A source's effect on diffraction pattern

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Aldnoahz
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I am quite aware of the effect of slit width and wavelength in a single-slit diffraction pattern. However, my teacher has never touched on the effect of a source moving towards or away from the slit. Neither can I find any satisfactory or comprehensible response to this phenomenon. While my intuition tells me that only the intensity changes, I am not entirely sure..

Could anybody discuss the effect on the diffraction pattern when a source moves away, towards, or sideways with respect to the slit? What about the effect of distance between the slit and the screen on which the wave is incident (will the diffraction pattern become wider with less intensity)?

Any explanation will be appreciated. Thanks!
 
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Aldnoahz said:
While my intuition tells me that only the intensity changes, I am not entirely sure..

In the diffraction pattern the intensity is affected by the path difference /relationship between various secondary wavelets arriving at a point on the screen - and the maxima and minima intensity is related to the intensity of illumination of the slit/hole so if someone displaces the source away/near/sideways from the slit - the illumination of the slit gets affected and the fringe width should not change.
 
drvrm said:
In the diffraction pattern the intensity is affected by the path difference /relationship between various secondary wavelets arriving at a point on the screen - and the maxima and minima intensity is related to the intensity of illumination of the slit/hole so if someone displaces the source away/near/sideways from the slit - the illumination of the slit gets affected and the fringe width should not change.

Thanks for replying. Just to clear things up, as the source moves away from the slit (no matter the direction), only intensity is affected, which decreases, and vice versa?