Nitrogen-Containing Phosphor for White LED Color Rendering

The patent combines multiple phosphor materials (garnet-based yellow phosphor, phosphor with yellow to red emission peak, and phosphor containing nitrogen) to create a composite phosphor system. This composite approach allows the system to maintain high luminance from the blue LED and yellow phosphor while adding red light emission through the red-emitting phosphor components, thereby improving color rendering properties without sacrificing luminance.

The patent divides the illumination system into multiple functional components: a high luminance blue LED source, a garnet-based yellow phosphor for converting blue to yellow light, and additional phosphors (including red-emitting phosphors and nitrogen-containing phosphors) for enhancing specific wavelength ranges. This segmentation allows each component to be optimized for its specific function while working together to achieve both high luminance and excellent color rendering.

The patent modifies the phosphor composition parameters by incorporating phosphors with broad emission spectra and flat excitation bands. The nitrogen-containing phosphor and red-emitting phosphor are selected to have emission characteristics that complement the garnet-based yellow phosphor, creating a more stable overall emission profile. This parameter optimization reduces sensitivity to variations in individual phosphor performance, thereby improving color tone consistency.

The patent employs a phosphor combination where the broad emission spectrum and flat excitation band characteristics provide inherent feedback stabilization. The nitrogen-containing phosphor and red-emitting phosphor act as buffer components that compensate for fluctuations in the garnet-based yellow phosphor's emission intensity and peak wavelength, maintaining consistent color output through the synergistic interaction of multiple phosphor materials.