Conventional laser diodes are not routinely used for most heating applications since the output power density is generally too high and the irradiation area too small. Whilst it is possible to resolve these issues with clever optical design, such as homogenisation and expansion of the beam, a complex optical lens assembly is required, which makes the system bulky, fragile, and expensive. Just as LEDs are now replacing incandescent lamps and general lighting lamps, VCSELs (Vertical Cavity Surface Emitting Lasers) will become the next generation of heating lamps due to significantly higher efficiency and reliability. In terms of manufacturing and integrated packaging processes, VCSELs as a heat source and LED as a light source have many similarities, and both have cost advantages.
VCSELs can provide very uniform illumination and can be scaled to an area of any size without any special optical design. VCSELs are very compact and can precisely control heat. For material processing, narrow spectral characteristics allow VCSELs to match the specific absorption spectrum of the material being processed, thereby further improving the overall efficiency. VCSELs are inherently reliable and utilise similar packaging to LEDs enabling high reliability and the ability to work in harsh environments. The image shows the layout of dense VCSEL array with high output power.
Powerful VCSEL arrays can be formed by integrating multiple chips such as the 25 X 11mm2 array. This contains 40 chips of 1.5 X 1.5mm2 and outputs over 300 Watts of continuous (CW) power and more than 1000W of quasi-continuous (QCW) power with a power conversion efficiency of more than 50%.
LASER COMPONENTS offers a wide range of VCSELs for various applications.