The description of the State Primary Standard of optical density unit GET 206-2016 is given. The principle of operation of the standard, based on filtering the luminous flux of transmitted and reflected light, is described. The composition of the standard and its metrological characteristics are presented. Data on the study of the geometric and spectral characteristics of the standard are presented. Currently, GET 206-2016 allows solving the problems of metrological support of optical transmittance density measuring instruments (radiographic non-destructive quality control of materials in various industries) and optical reflection density measuring instruments (printing, applications of energy-saving and graphic technologies).
