Directional Pixel Backlight for Glassless 3D Displays
Solution Overview
Problem
Current glassless 3D display technologies face challenges in effectively directing rays to subpixels without mixing colors or reducing brightness, particularly when using diffraction gratings as optical controllers, leading to issues with cross-talk and image quality.
Innovation Solution
A display device with a backlight that generates directional rays using a diffraction grating, where a white light source is concentrated and scattered by a directional pixel, allowing each directional ray to be precisely incident on corresponding subpixels, optimizing the size and arrangement of directional pixels to enhance light efficiency and reduce cross-talk.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a diffraction grating is used as an optical controller to direct rays to subpixels, then the 3D image can be expressed without glasses, but color mixing and cross-talk occur between adjacent subpixels
Solution Approach 1:
The patent applies local quality by making each directional pixel have a specific shape (triangular, rectangular, or circular) that corresponds to its position in the array, with each pixel configured to direct light in a specific direction toward corresponding subpixels. This localized directional control prevents color mixing and cross-talk between adjacent subpixels while maintaining glassless 3D display capability
Solution Approach 2:
The patent segments the backlight into multiple directional pixels arranged in an array, where each directional pixel independently controls light direction toward specific subpixels. This segmentation allows precise directional control of light for each subpixel, preventing cross-talk while enabling glassless 3D display
2Object-affected harmful factors
If the size of directional pixels is reduced to match subpixel dimensions, then cross-talk is minimized, but light efficiency and brightness are reduced
Solution Approach 1:
The patent changes the parameter of directional pixel size to be equal to or larger than subpixel size, which is counterintuitive but resolves the contradiction. By making directional pixels larger and using directional control through specific shapes and arrangements, the patent achieves both reduced cross-talk and improved light efficiency, as larger pixels collect more light while directional control ensures precise light delivery to corresponding subpixels
3Loss of energy
If directional pixels are arranged to cover the entire backlight area, then light efficiency is improved, but manufacturing precision and alignment become more difficult
Solution Approach 1:
The patent uses color filters in the display panel that correspond to different directions of light from directional pixels. Each directional pixel directs light toward subpixels with matching color filters, enabling automatic alignment through color correspondence rather than relying solely on precise mechanical positioning. This reduces manufacturing complexity while maintaining high light efficiency
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 improves the brightness and image quality of the 3D display by ensuring directional rays are accurately directed to subpixels, minimizing color mixing and cross-talk, while allowing for flexible arrangement of directional pixels to suit multiview or light-field methods.
Implementation Method 1
a diffraction grating has been used as the optical controller. The diffraction grating may change a path of light to be output by adjusting an incidence angle of light to be incident on the diffraction grating
Implementation Method 2
a white light source is concentrated and scattered by a directional pixel, allowing each directional ray to be precisely incident on corresponding subpixels
Data Source
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AI summary
A method of generating directional rays and apparatuses performing the method are disclosed. A backlight may include a light source configured to generate a ray, a light guide plate configured to transfer the ray to a display panel, and a directional pixel configured to generate a plurality of directional rays by scattering the ray, in which each of the directional rays may be incident at a corresponding subpixel in the display panel.