How can a surface be polished for some waves and not others?

Thread starter zachcumer
Start date Mar 10, 2008
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Surface Waves

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A surface can be polished to different degrees depending on the wavelength of the waves interacting with it. Longer wavelengths, such as microwaves, require less precision in surface smoothness, making materials like wood appear smooth to them. In contrast, visible light has a much shorter wavelength, necessitating a higher level of polish, often around lambda/20, to avoid scattering. This difference in wavelength sensitivity explains why a surface can be effective for some waves but not others. Understanding these principles is crucial for applications in optics and materials science.

Mar 10, 2008

zachcumer

[SOLVED] How can a surface be polished for some waves and not others?

The question is above...
Thanks

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Mar 10, 2008

mgb_phys

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A surface is always smoother (more polished) for a longer wavelength.
So a piece of wood is pretty smooth to 3cm microwaves but is not really lambda/20 for visible light!

Mar 10, 2008

zachcumer

thanks so much...I was thinking about writing just that but wasn't too sure.

thanks

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