Learning Forum

[johnny_hsiao]

In the script "build_S_matrix_sram.lsf". Why does the equation need to be multiplied by 1i?

The comment said "1i from diffraction". But I still don't understand. Thanks.

[Guilin Sun]

 

This is for phase correction of the fields. It will not be correct without this phase correction.

 

[johnny_hsiao]

 

So that is a phase shift of π/2 between the incident and diffracted wave. Is that right? Thanks~

 

[Guilin Sun]

yes.

If you check the Rayleigh-Sommerfeld Diffraction Integral, you will find it has a -i phase. it is forward. Now we are correcting the phase backward. I hope this helps.