Aircraft Cabin Light Guide Uniform Illumination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional aircraft cabin wash lighting systems using fluorescent lamps or LEDs fail to provide uniform intensity distribution along surfaces, leading to inefficient light usage and discomfort for passengers due to high intensity variations with distance, and existing LED solutions do not effectively control intensity distribution.
Innovation Solution
A light guide assembly with a longitudinal configuration and strategically placed light extraction features, calculated based on fixture angles and incident light intensity, to achieve a desired uniform or decorative intensity distribution, optimizing light usage and reducing energy inefficiencies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If fluorescent lamps are used to provide wash lighting along the ceiling, then the lighting fixtures can be positioned parallel to the aircraft centerline, but the light intensity varies dramatically with distance from the lamp surface, creating non-uniform illumination
Solution Approach 1:
The patent applies local quality by varying the density and size of light extraction features at different locations along the light guide. Specifically, the number and/or size of extraction features are adjusted based on the distance from the light source to compensate for the inverse-square law effect, ensuring uniform light distribution across the ceiling surface.
Solution Approach 2:
The patent changes physical parameters of the light extraction features (number, size, spacing) along the length of the light guide to optimize light distribution. By modifying these parameters as a function of distance from the light source, the system achieves uniform illumination despite the natural decrease in intensity with distance.
2Area of stationary object
If multiple compact lighting fixtures are positioned apart to illuminate the full cabin ceiling, then coverage is achieved, but the overlapping patterns create non-uniform light distribution and the system becomes more complex
Solution Approach 1:
The patent segments the illumination function into multiple light extraction features distributed along a single longitudinal light guide. Each segment (extraction feature) contributes to the overall illumination pattern, and their collective effect provides uniform coverage across the entire ceiling area without the need for multiple separate fixtures.
Solution Approach 2:
The patent merges multiple light extraction features into a single integrated light guide assembly that extends longitudinally along the ceiling. This consolidation provides uniform illumination across the full coverage area while eliminating the overlapping patterns and uniformity issues that arise from using multiple separate compact fixtures.
3Illumination intensity
If light extraction features are densely distributed along the light guide, then uniform illumination is achieved, but the manufacturing complexity and cost increase
Solution Approach 1:
The patent uses partial action by selectively placing light extraction features only where needed along the light guide, rather than uniformly distributing them throughout. The density and size of features are optimized based on the specific illumination requirements at different locations, reducing unnecessary manufacturing complexity while achieving uniform illumination.
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 provides a uniform and efficient illumination system that minimizes energy usage by precisely controlling light distribution, ensuring consistent intensity across aircraft cabin surfaces, enhancing passenger comfort and reducing energy consumption.
Implementation Method 1
a light guide assembly with a longitudinal configuration and strategically placed light extraction features
Implementation Method 2
calculating an incident light intensity for each of the plurality of points based on the distance and the angle of incidence
Implementation Method 3
disposing a plurality of light extraction features in a first pattern on a first unit length of the light guide
Data Source
AI summary
A method of making a light guide for an aircraft passenger cabin is provided. The method includes determining, for each of a plurality of points on an interior surface of the cabin, a corresponding fixture angle from a light fixture receptacle, a distance, and an angle of incidence at the point. The method also includes calculating an incident light intensity for each of the plurality of points, assuming a light source that emits light of uniform intensity at each fixture angle. Additionally, the method includes calculating a relative ray strength from each fixture angle needed to produce a desired incident light intensity at each corresponding point, and disposing a plurality of light extraction features on a unit length of the light guide such that at least one of a number and a size of the light extraction features are determined based on the relative ray strength for that fixture angle.