Is diffraction related to wavelength?

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Pfalzheimt3uj · Accepted Answer

Light bends when it crosses a boundary between two different mediums, each with a different index of refraction.
Diffraction, on the other hand, occurs when light bends in the same medium. Light waves bend as a result of "squeezing" through small openings or "curving" around sharp edges.
Since light waves are small (on the order of 400 to 700 nanometers), diffraction only occurs through small openings or over small grooves. Moreover, waves diffract best when the size of the diffraction opening (or grting or groove) corresponds to the size of the wavelength. Therefore, light diffracts more through small openings than through larger openings.
The formula for diffraction shows a direct relationship between the angle of diffraction (theta) and wavelength:

d (\sin θ) = m (wavelength) \to for constructive interference

(A similar formula for destructive interference exists.)
From either formula, however, it's clear that as the wavelength increases, the angle of diffraction increases, since these variables are on opposite sides of the equal sign.
Conversely, as the wavelength decreases, the angle of diffraction decreases.
In short, the angle of diffraction is proportional to the wavelength size.
Thus, red light (long wavelength) diffracts more than blue light (short wavelength). And radio waves (really long wavelength) diffract more than X-rays (really short wavelengths).

Is diffraction related to wavelength?

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