Level 1- Diffractive Optical Variable Image Device (DOVID)
DOVIDs protect against photocopying. DOVIDs are used as authenticity features and anti-copying protection on identity documents. When used as a laminate, they protect the personal details against forgery.
An DOVID is a pattern and/or text that displays different effects, such as movements or colour changes. DOVIDs protect against photocopying ID documents.
Most DOVIDs use diffractive optical structures to create patterns, colours and designs. The visibility of DOVIDs depends on the quantity of light falling on the DOVID or the viewing angle.
There are different types of DOVIDs, including:
- Transparent patch
- Metal patch
- Laminate: DOVIDs can be embedded in a laminate that covers almost the entire page or card surface with biographical data. In this case the transparent diffractive surface can also contain some metal inclusions to improve graphical elements that then have the feeling of a metal patch.
An example of an DOVID laminate in the Philippine passport.
The presence of different patterns and colours attracts the attention of anyone inspecting an ID document secured with DOVID functions.