Active Lens Structure Integrating Polarization Switching and Lenses
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing active lens structures for non-glass 3D displays face challenges in minimizing thickness and focal length, leading to issues with fill-factor, driving voltage, response speed, and aberration, particularly in mobile displays where a short focal length is required, and the separation of polarization dependent and switching sections complicates integration into mobile devices.
Innovation Solution
An active lens structure with an integrally formed polarization switching section and polarization dependent lens section, utilizing an optically isotropic polymer layer and liquid crystal phase polymer layer with 1D lattice structures for alignment, eliminating the need for a lower alignment film and glass substrate, thereby minimizing thickness and simplifying manufacturing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the polarization dependent lens section and polarization switching section are separated, then each section can be independently optimized, but the total thickness increases and integration into mobile devices becomes difficult
Solution Approach 1:
The patent merges the polarization dependent lens section and polarization switching section into a single integrated structure. The liquid crystal layer serves dual functions: it acts as the polarization switching medium between transparent electrodes while simultaneously forming the polarization dependent lens section with the optically isotropic polymer layer. This integration eliminates the need for separate sections and reduces total thickness, enabling mobile device application.
2Length of moving object
If the focal length is reduced to 1 mm or less for short viewing distance, then the display can be used in mobile devices, but the gap between display panel and lens array becomes very large
Solution Approach 1:
The patent nests the polarization dependent lens section within the polarization switching section structure. The liquid crystal layer and optically isotropic polymer layer are positioned within the same space, eliminating the need for a large external gap. The lens function is achieved through the refractive index difference within the nested layers rather than through a large physical separation.
3Adaptability or versatility
If a liquid crystal lens technique is used for 2D/3D switching, then polarization control enables mode selection, but aberration problems arise particularly at short focal lengths
Solution Approach 1:
The patent uses a composite structure combining liquid crystal material and optically isotropic polymer material. The liquid crystal layer provides polarization control for 2D/3D switching, while the optically isotropic polymer layer with its specific refractive index compensates for aberrations. This composite material approach maintains the versatility of polarization control while improving optical quality at short focal lengths.
4Length of moving object
If the gap of liquid crystal cells is increased to achieve short focal length, then the lens can be used in mobile displays, but driving voltage and response speed become large
Solution Approach 1:
The patent changes the approach from increasing gap distance (one dimension) to modifying the optical properties within the existing gap (another dimension). By adjusting the refractive index of the optically isotropic polymer layer and the alignment of liquid crystal molecules, the focal length is reduced without increasing the physical gap, thereby maintaining low driving voltage and fast response speed.
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
The integrated structure reduces the total thickness, enabling wider use in mobile displays with short focal lengths, improves manufacturing efficiency by omitting the rubbing process, and enhances alignment of the liquid crystal layer, addressing issues of fill-factor and aberration.
Implementation Method 1
photo-curable liquid crystal phase polymers are filled, 1D lattice structures (grooves) are formed on an upper surface, and the liquid crystal phase polymers are aligned along a major axis direction of the lattice structures
Implementation Method 2
a polarization switching section configured to adjust a voltage applied to selectively convert a polarization direction of incident light
Implementation Method 3
a polarization dependent lens section configured to be driven by a lens according to the polarization direction of the light incident from the polarization switching section
Implementation Method 4
an optically isotropic polymer layer having a shape of a reverse lens shape on a first surface
Data Source
AI summary
Provided is an active lens structure. The active lens structure has a configuration in which a polarization switching section and a polarization dependent lens section are integrally formed, wherein a lattice structure is formed on an upper surface of a liquid crystal phase polymer layer of the polarization dependent lens section, and the liquid crystal phase polymer layer is aligned in a top-down manner and is used as a lower alignment film of a liquid crystal layer. Therefore, the polarization switching section of the active lens structure can be fabricated without any lower alignment film and any lower glass substrate, so that it is possible to minimize the total thickness and simplifying the manufacturing process.