# What is optical fiber "splicing"?

**URL:** <https://forum.ofscn.net/t/what-is-optical-fiber-splicing/2817>\
**Category:** OFSCN Technical Knowledge Base\
**Tags:** fbg-technology\
**Created:** [September 11, 2026, 5:17am UTC](https://forum.ofscn.net/t/what-is-optical-fiber-splicing/2817 "2026-09-11T05:17:37Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![VoidWalker](https://forum.ofscn.net/letter_avatar_proxy/v4/letter/v/848f3c/32.png) [@VoidWalker](https://forum.ofscn.net/u/VoidWalker)\
**Post date:** [September 11, 2026, 5:17am UTC](https://forum.ofscn.net/t/what-is-optical-fiber-splicing/2817/1 "2026-09-11T05:17:37Z")

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Two glass fibers broke, can I glue them? Why do you need to use high voltage to electrocute it?

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**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:** [September 11, 2026, 5:19am UTC](https://forum.ofscn.net/t/what-is-optical-fiber-splicing/2817/2 "2026-09-11T05:19:28Z")

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In optical fiber engineering and fiber optic communication, the requirements for connecting optical fibers are fundamentally different from those for ordinary mechanical parts. The core function of optical fiber is to transmit optical signals with low loss and minimal distortion.

* * *

### I. Why can’t two broken optical fibers be directly glued together?

An optical fiber is not an ordinary solid glass thread but a precision micro/nano optical waveguide composed of a **core** and a **cladding**. Taking standard single-mode fiber as an example, its outer diameter (cladding) is typically 125\ \mu\text{m} (approximately the thickness of a strand of hair), while the **core diameter that actually transmits optical signals is only about 9\ \mu\text{m}**. Gluing fiber optic cables has the following fundamental defects at both physical and optical levels:

1. **Mode Field and Axial Alignment Tolerance (Sub-micron Requirements)**:

2. **Refractive Index Mismatch and Fresnel Reflection** :

3. **Environmental Adaptability and Long-Term Aging** :

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### II. Why is “high-voltage electricity” (arc discharge) used for fusion splicing?

Optical fiber “fusion splicing” is a process that uses the **high temperature generated by arc discharge** to melt and re-join the glass end faces of two optical fibers into one.

```auto
       High-Voltage Electrode (+)
           ▼
Fiber End Face ──▶ 💥 ◀── Fiber End Face (Discharge area forms a plasma high-temperature zone of 1600℃~2000℃)
           ▲
       High-Voltage Electrode (-)

```

1. **Achieving Atomic-Level Continuity of Material Interface (High-Temperature Fusion)**:

2. **Self-alignment via Surface Tension in a Molten State** :

3. **Excellent Optical and Mechanical Performance** :

* * *

_Note: Optical fiber fusion splicers and fiber cleavers are common tools for fiber optic construction and laboratory assembly and are not part of Beijing Dacheng Yongsheng Technology Co., Ltd.'s (OFSCN®) core product lines._