This work describes ocular astigmatism and factors which affect it. Further, total and corneal astigmatism are described and it is analyzed their relationship. An analysis of a diameter of a geometric circle of confusion is performed for the case of defocus and astigmatism. The formulas for modeling fundamental image characteristics of an eye are described. The paper is completed with an example of an experimental analysis of corneal and total astigmatism measured by aberrometry and an analysis of the influence of astigmatism on visual acuity. and V práci je popsána stručně problematika astigmatismu oka a faktorů, které jej ovlivňují. Je charakterizován celkový astigmatismus a tzv. rohovkový astigmatismus. Dále je provedena analýza průměru geometrického rozptylového kroužku na sítnici pro případ defokusace a astigmatismu a jsou popsány vztahy, kterými lze modelovat základní obrazové charakteristiky v důsledku aberací optické soustavy oka. Článek je doplněn příkladem experimentální analýzy astigmatismu při aberometrickém měření a vlivu astigmatismu na zrakovou ostrost.
Paper describes the origin and evolution of the India business community, which operated in Russia´s Astrakhan from the 1730s to the mid-19th century. It focuses primarily on economic activity of the merchants and its development throughout the time and the importance of Indian presence Astrakhan for the economy of the Russian Empire and its eastern expansion. Both the social and the political status of this community are treated at some length as well as its everyday life., Michal Wanner., and Obsahuje seznam literatury
A new method of positional reduction of all-sky photographs taking into account the difference of zenith and the centre of projection is presented. The importance of the exact knowledge of the exposure. time for the evaluation of meteor photographs is demonstrated.