Re: Dr.T's assertion

[T3D John W Roberts <roberts@xxxxxxxxxxxxxxxxx>]

John Bercovitz writes:

>John Vala writes:
>[description of SEM operation; all new to me]

>> I can't see any element along the way
>> that would act as a "lensing" element which we could apply to standard
>> geometric optics. 

>How about the electron gun?  Is the beam steered from essentially a 
>point source?  If it is, isn't that the moral equivalent of a lens with
>focal length the distance of the "point source" to the sample?

>John

How about the distance from the subject to the pickup?

John


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