Study On The Preparation And Optical Properties Of Red Or Composite Fluorescent Glass For White LED/LD With High Color Rendering Index

In order to meet the demanding requirements of laser（LD）devices（>1000 W/cm²）on the thermal conductivity and physical and chemical stability of the fluorescent converter,people have proposed fluorescent glass,fluorescent crystal,fluorescent transparent ceramic and other forms of fluorescent blocks material used as an all-inorganic fluorescence converter.Among them,fluorescent glass and fluorescent ceramics are considered to be excellent for laser lighting and display due to their excellent comprehensive performance such as high quantum efficiency（>80%）,high thermal conductivity（4-15 W/m/K）,and good thermal shock resistance.Compared with other fluorescent materials,fluorescent glass has become the mainstream of popular choice because of its low sintering temperature,simple preparation conditions,and low cost.However,most of the current researches focus on yellow YAG:Ce fluorescent glass,and there is very little research on nitride red fluorescent glass.In addition,single-color YAG:Ce fluorescent glass is used for LED/LD.The color temperature is usually higher than 4500 K and the color rendering index（CRI）is lower than 80.This is due to the lack of a red component supplement,which greatly limits it’s competing in high-quality indoor lighting.In order to solve the above problems,this article chooses to prepare high-stability nitride red light glass and composite fluorescent glass by low-temperature sintering,and successfully applies the prepared fluorescent glass to advanced lighting fields such as LED and LD to obtain high luminous efficiency and high lumen,high color rendering effect.Based on the above research points,this paper mainly includes the following parts:1.A series of concentration gradient and temperature gradient CaAlSiN₃:Eu²⁺fluorescent glass（CASN-Pi G）successfully prepared using low-temperature sintering technology to mix SiO₂-B₂O₃-Na₂CO₃-Ca O glass and CaAlSiN₃:Eu²⁺phosphors uniformly,The prepared CASN-Pi G maintains high quantum efficiency,and it has excellent optical performance and stability in a thermal environment and can achieve high lumen flux under high power density.2.CaAlSiN₃:Eu²⁺phosphor,Lu₃Al₅O₁₂:Ce³⁺（Lu AG）phosphor and SiO₂-B₂O₃-Na₂CO₃-Ca O glass are uniformly mixed to prepare Lu AG&CASN-Pi Gs fluorescent glass by low-temperature sintering technology.The prepared Lu AG&CASN-Pi Gs obtained high-quality white light in w LDs（Ra=95）.More importantly,the luminous efficiency of LD with a heat sink based on Lu AG&CASN-Pi G is as high as 216.79 lm W^-1.This makes the prepared Lu AG&CASN-Pi G have great application potential in solid-state laser light sources.