A phase-conjugate mirror can be used in Missile countermeasure with significantly improved sensitivity and reliability. It can be also used to produce high-quality images through a turbulent medium for realizing applications in remote sensing. The new LIDAR system to be developed by PI by combining the phase-conjugate mirror with a sensitive detector and a laser has important applications in archaeology, meteorology and atmospheric environment, wind power, geology, physics and astronomy, biology and conservation, military and law enforcement, vehicles, imaging, and 3-D mapping. The phase-conjugate mirrors fully implemented by PI during Phase 2 will meet the requirement of NASA as being defined by the NASA SBIR solicitation of TOPIC: S1 Sensors, Detectors, and Instruments. Specifically, these mirrors will be used to discriminate against the effects caused by cloud in the wavelength ranges of near-IR (1-1.8 microns) and mid-IR (3-4 microns). 3-D imaging systems by combining the mirror, a sensitive detector, and a laser can be used to realize coherent imaging LIDAR for the ASCENDS, DESDynI, LISA, Doppler Wind Lidar, and LIST mission programs after removing the influence caused by cloud. The energy sources of nine infrared luminous galaxies can be diagnosed by a ground-based 3-4 m spectrometer to be developed by PI with a capability of correcting the effects caused by cloud.