PLC Splitter process, planar optical waveguide splitter process

With the development of optical fiber communication industry's recovery as well as FTTX, optical splitter (Splitter) spring is coming in the market. Currently there are two main optical splitter types: one is the traditional production technology of optical passive devices (tapered coupled method) production of fused biconical taper Optical Fiber Coupler; another is the use of integrated planar optical waveguide produced optical technology (PLC) taps.

PLC splitters are today's research hot spots at home and abroad, which have very good prospects, however PLC Splitter package is the difficulty of manufacturing PLC Splitter. PLC splitters internal structure PLC Splitter package refers to optical Planar waveguide splitters on the various pathway (pathway) and fiber in the optical fiber array one by one on the, and then the specific glue (epoxy) will be bonded together technology.

PLC splitters with optical fiber array alignment precision is the key to this technology.

PLC Splitter package involves six-dimensional fiber array with optical waveguide closely aligned, difficult. When using the manual operation, its disadvantage is inefficiency, poor repeatability, human factors and it is difficult to achieve large-scale production, and so on. PLC splitters real photos.

PLC Splitter production ---PLC Splitter using semiconductor technology (lithography, etching, developer technology) production. Optical waveguide array is located on the chip surface, tap functionality on the chip, which is implemented on a chip, 1 bisecting roads; then, chip ends respectively coupled input and output of multiple channel fiber-optic array and packages.

Its internal structure and physical photo is as shown in Figure 1, 2 respectively. And fused biconical taper taps compared, advantages of PLC splitters are:

(1) loss on optical wavelength-insensitive, to meet the transport needs of different wavelengths.

(2) uniform light, signal can be evenly distributed to the user.

(3) compact structure, small size, can be installed directly within the existing junction box, does not leave much room to install required.

(4) single device to tap many channels, can be more than 32 channels.

(5) multiple low cost, large ones more, more obvious cost advantages.

At the same time, PLC main shortcomings of the tap are:

(1) complex production processes, technical threshold higher, chip currently monopolized by foreign companies, domestic production of bulk packaging enterprises are rare.

(2) with respect to the high cost of fused biconical taper tap, particularly in low channel taps more at a disadvantage.

PLC Splitter package technology PLC splitters encapsulates process including coupling alignment and bonding, and so on. PLC Splitter chip with optical fiber array manual and automatic coupling alignment of two kinds, they were dependent on hardware there are six-dimensional precision trimming, lighting, power meter, microscope observation system, automatic alignment is the most common, it is formed by optical power feedback closed-loop control, thus coupling of butt and docking accuracy and high efficiency PLC tap Manager package main process is as follows:

(1) coupled alignment of prepared work: first will wave guide cleaning clean Hou carefully to installed to wave guide frame Shang; again will fibre cleaning clean, end installed in incident end of precision adjustment frame Shang, another end received Shang light (first received 6.328 Micron of red light, to preliminary debugging pass light Shi observation posts with)

(2). Through observation of the microscopic observation system incident position of the fiber and waveguide and computer instructions to manually adjust the parallelism of optical fiber and waveguide and end interval.

(3) open the laser source, observed under microscopy system image of the x and y axes, and with waveguide output light spot initial judgement incident fiber and waveguide coupling alignment, in order to achieve optical fiber and waveguide butt good light effects.

(4) when the observation of microscopic observation system to waveguide spot after achieving the desired effect on the output side, remove the microscopic observation system.

(5) waveguide output fiber array (FA) first and eighth channel clean and blow balloons blown dry. Step (2) method of waveguide output and fibre arrays connected and preliminary adjustment to a suitable location. And then connect it to two detection of dual-channel power meter interfaces.

(6) will fibre array included shot end 6.328 micron wavelength of light switch for 1.31/1.55 Micron of light, started light power search program automatically adjustment wave guide output end and fibre array column of location, makes wave export shot end receives to of light power value maximum, and two a sampling channel of light power value should as far as possible equal (that automatically adjustment output end fibre array column, makes its and wave import shot end achieved precise of alignment, thus improve overall of coupled efficiency) Figure 3. 1 branch PLC Splitter chip package structure.

(7) when the waveguide optical power output fiber array values. After it reaches the maximum and equal as possible, and then dispensing work.

(8) repeat step (6), once again looking for waveguide output fiber array receives the maximum value of the optical power, to ensure the dispensing of waveguide and optical fiber array after the best coupling alignment, and curing it, and then follow up, complete package.

In above of coupled alignment process in the, PLC tap Manager has 8 a channel and each channel are to precise alignment, due to wave guide chip and fibre array column (FA) of manufacturing technology guarantee has all channel between of relative location, so just to PLC tap Manager and FA of first channel and eighth channel while alignment, will can guarantee other channel also achieved has alignment, such can reduced package of complex degree.

In the encapsulation operation is most important and highest technical difficulty in coupling alignment operations, which include reconciling perfect alignment at the beginning two steps. Adjustable to allow waveguide to good light; precise purpose is to complete the best optical power coupling alignment points precise positioning, it is search program to implement of optical power Max.

Requires 6-DOF docking optical waveguides, 3 translational (x, y, z) and 3 rotation (alpha, beta, and g), to make the good package waveguide devices, the alignment of translation accuracy should be controlled within 0.5 micrometres, accuracy should be better than 0.05 degrees of rotation. 1x8 PLC Splitter package 1 branches PLC splitters are encapsulated and packaging of the encapsulated coupling alignment process uses introduced above process. After alignment package structure as shown in Figure 3, encapsulated component is composed of PLC Splitter chip and fibre arrays.Connecting part of the PLC Splitter chip, in order to ensure mechanical strength and long-term reliability of connections, piece glue stick on the glass. Mechanical method for fiber array is on the glass in a 250 Micron-pitch processing into v-shape Groove, fiber array is then fixed this. The highest cumulative production of 8-core fiber array interval error average of 0.48 μm, accuracy is very high.

PLC Splitter chip with optical fiber array connection, as well as all parts in the Assembly process, in order to reduce Assembly time, the use of UV-curing adhesive. Fibre optic connection interface is key in maintaining long-term reliable, fluoride should use wet resistance split chain material combination of epoxy and silane cementation medicinal preparation.

In order to reduce the reflection of face, 8 ° grinding technology.

Connected and assembled fiber array PLC Splitter chip is packaged in a metal (aluminum) in shell-and-tube. 1 branch of components overall dimensions of approximately 40X4X4.

This article comes from http://www.flachfiber.com , if reprinting please indicate the source.