Recent Improvement in Nitride Lasers

We report our recent improvement of watt class blue and green GaN based LDs. These LDs were grown on c-face GaN substrates by metal organic chemical deposition. The laser chip was mounted on the heat sink by the junction down method in TO-empty set9 mm package for the suppression of the thermal resistance. The optical output power of 455nm blue LDs was obtained above 4.7 W at injection current of 3A. The average lifetime was estimated to be over 30,000 hours at case temperature of 65 degree C under 3A. In green LDs, 1 watt class 532 nm green LDs as same wavelength as second harmonic generation (SHG) green laser was developed and the wall plug efficiency was 12.1 %. And the longer lasing wavelength was achieved to 537 nm.