Fiber Optic splitter, also known as optic splitter, is one of the important passive devices in the optic fiber link. It is an optic fiber tandem device with multiple input ends and multiple output ends. The optic splitter can be divided into two types: fusion type (FBT splitter) and planar waveguide type (PLC splitter) according to the optic splitting principle.
[caption id="attachment_2391" align="alignnone" width="600"] fiber optic splitter factory[/caption]
The optic splitter can be divided into two types: fusion type (FBT Splitter) and planar waveguide type (PLC Splitter) according to the principle of spectroscopy. The fusion method is to remove two (or more than two) optic fibers from which the coating layer is removed.
According to the fixed method, it melts under high temperature heating and stretches to both sides at the same time. Finally, a special waveguide structure in the form of a double cone is formed in the heating zone. By controlling the twisting angle of the optic fiber and the length of stretching, different splits can be obtained proportion. Finally, the taper area is cured on the quartz substrate with curing glue and inserted into the stainless copper tube. This is the optic splitter. In this production process, the thermal expansion coefficient of the cured adhesive is inconsistent with that of the quartz substrate and stainless steel tube, and the degree of thermal expansion and contraction is inconsistent when the ambient temperature changes. This situation is likely to cause damage to the optic splitter, especially the optic splitter. The situation in the wild is even worse, which is also the main reason why the optic branch is easily damaged. For the production of more splitters, multiple splitters can be used.
[caption id="attachment_2393" align="alignnone" width="600"] fiber optic splitter principle[/caption]
3. Technical Parameters
3.1 Insertion loss
The insertion loss of the optic splitter refers to the number of dB of each output relative to the input optic loss. The mathematical expression is: Ai = -10lg Pouti / Pin, where Ai refers to the insertion loss of the i-th output port; Pouti is The optic power of the i-th output port; Pin is the optic power value of the input end.
The additional loss is defined as the DB number of the total optic power of all output ports relative to the input optic power loss. It is worth mentioning that for fiber couplers, the additional loss is an indicator that reflects the quality of the device manufacturing process, and reflects the inherent loss of the device manufacturing process. The smaller the loss, the better, and it is the evaluation index of the quality of the production. The insertion loss only shows the output power status of each output port, not only has the inherent loss factor, but also considers the effect of the split ratio. Therefore, the difference in insertion loss between different fiber couplers does not reflect the quality of device fabrication. The additional loss for the 1 * N single-mode standard optic splitter is shown in the following table:
Number of branches 2 3 4 5 6 7 8 9 10 11 12 16
Additional loss DB 0.2 0.3 0.4 0.45 0.5 0.55 0.6 0.7 0.8 0.9 1.0 1.2
3.2 Split ratio
The splitting ratio is defined as the output power ratio of each output port of the optic splitter. In system applications, the splitting ratio is indeed based on the amount of optic power required by the actual system optic node to determine the appropriate splitting ratio (except for average distribution), The splitting ratio of the optic splitter is related to the wavelength of the transmitted light. For example, when an optic splitting transmits 1.31 micron light, the splitting ratio of the two output ends is 50:50; when transmitting 1.5μm light, it becomes 70: 30 (The reason why this happens is because the optic splitter has a certain bandwidth, that is, the bandwidth of the optic signal transmitted when the split ratio is basically unchanged). So be sure to indicate the wavelength when ordering the optic splitter.
Isolation refers to the isolation capability of one optic path of an optic splitter to optic signals in other optic paths. Among the above indicators, the isolation is more important for the optic splitter. In actual system applications, devices with isolation above 40dB are often required, otherwise it will affect the performance of the entire system.
In addition, the stability of the optic splitter is also an important indicator. The so-called stability means that when the external temperature changes and the working status of other devices changes, the splitting ratio of the optic splitter and other performance indicators should remain basically unchanged. In fact, the stability of the optic splitter depends entirely on the manufacturer's process level. The quality of products from different manufacturers is quite different. In practical applications, I have indeed encountered many inferior optic splitters, which not only deteriorate the performance index quickly, but also have a very high damage rate. As an important component of the optic fiber trunk, you must pay attention when purchasing, not just look at it The price, the price of the optic branch with low technological level must be low.
In addition, uniformity, return loss, directivity, and PDL all occupy very important positions in the performance index of the optic splitter.
4. Packaging method
The optic splitter equipment package should be cost-effective, sturdy, and compact. The internal optic fiber of the equipment should ensure a certain coil radius and the coiled optic fiber should not be damaged. All devices should be well fixed and provide sufficient for management, connection, and installation , Maintenance, inspection and testing space.
This standard mainly defines the following five types of optic splitter with encapsulation structure to adapt to different installation facilities and installation environments. The shape and size of different encapsulated optic splitters should meet the requirements of Appendix A.
Optic splitter packaging
Name encapsulation method Port type Applicable scope
Box-type optic splitter, box-type package, with pigtail type, desktop, tray, optic cable transfer box, etc.
Rack type optic splitter Rack type package Adapter type 19 inch standard rack
Miniature optic splitter Miniature package Pigtail type without plug
Pigtail type with plug
Optic cable connector box, splitter box, etc.
Tray-type optic splitter Tray-type package Adapter type Optic fiber distribution frame or optic cable transfer box, etc.
Plug-in optic splitter Plug-in package Adapter type Optic fiber distribution frame, optic cable junction box, optic splitter
Box, etc., used with plug-in box
The optic splitter of other packaging forms does not make clear requirements, and can be customized according to the actual needs of various places. All performance indicators refer to
This standard is implemented.
The adapter of the optic splitter should choose SC, FC, LC and other types according to the needs. In order to reduce the volume of the equipment and save the installation space
Between time, the optic splitter can use LC adapter. Technical conditions should be in accordance with YD / T 1272.3-2005 (SC type), YD / T
1272.4-2007 (FC-UPC type, FC-APC type), YD / T 1272.1-2003 (LC type) and other relevant regulations.
The end face is mainly UPC, and the APC end face adapter is mainly used when carrying analog CATV signals.
6.3 Requirements for pigtails
The pigtails of the box optic splitter should use Φ2mm optic cable, and the pigtails of the micro optic splitter should use Φ0.9mm
Optic cable or Φ0.25mm optic fiber. The fiber in the pigtail should comply with the ITU-T G.657A standard.
For the Φ0.25mm fiber optic splitter without plug, the output end should use a group of 8-core fiber ribbon, fiber ribbon technology strip
The parts shall comply with the relevant provisions of the YD / T 979-2009 standard, and the optic fiber ribbon chromatography shall be arranged in accordance with the requirements of YD / T 979-2009, specific
See Table 2. Optic splitters with a splitting ratio greater than 8 need to use multiple sets of fiber ribbons, and labels should be attached to the end of each group of fiber ribbons to distinguish
Each group of optic fiber ribbons.
Table 2 Fiber ribbon chromatography requirements
No. 1 2 3 4 5 6 7 8
Chromatography Blue Orange Green Brown Grey White Red Black
The length of the pigtails can be customized according to actual needs.