INFRAREDESIGN NA POŠTANSKIM MARKAMA INFRAREDESIGN ON POSTAGE STAMPS Jana Žiljak Vujić Sažetak Dizajn poštanske marke izrađen je sa INFRAREDESIGN® zaštitom. Kvaliteta sakrivanja infracrvene grafi ke, dokazuje se sa spektrima bojila u rasponu od 400 do 900 nanometara. Z grafi ke se ne vide golim okom ali se raspoznaju RGB Z kamerom. Sastav bojila je određen po IRD algoritmu. U radu su prikazana dva tona boja: crveni i plavi svaki u dva stanja. Blizanci njihovih spektra su jednaki u V spektru, a oni se razdvajaju se nakon 700 nm. Spektri oba tona boja se spajaju nakon 800 nm ali tako da spektri različitih boja imaju jednaku vrijednost u Z prostoru. Spajaju se spektri plavog i crvenog bojila: posebno za nevidljive Z grafi ke te posebno za grafi ke čije Z vrijednosti su jednake nuli. Spektri bojila, mjerenje spektra, koriste se sa smislom da provjerimo IRD sustav sakrivanja grafi ka. Poštanska marka je pokazana u njenom vizualnom dizajnu te u skeniranoj slice s blokiranjem na 780 nm. KLJUČNE RIJEČI: INFRAREDESIGN, POŠTANSKA MARKA, SPEKTRI TISKARSKIH BOJILA Abstract Design of stamps is made with INFRAREDESIGN® protection. Th e quality of hiding infrared prints, proves the spectrum of dyes in the range of 400–900 nanometers. Z graphics are not visible to the naked eye but they are distinguished with RGBZ camera. Th e composition of dyes is determined by the IRD algorithm. Th e paper presents the two-tone colors: red and blue each in two states. Twins of their spectrum are equal in V spectrum, and they are separated after 700 nm. Th e spectrum of the two tone colors are combined after 800 nm but so that spectrum of diff erent colors have the same value in Z space. Combine the spectrum of the blue and red dyes: especially for invisible Z graphics and especially for graphics whose Z values are equal to zero. Th e spectrum of dyes, measuring range, are used with the sense to check the IRD system of hiding graphics. Th e postage stamp is shown in its visual design and in the scanned image with blocking at 780 nm. KEYWORDS: INFRAREDESIGN, POSTAGE STAMP, PRINTING DYES SPECTRA |