Ce:LYSO, from scintillator to solid-state lighting as a blue luminescent concentrator

Area of Science:

• Solid-state lighting
• Optical materials science
• Luminescent concentrators

Background:

• Cerium-doped lutetium-yttrium oxyorthosilicate (Ce:LYSO) is a scintillator for medical imaging and security scanners.
• Advancements in UV LEDs create opportunities for Ce:LYSO as a novel LED-pumped solid-state light source.
• Large-size Ce:LYSO crystals are available, prompting investigation into their use as luminescent concentrators.

Purpose of the Study:

• To investigate the performance of Ce:LYSO as a luminescent concentrator for solid-state lighting.
• To analyze the spectroscopic properties influencing Ce:LYSO's efficiency in luminescent concentration.
• To evaluate Ce:LYSO's potential as an innovative light source for illumination and imaging applications.

Main Methods:

• Extensive performance study correlated with spectroscopic properties of Ce:LYSO crystals.
• Comparison of Ce:LYSO efficiency with Ce:YAG for luminescent concentration.
• Characterization of spectral output, peak power, and brightness under UV LED pumping.

Main Results:

• Ce:LYSO demonstrated lower luminescent concentration efficiency compared to Ce:YAG due to limited quantum efficiency and self-absorption losses.
• A Ce:LYSO crystal (1×22×105 mm³) pumped with 3400 W UV LED delivered a broadband spectrum (430 nm center, 60 nm FWHM).
• The Ce:LYSO concentrator achieved a peak output power of 116 W and a brightness of 509 W cm⁻² sr⁻¹ on a 1x1 mm² surface, exceeding blue LEDs.

Conclusions:

• Ce:LYSO exhibits potential as an innovative solid-state light source for illumination, particularly for imaging applications.
• While less efficient than Ce:YAG for luminescent concentration, Ce:LYSO's unique spectral power and brightness offer distinct advantages.
• Further research into optimizing Ce:LYSO for luminescent concentration could enhance its viability for advanced lighting solutions.