This invention relates to methods of writing and reading information hidden
from visual observation and may be used for visualizing hidden images (marks) identifying
an object, which provide protection from unauthorized reproduction (forgery). The
method of creation and visualization of an optically invisible mark consists in
the following. On the surface of the object in question an optically invisible
marking image is formed by means of modification of, at least one part of said
surface, after which visualization of said image is established. Prior to formation
of the optically invisible marking image the surface of the object in question
(carrying the applied image) is made into a mirror. Modification is achieved by
changing the surface energy of the parts being modified. In addition the visualization
of the optically invisible marking image is achieved by means of establishing in
the area of said surface of the object in question a meta-stable environment, by
means of which the visually observed image of the optically invisible mark is obtained
as differences of the structures, which are formed by particles of the stable phase
of the meta-stable environment, on parts of the surface (of the object in question)
with different surface energy. Different variants regarding the use of meta-stable
environments, as well as methods of formation, on the surface of a object in question,
of an optically invisible marking image are provided.
