New LED-based high-brightness incoherent light source in the SWIR

Area of Science:

• Optics and Photonics
• Materials Science

Background:

• Luminescent concentrators (LCs) are optical devices that absorb and re-emit light.
• Short-wave infrared (SWIR) applications require efficient light sources and concentrators.
• Previous LC systems have limitations in terms of cost and efficiency for SWIR emission.

Purpose of the Study:

• To develop and characterize the first LED-pumped luminescent concentrator (LC) operating in the short-wave infrared (SWIR) spectrum.
• To optimize the optical conversion efficiency of the SWIR LC system.
• To compare the performance of the developed LC with existing LED technologies.

Main Methods:

• Utilized low-cost 940 nm LEDs to pump a Ytterbium and Erbium doped glass (Yb,Er:Glass) LC.
• Employed a total of 128 LEDs with a combined pump power of 66 W.
• Investigated various optical configurations to optimize output power and efficiency.
• Measured the output power and radiance from a 100-mm-long LC in a continuous wave regime.

Main Results:

• Achieved an output power of 850 mW from a 2.5 x 2 mm² LC emitting surface.
• Obtained an optical conversion efficiency of 1.29%.
• Demonstrated a radiance performance one order of magnitude higher than LEDs emitting at the same wavelength.

Conclusions:

• The developed LED-pumped SWIR LC represents a significant advancement in optical power conversion.
• The system offers a cost-effective and highly efficient solution for SWIR applications.
• This technology shows superior radiance compared to conventional LEDs in the SWIR range.