Scientists at North-Caucasus Federal University (SKFU) have successfully developed and patented a compact, highly durable white light source. This innovative device is specifically designed for use in automotive headlights and various types of spotlights. The announcement regarding this breakthrough came from the university`s press service.
According to the university`s specialists, the core component driving this new technology is luminescent ceramics. This advanced material possesses the unique capability to convert incoming light into radiation of a different wavelength, effectively changing its color.
SKFU emphasized that, in addition to its small footprint, the new light source offers exceptional uniformity of emission, setting it apart from existing alternatives. The device emits light with a consistent color temperature across its entire illuminated surface, transforming `blue` light into a stable `white`. This characteristic makes it particularly well-suited for demanding applications in the railway, automotive, and shipbuilding sectors, as well as for theatrical and event spotlights.
The researchers opted to use cerium (Ce) atoms as the key element for this blue-to-white conversion process. When exposed to blue light, cerium atoms emit a broad spectrum of light that includes green, yellow, and red wavelengths.
The resulting `white` light is achieved through the precise mixing of the reflected emission from the original blue laser and the light generated by the ceramic converter. Vitaly Tarala, who heads the research laboratory for advanced materials technology and laser media at SKFU`s Physics and Technology Faculty, explained this process.
«To ensure stable operation of the device, the light converter requires efficient cooling,» Tarala stated. «A portion of the energy from the absorbed excitation light is converted into heat. If this heat builds up, it can reduce the luminescence efficiency. By using ceramics, unlike simpler phosphor layers, heat can spread more evenly throughout the converter and be effectively removed by a cooling circuit. In our current design, the converter, based on cerium-doped yttrium aluminum garnet, is shaped like a cone.»
The strategic use of luminescent ceramics as the radiation converter allows for a significant reduction in the size of the final lighting unit while maintaining impressive brightness levels. Crucially, this technology also provides a substantially longer operational lifespan when compared to devices that rely on traditional powder phosphors.
