Optics
Fringe Spacing
The spacing between adjacent bright (or dark) fringes in double-slit interference.
Variables
Δym
Fringe spacing
Allowed values: greater than 0
λm
Wavelength
Allowed values: greater than 0
Lm
Distance to screen
Allowed values: greater than 0
dm
Slit separation
Allowed values: greater than 0
Your notes
0/5000
Check value
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- λ = 2 m (Wavelength)
- L = 3 m (Distance to screen)
- d = 4 m (Slit separation)
Result: Δy = 1.5 m
Other optics formulas with the same quantities
- Single-Slit Diffraction (Wave Optics) shares Wavelength
- Diffraction Grating (Wave Optics) shares Wavelength
- Resolving Power of Grating (Wave Optics) shares Wavelength
- Constructive Interference Condition (Wave Optics) shares Wavelength
- Rayleigh Criterion (Resolution) shares Wavelength
Where this formula is listed
- Optics formulas, under Wave Optics, alongside Thin Film Interference and Optical Path Length.
- In the optics list it comes after Double-Slit Interference and before Single-Slit Diffraction.
- Optics formula sheet, one of 34 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Fringe Spacing formula?
Fringe Spacing is written Δy = λL/d. The spacing between adjacent bright (or dark) fringes in double-slit interference. It belongs to Optics, under Wave Optics.
What are the units in Δy = λL/d?
In SI units, Δy is fringe spacing, measured in m; λ is wavelength, measured in m; L is distance to screen, measured in m; d is slit separation, measured in m.