Fiber Optics Institute
FO-A

FO-A · Certified Fiber Technician (Level A)

Course lessons

1 Anatomy of an optical fiber

### What a fiber really is An optical fiber is a hair-thin strand of ultra-pure glass that guides light. It has four layers you must know…

2 How light stays in the fiber

### Total internal reflection Light bends when it crosses between materials of different refractive index. When it tries to leave a dense…

3 Wavelengths, attenuation and dispersion

### The three windows Fiber is not equally transparent at every color of light. Practical systems use three infrared **windows**: **850…

4 Fiber families: OM and OS classes

### Multimode — the OM ladder ISO/IEC 11801 grades multimode fiber by bandwidth: **OM1** (62.5 µm, legacy, orange), **OM2** (50 µm,…

5 Cables: construction, ratings and color code

### How fibers become cables Bare fiber cannot be installed; cables package it for the environment. **Loose-tube** designs float 250 µm…

6 Connectors and polish types

### The big three plus one **LC** — 1.25 mm ferrule, small duplex latch; dominates transceivers (SFP/SFP+/QSFP) and high-density panels.…

7 Splicing and termination fundamentals

### Fusion splicing — the gold standard A fusion splicer aligns two cleaved fibers and welds them with an electric arc. Core-alignment…

8 Inspection and cleaning discipline

### The #1 cause of failures Industry surveys agree: **contaminated connector endfaces cause more optical failures than every other cause…

9 Basic testing: power meters and loss budgets

### The instruments of Level A **VFL (visual fault locator)** — a red laser that lights up breaks, macrobends and connector faults within a…

10 Safety: lasers, glass and the worksite

### Invisible light, real hazards Fiber systems use infrared light you cannot see or blink against. IEC 60825 classifies laser hazards;…

Exam rules

  • 100 questions, randomly drawn and shuffled per candidate
  • 120 minutes — the exam auto-submits when time ends
  • Pass mark 70% · certificate valid 3 years
  • Levels must be passed in order: A → B → C
Question bank: 3000