Missalign
Enter the Simulator →What the Simulator Does
Everything you would do at the real table — laid out, traced, and measured on screen first.
Drag-and-Drop Path Design
Place lasers, mirrors, beamsplitters, and modulators on a virtual optical bench with grid snapping and angle alignment — as intuitive as laying out a real breadboard.
Real-Time Beam Tracing
Beams propagate live along the path: every component updates the polarization state via Jones matrices and recalculates power splitting — turn a waveplate and watch the PBS ratio change instantly.
Gaussian Beam Caustic Analysis
The beam radius is tracked along the optical axis using the q parameter and ABCD matrices, marking waist positions and Rayleigh ranges — with a draggable probe to read the spot size anywhere.
3D View & Project Saving
Switch to a 3D view of the whole table with one click. Layouts can be saved in the browser, exported and re-imported, with light and dark themes for reports and discussions.
Components & How They Work
Every element in the simulator maps to real hardware on the table — its behavior is driven by the underlying physics, not by a sprite.
Laser Source
Where every path begins. Stimulated emission produces coherent light, emitted as a near-ideal TEM₀₀ Gaussian beam.
Mirrors
Dielectric multilayer coatings reflect by interference: HR mirrors reach R>99.9%, output couplers transmit a controlled fraction, and dichroics reflect or transmit by wavelength.
Polarizing Beamsplitter
A multilayer coating on the diagonal transmits p-polarized light and reflects s-polarized light, splitting one beam into two by polarization. Paired with a half-wave plate, it becomes a continuously tunable power divider.
Beamsplitters
A partially reflective coating divides the beam at a fixed ratio (50:50, 90:10, …), independent of polarization — the workhorse of pick-offs, monitoring, and interferometers.
Half-Wave Plate
A birefringent crystal delays one polarization component by π relative to the other: linear polarization is mirrored about the fast axis, so rotating the plate by θ rotates the polarization by 2θ.
Quarter-Wave Plate
A π/2 retardance: linear polarization at 45° becomes circular, and vice versa. In double pass (through, reflect, through again) it acts as a half-wave plate — the classic optical-isolation trick.
Lens
Refraction reshapes the wavefront to focus or collimate the beam. For a Gaussian beam, the new waist size and position follow from transforming the q parameter with the ABCD matrix — not from the geometric image point.
Acousto-Optic Modulator
An RF-driven sound wave creates a traveling refractive-index grating inside a crystal. The beam Bragg-diffracts off it: the first order is deflected and frequency-shifted by ±f_RF — the workhorse for fast switching, frequency scans, and power stabilization.
Electro-Optic Modulator
Based on the Pockels effect: an applied electric field changes the crystal's refractive index linearly, modulating the optical phase at high speed and adding ±f_mod sidebands to the spectrum — the heart of PDH laser locking.
Mechanical Shutter
A mechanical blade blocks the path completely — extremely high extinction, but slow (millisecond scale). It works in tandem with the AOM: the AOM is fast, the shutter closes clean.
Fiber Coupling
Sending a free-space beam into a single-mode fiber requires matching the incoming Gaussian waist to the fiber's mode field — and the efficiency is brutally sensitive to alignment. The most misalign-prone spot on any table.
Beam Dump & Power Meter
Where paths end: a beam dump safely absorbs unwanted light, while a power meter reads the optical power via photodetection — the readout you use in the simulator to verify every splitting ratio.
Under the Hood
Behind every beam on screen, two standard optical formalisms are doing the math.
A Gaussian beam's radius and wavefront curvature are packed into a single complex q parameter. Every stretch of free space, lens, or curved mirror applies its ABCD matrix to q. The simulator chains these matrices along the full path and draws the beam envelope (caustic) live — including the waist w₀ and the Rayleigh range zR = πw₀²λ.
The polarization state is a two-component complex vector (Jones vector); each waveplate, PBS, and mirror is a 2×2 Jones matrix. Every component the beam passes through multiplies the state once — so as you rotate a half-wave plate, the two PBS outputs trade power as cos²2θ / sin²2θ, exactly as on the real table.
Ready to align?
Open the virtual bench and place your first mirror.
Enter the Simulator →