Auto-ophthalmometer of Eye Based on Image Processing

An auto-ophthalmometer based on optical imaging was developed and tested.The principles for detection and operation of the system were presented.Infrared image circle reflected from retina was received by CCD.At first,local edge detection was performed to get the threshold for the binaryzation of the whole image.Then,the edge was extracted and the diopter parameter of the retina was calculated through least squares fitting.The experiments on simulation eyes and human eyes showed that the precision of the measurement could reach ± 0.02 mm with time consuming less than 1 s.The system is feasible and can improve the measurement accuracy of the diopter parameter.