Display Backlight Collimation for Windshield Reflection Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing display backlights in vehicles suffer from reflections on windshields due to light emission at vertical angles greater than the reflection angle, leading to inefficiencies and wasted power consumption.
Innovation Solution
A backlight system utilizing a collimated lightguide and a direction changing element with triangular prisms to convert collimated light into vertically narrow light, minimizing reflections by statically directing light without blocking, thus optimizing power efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If blocking elements, shutters, or obstructions are used to prevent windshield reflections, then reflections are reduced, but light is wasted and power consumption increases
Solution Approach 1:
The patent replaces mechanical blocking elements (shutters, obstructions, louvers) with an optical solution using a directional backlight and potentially polarizing filters. This substitution eliminates the need to physically block light, instead using optical properties to control light direction and polarization, thereby preventing reflections without wasting light energy.
Solution Approach 2:
The patent changes the directional parameters of the backlight by using a directional light source or optical elements to restrict light emission to angles below the critical reflection angle. This parameter change (controlling emission angle) prevents reflections at the windshield while maintaining light efficiency, avoiding the energy waste associated with blocking elements.
2Object-affected harmful factors
If blocking elements are used to prevent reflections, then reflections are avoided, but device complexity and cost increase
Solution Approach 1:
The patent replaces complex mechanical blocking infrastructure with a simpler optical approach using directional backlights and polarizing filters. This reduces device complexity by eliminating moving parts (shutters, louvers) and their control mechanisms, while still achieving the goal of preventing windshield reflections.
3Object-affected harmful factors
If displays are positioned below the windshield, then reflections occur, but display positioning is constrained
Solution Approach 1:
The patent changes the optical parameters (emission angle, polarization) of the display backlight rather than constraining display positioning. This allows displays to be positioned in various locations (including below the windshield) while using optical control to prevent reflections, thereby maintaining positioning flexibility.
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 system effectively prevents windshield reflections while maximizing power efficiency by minimizing wasted light and reducing the need for additional blocking elements, allowing displays to be positioned without obstructions.
Implementation Method 1
a collimated lightguide configured for collimating the edge light to a collimated light
Implementation Method 2
The receiving face may be configured for refracting the collimated light prior to the collimated light reaching the reflecting face
Implementation Method 3
a reflecting face configured for reflecting the collimated light received from the receiving face
Data Source
AI summary
A system for backlighting a display to avoid producing a reflection. The system may include a light source configured for generating a light, a collimated lightguide configured for collimating the light to a collimated light, and a direction changing element configured for directing the collimated light to a vertically narrow light operable to avoid producing reflections.