Mirror Angle Control for HUD Virtual Image Alignment

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Solution Overview

Problem

Existing display technologies struggle to overlay virtual images on actual images without misalignment from the user's viewpoint, particularly in head-up displays and augmented reality systems.

Innovation Solution

A display control device that adjusts the mirror angle in response to user input, using a correspondence relationship between the mirror angle and depth information to align the virtual image position with the external scene, ensuring accurate overlay without misalignment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a head-up display or augmented reality system is used to emphasize objects ahead, then the user's attention is directed to important information, but the virtual image becomes misaligned with the actual image from the user's viewpoint

Engineering Contradiction:
Improveease of providing directional informationVSAvoidalignment precision
Core Design Contradiction:
Ease of manufactureVSMeasurement precision

Solution Approach 1:

The system uses the imaging unit to capture the actual position of the windshield and the displayed position of the virtual image, then feeds this information back to the processor. The processor calculates the deviation between virtual and actual positions and adjusts the mirror angle accordingly, creating a closed-loop feedback system that maintains alignment

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent replaces manual mechanical adjustment of the mirror with an automated optical-electrical system. The imaging unit captures images, the processor calculates positions and deviations, and the mirror angle is automatically adjusted based on these calculations, substituting mechanical manual alignment with an automated optical measurement and electrical control system

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Device complexity

If the mirror angle is fixed to simplify the system, then the device complexity is reduced, but the display position cannot be adjusted to maintain alignment with the external scene

Engineering Contradiction:
Improvesystem complexityVSAvoidadaptability to user position
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The system transforms the static mirror angle into a dynamic parameter that can be automatically adjusted. The mirror angle changes in response to detected deviations between virtual and actual image positions, allowing the system to adapt to different viewing conditions while maintaining alignment

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system performs self-alignment by using its own imaging unit to detect misalignment, calculate the required adjustment, and automatically adjust the mirror angle without external intervention. The device serves itself to maintain proper alignment between virtual and real images

Inventive Principle:
Principle #25Self-service

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 virtual images to be accurately overlaid on actual images, improving user experience and safety by maintaining alignment regardless of user position or eye height variations.

Implementation Method 1

an angle of a mirror configured to reflect light for display on a display

Methodology Applied
Scientific EffectReflection: Reflection

Data Source

PatentEP4095585B1Display control device, display device, vehicle, display control method, and recording medium recorded with display control program
Publication Date: 2025.08.27 TOYOTA JIDOSHA KK
  • EP4095585B1 patent drawingFigure 1
  • EP4095585B1 patent drawingFigure 2
  • EP4095585B1 patent drawingFigure 3

AI summary

A display control device that includes: a processor; and a memory that is coupled with the processor and is configured to store a correspondence relationship between an angle of a mirror configured to reflect light for display on a display and depth information indicating a virtual display position of an image for display on the display so as to correspond to an external scene, the processor being configured to: receive input from a user, and change the mirror angle in response to the received input, adjust a display position of an image to be displayed on the display based on the depth information associated with the mirror angle after it is changed, and display the image on the display.