Stereoscopic Glasses With Tilted Filters To Reduce Flare

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional stereoscopic imaging systems face challenges with illumination efficiency, high operational and equipment costs, and image quality issues due to inefficient light utilization and sensitivity to angular shifts and head motion in filter glasses, particularly in spectral separation methods, and the complexity of maintaining high polarization control in polarized light projection systems.

Innovation Solution

The use of filter glasses with tilted filter elements to reduce flare light reflection, combined with tunable light sources and hybrid filter designs that incorporate dichroic and absorptive layers to enhance spectral separation and minimize crosstalk, thereby improving image contrast and brightness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If spectral separation filters are used to distinguish left- and right-eye images, then color space separation is achieved, but image quality is reduced by angular shift, head motion, and tilt

Engineering Contradiction:
Improvespectral separation capabilityVSAvoidimage quality
Core Design Contradiction:
Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The patent applies curved filters instead of flat filters to compensate for angular shifts. The curvature is specifically designed to counteract the wavelength shifts that occur when light enters the filter at oblique angles, thereby maintaining spectral separation performance across different viewing angles and head positions

Inventive Principle:
Principle #14Spheroidality (Curvature)

Solution Approach 2:

The patent changes the geometric parameter of the filter from flat to curved, which fundamentally alters how light interacts with the filter surface. This parameter change enables the filter to maintain its spectral separation characteristics across a wider range of incident angles, directly addressing the angular sensitivity problem

Inventive Principle:
Principle #35Parameter changes

2Adaptability or versatility

If filters are used to block portions of primary colors for spectral separation, then left- and right-eye images are distinguished, but significant light loss occurs due to filtering

Engineering Contradiction:
Improvespectral separation capabilityVSAvoidlight loss
Core Design Contradiction:
Adaptability or versatilityVSLoss of energy

Solution Approach 1:

The patent uses curved filters with locally varied optical properties. Different regions of the curved filter are optimized for different incident angles, allowing the filter to maintain high transmission efficiency for on-axis light while still providing effective spectral separation for off-axis light. This local optimization reduces overall light loss compared to flat filters

Inventive Principle:
Principle #3Local quality

3Adaptability or versatility

If conventional flat filters are used in filter glasses, then spectral separation is achieved, but flare light reflection causes visual noise and reduced image contrast

Engineering Contradiction:
Improvespectral separation capabilityVSAvoidflare light reflection
Core Design Contradiction:
Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The curved filter surface changes the angle of incidence for reflected light, directing flare light away from the viewer's line of sight. This geometric modification effectively reduces the visibility of flare reflections while maintaining the filter's spectral separation function

Inventive Principle:
Principle #14Spheroidality (Curvature)

Solution Approach 2:

The patent converts the harmful flare light reflection into a beneficial effect by using the curved surface to redirect reflected light away from the viewer. What would normally be a source of visual noise becomes a mechanism for improving image contrast by eliminating unwanted reflections

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

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 approach reduces visual noise and improves image contrast by minimizing flare light reflection and increasing the efficiency of light utilization, while also reducing operational and equipment costs through more effective spectral separation and reduced complexity in optical design.

Implementation Method 1

reduce unwanted flare... reduce visual noise... amount of flare light reflected from the front surface of the filter glasses

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 2

hybrid filter designs that incorporate dichroic and absorptive layers to enhance spectral separation

Methodology Applied
Scientific EffectDichroic filtering: Dichroic Filter

Implementation Method 3

hybrid filter designs that incorporate dichroic and absorptive layers to enhance spectral separation

Methodology Applied
Scientific EffectAbsorption: Absorption (EM radiation)

Data Source

PatentEP2805519B1Stereoscopic glasses using tilted filters
Publication Date: 2022.12.21 IMAX THEATERS INT
  • EP2805519B1 patent drawingFigure 1
  • EP2805519B1 patent drawingFigure 2
  • EP2805519B1 patent drawingFigure 3A

AI summary

Filter glasses for use by an observer of a stereoscopic digital display system that displays stereoscopic images including first-eye images and second-eye images. The filter glasses include a first-eye filter that substantially transmits light from the first-eye images and blocks light from the second-eye images, and a second- eye filter that substantially transmits light from the second-eye images and blocks light from the second-eye images. A frame is used to position the first-eye filter in front of the observer's first eye and to position the second-eye filter in front of the observer's second eye, such that the front surfaces of the filters are oriented at a tilt angle of at least 5 degrees relative to vertical so that light from the display surface that is reflected from the first-eye filter and the second-eye filter is directed over the heads of other observers that are seated in front of the observer.