In Fraunhofer diffraction,draw the graph of the intensity of light on the screen versus the diffraction angle $\theta$ and write its characteristics.

(N/A) In Fraunhofer diffraction,the graph of the intensity of light on the screen versus the diffraction angle $\theta$ is shown in the figure.
From the graph,it can be observed that the intensity of the central maxima is the highest.
$(i)$ All minima have zero light intensity.
$(ii)$ The intensity of the secondary maxima decreases as the angle of diffraction increases. Thus,the intensity decreases as the order increases,and the width of the maxima also decreases.
$(iii)$ As the ratio $\frac{\lambda}{a}$ is small,the diffraction effect is less,and if it is large,the diffraction effect is more.