The accurate measurement of ultrashort pulses is necessary to optimize pulse compression for nonlinear optics and strong-field physics. Additionally, field-sensitive time-domain techniques enable measuring femtosecond and sub-femtosecond dynamics. In this paper, we introduce a single-shot measurement to characterize few-cycle fields. This polarization-sensitive timedomain measurement can retrie...

Small animal models of retinal diseases are important to vision research, and noninvasive high resolution in vivo rodent retinal imaging is becoming an increasingly important tool used in this field. We present a custom Fourier domain optical coherence tomography (FD-OCT) instrument for high resolution imaging of mouse retina. In order to overcome aberrations in the mouse eye, we incorporated a...

A Twyman-Green interferometer is used to measure the phase induced by a liquid-crystal spatial light modulator (LC-SLM) via spatial-carrier phase measurement methods in order to characterize the phase response as a function of applied voltage. With the phase response characterized, the LC-SLM can be operated in a closed-loop adaptive optics system. Four separate phase unwrapping algorithms are ...

We propose a new recursive filtering algorithm for wave-front reconstruction in a large-scale adaptive optics system. An embedding step is used in this recursive filtering algorithm to permit fast methods to be used for wave-front reconstruction on an annular aperture. This embedding step can be used alone with a direct residual error updating procedure or used with the preconditioned conjugate...

This chapter describes the progress in using optical technology to construct high-speed artificial higher order neural network systems. The chapter reviews how optical technology can speed up searches within large databases in order to identify relationships and dependencies between individual data records, such as financial or business time-series, as well as trends and relationships within th...

The software package PHASE includes routines for the propagation of coherent light within the stationary phase approximation (SPA). The code is based on a nonlinear analytic transformation of electric field arrays across longitudinally extended optical elements in normal and grazing-incidence geometries. Recently, the representation of the optical elements (OEs) has been extended to 8 th -order...

OBJECTIVES To elucidate the visual significance of the foveal pit by measuring foveal architecture and function and to reassess use of the term foveal hypoplasia (as visual acuity can vary among patients who lack a pit). METHODS We describe 4 patients who lack a foveal pit. Visual acuities ranged from 20/20 to 20/50. Stratus and Cirrus (Carl Zeiss Meditec, Dublin, California) optical coherenc...

We develop a fast method for solving the one-dimensional wave equation based on geometrical optics. From geometrical optics (e.g., Fourier integral operator theory or WKB approximation) it is known that high-frequency waves split into forward and backward propagating parts, each propagating with the wave speed, with amplitude that is slowly changing depending on the medium coefficients, under t...

The fractional Fourier transform can be optically defined through a phase-space coordinate rotation of the Wigner distribution function associated with the input signal. This operation can be achieved by performing three successive shearing processes, which are reduced to a free-space Fresnel diffraction originated by a scaled version of the input object illuminated with a spherical wave. This ...

Electron optics was born in 1927, when Hans Busch showed that the elementary lens equation is applicable to electron image formation. Interest was soon awakened in France and a book on the subject by Louis de Broglie appeared in 1950. We draw attention to the highlights of electron optics and microscopy over the decades, with particular reference to aberration correction, and to some little kno...