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Young's Double-Slit Fringe Spacing Calculator

Δy = λ · L / d for fringes on a distant screen.

Compute the spacing of bright fringes in Young's double-slit experiment from the wavelength of the light, the slit separation, and the slit-to-screen distance: Δy = λ · L / d.

Dr. Helena Ortiz By Dr. Helena Ortiz
Published Last reviewed 1 min read

Inputs

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  3. Hover any result row for the underlying formula and intermediate values.

Formula

Δy = λ · L / d

In depth

Compute the spacing of bright fringes in Young's double-slit experiment from the wavelength of the light, the slit separation, and the slit-to-screen distance: Δy = λ · L / d.