Object: Calculate Numerical Aperture and Acceptance angle of Optical Fiber.
Apparatus Required: OFC kit with NA measurement tools, Fiber Cable.
Theory: The measurement of an optical fiber ability to collect the occurrence light ray in it is known as the numerical aperture. The short form of this is NA that illustrates the efficiency with the light which is collected within the fiber to get propagated. We know that when the light is propagated through an optical fiber during total internal reflection. So multiple total internal reflections take place within the fiber to transmit from one end to another.
Once the light ray is produced from the source of an optical fiber, then the optical fiber should be very efficient to get the maximum emitted radiation in it. So we can say that the efficiency of a light which is getting from the optical fiber is the main character once transmitting a signal throughout an optical fiber.
The numerical aperture is connected to the acceptance angle because the acceptance angle is the maximum angle during light travels through the fiber. Therefore the NA & acceptance angle is associated with each other.
Diagram:
Observation Table:
| Distance between fiber & detector, d | Radius of Circle, r | NA | Acceptance Angle |
Precations:
- Wear safety glasses
- Avoid fiber ends
- Keep hands away from face
- Have a Well-ventilated area
- Never look into the end of a fiber cable
- Use a Power Meter
- Handle Fiber Scraps Safely
- Handle Connectors Carefully
Result: We have successfully calculated NA and Acceptance angle of optical fiber.