I. Hypothesis → II. Experiment → III. Proof

Section § 42 — Wave Optics · Michelson Interferometer & Optical Path Difference Δ = 2 Δd t = 0.00 s

Michelson Interferometer & Phase Shift of Beams

Displacing a mirror by merely half a wavelength of light reverses the central interference fringe from bright to dark.

Prediction Problem

By what distance \Delta d must the movable mirror M_1 of a Michelson interferometer be translated for the interference pattern on the screen to shift by exactly one full fringe (\Delta m = 1)?

Your hypothesis: Option B

In the arm with movable mirror M_1, the light beam travels from the beam splitter to the mirror and back again. Moving the mirror by \Delta d therefore changes the round-trip optical path difference by \Delta = 2\Delta d. Shifting by one full fringe requires 2\Delta d = \lambda, or \Delta d = \lambda/2.

Analytical Law Formula

System Energy Balance E = 0.0 J

Kinetic E_k

0.0 J

Potential E_p

0.0 J

Heat Q

0.0 J

Fig. 42.1 — Optical layout of the Michelson interferometer with beam splitter BS, mirrors M₁, M₂, and concentric Haidinger rings

Fundamental Relations Theory

Apparatus Parameters

Diagram Overlays

Force & Velocity Vectors Vector Symbol Labels Trajectories & Guide Lines Wavefronts & Thermal Particles

Velocity ($\vec{v}$)

Momentum / Projections

Gravity ($m\vec{g}$)

Normal / Tension / Pressure