Display Element ZnS Phosphor Codoping for Stable Brightness
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional ZnS-based phosphor materials in display elements suffer from gradual brightness loss over time, necessitating improvements in aging stability and brightness.
Innovation Solution
Incorporating group 4 element codoping in a phosphor layer of activator-doped zinc sulfide (ZnS:X,Y) with an average atomic percentage of group 4 elements ( at − % Y ave ) of at least 0.01 atomic percent, enhancing the aging stability and/or brightness of the display element.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional ZnS-based phosphor materials are used, then high aging stability is achieved, but gradual brightness loss occurs over time
Solution Approach 1:
The patent changes the compositional parameters of the ZnS phosphor material by introducing group 4 element codoping (Ti, Zr, or Hf) at specific concentration ranges (0.01-5 at%). This compositional modification alters the electronic structure and defect properties of the material, simultaneously improving both aging stability and brightness characteristics without the trade-off present in conventional materials.
Solution Approach 2:
The invention creates a composite phosphor material system by combining ZnS host material with group 4 element dopants (Ti, Zr, Hf) and activator elements. This composite approach leverages the beneficial properties of each component: ZnS provides the base phosphor structure, group 4 elements enhance stability and brightness, and activators provide luminescence centers, achieving superior overall performance.
2Illumination intensity
If dopants are added to ZnS host material to create luminescence centers, then brightness is improved, but aging stability may be compromised
Solution Approach 1:
The patent optimizes the doping parameters by specifying precise concentration ranges for both activators (0.1-5 at%) and group 4 element codopants (0.01-5 at%). This parameter optimization ensures that the luminescence centers are sufficiently dense for high brightness while the group 4 elements provide structural stabilization to maintain aging stability, resolving the contradiction between brightness enhancement and stability preservation.
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 codoping significantly increases the aging stability and brightness of the display element, with improved luminance values maintained over time compared to conventional materials.
Implementation Method 1
Phosphor materials that exhibit luminescence are commonly used in display elements, such as inorganic thin film electroluminescent (TFEL) display elements
Data Source
Figure 1
Figure 2
AI summary
This disclosure relates to use of group 4 element codoping in a phosphor layer of activator-doped zinc sulfide of a display element, a display element, and a method for manufacturing a display element. The display element (100) comprises a first insulator layer (111), a second insulator layer (112), and a first phosphor layer (121) of activator-group 4 element codoped zinc sulfide between the first insulator layer (111) and the second insulator layer (112). The first phosphor layer (121) has an average atomic percentage of group 4 elements of at least 0.01 atomic percent.