PLC Splitter: Planar Waveguide Circuit splitter
PLC Splitter uses semiconductor technology (lithography, etching, development and other technologies) to make optical waveguide branch devices, based on planar light wave circuit technology.
The composition structure of PLC Splitter: pigtail, core chip, fiber array, shell (ABS box, steel pipe), connector and fiber optic cable, etc.
The production process of PLC Splitter
Based on the planar optical waveguide technology, the optical input is evenly converted into multiple optical outputs with a precise optical coupling process.
PLC Splitter Features: Due to the optical waveguide technology, the process stability and consistency are good, the loss is not related to the optical wavelength, the channel uniformity is good, the structure is compact and the volume is small.
The optical waveguide array is located on the upper surface of the chip, and the shunt function is integrated on the chip.
Both PLC Splitter and FBT Splitter are based on the cascade of 1 x 2 basic structure. The 1 x 2 structure of the FBT is a coupler, and the PLC is a Y-branch structure. This seemingly simple Y branch component is actually not simple, because the performance of the splitter is largely determined by it.
Tips: It is also based on the Y-branch structure, which can roughly explain why the 1 x 2 splitter has an insertion loss of 3 dB whether it is an uplink or a downlink signal.
Packaging of PLC splitter
It refers to the technology of aligning each light guide path (ie, waveguide path) on the planar waveguide splitter with the fibers in the fiber array, and then bonding them together with a specific glue (such as epoxy glue).
The packaging of the PLC splitter involves the six-dimensional tight alignment of the fiber array with the optical waveguide, and the alignment accuracy is the key to the technology.
The packaging of PLC splitter is a difficult point in the manufacture of PLC splitter.
PLC splitter packaging process:
1. Preparation for coupling alignment
Clean the waveguide first and then carefully install it on the waveguide frame. Then clean the optical fiber, install one end on the precision adjustment frame at the incident end, and connect the other end to the light source.
2. Observe the position of the optical fiber and the waveguide at the incident end with the help of a microscopic observation system, and manually adjust the parallelism and end face spacing between the optical fiber and the waveguide through computer instructions.
3. Turn on the laser light source, according to the X-axis and Y-axis images observed by the microscope system, and use the light spot at the output end of the waveguide to preliminarily judge the coupling and alignment of the optical fiber at the incident end and the waveguide, so as to achieve a good light-passing effect when the optical fiber and the waveguide are docked.
4. When the microscopic observation system observes that the light spot at the output end of the waveguide achieves the desired effect, remove the microscopic observation system.
5. Clean the first and eighth channels of the fiber array (FA) at the output of the waveguide and dry them with a blower. Next, the method of step 2 is used to connect the output end of the waveguide to the optical fiber array and initially adjust it to an appropriate position. Then connect it to the two probe ports of the dual channel power meter.
6. Switch the light source with a wavelength of 6.328 μm at the incident end of the fiber array to a light source with a wavelength of 1.310/1.550 μm, and start the optical power search program to automatically adjust the position of the waveguide output end and the fiber array. Maximize the optical power value received by the transmitting end of the waveguide, and the optical power values of the two sampling channels should be as equal as possible (that is, automatically adjust the optical fiber array at the output end to achieve precise alignment with the transmitting end of the waveguide, thereby improving the overall coupling efficiency).
7. When the optical power value of the optical fiber array at the output end of the waveguide reaches the maximum and is as equal as possible, the dispensing work is carried out.
8. Repeat steps
9. Find the maximum value of the optical power received by the optical fiber array at the output end of the waveguide again to ensure the optimal coupling alignment between the waveguide and the optical fiber array after dispensing, and then solidify it, and then perform subsequent operations to complete the packaging.
PLC Splitter Application：
- FTTH, LAN, PON & Optical CATV
- Local ring net, Optical fiber communication system
- Optical fiber test equipment, Optical fiber sensor
Split Ratio of PLC Splitter
The split ratio is determined by the input and output of the fiber optic cable splitter. The split ratio of the PLC splitter is up to 1:64. One or two inputs, with a maximum output of 64 fibers. The waveguide plays a key role in the splitting process that allows a certain percentage of light to pass through, so the signal can be equally divided. PLC Splitter is not customizable. Only 1:4, 1:8, 1:16, 1:32, 1:64 and other standard versions.
PLC splitters can support wavelengths from 1260 to 1650nm. The wavelength tunable range makes PLC splitters suitable for more applications.
Common Types of PLC Splitters
PLC splitters are available with a variety of single-mode and multi-mode fibers, the most common fiber connector types for various applications. Generally, there are bare fiber PLC splitters, mini module PLC splitters, box type PLC splitters and rack mount PLC splitters.
Bare fiber PLC splitters
Bare fiber PLC splitters are used in tight spaces and can be easily placed in junction boxes and fiber optic splice closures.
Mini module PLC splitters
Mini module PLC splitters are mainly used for 0.9mm fiber, where ribbon fiber can be converted to 0.9mm fiber by fan-out. Fiber optic connectors are available for the input and output of these splitters.
Bare fiber type PLC optical splitter and mini module tube type PLC optical splitter are the smallest optical splitters among all PLC optical splitters. The end of each optical fiber of the mini module tube type PLC optical splitter is terminated with an optical fiber connector, which is often installed in the optical cable splice box, the module box and the distribution box.
Box type PLC splitters
Box type PLC splitters use PLC packaging technology in order to divide a wavelength into multiple ports.
Rack mount PLC splitters
Rack mount PLC splitter is a key component of FTTH and is responsible for distributing the signal from the fiber to the number of houses.
Advantages of PLC splitters
- Suitable for a variety of working wavelengths (1260nm – 1650nm).
- The allocator ratio is equal for all branches.
- The configuration is compact, the volume is smaller, and the space is small.
- All ratios have good stability. High quality, low failure rate.
Disadvantages of PLC splitters
- More expensive than FBT separators in smaller ratios.
- The production process is complicated.