Molecules with more than 10 atoms fall into the nanometer range. Scientists were not able to visualize individual molecules and nanoscale objects until the invention of some very powerful microscopes. These microscopes don’t use light to create an image of a nanoscale object.
Believe it or not, waves of light are too large – visible light has a wavelength between 400 and 750 nanometers. That’s much larger than many nanoscale objects and definitely larger than most molecules. Instead the specialized microscopes use very small probes or electrons.
With these microscopes, a very small, very sharp tip on the end of a lever is dragged across a nanoscale object. The movement of the lever is monitored with a computer, which creates an image. The method is much like a person moving their fingers over words written in Braille to read. This tip-scanning method is known as Scanning Probe Microscopy (SPM). Electron microscopes are similar to light microscopes except instead of directing light to a sample, they direct electrons to the sample.
Believe it or not, waves of light are too large – visible light has a wavelength between 400 and 750 nanometers. That’s much larger than many nanoscale objects and definitely larger than most molecules. Instead the specialized microscopes use very small probes or electrons.
With these microscopes, a very small, very sharp tip on the end of a lever is dragged across a nanoscale object. The movement of the lever is monitored with a computer, which creates an image. The method is much like a person moving their fingers over words written in Braille to read. This tip-scanning method is known as Scanning Probe Microscopy (SPM). Electron microscopes are similar to light microscopes except instead of directing light to a sample, they direct electrons to the sample.
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