circ_screen - filters the field through non-transparent circular screen.

Calling Sequence

[field_out]=circ_screen(field_in,R[,x_shift[,y_shift]])

Parameters

• field_in :input field.it must be diffractive wavefront.
• R : the radius of the aperture in meters.
• x_shift : the shifts of the X direction in meters(zero is defaulted).
• y_shift : the shifts of the Y direction in meters(zero is defaulted).
• field_out : the output field or diffractive wavefront.

Description

filters the field through a non-transparent circular screen of radius R given as the first argument. Two optional arguments define the decentering of the aperture in X and Y directions

Examples

	m=1;
	nm=1e-9*m;
	mm=1e-3*m;
	cm=1e-2*m;

	lambda=550*nm;
	sizes=5*mm;
	
	F1=begin(sizes,lambda);

	F2=circ_screen(F1,sizes/2);
	dwf_fits(F2,"F2");	
	
	F3=circ_screen(F1,sizes/4,sizes/4);
	dwf_fits(F3,"F3");	
 

Author

Chen jingyuan, Gan guangyong (IAPCM, Beijing,China.)

See Also

circle ,   circ_ap ,   rect_screen ,   gauss_screen ,