HUD Polarizer Segmentation for Light Efficiency

Solution Overview

Problem

Conventional head-up display (HUD) devices suffer from reduced energy efficiency and visibility of internal structures due to the use of translucent resin dustproof sheets, which compromise the transmissivity and allow external recognition of internal components.

Innovation Solution

A HUD device design incorporating a first light polarizer, a liquid crystal layer with switchable display and non-display pixels, and a second light polarizer acting as both a dustproof sheet and energy-efficient light controller, intercepting unwanted light while allowing display pixels to pass through, thereby enhancing energy efficiency and concealing internal structures.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a translucent resin dustproof sheet is used, then the internal structure can be protected, but the energy efficiency of light source light decreases and internal structures become visible from the exterior

Engineering Contradiction:

Improvedustproof protectionVSAvoidlight energy transmission efficiency

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The dustproof sheet is segmented into multiple functional layers: a base translucent resin layer for dust protection, and a superimposed polarizing plate layer for light control. This segmentation allows each layer to perform its specific function independently, resolving the contradiction between protection and energy efficiency.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The invention uses a composite structure combining translucent resin material and polarizing plate material in a single integrated dustproof sheet. This composite material approach enables simultaneous achievement of dustproof protection and light energy efficiency by leveraging the complementary properties of each material.

Inventive Principle:

Principle #40Composite materials

2Reliability

If a translucent resin dustproof sheet is used, then the internal structure can be protected, but internal structures become visible from the exterior

Engineering Contradiction:

Improvedustproof protectionVSAvoidvisibility of internal structures

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The dustproof sheet is segmented into multiple functional layers: a base translucent resin layer for dust protection, and a superimposed polarizing plate layer for light control. This segmentation allows each layer to perform its specific function independently, resolving the contradiction between protection and energy efficiency.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The invention uses a composite structure combining translucent resin material and polarizing plate material in a single integrated dustproof sheet. This composite material approach enables simultaneous achievement of dustproof protection and light energy efficiency by leveraging the complementary properties of each material.

Inventive Principle:

Principle #40Composite materials

3Object-affected harmful factors

If the dustproof sheet is colored in dark color or a half mirror is used to prevent internal structure visibility, then internal structures are concealed, but the transmissivity of display light further decreases and energy efficiency worsens

Engineering Contradiction:

Improvevisibility of internal structuresVSAvoidlight energy transmission efficiency

Core Design Contradiction:

Object-affected harmful factorsVSLoss of energy

Solution Approach 1:

Instead of changing the color or reflectivity parameters of the dustproof sheet, the invention changes the polarization state parameter of light. The polarizing plate controls light transmission based on polarization direction rather than absorption or reflection, allowing high transmissivity while preventing internal structure visibility through polarization filtering.

Inventive Principle:

Principle #35Parameter changes

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 significantly improves energy efficiency and prevents external visibility of internal structures by optimizing light transmission and polarization, while allowing for easy manufacturing using existing materials.

Implementation Method 1

a first light polarizer takes out a linearly polarized light from light source light emitted from a light source

Methodology Applied

Scientific EffectPolarization: Polarisation

Implementation Method 2

the polarization direction of the display pixel and the polarization direction of the non-displaying pixel are different from each other

Methodology Applied

Scientific EffectLiquid crystal polarization switching: Liquid Crystals

Implementation Method 3

a second light polarizer intercepts a light of an interception axis intersecting a transmission axis while a light of the transmission axis is made to pass through

Methodology Applied

Scientific EffectPolarization filtering: Polarisation

Data Source

PatentUS10036890B2Head-up display device

Publication Date: 2018.07.31 DENSO CORP

AI summary

A head-up display device includes: a light source that emits light source light; a first light polarizer that takes out a linearly polarized light from the light source light; a liquid crystal layer, in which a display pixel that displays a picture and a non-displaying pixel which does not display a picture are able to be switched from each other, a polarization direction of the display pixel and a polarization direction of the non-displaying pixel being different from each other; and a second light polarizer. A part of the light source light corresponding to the display pixel passes through the second light polarizer by prohibiting a light of an interception axis intersecting a transmission axis while a light of the transmission axis is made to pass through.