How do you explain a plane wavefront based on huygens' principle?

[iVenky]

Let's assume a plane wave going in the x-direction. Going by Huygens' principle, each point on the wavefront should act like a source. If that's the case, wouldn't plane wavefront become spherical like shown below? I am so confused

 

[A.T.]

Let's assume a plane wave going in the x-direction. Going by Huygens' principle, each point on the wavefront should act like a source. If that's the case, wouldn't plane wavefront become spherical like shown below? I am so confused

Have you tried a search? I found this in seconds:

From: http://sites.science.oregonstate.edu/~hadlekat/COURSES/ph212/waveOptics/single-slit.html

 

[iVenky]

Ok, I see, the wavefront touches "all" wavelets. I missed the word "all" before and that makes the difference in my understanding

Thanks.