Light-Emitting Module Cover Structure for Stray Light Reduction

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Light-emitting modules suffer from stray light on the irradiation surface, which affects the clarity and aesthetic appearance, and the cover member is prone to damage.

Innovation Solution

A light-emitting module design featuring a cover member with a first region of lower diffusivity and a second region of higher diffusivity, covered by a harder light-transmissive member, reduces stray light and protects the cover member from damage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If the cover member is made with a single uniform structure, then the manufacturing process is simple, but the stray light control is insufficient and the surface is prone to damage

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidstray light and surface damage

Core Design Contradiction:

Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The cover member is designed with different regions having different light diffusivity properties. The first region has lower light diffusivity while the second region has higher light diffusivity, allowing each region to perform its specific function (central light transmission vs. stray light diffusion) while collectively solving the stray light problem without compromising manufacturing feasibility

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The cover member is constructed as a composite structure combining regions with different optical properties. This composite design integrates materials or structural configurations that provide both low and high light diffusivity in different areas, achieving superior stray light control while maintaining durability and manufacturability

Inventive Principle:

Principle #40Composite materials

2Device complexity

If the upper surface of the cover member is exposed, then the structure is simple, but the cover member is prone to damage and has poor chemical resistance

Engineering Contradiction:

Improvestructural complexityVSAvoiddurability and chemical resistance

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

A light-transmissive member with higher hardness than the cover member is positioned to cover the upper surface of the cover member. This thin film-like protective layer provides enhanced mechanical strength and chemical resistance while maintaining light transmission, protecting the softer cover member material without significantly increasing structural complexity

Inventive Principle:

Principle #30Flexible shells and thin 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

The design effectively minimizes stray light and enhances the aesthetic appearance while providing improved chemical resistance and durability to the cover member.

Implementation Method 1

a second region provided around the first region and having a higher light diffusivity than a light diffusivity of the first region

Methodology Applied

Scientific EffectLight diffusion: Scattering

Implementation Method 2

a lens disposed over the light source and configured to transmit light from the light source

Methodology Applied

Scientific EffectLight transmission: Refraction

Data Source

PatentUS20250354674A1Light-emitting module with cover member and light-transmissive member having higher hardness than cover member

Publication Date: 2025.11.20 NICHIA CORP

AI summary

A cover structure includes: a lens; and a cover member disposed over the lens and having a lower surface and an upper surface. The lower surface of the cover member includes: a first region, and a second region located around the first region. A light diffusing substance is disposed on the lower surface of the cover member in the second region, such that a light diffusivity of the second region is higher than a light diffusivity of the first region. The upper surface of the cover member is covered by a light-transmissive member, and a hardness of the light-transmissive member is higher than a hardness of the cover member.