# Talk:Fraunhofer diffraction equation

## First Picture is Wrong

Both vectors r and r' should originate at the origin of the x',y' plane and the vector r' obviously cannot extend beyond the aperture, shown in that figure as a circle. In the past, there was simple derivation of the far-field equations based on the simple idea of a superposition of expanding plane waves, originating from the aperture in the x',y' plane. For unknown reasons, this derivation has since been deleted. 24.85.247.169 (talk) 08:01, 25 January 2012 (UTC) — Preceding unsigned comment added by 157.127.124.15 (talk)

the only line I need on this whole page of advanced mathematics is If the aperture is illuminated by a mono-chromatic plane wave incident in a direction {{math|l0,m0,, n0) and I have no idea what it means. I will research it and get back to you, wikipedia. Also, shouldn't this be in the "Fraunhofer diffraction" page anyway...? Schmave123 (talk) 15:17, 28 September 2011 (UTC)

I have corrected the error which you have pointed out - two"}" were missing. The parameters refer to the direction cosines of the incident wave.
The reason for keeping this page separate from the Fraunhofer diffraction page is that many wiki readers are put off by detailed mathematics, but nonetheless would like to have some understanding of the topic. On the other hand, some readers want to understand the mathematical derivations, and may even want to apply them. This is the reason for providing lots of simple examples of the application of the Fraunhofer diffraction equation.Epzcaw (talk) 11:54, 9 October 2011 (UTC)

## strange typos

Probably in hundreds of Wikipedia articles, I've seen

p312

and the like, when what was meant was

p 312

i.e. page 312. As far as I know, this never happens except in Wikipedia articles, and there, it's commonplace. I just fixed a large number of those in this article.

Is there some manual or something saying this non-standard usage should be followed? If not, why does this happen? Michael Hardy (talk) 04:22, 24 January 2012 (UTC)

This is what Wikipedia says:
"On all of these points, Wikipedia does not have a single house style. Editors may choose any option they want; one article need not match what is done in other articles. However, citations within a given article should follow a consistent style." Epzcaw (talk) 15:35, 28 January 2012 (UTC)

## Large-angle behaviour

Hi all, I've noticed in these pages that at several points the expression ${\displaystyle x/z}$ is converted into ${\displaystyle \sin \theta }$. This is a bit misleading for the following reasons: At small angle we should just say ${\displaystyle x/z\approx \theta }$, which makes things simpler. At large angles, we need to use the proper expression ${\displaystyle x/z\equiv \tan \theta }$. Using the plain ${\displaystyle \theta }$ approximation is actually MORE accurate than sine, since sine bends in totally the wrong way at large angles! — Preceding unsigned comment added by 24.85.247.169 (talk) 08:01, 25 January 2012 (UTC)

## Suggested integration of N-slit diffraction article

I have just seen this.

I agree up to a point. Fraunhofer diffraction by an N-slit grating is already given here, but maybe needs some corss-referencing. Will look at it, and put it in my sandbox.

However, the other article seems to relate mainly relate to Quantum mechanics so maybe a modified version needs to stay.Epzcaw (talk) 11:50, 4 October 2013 (UTC)

There is a detailed discussion about this on the N-slit_interferometric_equation article and there appears to be a consensus that two should no be merged. In my opinion, the other article contains no real information, just refers to some papers.
So I propose to remove the suggestion that the N-slit diffraction article is merged with this one, as it has not had any support. Please comment in the next week if you disagree. Epzcaw (talk) 16:45, 4 April 2014 (UTC)