Uniform Illumination in LED Signage via Reflective Cage Structure

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing lighting devices for small-sized illuminated signs, such as letters or numbers, face challenges in achieving uniform luminance due to limited space for light diffusion, and existing solutions are either costly or require high precision in component mounting.

Innovation Solution

A lighting device employing an 'umbrella' concept with a light-reflective substrate, a light-permeable cage structure, and a highly reflective cover layer to diffuse light uniformly, allowing for simple manufacturing and protection against external agents, while maintaining optical coupling without critical aspects.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If complex optical solutions with light guides and shaped reflective elements are used, then uniform illumination is achieved, but manufacturing costs increase and precision mounting is required

Engineering Contradiction:

Improveuniform illuminationVSAvoidoptical components

Core Design Contradiction:

Illumination intensityVSDevice complexity

Solution Approach 1:

The invention extracts and eliminates complex optical components (light guides, shaped reflective elements) from the lighting device, retaining only the essential light source and housing structure. This simplification maintains uniform illumination through proper geometric design rather than complex optics.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

Instead of using complex optics to shape and distribute light, the invention inverts the approach by using the housing geometry itself to achieve uniform light distribution. The simple housing structure with properly positioned light sources creates the desired illumination pattern without additional optical elements.

Inventive Principle:

Principle #13The other way round (Inversion)

2Illumination intensity

If reflectors are used instead of reflective materials, then lighting coverage is improved, but minimum distance requirements limit applicability to small surfaces

Engineering Contradiction:

Improvelighting coverageVSAvoidminimum distance

Core Design Contradiction:

Illumination intensityVSLength of stationary object

Solution Approach 1:

The invention applies reflective materials specifically to the internal surfaces of the housing where they are most effective - the sides and bottom surfaces that directly interact with light from the sources. This localized application of reflectivity maximizes light distribution without requiring the entire device to maintain large dimensions.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The invention changes the optical parameters of the housing surfaces by applying reflective materials, transforming ordinary surfaces into light-distributing surfaces. This parameter change (adding reflectivity) enables effective illumination in compact spaces without requiring minimum distances.

Inventive Principle:

Principle #35Parameter changes

3Illumination intensity

If solid blocks of light-diffusive material are used, then light distribution is achieved, but manufacturing complexity increases for small-sized signs

Engineering Contradiction:

Improvelight distributionVSAvoidmanufacturing process

Core Design Contradiction:

Illumination intensityVSEase of manufacture

Solution Approach 1:

The invention segments the light distribution function into separate components: light sources positioned at specific locations, reflective surfaces on housing interiors, and open front surfaces. This segmentation allows each component to be manufactured independently using standard processes, avoiding the need for complex monolithic light-diffusive blocks.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The housing structure serves multiple functions simultaneously: it provides mechanical support, defines the sign shape, distributes light through its geometry, and incorporates reflective surfaces. This multi-functionality eliminates the need for separate light-diffusive materials and simplifies manufacturing.

Inventive Principle:

Principle #6Universality (Multi-functionality)

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 uniform backlighting, reduces lighting peaks, and allows for economical and rapid manufacturing of luminous signs with IP protection, suitable for various shapes and sizes, ensuring consistent illumination without the need for precise component alignment.

Implementation Method 1

a light-reflective substrate with at least one electrically powered light radiation source thereon, a light-reflective cover layer arranged facing the planar substrate

Methodology Applied

Scientific EffectLight reflection: Reflection

Implementation Method 2

a light-permeable support structure arranged between the planar substrate and the cover layer

Methodology Applied

Scientific EffectLight transmission:

Data Source

PatentEP3404317B1A lighting device and corresponding method

Publication Date: 2020.01.01 OSRAM SOC RIUNITE OSRAM EDISON CLERICI

Figure 1~4
Figure 5~6
Figure 7~8

AI summary

A lighting device (10), e.g. for signage applications, includes: - a light-reflective (12a) planar substrate (12) with one or more light radiation sources (14), e.g. LED sources, thereon, - a light-reflective cover layer (18) arranged facing the planar substrate (12), - a light-permeable support structure (16) arranged between the planar substrate (12) and the cover layer (18). The support structure (16) includes opposite end walls (16a) extending between the planar substrate (12) and the cover layer (16), said end walls (16a) providing light emission surfaces of light from at least one light radiation source (14).