Image formation from a concave mirror.

Computing locations and extent of images, except in the most trivial configurations or special cases, is a complex task. Even rays emanating from a point source and passing through an optical system generally fail to converge at a single image point, highlighting the care needed to establish image locations. We use three approaches to study image formation in a simple configuration, that of a point source following reflection from a spherical concave mirror.

Imaging in reflecting spheres.

We study the formation of images in a reflective sphere in three configurations using caustics on the field of light rays. The optical wavefront emerging from a source point reaching a subject following passage through the optical system is, in general, a Gaussian surface with partial focus along the two principal directions of the Gaussian surface; i.e.

Determining selected quadratic coefficients in noncentrosymmetric crystals.

We present a systematic theoretical examination concerning the practical possibility of measuring components of the quadratic symmetry tensors for solid materials lacking inversion symmetry. We show that information concerning the quadratic effects in noncentrosymmetrical crystals can be obtained directly by methods that allow for the bypassing of the coexisting dominant linear effects. Here, we deal only with the particular case of the electro-optic effect; however, the results and conclusions are also valid for the elasto-optic effects.

Time-resolved optical transients in tetragonal BaTiO3.

We present and analyze the room temperature (T= 23.5 degrees C) time behavior of the transmitted intensities of polarized light passing through an unclamped (100)-type single crystal of barium titanate (BaTiO3) when subject to a time-dependent, externally applied electric field. To the authors' knowledge, this is the first reported observation and analysis of such time-resolved optical transients.

Method for measuring off-diagonal Kerr coefficients by using polarized light transmission.

We report a method for measuring the off-diagonal coefficients of the quadratic electro-optic (Kerr) tensor by using polarized light transmission. The method relies on designing an experimental configuration in which the linear electro-optic (Pockels) effect does not contribute to the data. Our method can be used to obtain off-diagonal Kerr coefficients for all but two of the 20 crystal point groups for which the Pockels effect and the Kerr effect coexist.

Fraunhofer diffraction to determine the twin angle in single-crystal BaTiO3.

We present a new method for determining the electrically induced twin angle alpha of a (100) bulk single crystal of barium titanate (BaTiO3) using a nondestructive optical technique based on Fraunhofer diffraction. The technique required two steps that were performed simultaneously. First, we analyzed the diffracted light intensity captured with a line camera.

Action from tunable periodic structures. II. Experimental observation of electric field-induced diffraction peaks.

As previously predicted [Appl. Opt. 40, 5583 (2001)], we have now observed electric field-induced diffraction peaks in transmission and reflection experiments by use of a LiNbO3 sample with interdigital planar electrodes that serve as a diffraction grating.