Device and method for measuring corneal curvature

Abstract

The invention relates to a device for measuring corneal curvature. The device for measuring the corneal curvature comprises a double ring measurement light source, an image acquisition system and an image process and control system. The double ring measurement light source comprises an inner ring point light source and an outer ring measurement light source, wherein the inner ring point light source emits point-shaped focus light spots to the cornea of an eye, and the outer ring measurement light source emits ring-shaped measurement light to the cornea of the eye. The image acquisition system collects and detects the point-shaped focus light spot image and ring-shaped image reflected by the cornea. The image process and control system obtains the gray level change rate K of different point-shaped light spots of the point-shaped focus light spot image detected by the image acquisition system, confirms whether the detected eye is measured within an allowable range, compensates the ring-shaped image and guides the compensation direction if the eye is not measured within the allowable range and computes the corneal curvature of the detected eye according to the radius R of the compensated ring-shaped image. The invention further provides a method for measuring the corneal curvature with the device. The method for measuring the corneal curvature is simple, and an operator can find the best measurement position quickly as long as the operator follows the guide of an instrument output device.

Description

technical field The present invention relates to a device and method for measuring corneal curvature, and more specifically to such a device and method for measuring corneal curvature, which judges the measurement position of the eye to be measured based on the three-dimensional gray scale change of the image, and can judge the measurement position of the eye according to the image The image features displayed by the output device provide direction guidance, which is convenient for quickly and accurately finding the best measurement position, and realizes automatic measurement of corneal curvature. Background technique The keratometer is used to measure the curvature of the front surface of the cornea. The measurement principle is to place an object of a specific size at a specific position in front of the cornea. The object will produce an upright virtual image after being reflected by the front surface of the cornea. Just measure the size of this image. Calculate the radi...

AI Technical Summary

Problems solved by technology

The main problems existing in the current corneal curvature measurement device are: first, the optometrist needs to judge the measurement position of the eye to be tested according to the image displayed by the image output device, and the accuracy of the corneal curvature measurement depends on the operating skills of the operator; Measuring device, such as a device and method for measuring corneal curvature disclosed in CN101732030B, it is based on the change of the two-dimensional coordinates of the collected image to judge whether the focus error is within the allowable range of the error, if not, it can be compensated, However, it is not possible to give guidance on the direction of the operator based on the image, resulting in the inability to quickly find the best measurement position

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