Double-slit interference
Δx = λL/d — animated fringe pattern on a screen.
OpticsSnell’s law, TIR, interference and diffraction.
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Double-slit interference
Double-slit fringes follow Δx = λL/d; bright fringes need path difference mλ.
Double-slit: coherent waves interfere into fringes.
Key formulas
\Delta = d\sin\theta\text{bright: }\Delta=m\lambda
How to use
- Tune slit spacing d and wavelength λ.
- Watch fringe spacing change on the screen.
- Relate the pattern to Δx = λL/d.
Applications
- Double-slit interference: Double-slit: coherent waves interfere into fringes.
- In class, tune parameters for “Double-slit interference”, then check against the textbook result.
FAQ
What if wavelength increases?
Fringes spread farther apart when other parameters stay fixed.
What does MVP mean on this page?
An interactive sketch with formulas and parameters. Polished Ready labs are the full bench experience.
What does the “Double-slit interference” lab practice?
Tune parameters and match readouts to the “Double-slit interference” relations — useful for prep and demos.
Real vs virtual image?
Real images can form on a screen; virtual ones cannot — view by eye along rays.