Front-efficiency enhanced composite structure ceramic phosphor for high-power laser lighting and display applications

Area of Science:

• Materials Science
• Optoelectronics
• Photonics

Background:

• Composite ceramic phosphors offer high luminous efficiency and thermal stability for laser lighting.
• Refractive index mismatch limits forward light extraction, and thermal pathways need improvement for high-power blue laser applications.

Purpose of the Study:

• To enhance light extraction and thermal management in composite ceramic phosphors for laser-driven lighting and display applications.
• To develop a composite structure phosphor addressing refractive index mismatch and thermal conduction limitations.

Main Methods:

• A composite structure phosphor was designed, integrating composite ceramics (YAG/Al2O3-Ce:LuAG) with optical adhesive and glass lenses.
• The refractive index gradient and thermal pathways were optimized through this composite architecture.

Main Results:

• Forward light extraction efficiency was increased to 24.5%, with luminous efficiency reaching 231 lm/W.
• The beam angle was narrowed to 6.2°, and the structure withstood 48.4 W/mm2 blue laser irradiation without saturation.
• A luminous flux of 5196 lm was achieved under 28.1 W excitation.

Conclusions:

• The proposed composite structure phosphor effectively improves front-efficiency for laser lighting and display applications.
• This architecture provides a viable solution for enhanced light extraction and thermal management in demanding laser applications.