Vehicle Headlight Dove Prism Rotation Mechanism

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Vehicle headlight devices struggle to provide adequate illumination to the corner area when a vehicle tilts during turns, leading to inadequate lighting and potential glare towards oncoming vehicles due to the tilting of the headlight beam.

Innovation Solution

A vehicle headlight device with a Dove prism or rotation mirror that rotates relative to the light source, adjusting the light distribution pattern to maintain effective illumination of the corner area by rotating the optical element based on the vehicle's bank angle, reducing the load on the motor and minimizing the size of the rotating components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If the light emitting body and lens are rotated to compensate for vehicle tilt, then the corner area illumination is improved, but the motor load increases due to the large size of the lens

Engineering Contradiction:
Improvecorner area illuminationVSAvoidmotor load
Core Design Contradiction:
Illumination intensityVSForce

Solution Approach 1:

The optical system is divided into two independent parts: a fixed large lens that remains stationary, and a movable light emitting body that rotates independently. This segmentation allows the large lens to provide sufficient illumination spread without requiring rotation, while only the smaller light emitting body needs to be rotated by the motor to compensate for vehicle tilt, significantly reducing motor load.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Instead of rotating the lens to adjust light distribution as in conventional systems, this invention inverts the approach by rotating the light emitting body while keeping the lens fixed. This inversion of the rotation target from the large lens to the smaller light emitting body achieves the same compensation effect with much lower mechanical load on the driving motor.

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

2Illumination intensity

If a large lens is rotated to maintain light distribution, then illumination coverage is maintained, but the device size and complexity increase

Engineering Contradiction:
Improveillumination coverageVSAvoiddevice size
Core Design Contradiction:
Illumination intensityVSDevice complexity

Solution Approach 1:

The optical system is divided into two independent parts: a fixed large lens that remains stationary, and a movable light emitting body that rotates independently. This segmentation allows the large lens to provide sufficient illumination spread without requiring rotation, while only the smaller light emitting body needs to be rotated by the motor to compensate for vehicle tilt, significantly reducing motor load.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The rotation function is extracted from the lens and transferred to the light emitting body. By taking out the rotational mechanism from the large lens assembly and applying it only to the compact light emitting body, the invention eliminates the complexity of rotating large components while preserving the illumination coverage function.

Inventive Principle:
Principle #2Taking out (Extraction)

3Device complexity

If the headlight device tilts with the vehicle body, then the structure is simple, but the corner area becomes dark and oncoming vehicles experience glare

Engineering Contradiction:
Improvestructural simplicityVSAvoidcorner area illumination
Core Design Contradiction:
Device complexityVSIllumination intensity

Solution Approach 1:

The invention introduces dynamic adjustment capability to the light emitting body, allowing it to rotate independently in response to vehicle tilt conditions. This dynamic adjustment compensates for the fixed lens position, maintaining proper light distribution to the corner area without requiring the entire headlight assembly to tilt mechanically, thus preserving structural simplicity while improving illumination performance.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system incorporates a tilt angle sensor that detects vehicle bank angle and provides feedback to a control unit. The control unit processes this information and actuates the motor to rotate the light emitting body by a corresponding angle, creating a closed-loop feedback system that automatically compensates for vehicle tilt to maintain optimal illumination patterns.

Inventive Principle:
Principle #23Feedback

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 ensures consistent illumination of the corner area and reduces glare towards oncoming vehicles by adjusting the light distribution pattern in response to the vehicle's tilt, while also reducing the motor load and device size.

Implementation Method 1

an optical element for receiving the light at an incidence surface, changing the propagation direction of the light to bring the light to a reflecting surface, reflecting the light at the reflecting surface, and changing the propagation direction of the reflected light at the exit surface

Methodology Applied
Scientific EffectRefraction: Refraction

Implementation Method 2

an optical element for receiving the light at an incidence surface, changing the propagation direction of the light to bring the light to a reflecting surface, reflecting the light at the reflecting surface, and changing the propagation direction of the reflected light at the exit surface

Methodology Applied
Scientific EffectReflection: Reflection

Data Source

PatentEP2894086B1Vehicle headlight device
Publication Date: 2017.12.20 MITSUBISHI ELECTRIC CORP
  • EP2894086B1 patent drawingFigure 1(A)~1(B)
  • EP2894086B1 patent drawingFigure 2
  • EP2894086B1 patent drawingFigure 3

AI summary

A vehicle headlight device 100 includes a light source 11, a Dove prism 40, and a rotation mechanism 50. The light source 11 emits light. The Dove prism 40 changes a propagation direction of light received at an incidence surface 401 to bring the light to a reflecting surface 402, and changes a propagation direction of light reflected at the reflecting surface 402 to output the light from an exit surface 403. The rotation mechanism 50 rotatably supports the Dove prism 40 about a line which passes through the incidence surface 401 and the exit surface 403 as an axis of rotation R, and rotates the Dove prism 40 in a direction opposite to a bank direction of a vehicle body in accordance with a bank angle k of the vehicle body.