1、Transmission mode
It refers to the mode of transmission of light in the fiber (electromagnetic field distribution form). Commonly used communication fiber mode is divided into single-mode and multimode, single-mode suitable for long-distance transmission, multimode suitable for close transmission. g652D single-mode fiber core diameter d1 for 9um cladding diameter d2 for 125um, multimode fiber commonly used is divided into 62.5/125 or 50/125 two forms.
Fiber mode selection must match the optical module, otherwise the core diameter mismatch causes additional loss, different core diameter fiber optic cable is not recommended for interconnection between
2、Insertion loss
When using fiber optic connectors for connection, the amount of optical signal power reduction value, usually expressed in decibels. For example: when the insertion loss of 3dB, optical power loss of about 50%, when the insertion loss of 1dB, power loss of about 20%, IL = -10lg (output optical power / input optical power).
3, return loss
Also known as reflection loss, refers to the parameters of signal reflection performance, return loss describes the amount of optical signal returned to the original return value, generally the greater the better. For example: input 1mw power, of which 10% is reflected back, is 10dB, 0.003% is reflected back, the return loss is about 45dB. RL = -10lg (reflected optical power / input optical power)
4, face type
Fiber face type is divided into PC (spherical grinding) and APC (oblique spherical grinding). APC grinding, the reflected beam returned along the original path is greatly reduced, helping to improve the return loss of the connector.
