The vacuum chamber containing a set of electrodes through which a current can be passed to heat a metal foil placed between the electrodes. The heated metal evaporates, and atoms from it coat the specimen lying below the electrodes. The coating is cast at an angle, and as a consequence the specimen appears in relief when viewed under the electron microscope. A vacuum evaporator equipped with graphite electrodes is also employed to prepare the carbon films that sometimes are used to support ultrathin sections on specimen screens. See shadow casting.
Subjects: Genetics and Genomics.