carried to the position C'. Here, if let the right-hand side of the 
image for the point C' be x,, and the left-hand side of the image be 
X, , we obtain ihe following N DH +X 
This is the width of the slit image from the light source in the left 
hand side\of the apparatus. In the figure 18,/ x/, x; represent the 
width of the slit image from the light source in the right hand side. 
From the figure 17, we obtain the next relation 
x ( ) m bisin ¢ 
1 sin{s(8)- fj 
bısin 9 
x,(6) - sinl e( 6) 6} 
  
  
here, 
(2e + tan0+c 
g (e) E Cos { P(8 } 
P(0) =Vc!+ a -sec’g+ 2a-c.tang (3) 
-1 4S, 
à = tan a, 
Similarly: 
x (6) s b. sin Ö N 
Br Sin 
0 = , 
x6) sin[g(o)*6] 
; .1,Q — e Lan 
p 60 = cog TR) 
  
18 the width of the slit is very small, x (8) is: 
x (a) E. Dy St 
1 = "2a - single) 
or - M. an (6) 
2 sin pe) 
Where, M is the magnifying power of the lens used in the light source. 
2 
   
   
  
   
   
   
   
  
  
  
   
   
  
    
   
   
  
  
   
    
   
  
    
    
   
  
    
    
Cn 
mn 
An 
>