Single-Slit Diffraction

Theory

Diffraction is strong when the opening $a$ is comparable to $\lambda$. The first minimum is at $a\sin \theta =\lambda$.

What to observe

• With $a=1.6$ m and $\lambda =1$ m, the beam spreads ≈ 39° to each side.

Try this

• Widen the slit: the wave passes almost straight.
• Lower the frequency (larger λ): more diffraction.

Also available in: Difração em fenda simples (Português) · Difracción por una rendija (Español)