# Fiber Refractive Index Profile

**URL:** <https://forum.ofscn.net/t/fiber-refractive-index-profile/429>\
**Category:** OFSCN Technical Knowledge Base\
**Tags:** fbg-technology, specialty-fiber, wiki-component\
**Created:** [January 25, 2026, 2:46am UTC](https://forum.ofscn.net/t/fiber-refractive-index-profile/429 "2026-01-25T02:46:07Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![frostweaver](https://forum.ofscn.net/letter_avatar_proxy/v4/letter/f/da6949/32.png) [@frostweaver](https://forum.ofscn.net/u/frostweaver)\
**Post date:** [January 25, 2026, 2:46am UTC](https://forum.ofscn.net/t/fiber-refractive-index-profile/429/1 "2026-01-25T02:46:07Z")

</div>

What is the difference between Step-Index and Graded-Index fibers?

---

<div class="post-metadata">

**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:** [January 25, 2026, 2:46am UTC](https://forum.ofscn.net/t/fiber-refractive-index-profile/429/2 "2026-01-25T02:46:14Z")

</div>

Step-Index and Graded-Index fibers differ primarily in their core’s refractive index profile, which affects how light propagates through them and, consequently, their transmission characteristics.

1. **Step-Index Fiber:**

2. **Graded-Index Fiber:**

Here is a general image of an optical fiber:

 ![85-fiber](https://forum.ofscn.net/uploads/default/original/1X/6a319a4dd5ea0f7c0cc52e7310cea412ad0410b5.jpeg)  
OFSCN offers various types of optical fibers, including those typically used for single-mode (step-index) applications such as [OFSCN® G.652D Optical Fiber](https://www.ofscn.org/optical-fibers/g-652-d.html), and multi-mode fibers like [OFSCN® 300 MM Polyimide Optical Fiber](https://www.ofscn.org/optical-fibers/polyimide-coated-mm-300.html), which often employ a graded-index profile for optimal performance.