Photorefractive materials combine photoconductive and electro-optic properties: light affects
their electrical conductivity; their optical properties (refractive index, etc.) are affected by …

A novelty filter detects what is new in a scene and may be likened to a temporal high-pass
filter. The current status of optical novelty filters and related devices, based upon four-wave …

A finite-difference technique was used to model photorefractive grating formations in sillenite
crystals under nonstationary recording conditions of applied ac electric fields. These …

The nonlinear differential equations describing the response of photorefractive material to a
moving sinusoidal intensity pattern that permits large modulation depth are solved by a …

Analytic expressions are derived for second-and third-order space-charge fields for a
moving intensity pattern and arbitrary field strengths. The dependence on the spatial …

The photorefractive response with moving gratings is investigated both numerically and
experimentally under varied fringe-velocity and modulation-depth (m= 0.002 to m= 1) …

An analytical solution of the photoconductive material equations for dynamic holographic
gratings of arbitrary contrast has been obtained. A method of measuring high-contrast …

We demonstrate a technique by which components of an image moving with a given speed
and direction may be selectively enhanced. By using the strong grating velocity sensitivity of …

The band transport model is used to derive the space-charge field induced by an optical
beam propagating in photorefractive materials with the application of an external dc field in …

Calibrated optical Bragg‐scattering measurements of the fundamental steady‐state space‐
charge‐field amplitude, and of two higher spatial harmonics, in photorefractive p‐type …