Toshiba develops 200 mW violet laser diode
Blue-violet lasers for next-generation optical disc players and drives must achieve high optical output power, low noise performance and a stable beam profile if they are to read and write the densely-packed data on next-generation optical discs. This is particularly true in cases of dual-layer-disc recording and high-speed recording, both of which require a more powerful laser source than single-layer, standard-speed recording.
As well as having an optical output power of 200 mW in continuous-wave (CW) mode at 25C, Toshiba’s laser has a noise level of –132 dB/Hz at 3 mW. These characteristics are attributed in part to Toshiba’s facet coating technology.
Also, the company says that it has achieved high quantum efficiency through the precise optimization of doping levels within the laser structure, which results in a lower operating current at higher optical power output.
The 409 nm laser has a threshold current of 35 mA and an operating current of 164 mA. The beam angle is 12.4 degrees in the parallel direction, and 25.8 degrees in the perpendicular direction.
Toshiba will exhibit the new laser diode at the CEATEC show to be held at Makuhari Messe, Chiba prefecture, from October 7-11.
