Physics Explanation

Single slit diffraction occurs when light passes through a narrow opening and spreads out. According to Huygens' principle, each point on the wavefront at the slit acts as a new source of spherical wavelets. These wavelets interfere with each other, creating the diffraction pattern.

The condition for dark fringes (minima) is given by:

a sinθ = mλ (where m = ±1, ±2, ±3, ...)

Where:

• a = slit width
• θ = angle from central axis
• λ = wavelength of light
• m = order of the minimum

The central maximum is twice as wide as the secondary maxima and much more intense. The intensity falls off rapidly with increasing angle from the center.