PC/APC/UPC refers to different polishing methods of optical fiber connectors on optical fiber jumpers, and different polishing methods determine the quality of optical fiber transmission, mainly reflected in return loss and insertion loss. So what is the difference between these three grinding methods?
1.What is a PC?
PC (Physical Contact, and physical contact) is the most common polishing method for optical fiber connectors on optical fiber jumpers, and is widely used in telecom operators' equipment. Although the end face of the optical fiber connector looks flat, in fact, the end face is slightly bent and polished, and the highest point of the bend is the center of the core, which can effectively reduce the air gap between the optical fiber components. Generally, the optical fiber of the PC grinding method is used. The return loss of the jumper is -40dB.
2. What is UPC?
UPC (Ultra Physical Contact) is an evolution of PC. It optimizes the polishing of the end face to obtain a better surface finish. UPC is the same as PC, its highest point of bending is in the center of the fiber core, but UPC return loss is higher than PC, generally -50dB (or even higher). It is usually used in Ethernet network equipment (such as ODF optical distribution frames, media converters and optical switches, etc.), but also in telephone systems.
3. What is APC?
APC (Angled Physical Contact) is the latest technology of optical fiber end face polishing. Its end face adopts an 8-degree angle polishing method to make the end face polishing more accurate, which can effectively reduce reflection, and the return loss is about -60dB. APC is generally used for optical radio frequency applications in high wavelength ranges such as CATV.
