Lens, Shalakya Tantra
LENS Lens is a transparent, biconvex structure with rounded border (equator), the main function is to converge the light rays to form image on retina properly, anterior surface is less convex than posterior surface, it is kept in its position by suspensory ligaments or zonule which is extending form ciliary body, its position is posterior to iris and anterior to vitreous, it is made up of Lens fibres and enclosed in an elastic capsule. Lens axis deviates from visual axis by about 4°, underneath the lens capsule there is a single layer of cubical epithelium from which the lens fibres are developed and arranged concentrically around the axis like the scales of an onion. Central part of lens which is hard is known as nucleus and peripheral part which is soft is known as cortex. Axial diameter 3.5 to 4mm equatorial diameter 8 to 10 mm weight of lens approx 0.2 grams Volume of Lens approx 0.163 ml Parts : (1) Capsule (a) zonular lameliae or pericapsuiar layer to which suspensory li...