SLED has record breaking optical power
Tyndall National Institute spin-out develops speckle free, surface-emitting blue SLEDs
iSLight, a spin-out company from Tyndall National Institute, Ireland, has developed ground-breaking speckle free, surface-emitting blue SLEDs (high power blue superluminescent LEDs).
The newly developed technology, which will be on show at SPIE Photonics West, in San Francisco (31 January to 2 February 2023), has a world record-breaking peak optical power of around 2.2 W under pulsed operation, with high-resolution beam quality.
Thanks to wafer-scale packaging and testing, the GaN-based SLEDs should also have a lower production cost than commercial lasers maintaining similar power density and efficiency, according to iSLight. In addition, they are more compact and can be scaled in power by going to arrays. Scaling in volume is possible using 100mm diameter GaN wafers.
Applications that could benefit include machine inspection instruments, direct imaging lithography, VR/AR headsets, projection displays, microscopy imaging systems, lighting systems and 3D printing.
SLEDs exploit the process of amplified spontaneous emission (ASE) where the light of spontaneous emission is amplified only in a single pass through an optical waveguide as compared to amplification over multiple roundtrips in an LD. Furthermore, any kind of feedback in the optical cavity is avoided in a SLED, resulting in a broadband spectrum with no amplitude modulation (spectral ripple). Contrary to laser diodes, SLEDs gain increases with the current even much above the transparency conditions.
While the iSLight SLEDS are currently blue (400-450nm), it can also scale to other wavelengths (green, red, infrared).