Superposition Shape Images via Lenslet Grating Layers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing authentication methods for security documents and valuable articles lack sufficient protection against counterfeits and do not offer dynamic, visually appealing features that can enhance their aesthetic value.
Innovation Solution
The use of dynamically evolving superposition shape images created by the relative spatial layouts of lenslet gratings, which can be viewed in transparency mode, providing higher protection against counterfeits and allowing for authentication through recognizable messages that change with the observer's angle or location.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional printed gratings are used for authentication, then the authentication method is simple to implement, but the protection against counterfeits is insufficient
Solution Approach 1:
The authentication system is divided into multiple layers: a base layer with printed grating patterns and a overlay layer with lenslet gratings. Each layer serves a specific function - the base layer provides the underlying pattern while the lenslet overlay creates the moire effect. This segmentation allows the system to achieve high anti-counterfeit protection through the complex optical interaction while keeping individual layers relatively simple to manufacture.
Solution Approach 2:
The lenslet grating acts as an intermediary element between the base layer and the observer's eye. It modulates the light passing through the base layer to create dynamic moire patterns that change with viewing angle. This intermediary component transforms the static printed grating into a dynamic authentication display, significantly enhancing security without requiring the base layer itself to be complex.
2Manufacturing precision
If lenslet gratings are used instead of printed gratings, then the resolution and protection against counterfeits increase, but the manufacturing complexity increases
Solution Approach 1:
The lenslet grating structure incorporates dynamic characteristics where the moire pattern changes continuously with viewing angle and position. The lenslets are designed with specific focal lengths and curvature radii that create different optical paths, allowing the authentication pattern to evolve dynamically as the observer moves. This dynamic behavior provides enhanced security verification while the lenslet parameters can be standardized for manufacturing.
Solution Approach 2:
The authentication system utilizes multiple可调 parameters including lenslet focal length, curvature radius, pitch, and the relative positioning between base layer and overlay layer. By carefully selecting and controlling these parameters, the system achieves high manufacturing precision in the moire pattern while keeping individual component specifications within manufacturable ranges. The parameter optimization allows balancing between pattern quality and manufacturing feasibility.
3Adaptability or versatility
If static authentication patterns are used, then the implementation is straightforward, but the visual appeal and dynamic verification capability are limited
Solution Approach 1:
The authentication system transitions from two-dimensional static patterns to three-dimensional dynamic displays by incorporating lenslet optics. The moire patterns emerge in the third dimension of optical path space, creating depth and movement that cannot be achieved with flat printed gratings alone. This dimensional enhancement provides versatile dynamic verification while maintaining a relatively simple physical structure consisting of just two layers.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach offers strong protection against counterfeits due to the sensitivity of moire superposition techniques to layout deviations and requires sophisticated equipment for reproduction, while also providing a visually appealing and decorative feature for luxury items.
Implementation Method 1
Synthesis of superposition shape images by light interacting with superposed layers of lenslet gratings
Implementation Method 2
Authentication of documents and articles by moire patterns
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention describes methods and apparatuses for creating superposition shape images by superposed base (102,107) and revealing (101) layers of lenslet gratings. The superposition shape images form a message recognizable by a human observer or by an image acquisition and computing device such as a smartphone. The superposition shape images may be created by different superposition techniques ranging from 1D moire, 2D moire and level-line moire superposition techniques to lenticular image and phase shift superposition techniques. Moire superposition techniques enable creating superposition shape images at different apparent depth levels. Applications comprise the protection of documents and valuable articles against counterfeits, the creation of eye-catching advertisements as well as the decoration of buildings and exhibitions.