Although Venus is the brightest planet in the sky, its surface was long a mystery due to the opacity of its thick atmosphere. Optical images of the planet show a featureless white disk, dominated by scattered sunlight from the impenetrable atmosphere. Radar imaging from Earth provided the first means to see the surface (e.g., Goldstein et al., 1976;Rogers & Ingalls, 1969), but detailed mapping had to await the arrival of orbiting spacecraft with radar capabilities, particularly Magellan (e.g., Solomon et al., 1992).Starting with the work of Allen and Crawford (1984), it was found that it was possible to penetrate the thick Venusian atmosphere by observing nightside thermal emissions in the near infrared (NIR), providing a means to study both the surface and lower atmosphere (

We report a full design process-finite element modeling, fabrication, and characterization-of adaptive doublet polymer lenses. A first-order model was developed and used to design fluidic doublets, analogous to their glass counterparts. Two constant-volume fluidic chambers were enclosed by three flexible membranes, resulting in a variable focal length doublet with a clear aperture of 19.0 mm. Chromatic focal shift was then used to compare numerical modeling to experimentally measured results over a positive focal length range of 55-200 mm (f/2.89 to f/10.5).

The Naval Research Laboratory has developed a new method for generating atmospheric turbulence and a testbed that simulates its aberrations far more inexpensively and with greater fidelity using a Liquid Crystal (LC) Spatial Light Modulator (SLM) than many other methods. This system allows the simulation of atmospheric seeing conditions ranging from very poor to very good and different algorithms may be easily employed on the device for comparison. These simulations can be dynamically generated and modified very quickly and easily. In addition, many models for simulating turbulence often neglect temporal transitions along with different seeing conditions. Using the statistically independent set of Karhunen-Loeve polynomials in conjunction with Kolmogorov statistics in this model provides an accurate spatial and temporal model for simulating turbulence. An added benefit to using a LC SLM is its low cost; and multiple devices can be used to simulate multiple layers of turbulence in a laboratory environment. Current testing with using multiple LC SLMs is under investigation at the Naval Research Laboratory and the Naval Postgraduate School.

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