Ultrasound Physics: Beam Uniformity Coefficient

Fresh4Christ
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Pertaining to ultrasound physics, what is a "Beam Uniformity Coefficient"? How is it calculated? And why is it important? etc...

I need to write couple page paper on it and I can't seem to find any information about it anywhere...Thanks.
 
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Well, I have searched all over for information on it and cannot find anything. The only thing I have is that it is a unitless number with value of 1 or greater that describes spread of beam in space. I have googled it, looked it up in an old physics book... everything... just can't seem to figure out any of the basics. I just need pointed in the right direction, I don't need answers. Like simple stuff, how is it even calculated... why is it used... If I have that information and some resources I should be able to write a bit on it. Thanks,
 
Yeah, I googled it as well, and found very little. I wonder if it is a new and non-typical term? Thread moved to the more Advanced Physics forum, and I'll ping some Homework Help resources...
 
Thank you I appreciate it. I have looked at the Beam Uniformity Ratio (BUR) (SP/SA Factor) to see if that was related... I'm not seeing the connection. Any help is appreciated.
 
Fresh4X,

Are you studying physics of medecine or something else?
It is clear that the importance may depend on the field of application.
What is your aim with the uniform beam?

Anyway, in any field it is clear that the power profile of the beam is not totally indifferent.
In http://rheumatology.oxfordjournals.org/cgi/content/full/40/12/1331" it is clear that sharp profiles will not have the same applications as soft profiles.

From a pure physics point of view a uniform beam will show up less diffraction than a sharp beam. If diffraction is to be minimized, for example to propagate with minimum losses over long distances, then the Gaussian shape will be the best. I know that from microwave optics, but it is exactly the same for ultrasounds.

So, if you ask yourself a bit more questions, you will find more answers ...
 
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