专注福禄克测试仪销售与技术

The CertiFiber Pro accepts APC connectors in the?INPUT port ONLY. The APC connector can be attached to the INPUT port because the INPUT port is a non-contact mating. This design feature allows you to set a 1 jumper reference for SC, ST, FC, SC/APC and LC/APC fiber testing.

该福禄克FLUKE?CertiFiber PRO(CFP-100-Q,CFP-100-M,CFP-100-S)光纤测试仪的APC端口，只使用于输入端口。APC端口能够适用于输入端口，因为输入端口是非接触式连接。此设计功能允许您设置光纤测试参考为1个跳接对于SC，ST，FC，SC /APC和LC /?APC

The?OUTPUT port uses a UPC connector. This makes a physical contact with the test reference cord. As a result, you cannot insert SC/APC connectors in the OUTPUT port of the tester. No damage will occur; you will simply get a warning from the tester about the received power being too low.

APC – Angled Physical Contact
These connectors are color coded green and are found in single mode fiber applications. The end face is slanted 8 degrees. The slight angle reduces back reflections in the core because the reflections are absorbed into the cladding. With CertiFiber Pro, you will need two hybrid UPC to APC cords and two APC to APC cords. Details on the methodology can be found in the two links below:

• Certifying LC/APC links with the CertiFiber Pro
• Certifying SC/APC links with the CertiFiber Pro

UPC – Ultra Physical Contact
These connectors are color coded blue for single mode and beige for multimode. The end face of the fiber has an apex so the core makes direct contact to the other core in a mated connection. A PC (Physical Contact) connector has a flat end face increasing the likelihood that an air gap will be present because the cladding can touch before the core does due to its less rounded end face geometry. That air gap with result in an increase in reflectance – something fiber systems do not want to see.

拓展阅读：

PC指的是紧密接触（physical contact)，同样是紧密接触，根据回波损耗的不同，连接器分为PC, SPC，UPC和APC。SPC指的是super physical contact, UPC指的是ultra physical contact。PC, SPC和UPC工业标准规定的回波损耗分别为-35dB, -40dB和-50dB (回波损耗是指有多少比例的光又被连接器的端面反射，回波损耗越小越好，当然你也可以说回波损耗的值越大越好，不考虑前面那个负号）。不同的连接器原则上不能混接，但PC, SPC和UPC的光纤端面都是平面的，差别在磨的质量，所以，PC,SPC和UPC的混连还不至于对连接器形成永久性的物理损伤。
APC则完全不同，它的端面被磨成一个8度角，就是减少反射，其工业标准的回波损耗为-60dB。APC连接器只能与APC相连接。由于APC的结构与PC完全不同，如果用法兰盘将这两种连接器连接，就会损坏连接器的光纤端面。连接APC到PC的办法：通过PC到APC转换的光纤跳线来实现。另外要说明的是APC连接器通常是绿色的（而黄色的光纤则只是单模光纤），而且人眼就能看到光纤端面的倾斜。
因此，为了避免实验过程中连接器使用的混乱（避免毁坏光谱仪等输入端口），今后我们在购买激光器，跳线等时，应统一要求厂家给配APC连接器。
FC/PC FC/UPC FC/APC能够混合连接，信号衰减不会很大，按照国标插损应该是小于0.5dB。应用主要取决于适配器的类型，一般通信ODF架用FC多，设备光口用SC多，ST在局域网和广电较多。