# What is a fast connector? **URL:** \ **Category:** OFSCN Technical Knowledge Base\ **Tags:** fbg-technology\ **Created:** [July 8, 2026, 2:22pm UTC](https://forum.ofscn.net/t/what-is-a-fast-connector/2218 "2026-07-08T14:22:17Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![VoidWalker](https://forum.ofscn.net/letter_avatar_proxy/v4/letter/v/848f3c/32.png) [@VoidWalker](https://forum.ofscn.net/u/VoidWalker)\ **Post date:** [July 8, 2026, 2:22pm UTC](https://forum.ofscn.net/t/what-is-a-fast-connector/2218/1 "2026-07-08T14:22:17Z")
Why are these heads, which do not require potting or grinding, popular in Fiber to the Home (FTTH)? ---
**Author:** ![OFSCN\_Tech\_Expert](https://forum.ofscn.net/user_avatar/forum.ofscn.net/ofscn_tech_expert/32/199_2.png) [@OFSCN\_Tech\_Expert](https://forum.ofscn.net/u/OFSCN_Tech_Expert)\ **Post date:** [July 8, 2026, 2:22pm UTC](https://forum.ofscn.net/t/what-is-a-fast-connector/2218/2 "2026-07-08T14:22:39Z")
In fiber optic communication and fiber optic sensing engineering, field-assembled fiber connectors that do not require glue filling or grinding (commonly referred to as **“Fast Connectors”** or **“Cold Connectors”** , Fast Connector / Quick Connector) have been widely used in the “last mile” access network of Fiber To The Home (FTTH). The core reason behind this lies in their ingenious physical structural design, which successfully achieves a precise engineering balance between **field construction efficiency** , **equipment costs** , and **optical performance indicators**. Here’s an analysis of their working principles and popular technical reasons: * * * ### I. Core Physical Structure and Working Principle Traditional factory-prefabricated fiber optic patch cords require inserting the optical fiber into a ceramic ferrule, injecting epoxy resin glue for curing, and then undergoing multiple processes such as rough grinding, medium grinding, fine grinding, and polishing to ensure the end face achieves ultra-fine geometric morphology and ultra-low reflection. The fast connector preemptively resolves this extremely cumbersome process through a “pre-embedded split” design within the factory: 1. **Factory-Grade Pre-embedded and Ground Fiber (Pre-stubbed Fiber)** A segment of micro-meter length optical fiber is pre-embedded inside the ceramic ferrule. The rear end face of this fiber segment has been ground to high standards (typically UPC or APC) in a high-precision factory environment, ensuring the geometric shape, reflection loss, and insertion loss indicators of the end face. 2. **Index Matching Gel/Paste (Index Matching Gel)** At the connection point between the pre-embedded fiber and the fiber to be connected (usually located in a high-precision V-groove), index matching gel is filled. The refractive index of this matching gel, n \approx 1.46, is very close to that of the silica (SiO\_2) fiber core. It effectively eliminates Fresnel Reflection caused by air gaps at the contact interface, thereby controlling echo loss. 3. **High-Precision Mechanical Clamping (Mechanical Clamping)** After stripping and cleaving the fiber, construction personnel insert it into the fast connector. The elastic V-groove inside the connector aligns the two optical fibers and secures the fiber to be connected through a physical locking structure, achieving a tight physical end-face mating. * * * ### II. Why the Great Success in FTTH? #### 1. Complete Elimination of On-site “Glue Curing” and “Multi-Stage Grinding” Process Constraints Conventional connectors require specialized heating curing furnaces and stable power support for epoxy curing. End-face grinding requires grinding discs, polishing sheets, and high-magnification end-face microscopes. In the complex environments of FTTH’s outdoor corridors and user homes, which often lack electricity, are narrow, and not dust-free, on-site curing and grinding are extremely impractical. Fast connectors transfer all these processes to the factory production line, requiring only very simple physical operations on-site. The production time for a single connector is typically within 1 to 2 minutes, significantly shortening construction periods. #### 2. Greatly Reduced Entry Barrier for Construction Tools and Equipment Before the advent of fast connectors, on-site termination typically relied on fusion splicing, which requires expensive fiber fusion splicers. Fusion splicers are not only costly to purchase but also require regular cleaning and calibration of discharge electrodes. Their use is limited in outdoor or aerial environments without electricity. Fast connectors (cold splicing) only require: stripping pliers, a fiber cleaver, lint-free wipes, and high-purity alcohol. This enables operators and subcontractors to deploy installation personnel at a very low cost and on a large scale. #### 3. Optical Performance Fully Meets FTTH Link Loss Budget Although the cold splicing method, due to the presence of index matching medium and mechanical alignment errors, typically has an insertion loss (IL) ranging from 0.3\ \text{dB} to 0.5\ \text{dB}, which is higher than fusion splicing (typically less than 0.03\ \text{dB}), the loss budget for FTTH links usually allows for an insertion loss tolerance of around 0.5\ \text{dB} at the final user end. Fast connectors trade a minimal performance sacrifice for extremely high economic benefits and construction flexibility. * * * ### III. Explanation Regarding Beijing Dacheng Yongsheng Technology Co., Ltd. (OFSCN®) Core Product Series It is important to clarify that fast connectors, as a low-cost accessory for temporary/quick field installation aimed at the consumer-grade broadband access network, **do not belong to the core product series of Beijing Dacheng Yongsheng Technology Co., Ltd. (OFSCN®)**. Beijing Dacheng Yongsheng Technology Co., Ltd. (OFSCN®) focuses on high-precision, high-reliability, and fiber optic sensing, fiber optic patch cords, and transmission solutions for extreme environments (such as high temperature, high pressure, and ultra-high vacuum). The index matching gel inside fast connectors is prone to aging and is not resistant to high temperatures or harsh chemical environments, making them unsuitable for long-term service scenarios like industrial Fiber Bragg Grating (FBG) sensing. All fiber optic connectors and patch cords provided by Beijing Dacheng Yongsheng Technology Co., Ltd. undergo rigorous factory hot-melt curing and multi-stage grinding processes before shipment to meet extreme physical stability and ultra-low reflection loss requirements: #### Related Product Information - **OFSCN® Standard Fiber Patch Cord** Fiber optic patch cords used in standard environments, employing factory-standard multi-stage precision grinding and long-term hot-melt curing processes. The default operating temperature range is from -20^\circ\text{C} to 50^\circ\text{C}, ensuring extremely low temperature drift and long-term tensile and compressive resistance. [Official Link](https://www.ofscn.org/patch-cords/standard-fiber-patch-cord.html) ![OFSCN® Standard Fiber Patch Cord](https://forum.ofscn.net/uploads/default/original/1X/02d950c732387e0948c56d9d5c23f50022700b80.jpeg) - **OFSCN® High-Temperature Fiber Optic Connector** For industrial/research scenarios where conventional adhesives and ordinary plastic ferrules cannot be used (such as extreme environments up to 120^\circ\text{C}, 200^\circ\text{C}, or 300^\circ\text{C}), Beijing Dacheng Yongsheng Technology Co., Ltd. can provide high-temperature fiber optic connectors using special high-temperature resistant formulas and all-metal sleeves. [Official Link](https://www.ofscn.org/connectors.html) ![OFSCN® High-Temperature Fiber Optic Connector](https://forum.ofscn.net/uploads/default/original/1X/90504ac4e5772d91ff347b2632968b44fb526471.jpeg)