A novel narrow-band red-emitting phosphor for lighting and backlight display

Area of Science:

• Materials Science
• Solid-State Lighting
• Display Technology

Background:

• White light-emitting diodes (LEDs) are widely used for indoor lighting.
• Stable narrow-band red-emitting phosphors are essential for advanced liquid crystal display (LCD) backlights.

Purpose of the Study:

• To develop a novel narrow-band red-emitting phosphor for enhanced white LEDs and wide-gamut displays.
• To improve the color rendering index (CRI) and display color gamut.

Main Methods:

• Synthesis and characterization of a novel CaGdGaO4:Eu2+ phosphor.
• Evaluation of its photoluminescence properties, thermal stability, and quantum efficiency.
• Fabrication of white LED devices and backlight units incorporating the phosphor.

Main Results:

• The CaGdGaO4:Eu2+ phosphor exhibits a narrow red emission peak at 636 nm (FWHM 58 nm) under 470 nm excitation.
• It shows high thermal stability (68.5%@423 K) and 48.9% inner quantum efficiency.
• White LEDs integrated with this phosphor achieved a CRI of 96.3 and a correlated color temperature of 3854 K.
• A stable red-emitting composite film and a white LED backlight with an expanded color gamut were successfully constructed.

Conclusions:

• The novel CaGdGaO4:Eu2+ phosphor is a promising candidate for high-quality warm white LED illumination.
• Its narrow-band red emission is suitable for achieving wide-gamut backlight displays.
• The developed phosphor demonstrates significant potential for both lighting and display applications.