Michelson interferometer simulator
Polychromatic fringes: see how arm lengths, mirror tilt, beam divergence and the light source shape the interference pattern.
Interference pattern (RGB)
Click or drag on either image to select the point used for the spectrum plot.
Phase difference
| Display |
Spectral intensity at selected point
| Source |
Interferometer
How the model works
- Purely geometric: the optical path of each arm is computed for an ideal spherical (or plane) wave; no diffraction or extended-source effects.
- The input beam is a collimated beam passed through a thin lens of the given power placed at the beamsplitter, i.e. a point source (real or virtual) 1/D from the beamsplitter. D = 0 is a collimated beam.
- Mirror 2 is tilted by θx, θy about its center, which deviates that arm's beam by twice the tilt angle.
- Spectral intensity at each pixel is S(λ)·[1 + cos(2π·OPD/λ)]/2.
- Color: the spectrum at each pixel is integrated against the CIE 1931 color matching functions, converted to sRGB, and scaled so that a fully bright fringe just reaches full scale (so brightness is relative, not absolute). Out-of-gamut colors are clipped.
- The cone responsivity curves on the spectrum plot are the L, M and S cone fundamentals (a linear transform of the same color matching functions), each normalized to a peak of 1.