Display Device Light Guide Retroreflection Stray Light Control
Solution Overview
Problem
Display devices that form images in the air face deterioration in display quality due to stray light deviating from the optical path, which affects image clarity and contrast.
Innovation Solution
The use of a display device configuration that includes a display module, an optical element with a polarizing filter and retardation film, and a reflective element with a retroreflective surface, along with light-guides that impart directivity to the display light, helps to restrict emission angles and prevent stray light from interfering with the image formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If a reflective element with retroreflective surface is added to improve light utilization efficiency, then display quality deteriorates due to stray light deviation
Solution Approach 1:
A light guide is introduced as an intermediary component between the display module and the reflective element. The light guide directs display light toward the optical element while preventing stray light from reaching the reflective element, thus resolving the contradiction between improving light utilization and preventing stray light interference.
Solution Approach 2:
The optical system is segmented into distinct functional zones: a display module for light emission, a light guide for directional control, an optical element for image formation, and a reflective element for retroreflection. This segmentation allows each component to perform its function without interfering with others, particularly preventing stray light from the display module from reaching the reflective element.
2Manufacturing precision
If light guides are used to restrict emission angles and improve image clarity, then device complexity increases
Solution Approach 1:
The light guide serves multiple functions simultaneously: it directs display light toward the optical element at appropriate angles, prevents stray light from reaching the reflective element, and contributes to overall image quality enhancement. This multi-functionality reduces the need for additional separate components, thereby limiting the increase in device complexity.
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
This configuration enhances the efficiency of display light usage, improves image clarity, and suppresses glare and blurring caused by external light, resulting in improved display quality by ensuring that display light is directed correctly and stray light is minimized.
Implementation Method 1
a retroreflective surface that retroreflects the display light in an opposite direction to the display light
Implementation Method 2
an optical element including a polarizing filter and a retardation film
Data Source
AI summary
According to one embodiment, a display device includes a display module which emits display light, an optical element which transmits or reflects the display light, a reflective element which retroreflects the display light reflected from the optical element, and a first light-guide which imparts directivity toward the optical element to the display light emitted from the display module.