How do I simulate a laser beam?

Open this page and use the live Laser Cavity tool below — set your inputs and the simulation runs instantly in your browser using real numerics. No install, no account needed.

Yes. The simulation runs free in your browser. A one-time unlock or a Pro plan adds advanced parameters, saved presets, data import, and clean exports.

Can I use my own numbers?

Absolutely — every input is adjustable, and with data import you can drive a laser beam from your own measurements.

Use case · powered by Laser Cavity

Laser Cavity for a laser beam

Simulate a laser beam live in your browser. This runs the real Laser Cavity solver — adjust the inputs, watch it respond instantly, and export the result. No install, no account.

For:Students Researchers Educators Engineers Hobbyists & Makers K-12 Students First Responders

Laser CavityLive

gain, loss & threshold

Controls

Presets

Pump power

Cavity loss

A laser fires only when the optical gain from the pumped medium exceeds the losses of the mirror cavity. Below that threshold it merely glows like a lamp; above it, stimulated emission takes over and output rises steeply and linearly with pump power. This sharp threshold is the defining signature of laser action.

▶ Run in Python

Data Inspector

Threshold2.0

Output power1.60

Statelasing

Governing equation

P_{out} = 0.8 max (P_{pump} - P_{th}, 0) = 0.8 max (4 - 2.0, 0) = 1.60

Reading this result: Well above threshold, output climbs almost linearly with pump; the slope (~0.8 here) is the slope efficiency, and lowering cavity loss shifts the whole knee left.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

or unlock everything with Pro →

About this simulation

The full Laser Cavity tool models a laser beam with the same numerics engineers and scientists use — running entirely client-side. Change any parameter and the result updates in real time, so you can build intuition, check a design, or teach the concept without spreadsheets or installs.

More you can do with Laser Cavity

Laser Cavity for a camera lens Laser Cavity for a fiber-optic cable Laser Cavity for a microscope Laser Cavity for a telescope Laser Cavity for a prism Laser Cavity for a rainbow Laser Cavity for a hologram Laser Cavity for a solar cell

Other ways to simulate a laser beam

Snell's Law for a laser beam Diffraction Grating for a laser beam Curved Mirrors for a laser beam Prism Dispersion for a laser beam Fiber Optics for a laser beam Gaussian Beam for a laser beam

Frequently asked questions

How do I simulate a laser beam?: Open this page and use the live Laser Cavity tool below — set your inputs and the simulation runs instantly in your browser using real numerics. No install, no account needed.
Is it free?: Yes. The simulation runs free in your browser. A one-time unlock or a Pro plan adds advanced parameters, saved presets, data import, and clean exports.
Can I use my own numbers?: Absolutely — every input is adjustable, and with data import you can drive a laser beam from your own measurements.