Diffraction Grating Calculator
Calculate diffraction angles from grating spacing and wavelength.
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Enter the slit spacing in meters, the wavelength in meters, and the diffraction order. The calculator shows the diffraction angle in degrees and radians, plus the maximum observable order.
About Diffraction Grating
A diffraction grating produces multiple beams of light by diffraction and interference. Each order corresponds to a different angle where constructive interference occurs. The grating equation d sin(theta) = m lambda relates slit spacing, angle, order, and wavelength. Diffraction gratings are essential in spectroscopy for separating light into wavelengths, allowing analysis of atomic emission spectra, laser wavelengths, and optical communications.
Frequently Asked Questions
What is a diffraction grating?
A diffraction grating is an optical element with many parallel slits or grooves that splits light into its component wavelengths. It works by the interference of light waves passing through the slits.
What determines the diffraction angle?
The angle depends on the wavelength, slit spacing, and diffraction order. The equation d sin(theta) = m times lambda gives the angle for order m.
What is the maximum diffraction order?
The maximum order is the largest integer m for which sin(theta) is less than or equal to 1. It equals floor(d / lambda).