A new approach to three-dimensional tumor localization in turbid media with the use of measurements in a single plane is presented. Optical diffuse photon-density waves are used to probe the turbid medium. Relative amplitudes and phases are measured in the detection plane. Lateral localization is accomplished in the detection plane. With a Fourier optics approach, the scattered wave is reconstructed throughout the volume to provide depth localization. Computer-simulation results that validate this technique are presented. Applications of this technique to multiple tumors and to optical mammography are discussed.

Large aperture space telescopes are built with low F#'s to accommodate the mechanical constraints of launch vehicles and to reduce resonance frequencies of the on-orbit system. Inherent with these low F# is Fresnel polarization which effects image quality. We present the design and modeling of a nano-structure consisting of birefringent layers. Analysis shows a device that functions across a 400nm bandwidth tunable from 300nm to 1200nm. This Fresnel compensator device has a cross leakage of less than 0.001 retardance.

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Current state-of-the-art commercial sensors and actuators do not meet many of NASA's next generation spacecraft and instrument needs. Nor do they satisfy the DoD needs for satellite missions, especially micro/nano satellite missions. In an effort to develop advanced optical devices and instruments that meet mission requirements, NASA Langley recently completed construction of a new cleanroom housing equipment capable of fabricating high performance active optic and adaptive optic technologies including deformable mirrors, reconfigurable lenses (both refractive and diffractive), spectrometers, spectro-polarimeters, tunable filters and many other active optic devices. In addition to performance, these advanced optic technologies offer advantages in speed, size, weight, power consumption, and radiation tolerance. The active optic devices described in this paper rely on birefringent liquid crystal materials to alter either the phase or the polarization of the incoming light. Design considerations and performance evaluation results for various NASA applications are presented. Applications presented will include large space telescopes, optical communications, spacecraft windows, coronagraphs, and star trackers.