Vehicle Display Directional Mirror Adjustment Mechanism

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing vehicle display devices face challenges in adjusting the focal position of virtual images and protecting the projecting unit from external light, requiring significant space for mirror movement and potentially causing heat-related deterioration in the light source and LCD.

Innovation Solution

A vehicle display device with a directional mirror that uses a tilting fulcrum part and a biasing member to adjust the focal position within a narrow space, and a retracting operation that moves the mirror forward to prevent external light from affecting the projecting unit, utilizing a single actuator for both operations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the mirror is rotated around a fulcrum at the center of the holding member to adjust the virtual image position, then the driver can view the virtual image within the field of view, but the device requires expanded backward space which impairs downsizing

Engineering Contradiction:
Improvevirtual image position adjustmentVSAvoiddevice space requirement
Core Design Contradiction:
Ease of operationVSVolume of moving object

Solution Approach 1:

The patent changes the rotation axis from a horizontal fulcrum at the center to a vertical fulcrum at the upper end of the holding member. This dimensional change in the rotation axis allows the mirror to rotate in a different plane, enabling virtual image position adjustment without requiring backward space expansion, thus resolving the space constraint while maintaining adjustability

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

2Object-affected harmful factors

If the mirror is rotated with the upper end acting as a fulcrum to protect from external light, then the projecting unit is protected, but the backward depth dimension of the case needs to be elongated

Engineering Contradiction:
Improveexternal light protectionVSAvoidcase backward depth
Core Design Contradiction:
Object-affected harmful factorsVSLength of stationary object

Solution Approach 1:

Instead of rotating the mirror to direct external light away from the projecting unit (which requires backward space), the patent inverts the approach by positioning the fulcrum at the upper end and rotating the mirror forward. This causes the lower end to move forward toward the projecting unit, using the mirror's rotation to shield the projecting unit from external light while actually reducing the required backward depth of the case

Inventive Principle:
Principle #13The other way round (Inversion)

3Measurement precision

If the lower end of the mirror is largely moved in the backward direction to adjust the virtual image position, then the virtual image can be positioned within the driver's field of view, but the internal space of the housing needs to be expanded backward

Engineering Contradiction:
Improvevirtual image position precisionVSAvoidhousing internal space
Core Design Contradiction:
Measurement precisionVSVolume of moving object

Solution Approach 1:

The patent changes the rotation dimension by positioning the fulcrum at the upper end rather than at the center. This allows the mirror to rotate in a vertical plane rather than requiring horizontal backward movement, achieving precise virtual image positioning without expanding the housing's backward internal space

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

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

Enables precise adjustment of virtual image position without expanding the device's space requirements and protects the projecting unit from external light, ensuring efficient operation and longevity of components.

Implementation Method 1

a directional mirror configured to reflect the projection light and to direct reflected light of the projection light upward at an oblique angle toward a transparent screen

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 2

a biasing member configured to give the directional mirror a biasing force with which the tilting fulcrum part is pressed against the fulcrum support

Methodology Applied
Scientific EffectElastic force: Elasticity

Data Source

PatentEP3521885B1Vehicle display device
Publication Date: 2022.11.02 ALPINE ELECTRONICS INC
  • EP3521885B1 patent drawingFigure 1
  • EP3521885B1 patent drawingFigure 2
  • EP3521885B1 patent drawingFigure 3

AI summary

In a vehicle display device, projection light output from a projecting unit is reflected on an intermediate mirror and is further reflected on a directional mirror. The reflected light is given to a windshield glass as directed reflected light. In an adjustment operation, the directional mirror is rotated around the tilting fulcrum parts by a driving unit to adjust the height of a virtual image formed in front of the windshield glass. In a retracting operation, the lower end of the directional mirror is largely moved forward by the driving unit, rotating the directional mirror with an abutting point between the directional mirror and the upper support acting as a fulcrum. This prevents external light (sunlight) from adversely affecting the projecting unit.