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DOI: 10.17586/1023-5086-2018-85-09-84-90
Study on high precision corneal curvature radius measurement system
Full text «Opticheskii Zhurnal»
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Publication in Journal of Optical Technology
Guolin Huang, Zuojiang Xiao, Xuyang Zhou Study on high precision corneal curvature radius measurement system (Исследование системы высокоточного измерения радиуса кривизны роговицы) [на англ. яз.] // Оптический журнал. 2018. Т. 85. № 9. С. 84–90. http://doi.org/10.17586/1023-5086-2018-85-09-84-90
Guolin Huang, Zuojiang Xiao, Xuyang Zhou Study on high precision corneal curvature radius measurement system (Исследование системы высокоточного измерения радиуса кривизны роговицы) [in English] // Opticheskii Zhurnal. 2018. V. 85. № 9. P. 84–90. http://doi.org/10.17586/1023-5086-2018-85-09-84-90
Guolin Huang, Zuojiang Xiao, and Xuyang Zhou, "Study of a high precision corneal curvature radius measurement system," Journal of Optical Technology. 85(9), 590-595 (2018). https://doi.org/10.1364/JOT.85.000590
In order to improve the measurement efficiency and measurement accuracy of corneal curvature, a high precision corneal curvature radius measurement system was designed. Based on the principle of film reflection imaging, the measurement light source (concentric circle with light-emitting diode lights) is projected onto the cornea of the human eye, and the human eye cornea with the measurement light source marker is imaged on the photodetector by an optical imaging objective lens and processed by the image processing. Calculate the height of the measurement light source on the photodetector to the center of the cornea. Finally, use the method of least squares to find the corneal curvature radius. The system uses a double telecentric lens for the optical imaging objective lens to ensure that the optical system has a constant magnification in a certain depth of field. At the same time, low coherence interferometry technology is used to accurately measure the distance between the corneal apex and the measuring light source. The standard corneal simulated eye was tested with the designed prototype. The measurement accuracy was ±0.02 mm. The experimental results show that the high accuracy corneal curvature radius measurement system can effectively improve the accuracy of corneal curvature measurement.
high precision, low coherence interference, automatic tracking alignment,radius of curvature
OCIS codes: 260.0260, 120.0120, 080.0080
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