Why Do Some Diffraction Orders Go Missing?

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Missing orders in diffraction occur when the interference and diffraction patterns overlap, causing certain diffraction maxima to disappear. The interference pattern displays intensity maxima uniformly, while the diffraction pattern follows a sinc function, which approaches zero at specific points. When the zeros of the sinc function coincide with the maxima of the interference pattern, those orders are not visible. The phenomenon is influenced by the distance between the slits for interference and the width of the slits for diffraction. Understanding this interaction is crucial for analyzing diffraction patterns in experiments.
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Explain the concept of missing orders in case of double and n slit diffraction.
 
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We say that an order of diffraction is missing if it disappears as a consequence of the overlapping of the interference and the diffraction patterns.

On a screen, intensity from interference has all its maxims at the same level (like a cosine), while intensity for diffraction goes like a sinc (sin(x)/x), so that it gradually tends to 0. The sinc has several zeros (when sin(x)=0 except from x=0), and if one of these zeros overlaps a maximum of interference, we see nothing.
So, there is missing order.

Interference depends on the distance between the slits, while diffraction depends on the width of the slits.

For more info, you can read http://en.wikipedia.org/wiki/Double_slit
 
We say that an order of diffraction is missing if it disappears as a consequence of the overlapping of the interference and the diffraction patterns.

On a screen, intensity from interference has all its maxims at the same level (like a cosine), while intensity for diffraction goes like a sinc (sin(x)/x), so that it gradually tends to 0. The sinc has several zeros (when sin(x)=0 except from x=0), and if one of these zeros overlaps a maximum of interference, we see nothing.
So, there is missing order.

Interference depends on the distance between the slits, while diffraction depends on the width of the slits.

For more info, you can read http://en.wikipedia.org/wiki/Double_slit
 

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