The example of appearance of 12 hidden images at the background of the main image.

The main image:

The image may be printed out either on the paper or on the other surface. The color model CMY. The hidden images are coded in the layers CYAN and MAGENTA. The enlarged fragment of the raster:

A special optical key, usually in the shape of the covering film, is used for development of the hidden images. 12 different hidden images in turn get developed as the result of turning the key.

Angle 7,5 deg.

Angle 22,5 deg.

Angle 37,5 deg.

Angle 52,5 deg.

Angle 67,5 deg.

Angle 82,5 deg.

Angle 97,5 deg.

Angle 112,5 deg.

Angle 127,5 deg.

Angle 142,5 deg.

Angle 157,5 deg.

Angle 172,5 deg.

Patent WO2008100172