Aerial Image Mirror Layout to Reduce Ghost Images
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing aerial image display devices suffer from image light being directed in unintended directions, leading to ghost images and reduced viewability due to the use of optical elements like beam splitters and retroreflective plates.
Innovation Solution
Incorporating a reflective optical system with concave mirrors and a light shield to redirect image light effectively, reducing the likelihood of unintended reflections and ghost images by blocking direct paths with a light shield positioned off the optical path.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If beam splitters and retroreflective plates are used to direct image light, then the aerial image can be formed, but ghost images occur and viewability is reduced
Solution Approach 1:
The patent removes beam splitters and retroreflective plates from the optical system, replacing them with a reflective optical system using only mirrors. This extraction of problematic optical elements eliminates the source of ghost images while maintaining the aerial image formation function through the mirror arrangement (first concave mirror, second concave mirror, and optionally convex mirror).
Solution Approach 2:
The patent introduces a light shield as an intermediary element positioned between the display and the second concave mirror. This light shield blocks direct light paths that would otherwise create ghost images, acting as a mediator to prevent harmful light from reaching the observer while allowing the desired aerial image light to pass through its designated optical path.
2Reliability
If multiple optical elements are used to redirect image light, then the aerial image can be formed, but device complexity increases
Solution Approach 1:
The patent replaces complex optical elements (beam splitters, retroreflective plates) with a simpler reflective optical system using only mirrors. This substitution maintains the aerial image formation capability while reducing optical complexity, as mirrors provide straightforward light redirection without the layered structures and multiple surfaces of beam splitters and retroreflective plates.
Solution Approach 2:
The optical system is segmented into distinct functional components: a first concave mirror for initial light redirection, a second concave mirror for aerial image formation, and optionally a convex mirror for additional light path control. This segmentation allows each mirror to perform its specific function efficiently, simplifying the overall system design and making it easier to optimize each component independently.
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 enhances viewability by minimizing ghost images and maintaining luminance, while reducing power consumption and device size through optimized mirror arrangements and the use of a light shield.
Implementation Method 1
The first concave mirror reflects, in a direction different from a direction toward the display, image light emitted from the display surface
Implementation Method 2
The second concave mirror reflects, in a direction different from a direction toward the first concave mirror, the image light reflected from the first concave mirror and forms an aerial image as a real image from the image light
Implementation Method 3
The light shield is between the display and the second concave mirror. The light shield is located off an optical path of the image light extending from the display surface to the aerial image through the first concave mirror and the second concave mirror
Implementation Method 4
The convex mirror reflects, in a direction different from a direction toward the first concave mirror, the image light reflected from the first concave mirror
Implementation Method 5
The focusing member is between the display and the first concave mirror. The focusing member collimates the image light emitted from the display surface
Data Source
AI summary
An aerial image display device includes a display, a first concave mirror, a second concave mirror, and a light shield. The display includes a display surface. The first concave mirror reflects, in a direction different from a direction toward the display, image light emitted from the display surface. The second concave mirror reflects, in a direction different from a direction toward the first concave mirror, the image light reflected from the first concave mirror and forms an aerial image as a real image from the image light. The light shield is between the display and the second concave mirror. The light shield is located off an optical path of the image light extending from the display surface to the aerial image through the first concave mirror and the second concave mirror.