An improvement over both vertical-cavity surface-emitting laser diodes (
VCSEL) and edge-emitting laser
diodes, the Vertical-Emission
Laser (VEL) is a scalable device that can be combined in easily-cooled
planar arrays for high-output power levels.
Offering a low-cost replacement to edge-emitting laser stacks, the devices from optoelectronics developer Quintessence Photonics (Sylmar, CA) are able to operate in 2-D arrays of almost unlimited size with improved assembly, testing, and cooling over arrays created with edge-emitting devices. Successfully tested in a 3-row 75-laser array delivering over 100 Watts, the VEL promises to displace edge-emitting laser stacks in pump and other power laser applications.
Using a total-internal-reflection mirror design, the prototype device has a vertical emission similar to that of a VCSEL, but with a better thermal impedance and reduced electrical resistance for increased power. Complete water-cooled components can for the first time be constructed in flat, simple geometries, as VEL arrays can be manufactured, tested, wired, and packaged while still on the original wafer, with only one cooler needed for the entire array instead of the one cooler per stack required for edge-emitting-laser-based bars.
The prototype 2-D array emits 270 Watts per square centimeter, and the VEL platform is scalable to 1,000 W/cm2 or more. Operating in the eye-safe 1,400 to 1,500-nm range, individual diodes have a horizontal emission angle of 5°, a vertical angle of 35°, and spectral bandwidth of 0.6 nm.