Calculate diffraction angles or grating spacing for light.
Optical Parameters
nm
μm
Calculation Results
Enter parameters (θ exists if nλ/d ≤ 1)
About this calculator
Quick Reference
θDiffraction Angle
dGrating Spacing
nOrder of Maximum (integer)
λWavelength
Overview
Diffraction is the bending of waves around obstacles and the spreading out of waves past small openings. A diffraction grating uses many parallel slits to disperse light into its component wavelengths.
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Pro Tips
The grating spacing (d) is often given in 'lines per mm'. d = 1 / (lines per mm).
n = 1 is the first-order maximum, usually the brightest after the central beam.
The maximum possible value for θ is 90 degrees.
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Fun Facts
"The 'rainbow' colors you see on a CD or DVD are caused by diffraction from the tiny pits and tracks on the surface."
"Diffraction gratings are used in spectrometers to analyze the chemical composition of stars by looking at their light spectra."
