For Educators · Fiber Optics
Fiber Optics for a waveguide
Built for educators teaching it to a class. Drop a live demo into a lecture or assign it as a shareable link — no lab installs. Simulate a waveguide live below — adjust the inputs and watch it respond, right in your browser.
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total internal reflection
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An optical fiber traps light in a high-index core surrounded by lower-index cladding: rays hitting the boundary above the critical angle undergo total internal reflection and bounce down the fiber for kilometers. The numerical aperture sets the acceptance cone, and the core size decides whether it carries one mode (single-mode, for long-haul) or many (multimode).
Data Inspector
Critical angle80.6°
Numerical aperture0.242
Acceptance angle14.0°
Fiber typemultimode (~423)
Governing equation
Reading this result: Rays steeper than the 80.6° critical angle reflect and stay trapped; here V = 29.1 allows ~423 modes, so this behaves as multimode fiber — cheap and easy to launch, but modal dispersion caps the bandwidth.
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- Is this good for educators?
- Yes — this version of "Fiber Optics for a waveguide" is framed for educators teaching it to a class. Drop a live demo into a lecture or assign it as a shareable link — no lab installs.
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- No. It runs in any modern browser, free, with no account required.