Latent Image PEAK®
(PEAK — Printed and Embossed Anti-Copy Key, developed by Giesecke+Devrient)
An image is formed by two types of lines that are combined during the printing process: 1) parallel lines applied by blind embossing 2) one-color parallel lines of the background applied by offset printing. At a right angle of observation and illumination, the latent image PEAK® is almost invisible. When viewed in sliding light, the lines of the background are visualized on the ridges of relief lines applied by blind embossing and form the latent image PEAK®.
Fig. 1. Scheme of observing the latent image PEAK®
a
b
c
d
e
Fig. 2. Kosovo. Diplomatic passport issued in 2008:
a — front endpaper. Paper substrate; b — the same. Area with the latent image PEAK®. Viewed at a right angle of observation and illumination; c — the same. Zoomed fragment. The word KOSOVO is applied by blind embossing. The background (blue lines) is applied by offset printing; d, e — the same. Viewed at different angles of observation and illumination