Demax brings 3D light-field technology to a thin single layer diffractive structure for easy and cost-effective implementation in security documents.
Light field technology represents the next generation of anti-counterfeiting solutions, offering unparalleled security and intuitive verification for passports, ID cards, driving licenses, banknotes and other high-security documents. By capturing and reproducing the full 4D light field (both intensity and direction of light rays), the technology delivers dynamic, photorealistic 3D effects that are nearly impossible to replicate with traditional printing or copying methods.
In security documents light-field technology is typically implemented using a layer of micro-lens arrays and a layer of micro-images (different perspectives of the object viewed by every micro-lens). When combined, these two layers reconstruct an enlarged image that exhibits full parallax and 3D depth.
While the two-layer system can deliver compelling visual effects, it also presents some inherent challenges for document security. The multilayer structure increases overall thickness and rigidness of the substrate and depends on highly accurate alignment between the lenses and micro-images (even minor deviations in alignment can introduce distortions or degrade the intended 3D visual performance). This requires complex manufacturing steps, which increases the risk of inconsistencies during mass production.
Demax’s E-Motion™ effect overcomes the above-mentioned drawbacks by using thin, single layer diffractive structure, where digitally computed or real scene captured micro-images are modulated with corresponding directional diffractive structures in such way that precisely preserves both the direction and intensity of light rays, allowing the reconstructed 3D object to appear with:
- Continuous, smooth parallax
- High-resolution depth
- Natural motion during tilt or rotation
- Photorealistic details
These dynamic visual cues are instantly recognisable to the human eye, providing a simple and intuitive method of verification.
The use of diffractive structures provides advanced control over spatial and frequency domains, enabling the integration of additional optical effects such as: contrast switching, image switching, and parallax swapping. The result is a visually striking, multi-dimensional feature that is not only easy to authenticate but extremely difficult to counterfeit.
Technologically benefits:
- As both layers are formed simultaneously during mastering, alignment is perfect from the start, ensuring every produced element is distortion-free and identical to the original master, something other technologies cannot guarantee.
- E-Motion effect as thin, single layer diffractive structure is easily implemented in mass production techniques for security documents and significantly reduces the production cost.