Difference betweend Fizeau and Wedge Interferometry

[faofao]

Hey everybody,

I have a question concerning the difference (if any) of the Fizeau and Wedge Interferometry.

I am currently writing my thesis on a project which uses a glass wedge with air in between. This concept is fairly well discussed and background of this can be found in several textbooks and webpages.

However, I am trying to find some interesting papers, which use this type of method in a similar set-up. I have spoken with my professor and he mentioned the concept of Fizeau Interferometry. Yet isn't Fizeau Interferometry used to determin the flatness of optical plates, or is this term just used, because the fringes you get by an air wedge are similar to those obtained by Fizeau?

I really don't see connection between the two of them.

Maybe someone could enlighten me?

Many thanks,
faofao.

 

[AndyW]

Hello faofao,

Thank you for your question. Fizeau Interferometry and Wedge Interferometry are indeed related, but they have different applications and uses. Fizeau Interferometry is primarily used for measuring the flatness of optical plates, as you mentioned. This technique involves splitting a light beam and reflecting it off two surfaces, creating interference patterns that can be used to determine the flatness of the surfaces.

Wedge Interferometry, on the other hand, is used for measuring the thickness or refractive index of transparent materials, such as your glass wedge with air in between. This technique also uses interference patterns, but in this case, the patterns are created by the interference of light waves that have passed through the material at different angles.

The reason your professor may have mentioned Fizeau Interferometry is because the interference patterns created by the air wedge are similar to those obtained by Fizeau Interferometry. However, the underlying principle and application are different.

In terms of finding papers that use Wedge Interferometry in a similar set-up to your project, I suggest searching for keywords such as "wedge interferometry" or "air wedge interferometry" combined with your specific application or material. This should help you find relevant research papers.

I hope this helps clarify the difference between Fizeau and Wedge Interferometry. Best of luck with your thesis project!