg for 20-40 s;

s4: polishing: the grinding device is grinding abrasive paper with the grain size of 3 microns, and grinds the end face of the ferrule under the polishing rotation speed and the polishing pressure for 60-100 s;

s5: fiber drawing: the grinding device selects grinding abrasive paper with abrasive particle size of 1um, grinding liquid is attached to the grinding paper, the grinding device grinds the end face of the ferrule under the fiber drawing rotating speed and the fiber drawing pressure, and the grinding fiber drawing time is 95-120 s;

s6: polishing: the grinding device selects grinding abrasive paper with abrasive particles of 0.5um, rotates at a polishing rotating speed of 130-160 rmp, and is under the polishing pressure of 6-8.5 kg, and the grinding time is 70-90 s; the polishing frequency is not less than one time;

s7: cleaning and checking: cleaning the end face of the ferrule, and detecting the performance;

in the step S4, grinding sand paper with abrasive grains of 3um is selected, the grinding device rotates at a polishing rotation speed of 110 rmp-130 rmp, the polishing pressure of the grinding device is carried out under the load of 5.5 kg-8 kg, and the grinding time is 70S-95S;

in the step S5, abrasive sand paper with abrasive grains of 1um in particle size is selected, abrasive liquid is attached to the abrasive paper, the grinding device rotates at a fiber drawing rotating speed of 130 rmp-155 rmp, the fiber drawing pressure of the grinding device is carried out under the load of 6 kg-8.5 kg, and the grinding time is 100S-130S; the grinding paper is made of a polyester fiber coating layer coated with PEI (polyetherimide) film gummed paper; the grinding fluid is cerium oxide grinding fluid.

2. The APC grinding process for a mini MT ferrule according to claim 1, wherein in the step S3, the selected grinding paper is silicon carbide grinding paper.

3. The APC grinding process for a mini MT ferrule according to claim 2, wherein in the step S4, the selected grinding paper is silicon carbide grinding paper.

4. The APC grinding process for a mini MT ferrule according to claim 1, wherein in the step S6, the grinding paper is made of PEI film adhesive paper coated with a polyester fiber coating layer.

5. An APC structure of a mini MT ferrule, which is characterized by comprising the APC grinding process of the mini MT ferrule as claimed in any one of claims 1 to 4, wherein one end of the end face of the ferrule is a horizontal step face, and the other end of the ferrule is an inclined end face; the angle alpha of the inclined end face is 5-10 degrees.