nLight claims another diode laser milestone
nLight, which is developing high-power, high-efficiency lasers based on both GaAs and InP material systems, says that it has set a new world record for output power from a single 1 cm InP laser bar.
A water-cooled InP bar made by the Vancouver, WA, company produced 88 W of continuous-wave power at 1470 nm.
The significance of the breakthrough, says nLight, is that diode bars based on the technology could substantially improve high-power diode-pumped solid-state (DPSS) lasers that emit in the so-called "eye-safe" 1400-1600 nm range.
These large laser systems are usually pumped with high-power GaAs diodes emitting around the 800 nm range. However, they require an additional system, known as an optical parametric oscillator (OPO), to shift the output wavelength into the eye-safe range.
Using InP-based diode bars, say nLight, means that an OPO is not needed. That's because the 1470 nm output can be used to pump an erbium-doped crystal, which naturally emits in the eye-safe range. And so the DPSS systems can be made smaller and more cheaply, and so should be able to penetrate more applications.
The physics of the erbium-doped crystal structure also means that less pumping power is required: "The number of diode laser bars required to reach a given pulse energy [with an erbium-doped crystal] is reduced by at least an order of magnitude," claimed the company.
