Vertical Cavity Surface Emitting Laser (VCSEL) — surface-emitting laser with vertical-cavity semiconductor laser diode is a type of emitting the light in the direction perpendicular to the surface of the chip, as opposed to edge-emitting laser diodes, radiating in a plane parallel to the surface.
The main advantages of VCSEL in comparison with traditional edge-emitting semiconductor lasers are small angular divergence and symmetric radiation pattern output optical radiation, temperature and radiation stability, group technology and the ability to test the devices directly on the plate. Planar VCSEL technology allows creating VCSEL arrays - linear arrays and two-dimensional matrices with a large number of individually addressable VCSEL emitters.
VCSEL is used primarily for high rate telecom applications, it refers to the VCSEL structure of GaAs (850 nm) and InP (IR band 1270-2360 nm). In addition the IR VCSEL are used for the purpose of optical gas analysis. Particularly promising are tunable VCSEL.
In spite of the high temperature stability, however, the emitting power, spectral line of radiation have strong temperature dependency. Therefore, in many of these applications thermostabilization is applied widely to ensure the stability of the operational parameters, as well as for longer lifetime.
Features for thermal management task of VCSEL are the following:
Progress on creating of powerful vertical lasers, for example, Vertical-External Cavity Surface-Emitting Lasers (VECSEL), requires a more powerful cooling. VCSEL arrays require more powerful cooling solutions in terms of cooling capacity.
Thermoelectric coolers as solid-stage heat pumps give a unique reliability at several hundred thousand hours of continuous operation. It is more than 20-25 years of operation without maintenance, replacement, which is important for telecommunication systems.
RMT has specially developed and produce series of miniature powerful TECs optimal for cooling of VCSEL.
For ultra-miniature VCSEL design RMT recommends TEC Series 1MD04, and . The smallest TECs of the series are just a little more than a square millimeter footprint. That allows the TECs use for cooled VCSELs in small packages such as TO-37, and very miniature types like , TO56 and some others.
To select suitable solution and the optimal TEC for an application, the is available at RMT’s website. For detailed modeling and calculations the company RMT provides our customers by free software or .And for advice and assistance.