Optical fiber connector Transmission principle
Optical end connectors are the core components of a Optical Fiber Connector. Unlike the circumferential contact conduction of electrical contact parts, optical end connectors generally pass through the end-face contact type transmission, through the end surface polishing to achieve the best optical performance and good mechanical properties, optical signal along the fiber from the end of the connector into the other end.
1, optical end connectors by the high precision of the ceramic pin and the correction of the casing, fiber fixed in the ceramic insert needle inside the hole, end face polishing, through the ends of the spring to tighten, so that its reliable contact. The diameters of the ceramic pins used in the contact parts are generally φ2.5mm, φ1.25mm and so on, the diameter and coaxial degree of the accuracy of up to 0.1um.
2, MT-type optical end-connector is a kind of end connectors for multi-core Optical Fiber Connectors. The main material is PPS, which is an important component of MPO, MTP and other optical fiber connectors. The connector with MT Optical end connectors generally has higher density, and single end connectors can achieve up to 72 optical signal transmission at the same time. The end-connector adopts the guide pin-guide correction at both ends, so that the multiple fibers are simultaneously aligned in the pins.
Optical Connectors-Performance indicators
1. Transmission mode
Refers to the transmission of light in the optical fiber (electromagnetic field distribution form). Commonly used communication optical fiber mode is divided into Single-mode and multimode, single-mode suitable for long-distance transmission, multimode suitable for close-range transmission. g652d Single-mode Fiber Core diameter D1 is 9um cladding diameter D2 is 125um, multimode fiber commonly used is divided into 62.5/125 or 50/125 two forms.
The selection of optical fiber mode must match with the optical module, otherwise the core diameter mismatch will cause additional loss, and the interconnection between different core diameter fiber optic cable is not recommended.
2. Insertion loss
When connecting using a Optical Fiber Connector, the amount of light signal power reduction is usually expressed in decibels. For example: When the insertion loss is 3dB, the optical power loss is about 50%, and when the insertion loss is 1dB, the power loss is about $number, IL=-10LG (Output light power/input light power).
3. Echo Loss
Also known as reflection loss, refers to the signal reflection performance parameters, the return loss is described by the optical signal returned to the original path of the amount of return, generally the larger 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 light power/input light power)
The fiber face is divided into PC (spherical grinding) and APC (oblique spherical grinding). After the APC is grinded, the reflected beam returned along the original path is greatly reduced, which helps to improve the echo loss of the connector.