Manufacturing process of a high-speed hybrid optical flexible cable

Abstract

The present invention belongs to the technical field of cable manufacturing, and in particular to a manufacturing process of a high-speed hybrid optical flexible cable, which includes the following process steps: etching a fiber optic channel pattern on the bare copper or aluminum areas of at least one top flexible printed circuit board and a bottom flexible printed circuit board; synchronously moving the top flexible printed circuit board and the bottom flexible printed circuit board and wrapping the synchronously moving optical fibers therein, and fixing the optical fibers in the fiber optic channel pattern through a prepreg; laminating and connecting the top flexible printed circuit board and the bottom flexible printed circuit board through a lamination process. By using the fiber optic channel pattern and the fixing tool, the present invention realizes the fixation of the optical fibers, and designs a special seam pattern, which can butt the two flexible printed circuit boards, and thus can manufacture high-speed hybrid optical flexible cables with a length of hundreds of meters, suitable for use in a variety of application scenarios.

Description

Technical Field

[0001] The present invention relates to the technical field of cable manufacturing, and particularly to a manufacturing process for a high-speed hybrid optical flexible cable. Background Art

[0002] In automotive ADAS systems, unmanned aerial vehicles (UAVs), drone systems, rocket systems, or missile systems, the distance between the sensor module and the processor can vary from a few meters to dozens or hundreds of meters, depending on the actual system application or limitations. Existing applications may require routing optical fibers in arbitrary shapes and lengths. The state-of-the-art minimum optical fiber bending radius differs from the manufacturing specifications of major brands in the current market by approximately 3 mm to 8 mm.

[0003] Due to the nature of the optical fiber's flexible inertia itself, it is usually difficult to place the optical fiber on a pre-designed trace without firmly fixing it. If the optical fibers are not firmly fixed during the manufacturing process, due to their elastic properties, they are likely to move away from these pre-designed traces.

[0004] In some application scenarios, the total length of the cable assembly can reach hundreds of meters, which is very different from traditional FPC application scenarios that only require 25 to 30 inches (or at most 1 meter).

[0005] Therefore, the present invention proposes a manufacturing process for a high-speed hybrid optical flexible cable. Summary of the Invention

[0006] Aiming at the problems existing in the prior art, the present invention provides a manufacturing process for a high-speed hybrid optical flexible cable.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A manufacturing process for a high-speed hybrid optical flexible cable, comprising the following process steps:

[0009] Etch an optical fiber channel pattern on the bare copper or aluminum area of at least one top flexible printed circuit board and a bottom flexible printed circuit board;

[0010] The top flexible printed circuit board and the bottom flexible printed circuit board move synchronously and wrap the synchronously moving optical fiber inside, and the optical fiber is fixed in the optical fiber channel pattern through a prepreg;

[0011] Press and connect the top flexible printed circuit board and the bottom flexible printed circuit board through a lamination process.

[0012] Further, when the number of the top flexible printed circuit boards and the bottom flexible printed circuit boards is not less than two, the docking of the two top flexible printed circuit boards or the bottom flexible printed circuit boards includes the following steps:

[0013] Mechanical dowel holes are opened on the alignment areas of the top flexible printed circuit board or the bottom flexible printed circuit board, and the two mechanical dowel holes are used for rough alignment through mechanical dowels;

[0014] Alignment marks are provided on the alignment areas of the top flexible printed circuit board or the bottom flexible printed circuit board for precise optical computer camera vision alignment;

[0015] When the two top flexible printed circuit boards or bottom flexible printed circuit boards are precisely aligned, the two top flexible printed circuit boards or bottom flexible printed circuit boards are connected together through conductive pads and mechanical fixtures.

[0016] Further, the alignment marks are in a sawtooth pattern.

[0017] Further, the number of the top flexible printed circuit boards is the same as that of the bottom flexible printed circuit boards.

[0018] Further, when the optical fiber is in the optical fiber channel pattern, the following processing steps are further included:

[0019] Apply prepreg on the optical fiber and / or the optical fiber channel pattern;

[0020] Scrape and dry the prepreg evenly in sequence through a squeegee.

[0021] Further, the prepreg uses epoxy resin or polyimide prepreg.

[0022] Further, the top flexible printed circuit board and the bottom flexible printed circuit board adopt polyimide or PTE flexible printed circuit materials, and the surfaces of the polyimide or PTE flexible printed circuit materials have copper foils or aluminum foils.

[0023] Further, before the optical fiber enters the optical fiber channel pattern, a pre-set optical fiber wiring guiding head is used to accurately enter the optical fiber channel pattern.

[0024] The above technical solutions of the present invention have the following beneficial technical effects:

[0025] The present invention realizes the fixation of the optical fiber through the use of the optical fiber channel pattern and the fixing tool, and designs a special seam pattern, which can butt-join two flexible printed circuit boards, and further can manufacture high-speed hybrid optical flexible cables with a length of hundreds of meters, suitable for use in a variety of application scenarios. Description of the Drawings

[0026] Figure 1 It is a wiring schematic diagram of the optical fiber in a high-speed hybrid optical flexible cable proposed by the present invention;

[0027] Figure 2 Schematic cross-section of a high-speed hybrid optical flexible cable proposed by the present invention;

[0028] Figure 3 Schematic manufacturing process of a high-speed hybrid optical flexible cable proposed by the present invention;

[0029] Figure 4 is Figure 3 Schematic diagram of the use of the fixing tool in

[0030] Figure 5 Schematic diagram of the alignment and connection of two top flexible printed circuit boards;

[0031] Figure 6 Schematic diagram of the sawtooth pattern.

[0032] Reference numerals in the figure: 1, top flexible printed circuit board; 2, bottom flexible printed circuit board; 3, optical fiber; 4, prepreg; 5, optical fiber channel pattern; 6, copper foil or aluminum foil; 7, optical fiber wiring guide head; 8, fixing tool; 801, dispensing needle; 802, scraper; 803, heating element; 9, mechanical guide pin hole; 10, alignment mark; 1001, sawtooth pattern; 11, conductive pad; Specific embodiments

[0033] To make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present invention.

[0034] As Figures 1-6 shown, the present invention provides a manufacturing process for a high-speed hybrid optical flexible cable, including the following process steps:

[0035] Etch the optical fiber channel pattern 5 on the bare copper or aluminum areas of at least one top flexible printed circuit board 1 and the bottom flexible printed circuit board 2. As Figure 1 shown, the wiring of the optical fiber 3 is usually in an irregular shape, and the shape of the flexible printed circuit board is also irregular. The channel spacing is etched by photolithography technology to match the diameter size of the optical fiber. For a bare optical fiber with only a cladding, this size is about 125 um, and for an optical fiber with an external coating material, this diameter is about 250 um;

[0036] The top flexible printed circuit board 1 and the bottom flexible printed circuit board 2 move synchronously and enclose the synchronously moving optical fiber 3 therein. The optical fiber 3 is fixed within the optical fiber channel pattern 5 through the prepreg 4 and the fixing tool 8. The fixing tool 8 includes a dispensing needle 801, a squeegee 802, and a heating element 803. The prepreg 4 is injected through the dispensing needle 801, then spread evenly by the squeegee 802, and finally cured by the heating element 803. The prepreg 4 can firmly bond the top flexible printed circuit board 1 and the bottom flexible printed circuit board 2, while filling any gaps between the top flexible printed circuit board 1 and the bottom flexible printed circuit board 2.

[0037] The top flexible printed circuit board 1 and the bottom flexible printed circuit board 2 are press-connected through a lamination process.

[0038] In a specific embodiment of the present invention, to ensure the precise alignment between the panels, a special seam pattern is designed. When the number of the top flexible printed circuit boards 1 and the bottom flexible printed circuit boards 2 is not less than two, the docking of two of the top flexible printed circuit boards 1 or the bottom flexible printed circuit boards 2 includes the following steps:

[0039] Mechanical dowel holes 9 are opened on the alignment areas of the top flexible printed circuit board 1 or the bottom flexible printed circuit board 2. The two mechanical dowel holes 9 are used for rough alignment through mechanical dowels.

[0040] Alignment marks 10 are provided on the alignment areas of the top flexible printed circuit board 1 or the bottom flexible printed circuit board 2 for precise optical computer camera vision alignment.

[0041] When the two top flexible printed circuit boards 1 or the bottom flexible printed circuit boards 2 are precisely aligned, the two top flexible printed circuit boards 1 or the bottom flexible printed circuit boards 2 are connected together through conductive pads 11 and mechanical jigs, thereby realizing the precise manufacturing of a high-speed hybrid optical flexible cable with a length of several hundred meters.

[0042] In a specific embodiment of the present invention, the alignment mark 10 is a sawtooth pattern 1001.

[0043] In a specific embodiment of the present invention, the number of the top flexible printed circuit boards 1 and the bottom flexible printed circuit boards 2 is the same.

[0044] In a specific embodiment of the present invention, when the optical fiber 3 is within the optical fiber 3 channel pattern, the following processing steps are further included:

[0045] The prepreg 4 is applied to the optical fiber 3 and / or the optical fiber channel pattern 5.

[0046] The prepreg 4 is spread evenly and dried in sequence by the squeegee 802.

[0047] In a specific embodiment of the present invention, the prepreg 4 is an epoxy resin or polyimide prepreg. The fiber guiding tip pulls the optical fiber out of the fiber reel and guides each optical fiber into the target channels etched on the flexible printed circuit board. Then, epoxy resin adhesive is dispensed onto the fiber guiding channels. After the squeegee, epoxy resin is dispensed to smooth the epoxy resin and flatten the epoxy resin adhesive before lamination. There is a heating element behind the squeegee that can immediately cure the epoxy resin to ensure that the optical fiber is correctly fixed. The temperature and heating time of the heating element are appropriately controlled to ensure that the epoxy resin has just hardened. Then, the entire cable assembly undergoes a lamination process before being cut into its final shape.

[0048] In a specific embodiment of the present invention, the top flexible printed circuit board 1 and the bottom flexible printed circuit board 2 are made of polyimide or PTE flexible printed circuit materials, and the surfaces of the polyimide or PTE flexible printed circuit materials have copper foil or aluminum foil 6.

[0049] In a specific embodiment of the present invention, before the optical fiber 3 enters the optical fiber channel pattern 5, a pre-set optical fiber wiring guiding head 7 is used to accurately enter the optical fiber channel pattern 5.

[0050] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A manufacturing process for a high-speed hybrid optical flexible cable, characterized in that: The process steps include: etching a fiber channel pattern on a bare copper or aluminum area of ​​at least one of the top flexible printed circuit board and the bottom flexible printed circuit board; The top flexible printed circuit board and the bottom flexible printed circuit board move synchronously and wrap the synchronously moving optical fiber therein, and the optical fiber is fixed in the optical fiber channel pattern by prepreg; Press-connecting the top flexible printed circuit board and the bottom flexible printed circuit board by a lamination process; When the number of the top flexible printed circuit boards and the bottom flexible printed circuit boards is not less than two, the two top flexible printed circuit boards or the bottom flexible printed circuit boards are butted together, comprising the following steps: Opening mechanical guide pin holes on the alignment area of ​​the top flexible printed circuit board or the bottom flexible printed circuit board, wherein the two mechanical guide pin holes are used for rough alignment by mechanical guide pins; providing alignment marks on the alignment area of ​​the top flexible printed circuit board or the bottom flexible printed circuit board for precise optical computer camera vision alignment; When the two top flexible printed circuit boards or the two bottom flexible printed circuit boards are precisely aligned, the two top flexible printed circuit boards or the two bottom flexible printed circuit boards are connected together by means of a conductive pad and a mechanical clamp; Before the optical fiber enters the optical fiber channel pattern, a pre-set optical fiber wiring guide head is used to accurately enter the optical fiber channel pattern.

2. The manufacturing process of a high-speed hybrid optical flexible cable according to claim 1, characterized in that: The alignment mark is a sawtooth pattern.

3. The manufacturing process of a high-speed hybrid optical flexible cable according to claim 1, characterized in that: The number of the top flexible printed circuit boards is the same as the number of the bottom flexible printed circuit boards.

4. The manufacturing process of a high-speed hybrid optical flexible cable according to claim 1, characterized in that: When the optical fiber is within the optical fiber channel pattern, the process further includes the following steps: applying prepreg on the optical fiber and / or the optical fiber channel pattern; The prepreg is then smoothed and dried using a scraper.

5. The manufacturing process of a high-speed hybrid optical flexible cable according to claim 4, characterized in that: The prepreg is epoxy resin or polyimide prepreg.

6. The manufacturing process of a high-speed hybrid optical flexible cable according to claim 1, characterized in that: The top flexible printed circuit board and the bottom flexible printed circuit board are made of polyimide or PTE flexible printed circuit material, and the surface of the polyimide or PTE flexible printed circuit material has copper foil or aluminum foil.

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