Design Of Iris Image Acquisition System

Iris is the colorful area of one’s eyes, commonly referred to as the black eye. Irisdiagnosis is a technology based on the form which concludes human body health throughthe changes of eyes. Doctors gradually groped a set of rules according to clinicalobservation and the relationship between changes of iris and physical health, thenresearched and developed together to form a clinical technology. Iris diagnosis can beused to guide doctors to know the disease and patients from a new point of view. Now itis mainly used in the diagnosis of sub-health. This technology helps people detectingdiseases early, especially getting regulate in the sub-health state.In order to observe the situation of iris clearly and conveniently, the research of irisimage acquisition technology has been performed all the time. A good iris imageacquisition system can greatly improve the accuracy of iris diagnosis, providing greatconvenience for doctors to observe the iris features.This topic designs a contact iris image acquisition device applied to medicaldiagnosis, with optical system and data transmission circuit. The lighting device uses twocontrollable LED lights combined with lens hood to avoid the external disturbance andfaculae interference. The low intensity of light source can effectively reduce users’discomfort due to high intensity. CMOS image sensor OV7725and USB interface chipCY7C68013A perform an image data transmission. After digital processing, images datagathered by the sensor was uploaded to the host in the form of bulk transmission throughthe Universal Serial Bus, The USB interface chip can make a high transmission speedowing to the unique "quantum FIFO structure" internally. The PC program was writtenby VC++, with the functions of displaying, taking pictures and storing images. Thesystem takes color VGA images and plays on the upper computer at the speed of30fps.The iris system meets the requirements of image quality and speed for medical diagnosis,provideing the characteristics of no stimulation, small volume and low cost.