The development and testing of long-wavelength high-power one-dimensional (1D) and two-dimensional (2D) laser diode arrays is being carried out for continuous-wave (CW) and quasi-CW applications.

CW power of 25 W has been obtained from 1.47-µm 1D InP-based diode laser array (Figure 1). The maximum wall-plug efficiency is 37 % at 40 A, and better than 34 % up to the drive current of 60 A. Quasi-CW (5ms 20Hz) power of 110-W has been achieved from 2D diode laser array with full-width-half-maximum of ~8-9 nm (Figure 2).
 
 

Figure 1 Output power (circles) and wall-plug efficiency (squares) of the 1.47-µm 1D array operated in q-CW (open symbols) and CW (closed symbols) modes at coolant temperature of 16 C.

Figure 2 Output power of 2D array operated in the q-CW (5ms 20Hz) mode at 18 C. The inset demonstrates integrated emission spectra of the 2D array at coolant temperatures of 18 C (solid line) and 25 C (dashed line).

High power 2.3-µm GaSb-based diode laser arrays have demonstrated 10 W in CW and 18.5 W in quasi-CW (30µs/300Hz) at a heatsink temperature of 18 C (Figure 3). The maximum power conversion efficiency and internal efficiency are about 9 % and 50 % respectively. The Figure 4 shows the 2D and 1D arrays packaged in water cooled microchannel heatsinks.
 
 
 

Figure 3 Power-current characteristics and wall-plug efficiency of the 2.3-µm laser linear array.

Figure 4 1-D and 2-D arrays packaged in water cooled microchannel heatsinks.