When Is an Image Not an Image?

Abstract

The challenge is to tell the truth. In the world of nano this is not as easy as it sounds. Take, for example, the question of images claimed to represent what some nano configuration or another looks like. It is alleged Scanning Tunneling Electron Microscopes (STEMs henceforth) produce such images. Let’s rehearse what happens: According to Rasmussen and Hawkes: … an electron beam that is small compared with the imaged area passes over the specimen in a regular pattern, and a picture of the specimen surface is reconstructed on a video tube… interaction of the beam with the specimen produces varying intensities of backscattered and secondarily released electrons for each position in the scan, and these are registered by a detector placed appropriately near the specimen… All electron microscopes depend on the capacity of magnetic and electric fields to alter the path of electron beams according to the laws of optics (1998, p. 383).