Re: features visible at low magnification are not "clear" at high magnification

On 18 Dec 2005 17:37:39 -0800, "sanjiv"
<shrivastavas@xxxxxxxxxxxxxxxxxx> wrote:

>Dear microscopist,
>
>I think i have a relatively simple problem for the experts in
>optical microscopy.
>
>I'm looking at indentation in hard ceramics [opaque material] using
>simple optical microscope with x10,x20,x50,x100 using yellow light,
>observing in reflection mode.
>
>The problem I have is at low magnification x10 around the indents a
>ring like feature is visible, however at high magnification x50 or
>x100 the features is not visible. The lateral size of the indents
>ranges from 30um to 200um. measurements by different techniques
>(AFM) the vertical depth of indents range from 2um - expected 15ums.
>The ring like features ranges in height from few(10-50) nanometers
>to about 1ums.
>
>
>I would appreciate comments, literature, references etc. explaining
>this effect.
>
>since, images can not be posted, i would gladly give images for indpeth
>response.
>
>
>thanking you for the help.
>
>Warm regards
>Sanjiv

If you can tolerate destructive action on your sample, sputter coating
with 60A Au/Pd will make the specimen look quite different under LM.

Gary Gaugler, Ph.D.
Microtechnics, Inc.
Granite Bay, CA 95746
916.791.8191
gary@microtechnics dot com
.

Relevant Pages