Virtual Optics Laboratory · for engineering students
A virtual optical bench where students run 22 experiments and measure what the physics predicts. Every position, blur, colour and fringe on the screen is calculated from the layout of the bench.
About the software
Students build an experiment on a virtual bench from a laser or a lamp, lenses, mirrors, slits, gratings, polarisers and a screen. The lab works out what reaches the screen from where each part stands. Move the screen out of the image plane and the image blurs. Narrow a slit and the diffraction pattern widens.
Positions, sizes, blur, brightness, colour and fringe spacing all come from the physics, never from a drawing.
The solver uses geometric rays, Gaussian beams or wave optics, depending on what is on the rail. When a setup is outside what a model covers, the lab says so.
Students record their readings, the notebook fits the straight line, and the result is compared with theory, uncertainty included.
Two editions
Both editions contain the whole laboratory. They differ in what they do with exams, so a student’s laptop never holds the answer key.
Experiments
Each experiment comes with a guide, the equations it rests on, a notebook for the readings and a demonstration that runs it for you. The numbers are the ones the app uses.
Tilt the mirror and read both angles from the protractor.
θr = θiFind the index of the second medium from how far the ray bends.
n₁ sin θ₁ = n₂ sin θ₂Find the angle where reflected p-polarised light vanishes.
tan θB = n₂ / n₁Measure the index of the glass and watch it change with wavelength.
n = sin((A + δmin)/2) / sin(A/2)Find f from the object and image distances.
1/f = 1/do + 1/diSee how image size and orientation follow the object position.
m = −di / doA broadband, extended source in an optical system.
black body, T = 2900 KMeasure a lens whose image cannot be caught on a screen.
f < 0, virtual imageFind the focal length and radius of curvature of a mirror.
f = R / 2Follow how a Gaussian beam spreads and how a lens focuses it.
w(z) = w₀√(1 + (z/zR)²)A narrower slit gives a wider pattern.
a sin θ = mλMeasure the laser’s wavelength from the fringe spacing.
Δy = λL / dMeasure the wavelength from the positions of the orders.
d sin θm = mλFind the aperture’s diameter from its first dark ring.
sin θ = 1.22 λ / DCount the fringes that pass while one mirror moves.
λ = 2Δd / NTurn the analyser and measure the light it lets through.
I = I₀ cos²θThe lens changes shape to focus near and far.
near point at 1/(A − K)Find the glasses that move the focus onto the retina.
Fs = K / (1 + dK)The near point recedes as the lens stiffens with age.
A = 18.5 − 0.30 × age (D)Two corneal curvatures, two focal lines, one cylinder to correct them.
P = (n′ − 1) / r per meridianThe eye focuses blue light in front of red.
0.85 D between 486 and 656 nmRays through the edge of the pupil focus in front of those near the axis.
n sin i = n′ sin i′, traced exactlyWeb lab
The web lab has all 22 experiments, the guides and the notebook, and needs no installation. Exams run only in the Windows app, because the classroom works over the local network.
Download · latest release
For 64-bit Windows 10 and 11. The installer needs no administrator rights and opens exam files with a double-click. The portable file runs without installing anything.
The laboratory, writing exams, the classroom and marking.
VirtualOpticsLab-Teacher-…-setup.exeThe laboratory, joining and sitting exams.
VirtualOpticsLab-Student-…-setup.exeThe files are not code-signed, so Windows SmartScreen asks once before the first start. Choose More info, then Run anyway.
All versions on GitHub