The Mode Field Diameter (MFD) calculator determines the fundamental mode field diameter of an optical fiber using the following formula:

$$MFD = 2a \left(0.65 + \frac{1.619}{NA^{1.5}} + \frac{2.879}{NA^6}\right)$$

Where:

• \(MFD\) is the Mode Field Diameter.
• \(a\) is the core radius of the optical fiber.
• \(NA\) is the numerical aperture of the optical fiber.

The Mode Field Diameter (\(MFD\)) is calculated by considering the core radius, numerical aperture, and the wavelength of the light used. The formula provides an estimation of the diameter of the fundamental mode in the fiber, which is crucial for understanding light propagation characteristics and optimizing fiber optic communication systems.

This calculator allows you to input the core radius in different units (nm, µm, mm) and the numerical aperture to obtain the Mode Field Diameter, which is typically expressed in micrometers (µm).