Microlens Sheeting Floating Composite Images
Solution Overview
Problem
Existing sheeting technologies that create three-dimensional images are complex, require multiple exposures, and are ill-suited for producing images of virtual objects, with images only viewable from a limited angle and needing illumination from the viewing side.
Innovation Solution
A microlens sheeting that forms composite images within a single layer of material, allowing images to appear suspended above, below, or in the plane of the sheeting, without requiring an adjacent layer, using microlenses that focus collimated light to create images that can be viewed from both sides and appear to float or move with the observer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If integral photography method is used to produce three-dimensional images, then the image depth perception is improved, but the device complexity and manufacturing complexity increase significantly due to multiple exposures and multiple cameras required
Solution Approach 1:
The patent divides the imaging function into multiple microlenses arranged in an array, where each microlens captures a different perspective of the object. This segmentation replaces the need for multiple cameras while achieving the same three-dimensional imaging effect through spatial division of the optical function.
Solution Approach 2:
The patent uses a single camera to capture multiple images simultaneously through the microlens array, creating multiple virtual images that represent different viewing angles. This copying approach eliminates the need for multiple physical cameras while preserving the three-dimensional imaging capability.
2Illumination intensity
If retroreflective sheeting with microlenses is used to form images, then the image brightness is improved, but the viewing angle becomes very limited
Solution Approach 1:
The patent transitions from a two-dimensional image plane to a three-dimensional image space by positioning images at different depths within the sheeting material. This dimensional change allows viewers to see the image from multiple angles while maintaining brightness, as the image exists in volumetric space rather than a flat plane.
Solution Approach 2:
Different regions of the sheeting contain images at different depths and orientations, allowing each local region to optimize for its specific viewing direction. This local quality variation enables wide overall viewing angles while maintaining bright images in each directional sector.
3Stability of the object's composition
If conventional integral photography is used, then three-dimensional image effect is achieved, but the method is ill-suited for producing images of virtual objects since it requires a real object before the camera
Solution Approach 1:
The patent introduces a microlens array as an intermediary optical element that can capture light from virtual objects (such as computer-generated images or projections) and form three-dimensional images without requiring a physical object. The microlens array mediates between the virtual image source and the camera sensor, enabling 3D imaging of non-physical objects.
4Stability of the object's composition
If multiple layers of microlenses and material are used, then the floating image effect is improved, but the device complexity and manufacturing difficulty increase
Solution Approach 1:
The patent combines multiple functional layers (microlenses, image-forming material, and spacing structures) into an integrated single-layer sheeting construction. This merging eliminates the need for separate alignment of multiple layers during manufacturing, reducing complexity while maintaining the floating image effect through internal optical path design.
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
Enables the creation of tamperproof, secure images in various applications like security documents and identification cards, with improved viewing angles and flexibility, as the images can be observed with the unaided eye and appear to float or move, enhancing security and visual appeal.
Implementation Method 1
The energy of the incident light impinging upon the microlens sheeting is focused by the individual microlenses to regions within the sheeting
Implementation Method 2
microlenses have refractive surfaces that transmit light to positions within the layer of material
Data Source
Figure 1~3
Figure 4
Figure 5
AI summary
Translucent, transparent, or semi-translucent microlens sheetings with composite images are disclosed, in which a composite image floats above or below the sheeting, or both. The composite image may be two-dimensional or three-dimensional. The sheeting may have at least one layer of material having a surface of microlenses that form one or more images at positions internal to the layer of material, at least one of the images being a partially complete image. Additional layers, such as retroreflective, translucent, transparent, or optical structure layers may also be incorporated into the sheeting.