Do I need to install anything?

No. It runs in any modern browser, free, with no account required.

For Engineers · Gaussian Beam

Gaussian Beam for an anti-reflective coating

Built for engineers using it for real design work. Go from concept to a running model in the browser, then scale to the cloud when needed. Simulate an anti-reflective coating live below — adjust the inputs and watch it respond, right in your browser.

Gaussian BeamLive

how a laser beam spreads

Controls

Presets

Beam waist w₀ (µm)

Wavelength (nm)

A real laser beam is not a perfect ray — it narrows to a minimum waist then spreads. Within one Rayleigh range of the waist it stays roughly collimated; beyond, it diverges at an angle set by wavelength over waist size. Tighter focus means faster spreading — the fundamental diffraction trade-off behind every laser and telescope.

▶ Run in Python

Data Inspector

Rayleigh range0.012 m

Divergence4.03 mrad

Waist50 µm

Governing equation

w (z) = w_{0} 1 + (z / z_{R})^{2}, z_{R} = \frac{π w _{0}^{2}}{λ} = 12.4 mm

Reading this result: Divergence is set by λ/(π·w₀): shrinking the waist or lengthening the wavelength both make the beam spread faster — the core diffraction trade-off.

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Frequently asked questions

Is this good for engineers?: Yes — this version of "Gaussian Beam for an anti-reflective coating" is framed for engineers using it for real design work. Go from concept to a running model in the browser, then scale to the cloud when needed.
Do I need to install anything?: No. It runs in any modern browser, free, with no account required.