A control interface and imaging system for eyeball features measurement

Abstract

In this study, two white light LEDs were mounted on the upper and lower parts of a CCD camera. By using imaging and lighting control programs, lighting signals were transferred to a monolithic chip light control circuit, so that two white light LEDs could generate instantaneous flash within different preset time intervals. After capturing the images of two flash instants using the CCD camera, the center of the pupil is taken as the center of a circle to measure the rounded edge. The second image is captured when the brightness of the second pulsed light is equivalent to that of the first pulsed light, and the pupil size is the same as that of the first image. The iris region is searched from outside to inside by simply calculating the objective function value at discretely sampled radius and center. The captured images are classified as ‘zone of rejection’, ‘reserved zone’ and ‘merge zone’. A new interpolation method is used for merging two images to complete an image without any reflective dot, as well as a safe lighting design, and double-pulse iris imaging system.

Keywords:

• new interpolation method
• double pulses
• iris imaging

Acknowledgements

This work was sponsored by the National Science Council, Taiwan, Republic of China under Grant number NSC 96-2221-E-035-099-MY3 and the Chung-Shan Institute of Science and Technology under Grant number BV91U14P.