Message:

<p>[QUOTE=&quot;desertgem, post: 2604815, member: 15199&quot;]All systems with lens ( either glass/quartz/synthetic diamond or magnetic ( electron microscopes ) will have limitations. Light was the first and still most common medium used, then UV light with a shorter wavelength ( thus higher resolution) was used, but since humans can not see UV, it was only for photos or fluorescent screens, then electron beams ( shorter wavelengths the higher the resolution).</p><p><a href="http://zeiss-campus.magnet.fsu.edu/articles/basics/resolution.html" target="_blank" class="externalLink ProxyLink" data-proxy-href="http://zeiss-campus.magnet.fsu.edu/articles/basics/resolution.html" rel="nofollow">http://zeiss-campus.magnet.fsu.edu/articles/basics/resolution.html</a></p><p><br /></p><p>Zoom scopes change the lens spacings, and thus the magnification, but the resolution decrease as the magnification increases. Last week a store advertised a telescope with 635X, but the objective size and the focal length limited it to much lower magnification, if you wanted to see even middle size craters on the moon.</p><p><br /></p><p>In the case of SEM or even TEM, the wavelength of the beam still determines resolution. Since humans have to use a screen , photography, or electronic detectors, and in the case of SEM, an electronic beam scanning system, they also use computer type circuitry to maximize image and reduce noise of the image they present to you. When the imaged area is small ( low power) there are more true data points than when higher power is used ( similar number of data points) so interpolation ( non true data points are used), so resolution decreases.</p><p><br /></p><p>Zoom scopes which have different lens for each level ( 7-10, 10-15, 15-30) are actually more accurate, but of course more expense for the level of the scope. You might ask if the beam strength of the SEM could be raised for higher resolution, and it can in theory, until it starts causing damage to the specimen. I incinerated many specimens ( live insects) with a SEM , dead or non-organics do quite well.[/QUOTE]</p><p><br /></p>

Your name or email address:

Do you already have an account?

• No, create an account now.
• Yes, my password is:
• Forgot your password?

Stay logged in