Although biological cells are mostly transparent, they are phase objects that differ in shape and refractive index. Any image that is projected through layers of randomly oriented cells will normally be distorted by refraction, reflection, and scattering. Counterintuitively, the retina of the vertebrate eye is inverted with respect to its optical function and light must pass through several tis...

The concept of filtered Microwave Photonic Links is proposed in order to provide the most general and versatile description of complex analog photonic systems. We develop a field propagation model where a global optical filter, characterized by its optical transfer function, embraces all the intermediate optical components in a linear link. We assume a non-monochromatic light source characteriz...

A principle of direct volume rendering is that visualizations can be created without creating intermediate geometric structure, such as polygons comprising an isosurface, but simply by a “direct” mapping from volume data points to composited image elements. Together with traditional computer graphics elements such as camera, lighting, and shading, the central ingredient in that direct mapping i...

PURPOSE To evaluate how ocular optical image quality and psychophysical estimates of visual performance compare to each other as a function of defocus. METHODS We measured the optical modulation transfer function using a double-pass apparatus and psychophysical estimates of visual performance: contrast sensitivity function (CSF) and visual acuity. Both sets of data were obtained under the sam...

Superresolution microscopy enables imaging in the optical far field with ~20 nm-scale resolution. However, classical concepts of resolution using point-spread and modulation-transfer functions fail to describe the physical limits of superresolution techniques based on stochastic localization of single emitters. Prior treatments of stochastic localization microscopy have defined how accurately a...

We use the radiative transfer model and chemistry transport model to improve our retrievals of dust optical properties from satellite measurements. The optical depth and absorbing optical depth of mineral dust can be obtained from our improved retrieval algorithm. We find the nonsphericity and absorption of dust particles strongly affect the scattering signatures such as phase function and pola...

An optimal artificial neural network (ANN) has been developed to predict the Nusselt number of non-Newtonian nanofluids. The resulting ANN is a multi-layer perceptron with two hidden layers consisting of six and nine neurons, respectively. The tangent sigmoid transfer function is the best for both hidden layers and the linear transfer function is the best transfer function for the output layer....

We present a batteryless, 27uW barely subcutaneous sensing platform using optical power and data links. We demonstrate an 8.1 mm x 3.2 mm implantable tag powered by an 850nm infrared source through the skin barrier. Measurements using pig skin indicate that optical power transfer through skin achieves a 4.9% efficiency, which is higher than mm scale inductive power links. As a proof-of-concept ...