Human eye of the size of the pupil, regulation and suppression of the hormone melatonin and entrainment of the body clock. The eye is not shaped like a perfect sphere, rather it is a fused two-piece unit, composed of the anterior segment and the posterior segment. The anterior segment is made up of the cornea, iris and lens. The cornea is transparent and more curved, and is linked to the larger posterior segment, composed of the vitreous, retina, choroid and the outer white shell called the sclera. The cornea is typically about 11.5 mm (0.3 in) in diameter, and 1/2 mm (500
Eye vein verification Reza Derakhshani at University of Missouri, Kansas City, developed the concept of using the veins in the whites of the eyes for identification. He holds several patents on the technology, including a 2008 patent for the concept of using the blood vessels seen in the whites of the eye as a unique identifier. More recent research has explored using vein patterns in both the iris and the sclera for recognition. Eye vein verification, like other methods of biometric authentication, can be used in a range of security situations, including mobile banking, government security, and in healthcare environments. EyeVerify, a Kansas