Segmented NVIS Backlight with Selective LED Arrays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional NVIS compatible LED backlights face limitations such as luminance loss in daytime operation and instability at low luminance levels, and are often complex and expensive to produce, with limited supplier base and specification control for color and luminance binning.
Innovation Solution
A night vision compatible backlight design featuring a base layer with alternating arrays of openings for two sets of LED modules, one set filtered for infrared and the other unfiltered, with a diffusive reflector to provide selective energization modes for day and night vision compatibility, addressing binning and package style limitations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If all LEDs are filtered by thin film filters for NVIS compatibility, then night vision compatibility is achieved, but luminance loss occurs in daytime operation and production complexity increases
Solution Approach 1:
The backlight is segmented into two distinct sets of LEDs: unfiltered LEDs for daytime operation and infrared-filtered LEDs for night vision operation. This segmentation allows each set to be optimized for its specific operating condition, eliminating luminance loss during daytime while maintaining NVIS compatibility when needed.
Solution Approach 2:
The system dynamically switches between unfiltered and filtered LED sets based on operational requirements (daytime vs. night vision mode). This dynamic configuration allows the backlight to adapt its filtering characteristics to match the operational context, optimizing performance for each condition.
2Object-affected harmful factors
If all LEDs are filtered by thin film filters for NVIS compatibility, then night vision compatibility is achieved, but production complexity and cost increase
Solution Approach 1:
Instead of filtering all LEDs, only a portion (the second set) is equipped with infrared filters. This segmented approach reduces the total number of filters required, thereby lowering production complexity and cost while still achieving NVIS compatibility when the filtered LEDs are activated.
Solution Approach 2:
Infrared filtering is applied locally to specific LED modules that will be used in NVIS mode, rather than uniformly across all LEDs. This localized application of filtering reduces material costs and assembly complexity while maintaining the required night vision compatibility.
3Object-affected harmful factors
If filtered LEDs are used for NVIS operation, then night vision compatibility is achieved, but backlight dimming stability deteriorates at low luminance levels
Solution Approach 1:
The system changes the operational parameters by switching between different LED sets with different characteristics. The unfiltered LEDs provide stable output at low luminance levels, while the filtered LEDs provide NVIS compatibility when activated, allowing the system to maintain stability across different operating conditions.
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 solution enables efficient and cost-effective operation in both daytime and night vision environments without adversely affecting night vision equipment, improving luminance stability and reducing production complexity.
Implementation Method 1
a filtering layer positioned on a surface of the spacer layer for providing infrared filtering for the second set of LED modules
Implementation Method 2
A diffusive reflector is positioned on a surface of the filtering layer. The diffusive reflector defines apertures generally coincide with the first set of openings and the second set of openings of each array
Data Source
AI summary
A night vision compatible backlight is disclosed. The backlight may include a base layer and a spacer layer. The spacer layer defines a plurality of arrays of openings, each includes a first set of openings and a second set of openings alternately distributed along the array. The backlight also includes a first set of LED modules electronically connected to the base layer through the first set of openings and a second set of LED modules electronically connected to the base layer through the second set of openings. The backlight further includes a filtering layer for providing infrared filtering for the second set of LED modules. The first set of LED modules and the second set of LED modules may be selectively energized to provide: a first mode where the first set of LED modules are energized, and a second mode where only the second set of LED modules are energized.