VCSELs (vertical cavity surface emitting lasers) is a new technology for pumping of solid state lasers, including fiber lasers. Because of their circular beam and excellent optical characteristics, it is possible to make high brightness pumps using an array of closely spaced single mode VCSEL devices. The arrays are temperature stable and operate at high temperatures without chillers. They are lower cost as they do not need expensive operations like cleaving of the wafers. These fiber coupled arrays can be combined for higher output power using fiber combiners and coupled with double core fiber to develop small, high performance fiber lasers working at elevated temperatures without chillers.
Advantages of the VCSELs for fiber laser pumping applications are the following:
(i) Circular beam output and ease of coupling with fiber-individual VCSEL devices and arrays are known for easier coupling to fibers because of their circular beam and does not need complicated beam shaping optics. It is possible to couple them to fibers with very high efficiency.
(ii) Can be operated at high temperature without refrigeration- can be operated at temperatures to 80 degC, and are cooled by a water pump and fan/radiator combination similar to the way the automobile engines are cooled. The cooling system becomes very small, rugged and portable with this approach.
(iii) Higher power from the array- VCSELs arrays are now delivering 230W from a 4.7 x 4.7mm aperture (>1kW/ cm2)- and by fabricating a large 10x10mm array with the same power density we can obtain >1kW power which can be coupled to a fiber.
(iv) Higher reliability and life expectancy (50x) than edge emitters , resulting from removal of the junction from the emission facet and lower output power-density. This greatly reduces the maintenance needs and increases the life expectancy of solid state and fiber lasers which is dominated by pump life.
(v) Superior linewidth and stability, The typical linewidth from a 200W array is <0.8nm and temperature dependence is 0.06nm/deg C which are both much better compared to the edge emitters- highly beneficial to most solid state laser systems.
(vi) Much lower cost of gallium arsenide VCSEL chips and pump modules, resulting from gallium arsenide IC chip like manufacturing technology and similar simple packaging technique. The VCSELs already replaced the edge emitters in the low power applications for their lower cost, beam quality and high reliability. They can be 10x lower cost compared to the edge emitters as has been the case in the low power applications.
Brandnew's VCSEL product line：
Package: Die, SMD, TO, ST
Wavelength: 638nm, 808nm, 850nm, 940nm
Power: From mW level to W level
Function optional: Photodiode
More details, pls contact us via Email or Whatsapp:
Whatsapp/Skype/Wechat: 0086 181 5840 0345
Email: info@brandnew-china.com