Security features

Holograms, microprint, UV ink, and similar physical markers that are difficult to reproduce without specialized printing equipment.

If you tilt a passport or driver's license and see a shifting image, you are looking at a security feature.

Overt and covert physical features embedded by the issuing authority for authentication. Overt features are visible to anyone, and covert features need a tool, such as a UV light, to see.

Security features are often grouped by how they are checked:

• Overt features, such as holograms, color-shifting ink, and raised printing, that a person can see and feel.
• Covert features, such as UV-reactive ink, microprint, and hidden images, that need a light or magnification.
• Forensic features, which only specialist equipment in a lab can examine.

In a photo-based check, software looks for features that a camera can capture:

1. The system identifies the document type.
2. It looks for the features that genuine documents of that type carry.
3. It checks that they look right under the lighting and angle of the capture.

Security features sit next to terms that are easy to mix up:

• Document verification is the check that inspects security features, along with layout and data.
• Counterfeit document is a fake that has to imitate these features.
• Government-issued ID is the type of document that carries them.