gyration tensor

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gyration tensor

[ji′rā·shən ¦ten·sər]
(solid-state physics)
A tensor characteristic of an optically active crystal, whose product with a unit vector in the direction of propagation of a light ray gives the gyration vector.
References in periodicals archive ?
Two-step ablations attempt to correct negative asphericity on the cornea to improve near vision.
Comparison of six radiographic projections to assess femoral head/neck asphericity.
The diameter of this "breathing sphere" solute is a sensitive function of the asphericity of the excluded volume of the fused sphere solute.
Multisampling asphericity was corrected by applying either the Huynh-Feldt or Greenhouse-Geisser corrections for [epsilon]<0.
Repeated-measures analysis of variance, allowing for multisample asphericity by applying the Greenhouse-Geisser correction, was used to compare changes in profile of curves for cuff pressure versus time (SYSTAT v 16, SPSS Inc Chicago).
Solution for Best Fitting Spherical Curvature Radius and Asphericity of Off-Axis Aspherics of Optical Aspheric Surface Component
Optical side effects (haloes/glare) associated with multifocal IOL implantation are reduced in modern, diffractive designs incorporating optical features such as asphericity and apodization, and multifocal implantation is an increasingly popular choice (9).
Further clinical studies are required to decide whether customising the amount of spherical aberration correction to individual preoperative corneal asphericity is of clinical benefit in improving contrast and whether improved mesopic contrast comes at the expense of reduced near vision function.
With the addition of asphericity to the AcrySof([R]) Toric lens, which was already my lens of choice for astigmatic patients, I can now reduce spherical aberration, enhance image quality and improve functional vision for my cataract patients," said Edward Holland, M.
The Company's goal is to achieve custom ablations that optimize the asphericity and ultimate shape of the eye, so that it is not altered from its preoperative prolate shape thereby inducing certain aberrations that may lead to loss of overall quality of vision," commented Mr.
The human cornea is neither a true spherical, nor a true toric surface, but is a relatively complex aspheric surface with the degree of asphericity varying in each of the principle meridians.
Differences between groups over time for CBF, HR and MAP were compared using repeated measures analysis of variance with Greenhouse-Geisser correction for multisample asphericity (SPSS 16 Statistical analysis, SPSS Inc.