Mid-Infrared LIDAR for Small Spacecraft

In this SBIR program, Omega Optics, University of Texas, at Austin and at San Antonio, propose chip-integrated two-dimensional (2D) non-mechanical optical LIDAR at 4.6 micron wavelength for small spacecraft in the AEHR Satellite Program. 2D wide angle steering is achieved by thermal phase shifting in azimuth and quantum cascade laser (QCL) wavelength tuning in elevation planes. The monolithic epitaxial structure, with no wafer bonding, comprises a QCL active region grown on top of a passive underlying InGaAs waveguide. An unequally spaced grating array with emitter spacing limited by optical crosstalk between adjacent elements, results in a single far field lobe with narrow beam width and large side lobe reduction. Our demonstrated dual waveguide structure, adiabatically transfers the QCL mode to passive InGaAs waveguide where light is split among emitter elements for antenna emission to free space. Quantum cascade detector (QCD) arrays biased on the same epi, work in receiver mode to detect the reflected light in direct detection or continuous wave frequency modulated schemes. Scalable data fusion algorithms based on artificial intelligence will utilize limited and local information obtained from sensor swarms for more accurate knowledge. Weaker signals can be detected due to 15-20 times lower solar irradiance than near-infrared.