It was just announced that the 2017 Nobel Prize for Chemistry has been

awarded to Jacques Dubochet, Joachim Frank and Richard Henderson "for developing cryo-electron microscopy for the high-resolution structure determination of biomolecules in solution".

What does the data that Cryo-electron microscopy produces when examining the structure of "biomolecules in solution" actually look like? Is it electron transmission images of the molecules, or a diffraction pattern produced by single molecules, or something different? Are the molecules still in liquid solution when they are measured, or are they actually frozen by the time the data is collected?

Including an example image or diffraction pattern or some representation of the type of data obtained from a biomolecule in solution would be greatly appreciated!

From this Nobel Prize tweet: