Non-Flat Light Control Layer for Display Stray Light
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current louver films in display applications suffer from reduced luminance at edges and unwanted reflections due to fixed louver angles and pitches, which do not account for varying viewer angles across the display, limiting their effectiveness in tailoring luminance profiles for specific applications.
Innovation Solution
A non-flat light control layer with micro-louver film portions is designed to restrict light transmission based on angular profiles, allowing light to be transmitted only within a predetermined display field and restricting it outside, thereby reducing stray light and reflections by varying micro-louver angles across the film.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If uniform louver angle and pitch are used across the entire film, then manufacturing is simplified, but luminance is reduced at edges and stray light emissions increase
Solution Approach 1:
The patent applies local quality by varying the louver angle and/or pitch across different regions of the light control film. Specifically, the louver parameters are changed from uniform to non-uniform distributions, where different portions of the film have different louver angles and/or pitches tailored to the local viewing angle requirements. This allows each region to optimize luminance for its specific position in the display field.
Solution Approach 2:
The patent implements parameter changes by modifying the louver angle and/or pitch parameters across the film surface. Instead of using fixed uniform parameters, the invention varies these geometric parameters spatially to match the changing viewer angle across the display, thereby maintaining consistent luminance performance from edge to center.
2Ease of manufacture
If fixed louver angle and pitch are used, then manufacturing cost is reduced, but unwanted reflections occur from nearby surfaces
Solution Approach 1:
The patent addresses unwanted reflections by applying local quality through spatially varying louver parameters. Different regions of the film have different louver angles and/or pitches that are optimized to prevent reflections in directions specific to that region's viewing angle, thereby reducing harmful reflections without requiring complete custom manufacturing.
Solution Approach 2:
The invention uses parameter changes by varying louver angle and pitch across the film to control the angular profile of transmitted light. This spatial variation in parameters allows the film to reject light at angles that would cause unwanted reflections while maintaining manufacturability through standardized louver structures.
3Illumination intensity
If non-flat light control layer with varying micro-louver angles is used, then luminance consistency and stray light reduction are improved, but device complexity increases
Solution Approach 1:
The patent applies segmentation by dividing the light control film into multiple regions, each with different louver angle and/or pitch parameters. This segmentation allows each portion to be optimized for its specific viewing angle requirements, achieving luminance consistency across the entire display field.
Solution Approach 2:
The patent introduces another dimension by adding spatial variation to the louver parameters across the film surface. Instead of uniform two-dimensional parameters, the invention incorporates a third dimension of spatial variation in louver angle and/or pitch, enabling control of light propagation in multiple directions simultaneously.
4Use of energy by moving object
If light shaping diffusers or optical films are used, then light transmission is improved, but off-axis light suppression is insufficient
Solution Approach 1:
The patent resolves this contradiction by applying local quality through spatially varying louver parameters. Each region of the film has optimized louver angle and/or pitch that simultaneously controls light transmission and suppresses off-axis light emissions in directions specific to that region, achieving both goals without compromising either.
Solution Approach 2:
The invention uses parameter changes by varying louver angle and pitch across the film to control both light transmission and off-axis light suppression. This spatial variation in geometric parameters enables the film to maintain high light transmission while rejecting off-axis light, overcoming the limitations of conventional uniform louver films.
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 solution ensures consistent luminance across the entire display area, reducing reflections on nearby surfaces and improving visibility from different angles by aligning the direction of maximum transmittance with the design eye point, while minimizing stray light transmission.
Implementation Method 1
Micro-louver films have been used to restrict the angle at which a display may be viewed. Micro-louver films restrict the transmission of light through the use of tightly spaced, embedded louvers (which are typically black).
Data Source
AI summary
A piecewise light control layer includes a plurality of light control portions including a first light control portion and a second light control portion. The first light control portion is configured to restrict light having a first angular profile. The second light control portion is configured to restrict light having a second angular profile, wherein the first angular profile is different from the second angular profile.