Intense combinatorial study of balanced incomplete block designs since the time of Fisher and Yates has led to a great many designs with the same numbers of treatments, blocks, and block size. While the basic analysis does not differentiate among different BIBDs with the same parameters, they do differ in their capacity to withstand loss of experimental material. Competing BIBDs are compared he...

Considering general prime or prime powered factorials, we give a nite projective geometric formulation for regular fractional factorial split-plot designs. This provides a uniied framework for such designs and facilitates their systematic study under the criteria of minimum aberration and minimum secondary aberration; the latter criterion is introduced to achieve ner discrimination. We investig...

The wave-front aberration of the human eye was measured for eight subjects using a spatially resolved refractometer (a psychophysical ray-tracing test). The eyes were undilated and presented with accommodative stimuli varying from 0 to -6 diopters. Monochromatic wave-front aberrations tend to increase with increasing levels of accommodation, although there are substantial individual variations ...

PURPOSE To examine the dynamics of the tear film in patients with dry eye by measuring the wavefront aberrations of the anterior surface of the film. METHODS Anterior surface aberrations for a 7-mm pupil were determined in 13 patients with dry eye at 1-second time intervals, for 15 seconds after a blink. The aberrations were calculated from the elevations provided by corneal topography. All d...

A method for obtaining the best image plane for holographic optical elements by the use of the concept of entropy is described. This method is applied to in-line holographic lenses with different values of spherical aberration. Numerical results show that for holograms with large aberrations the best image plane (obtained by the use of the concept of entropy) is different from the minimum-aberr...

In some experiments, the levels of factors are difficult to change; then fractional factorial split-plot (FFSP) designs suitable for selection. an FFSP design, divided into two classes—the whole plot (WP) and subplot (SP) factors. selection WP can affect that SP factors, which attracts much attention Paying more a new optimality criterion selecting such is proposed. The robustness proposed meth...

In modern high-numerical-aperture (NA) optical scanning instruments, such as scanning microscopes, optical data storage systems, or laser trapping technology, the beam emerging from the high-NA objective focuses deeply through an interface between two media of different refractive index. Such a refractive index mismatch introduces an important amount of spherical aberration, which increases dyn...