Semiconductor-based widely tunable lasers are attractive in that they are capable of wavelength switching on short timescales (<10ns); however, in order to switch at those speeds and remain stable, sophisticated control electronics and strategies are required. The traditional approach to achieving switching speeds on the order of 100ns is to use an FPGA that interfaces to multiple digital to analog converters via a high-speed interface, resulting in a relatively large footprint and high power consumption (10s of watts not including the laser itself). In our proposed approach, we suggest using our proprietary semiconductor devices that provide on-chip thermal compensation to remove the sensitivities to changing injection current, in conjunction with high-speed, low power consumption direct digital synthesis waveform generation integrated circuits. This will result in a small footprint (approximately 2.7” x 3.4” x 0.54”) module that consumes less than 10W total (including laser and thermoelectric cooler). This solution will enable volume and power constrained applications to adopt the capabilities that widely tunable laser source modules have to offer. These applications include lidar (employing wavelength sensitive beam steering elements and/or FMCW), atmospheric gas sensing (methane, etc.), and fiber sensing.
The proposed innovation directly supports multiple NASA interests including lidar, atmospheric gas sensing, and fiber sensing.
The proposed innovation directly supports multiple market interests including lidar, atmospheric gas sensing, and fiber sensing, and metrology.