FIELD: printing industry; printing important papers. SUBSTANCE: information medium has at least one half-tone reproduction formed by structural elements each of which has base geometry and size which defines level of brightness of half-tone reproduction which has at least two adjacent sections; each section includes preset number of structural elements; number of structural elements of two adjacent sections per area unit is different and/or structural elements of at least two adjacent sections are shifted relative to each other. Method of production of information medium, important document in particular, half-tone reproduction of original copy is divided into at least two adjacent sections. Definite number of structural elements is selected for each section of half-tone reproduction per area unit at different number of structural elements per area unit on at least two sections. Size of structural elements at each section is selected depending on section of half-tone reproduction found on it. Half-tone reproduction is applied on document on at least two sections with definite number of structural elements for each section whose sizes correspond to sections of half-tone reproduction. EFFECT: enhanced protection against forgery due to structure forming watered effect in taking copies. 22 cl, 5 dwg
