High-power Vertical-cavity Surface-emitting Laser Arrays Research Articles

Establishing equivalent circuits of mounted, high-power VCSEL arrays for iToF cameras

Solid-state indirect time-of-flight (iToF) cameras are crucial to numerous short-to-medium-range applications, owing to their advantages in terms of system integrability and long-term reliability. However, due to the low light intensity, the sensing range of iToF cameras is generally limited to a few meters, which hinders their wide applications. Further increasing the sensing range requires not only higher-power laser diodes but also well-designed driver circuits, which are based on prior knowledge of the laser diodes’ equivalent circuits (ECs). However, experimental studies on ECs of a mounted, high-power vertical-cavity surface-emitting laser (VCSEL) array that comprehensively incorporates all parasitic components, especially parasitic stemming from printed circuit boards (PCBs), remain absent. In this Letter, an 850 nm VCSEL array with a 15.3 W peak power and a 581 MHz bandwidth is fabricated, and more importantly, its EC is experimentally established. Leveraging the accurate EC, a compact iToF camera with a sensing range up to 11.50 m is designed. In addition, a modified precision model is proposed to better evaluate the iToF camera’s performance.

High-power VCSEL arrays for emission in the watt regime at room temperature

Selectively oxidized InGaAs vertical-cavity surface emitting lasers (VCSELs) at an emission wavelength of /spl lambda/=980 mm are investigated for high-power applications. Densely packed arrays consisting of 19 single devices with an active diameter of 50 /spl mu/m emit 1.08 W of continuous-wave (CW) optical output power at room temperature. At 10/spl deg/C, heat sink temperature the output power increases to 1.4 W, which corresponds to a chip size averaged power density of 1 kW/spl middot/cm/sup 2/. Low divergence angle of less than 16/spl deg/ full-width at half-maximum (FWHM) and the circularly symmetric far-field pattern allow for simple focusing of the beam with power densities above 10 kW/spl middot/cm/sup 2/.