Silicate Luminescent Material for Field Emission Displays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current fluorescent materials used in field emission displays, such as sulfide and oxysulfide series, are prone to decomposition under electron beam bombardment, leading to reduced luminous efficiency and shorter device life, while oxide series materials have low luminance and are insulators, necessitating improved luminescent materials with enhanced stability and efficiency.
Innovation Solution
A luminescent silicate material doped with Ce3+, Tb3+, and Ag ions, specifically formulated as Ln2-x-ySiO5:Ce x, Tb y, Ag z, where Ln is Y, Gd, or Lu, x is between 0 and 0.05, y is between 0.01 and 0.25, and z is between 0 and 0.005, prepared by weighing source compounds and silica aerogel, dissolving, stirring, drying, and sintering under a reducing atmosphere to achieve high stability and luminous efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If sulfide series or oxysulfide series fluorescent powders are used, then luminance is high and electrical conductivity is good, but they decompose into elemental sulfur under large electron beam bombardment, poisoning the cathode tip and producing precipitates that cover the fluorescent powder, reducing luminous efficiency and shortening device life
Solution Approach 1:
The patent changes the chemical composition parameters by using silicate series fluorescent powders with specific ratios of Ln (Y, Gd, La, or Lu), Ce (0.001-0.05), Tb (0.01-0.25), and Ag (0.0001-0.005), which fundamentally alters the material's stability under electron beam bombardment while maintaining high luminance performance
Solution Approach 2:
The patent creates a composite fluorescent powder by combining multiple elements (Ln, Ce, Tb, Ag) in a silicate matrix, where each element contributes specific properties: Ce provides high luminance, Tb enhances color stability, and Ag improves electrical conductivity without compromising stability under electron beam bombardment
2Reliability
If oxide series fluorescent powders are used, then stability is good, but luminous efficiency is not high enough and they are generally insulators
Solution Approach 1:
The patent develops a composite silicate material that combines the stability of oxide series with the high luminance of sulfide series by incorporating Ce, Tb, and Ag elements into a silicate matrix, achieving both high luminous efficiency and stability under electron beam bombardment
Solution Approach 2:
The patent modifies the chemical composition by using silicate-based materials with specific dopant concentrations (Ce: 0.001-0.05, Tb: 0.01-0.25, Ag: 0.0001-0.005), which changes the material's electrical and optical properties to achieve both stability and high luminous 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
The silicate material emits warm white light with improved stability and luminous efficiency, extending the life of field emission devices and simplifying the manufacturing process with a low-cost method.
Implementation Method 1
field emission display has potential advantages in luminance, visual angle, response time, working temperature range, energy consumption and other aspects
Implementation Method 2
luminescent material of silicate, wherein said luminescent material of silicate has a formula of Ln 2-x-y SiO 5 :Ce x ,Tb y ,Ag z
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A luminescent material of silicate is provided. The luminescent material has a formula of Ln2-x-ySiO5:Cex,Tby,Agz, wherein, Ln is one of Y, Gd, La and Lu, 0≤x≤ 0.05, 0.01 ≤ y ≤ 0.25, 0<z≤ 0.005. The method for preparing the luminescent material comprises the following steps: weighing the source compounds of Ln, Ce, Tb, Ag and silica aerogel; dissolving the silica aerogel in the alcoholic solution of the source compound of silver, stirring, drying and sintering to obtain silica aerogel containing Ag; after mixing the weighed source compounds of Ln, Ce, Tb and the silica aerogel containing Ag, sintering under reducing atmosphere to obtain the luminescent material of silicate.