<Ul> <Li> Measurement accuracy can be affected by a disease such as cataracts </Li> <Li> Measurement accuracy can also be affected by severe astigmatism </Li> <Li> Scanning procedure is perceived by some as invasive </Li> <Li> Not very user friendly </Li> <Li> Subject being scanned must be very close to the camera optics </Li> <Li> High equipment cost </Li> <Li> Leads to eye problems that can be identified by CT Scan . </Li> <Li> Cheap equipment used can damage your eyes on regular usage . </Li> </Ul> <Li> Measurement accuracy can be affected by a disease such as cataracts </Li> <Li> Measurement accuracy can also be affected by severe astigmatism </Li> <Li> Scanning procedure is perceived by some as invasive </Li>

The camera in an iris recognition system scans patterns of blood vessels in the back of the retina