near_fresnel - propagate wavefront using near field fresnel propagator.

Calling Sequence

[dwf_out]=near_fresnel(dwf_in,distance)

Parameters

• dwf_in :input field. it must be diffractive wavefront.
• distance :the propagating distance in meters.
• dwf_out : the output field or diffractive wavefront.

Description

Propagate using near field fresnel propagator (the paraxial approximation for the angular spectrum) it's a replacer of fresnel . This function is an approximate form for the near_angular

Examples

	f1=begin(0.02,1e-6,128);
	f2=circ_ap(f1,0.005);
	f3=near_fresnel(f2,1);
	field_plot(f3);
 

Author

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

See Also

fresnel ,   forward ,   steps ,   geom_propagation ,   near_angular ,   far_fraunhoffer ,   far_fresnel ,   fraunhoffer_grt ,   fresnel_grt ,   propagate ,