Light Guide Plate Grooves for Local Dimming

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current light units for display applications face challenges in achieving optical uniformity and efficient power management, particularly in providing varying luminance across different areas of a display panel, which affects image quality and power consumption.

Innovation Solution

A light unit comprising a light guide plate with grooves on its bottom surface and a light guide extension, integrated with LEDs and a reflective member, allows for individual control of light emission areas, enhancing optical uniformity and enabling partial driving methods like local dimming and impulsive driving to reduce power consumption and improve contrast.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If a light guide plate with grooves and light guide extension is used to enable individual control of light emission areas, then optical uniformity and image quality are improved, but device complexity increases

Engineering Contradiction:
Improveoptical uniformityVSAvoiddevice complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The light guide plate is divided into multiple grooves that segment the light emission areas, allowing individual control of different regions. This segmentation enables precise control of light quantity distribution across sub-areas, achieving optical uniformity and local dimming functionality while managing device complexity through systematic division.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The light guide extension is positioned at specific locations corresponding to the grooves to provide localized light emission control. This local quality approach allows different parts of the display to have different luminance characteristics, enabling image quality improvement and power consumption reduction in specific areas without affecting the entire system.

Inventive Principle:
Principle #3Local quality

2Use of energy by moving object

If light guide extension is added to enable partial driving methods, then power consumption is reduced, but device complexity increases

Engineering Contradiction:
Improvepower consumptionVSAvoiddevice complexity
Core Design Contradiction:
Use of energy by moving objectVSDevice complexity

Solution Approach 1:

The light guide plate is segmented into multiple grooves that correspond to different display areas, enabling independent control of light emission in each segment. This segmentation allows partial driving methods where only specific grooves are activated based on display content, significantly reducing power consumption while maintaining manageable device complexity through modular architecture.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The light guide extension enables periodic or impulsive driving methods where light emission is activated only when and where needed. By controlling the light guide extension to emit light periodically or impulsively based on display requirements, power consumption is reduced while the systematic design keeps device complexity controlled.

Inventive Principle:
Principle #19Periodic action

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 achieves improved optical uniformity, reduced power consumption, and enhanced image quality by allowing precise control of light quantity distribution across sub-areas, enabling the display apparatus to show images of higher quality.

Implementation Method 1

a light guide plate (120) having a top surface functioning as a surface light source

Methodology Applied
Scientific EffectLight guide: Waveguide (optics)

Implementation Method 2

at least one reflective member (140) arranged under or on the bottom surface of the light guide plate (120)

Methodology Applied
Scientific EffectReflection: Reflection

Data Source

PatentEP2806208B1Light unit with light guide plate
Publication Date: 2019.09.04 LG INNOTEK CO LTD
  • EP2806208B1 patent drawingFigure 1
  • EP2806208B1 patent drawingFigure 2~3
  • EP2806208B1 patent drawingFigure 4~5

AI summary

The light unit comprises a light guide plate (120) comprising a plurality of areas; at least one groove (122) formed on one side of the light guide plate (120); a module substrate (110) arranged under the groove (122); and at least one light emitting diode (115) disposed on the module substrate (110). The module substrate (110) is configured to supply electric power to the at least one light emitting diode (115) such that the areas of the light guide plate (120) emit light having different luminance from one area to another.