We report a single-step lithographic approach for precisely mapping near field light diffraction in photoresist and fabricating complex subwavelength structures. This method relies on the diffraction of UV light from opaque patterns on a photomask, and utilizes the central diffraction maximum (known as the 'Poisson spot' for an opaque disk) and its higher orders. By correlating pattern geometri...

We investigate the phase behavior of a two-dimensional suspension of charge stabilized polystyrene spheres in the presence of a one-dimensional periodic light field. With increasing light intensity we observe a liquid-solid followed by a solid-liquid transition which are known as laser-induced freezing and melting, respectively. Here we report on measurements where, in addition to the light int...

Photo-assisted one-step electrodeposition has been applied to help in forming smooth and dense CuInSe2 films. The difference in surface morphology and crystalline quality between CuInSe2 films with various photo-assistance has been investigated. In the photo-assisted electrodeposition process, the many kinds of lamps providing maximum light intensity at about 380 to 620 nm were used as light so...

We study formation and interaction of one-dimensional screening solitons in a photorefractive medium with sublinear dependence of the photoconductivity on light intensity. We find an exact analytical solution to the corresponding nonlinear Schrodinger equation. We show that these solitons are stable in propagation and their interaction is generic for solitons of saturable nonlinearity. In parti...

Animals estimate visual motion by integrating light intensity information over time and space. The integration requires nonlinear processing, which makes motion estimation circuitry sensitive to specific spatiotemporal correlations that signify visual motion. Classical models of motion estimation weight these correlations to produce direction-selective signals. However, the correlational algori...

1. Extensive measurements have been obtained (a) relating photosynthesis and light intensity for a large range of CO(2) concentrations and (b) relating photosynthesis and CO(2) at different light intensities. From these families of curves, the limiting factor relationship can be secured for any value of the photosynthesis rate. 2. In terms of previous work an equation has been derived for descr...

A concise theoretical treatment is developed for the calculation of mean time, differential pathlength, phase shift, modulation depth and integrated intensity of measurements of light intensity as a function of time on the surface of tissue, resulting from either the input of picosecond light pulses, or radio frequency-modulated light. The treatment uses the Green's function of the diffusion ap...

Many applications can benefit from the use of pupil filters for controlling the light intensity distribution near the focus of an optical system. Most of the design methods for such filters are based on a second-order expansion of the Point Spread Function (PSF). Here, we present a new procedure for designing radially-symmetric pupil filters. It is more precise than previous procedures as it co...

The Drosophila photoreceptor potential is thought to be composed of discrete unit potentials called bumps. The steady-state receptor potential and the accompanying voltage fluctuations were recorded intracellularly under steady illumination. The occurrence rate, effective amplitude, and duration of the bumps were deduced by assuming a shot noise model. Over a wide range of light intensity, the ...

We model the polarization-dependent photocontractions of polydomain nematic elastomers. Contraction initially arises by light-induced director rotation. At higher light intensity, strain recovers because the local order parameter diminishes. Thus we predict photostrains to be nonmonotonic with light intensity and predict the induction of a negative global order parameter for the system of polyd...