wavelength conversion device

Abstract

The present invention relates to a wavelength conversion device. The wavelength conversion device comprises a first light-emitting layer and a second light-emitting layer stacked. The first light-emitting layer is located on the light incident side and has a light-incident surface. The second light-emitting layer It is located on the light exit side and has a light exit surface. The first luminescent layer is formed of at least first phosphor powder and glass powder, the second luminescent layer is formed of at least second phosphor powder and glass powder, and the particle size of the first phosphor powder is larger than that of the second phosphor powder particle size. A volume ratio of the first phosphor powder to the glass powder in the first light-emitting layer is smaller than a volume ratio of the second phosphor powder to the glass powder in the second light-emitting layer. According to the wavelength conversion device of the present invention, the occurrence of the thermal quenching phenomenon of the luminescent center can be reduced and the light extraction efficiency can be improved.

Description

technical field [0001] The present invention relates to the field of projection display, in particular, to a wavelength conversion device. Background technique [0002] In recent years, laser projection equipment has gradually gained people's attention. In such a device, the fluorescent material is excited by excitation light with a first wavelength such as a laser diode (LD, Laser Diode) or a light emitting diode (LED, Light Emitting Diode), thereby producing a high-brightness light having a second wavelength. of excited fluorescence. In the above-mentioned wavelength conversion process, if high conversion efficiency is to be achieved, the luminescent center (ie, phosphor particle) in the fluorescent material needs to have high quantum efficiency and less thermal quenching phenomenon, and also Fluorescent materials are required to have high light extraction efficiency. At present, the quantum efficiency of commercial phosphors such as YAG:Ce and LuAG:Ce has reached more ...

AI Technical Summary

Problems solved by technology

In the case of silica gel packaging, although it can provide a better distribution effect of the luminescent center, the heat dissipation of the silica gel material is poor, resulting in poor thermal stability of the device.

In the case of glass packaging, the ratio of phosphor powder to glass powder directly affects the light conversion efficiency of the device. When the ratio of phosphor powder: glass powder is small, the light efficiency of the wavelength conversion device is low; when phosphor powder: glass powder When the ratio of the wavelength conversion device is larger, the optical efficiency of the wavelength conversion device is higher, but with the increase of the laser optical power, the thermal saturation phenomenon will become more and more serious.

Images