Interior Light With Offset LED And Light Guide Plate

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing interior lights struggle to effectively reduce the direct component of light emission while increasing the indirect component to minimize glare without reducing overall light output or requiring additional light sources, due to complex and costly design structures.

Innovation Solution

The interior light features a housing with a recess containing an LED linear module and a light guide plate, where the LED module is positioned at a distance from the light guide plate's side edge, allowing for controlled emission of light as both direct and indirect components through strategically placed openings, with a decoupling structure and reflector to optimize light distribution.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If the LED linear module is positioned close to the light guide plate for efficient light coupling, then the direct light component is increased, but the indirect light component is reduced and glare increases

Engineering Contradiction:
Improvedirect light componentVSAvoidglare
Core Design Contradiction:
Illumination intensityVSObject-affected harmful factors

Solution Approach 1:

The patent positions the LED linear module in a second plane that is offset from the first plane containing the light guide plate. This spatial separation in the vertical dimension allows light to be emitted at various angles, creating both direct and indirect components without requiring the LED to be immediately adjacent to the light guide plate edge.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent introduces a reflector as an intermediary element between the LED linear module and the light guide plate. The reflector captures light that would otherwise be lost and redirects it into the light guide plate, improving coupling efficiency without requiring close proximity that would increase glare.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Illumination intensity

If complex structures are added to the light guide plate edge to increase indirect light, then the indirect light component is improved, but the device complexity and manufacturing costs increase

Engineering Contradiction:
Improveindirect light componentVSAvoidcoupling structure complexity
Core Design Contradiction:
Illumination intensityVSDevice complexity

Solution Approach 1:

The patent extracts the light coupling function from the light guide plate edge itself and relocates it to a separate LED linear module positioned in a different plane. This separates the light generation function from the light guiding function, simplifying the overall structure while maintaining effective light coupling through the reflector.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The reflector serves multiple functions: it captures light from the LED linear module, redirects light into the light guide plate to enhance coupling, and contributes to creating the indirect light component. This multi-functionality reduces the need for additional specialized structures.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Object-affected harmful factors

If the LED linear module is spaced apart from the light guide plate, then the indirect light component is increased and glare is reduced, but the light coupling efficiency decreases

Engineering Contradiction:
Improveglare reductionVSAvoidlight coupling efficiency
Core Design Contradiction:
Object-affected harmful factorsVSLoss of energy

Solution Approach 1:

The patent employs a composite optical system combining the LED linear module, reflector, and light guide plate in a multi-plane configuration. This composite structure allows light to travel through multiple paths and interfaces, maintaining coupling efficiency despite the spatial separation between the LED module and light guide plate.

Inventive Principle:
Principle #40Composite materials

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 configuration allows for a significant increase in the indirect light component while maintaining overall light output, reducing glare, and enabling adjustable light profiles without the need for additional light sources, thus enhancing energy-efficient and glare-reduced interior illumination.

Implementation Method 1

the light from one or more LED linear modules, each consisting of a multitude of LEDs arranged in a row, is coupled into one or more edges of a plate-shaped light guide plate. It is then guided via total internal reflection at the interfaces of the light guide plate and emitted through the output coupling structure.

Methodology Applied
Scientific EffectTotal internal reflection: Total Internal Reflection

Implementation Method 2

This output coupling structure is often an imprinted, geometrically defined structure that intentionally interrupts the total internal reflection within the light guide plate. As a result, the light either exits the light guide plate directly at these structures, indirectly, or the angle of the totally reflected light is altered by the output coupling structure

Methodology Applied
Scientific EffectRefraction: Refraction

Data Source

PatentEP3591281B1Interior light
Publication Date: 2020.12.23 HERBERT WALDMANN GMBH & CO KG
  • EP3591281B1 patent drawingFigure 1
  • EP3591281B1 patent drawingFigure 2

AI summary

The invention relates to an interior light (1), in particular an office light, comprising a housing (10) with a recess (20) in which at least one LED linear module (40) and at least one light guide plate (30), having at least one side edge (31, 32) and two interfaces (33, 34), are arranged, wherein the LED linear module (40) is configured to emit light into the recess (20), wherein the recess (20) has a first light-transmitting opening (12) for indirect illumination on a top surface (11) and a second light-transmitting opening (14) for direct illumination on a bottom surface (13), wherein the light guide plate (30) is arranged between the first opening (12) and the second opening (14) in a first plane (5), and wherein the at least one LED linear module (40) is spaced apart from the at least one side edge (31, 32)32) of the light guide plate (30) and/or in a second plane (6) spaced apart from the first plane (5) and emits the light into the recess (20).