Precision current control for quantum cascade lasers as flight calibration sources.

摘要

A space-grade-equivalent precision current controller for quantum cascade lasers (QCLs) is presented. This current controller design will enable constant wave (CW) or pulsed mode operation of QCL devices as calibration sources in a space environment. One major source of sensitivity in current controllers is temperature variation across the electronics board. This design integrates some methods used by Pacific Northwest National Laboratory (PNNL) to compensate for these sensitivites. An uncertainty analysis of the key components of the space-grade-equivialent current controller was performed to estimate changes in QCL output power due to a change of 1°C. The performed uncertainty analysis shows that the design has the capability to control the current to within the 0.1% output power stability goal with a change of +/-10°C in the precision current controller electronics.