^Position of maxima
^Position of maxima
Also it is found that at P for nth maxima
In a similar way the angular position of nth bright fringe is
i.e. angular positions of 1st, 2nd, 3rd maxima are
From above relation we can say that each secondary maxima occupies an angular width of 
, thus linear width of each secondary maxima is 
. As the central maxima is a spread between the angular positions 
to 
, thus its angular width is 
i.e. central maxima is twice wider than secondary maxima. Linear width of central maxi. is 
