Cloud discrimination for ASCENDS Mission Based on Optical Phase Conjugation as a Novel Approach

PI at ArkLight proposes a novel scheme for making cloud discrimination in the wavelength ranges of near-IR (1-1.8µm) and mid-IR (3-4 µm). This scheme is based on optical phase conjugation from a second-order nonlinear medium. It overcomes the disadvantages of slow speed in photorefractive media and poor reflectivities in third-order nonlinear materials. During Phase 1, she will design novel phase-conjugate mirrors operating at the signal wavelengths of 1.27 µm and 1.57 µm. Subsequently, she will fabricate the designed phase-conjugate devices. The next step will be testing of the fabricated devices by investigating sum-frequency and difference-frequency generation in the transverse geometry. She will also carry out modeling efforts on the device performances for making cloud discrimination. This Phase 1 project will be carried out in collaboration with Prof. Ding at Lehigh University who is one of the pioneers in optical phase conjugation. The anticipated results for Phase 2 include implementation and testing of the phase-conjugate mirrors operating at 1.27 µm and 1.57 µm for correcting phase distortion and making cloud discrimination, optimization of the phase-conjugate mirrors, finding solutions to practical issues for deploying these mirrors in the ASCENDS mission, expansion of input wavelengths, incorporation with frequency up-conversion devices, and reports.