Method and device for measuring and correcting aberrations of eye

Abstract

A device and method for measuring and correcting eye aberrations integrate wavefront sensing, wavefront aberration correction and optometric testing into one another and configure the optical paths of wavefront sensing and optometric testing as aplanatic structures, such that under optometric testing conditions both wavefront sensing and aberration correction can be performed simultaneously, and final optometric testing is conducted on wavefront aberration-corrected optometric parameters to verify if the wavefront aberration-corrected optometric parameters fall within normal visual range, thus ensuring the accuracy and high repetition of the measured optometric parameters.

1 . A device for measuring and correcting aberrations of an eye and for use with an ophthalmic apparatus for measuring and correcting optometric parameters, the device comprising: 
 a laser unit for providing parallel light for a retina of the eye;    a wavefront sensing unit for receiving and processing the light reflected by the retina so as to generate wavefront data of wavefront aberrations based on a shift of the light;    an aberration correcting unit for correcting a difference between the wavefront data based on the wavefront data;    an optometric testing unit for testing and verifying the wavefront aberration-corrected optometric parameters of the eye; and    a beam-splitting unit disposed between the laser unit, the wavefront sensing unit, the aberration correcting unit, the optometric testing unit for providing optical path structures configured in such a way that the wavefront sensing unit and the optometric testing unit form aplanatic structures.    
   
   
       2 . The device of  claim 1 , wherein the laser unit includes a laser transmitter, an attenuator and a beam expander.  
   
   
       3 . The device of  claim 2 , wherein the laser unit further includes an on-and-off controller.  
   
   
       4 . The device of  claim 1 , wherein the wavefront sensing unit includes a wavefront sensor and a beam expander.  
   
   
       5 . The device of  claim 4 , wherein the wavefront sensor includes an array of microlenses and an image sensor.  
   
   
       6 . The device of  claim 1 , wherein the aberration correcting unit is one selected from the group consisting of a trial lens, a liquid crystal phase modulator, a liquid zooming lens, a deformable mirror and a mirror set with a micro-brake.  
   
   
       7 . The device of  claim 1 , wherein the optometric testing unit includes a target and a backlight module for providing light for the target.  
   
   
       8 . The device of  claim 7 , wherein an imaging distance of the target is at least six meters away from the eye.  
   
   
       9 . The device of  claim 7 , wherein the target provides the eye with at least one degree of visual angle.  
   
   
       10 . The device of  claim 1 , wherein the optometric testing unit performs optometric parameter testing on at least one optometric parameter selected from the group consisting of visibility, degree of astigmatism and contrast.  
   
   
       11 . The device of  claim 1 , wherein the beam-splitting unit includes a plurality of beam-splitting prisms.  
   
   
       12 . The device of  claim 1 , further including a data processing unit.  
   
   
       13 . The device of  claim 12 , wherein the data processing unit calculates, compares and stores the wavefront data such that the stored wavefront data become reference data for laser ophthalmic surgery.  
   
   
       14 . A method for measuring and correcting aberrations of an eye and for use with an ophthalmic apparatus for measuring and correcting optometric parameters, the method comprising the steps of: 
 testing the optometric parameters of the eye (step S 1 );    performing wavefront measurement on the eye to generate wavefront data of wavefront aberrations (step S 2 );    correcting a difference between the wavefront data based on the wavefront data (step S 3 ); and    re-testing optometric parameters of the eye to verify if the wavefront aberration-corrected optometric parameters of the eye fall within normal visual range, and in the event of any of the wavefront aberration-corrected optometric parameters outside normal visual range, the steps S 2  to S 4  will be repeated unless and until the wavefront aberration-corrected optometric parameters fall within normal visual range (step S 4 ).    
   
   
       15 . The method of  claim 14 , wherein the testing in the steps S 1  and S 4  are performed, using an optometric testing unit.  
   
   
       16 . The method of  claim 15 , wherein the optometric testing unit includes a target and a backlight module for providing light for the target.  
   
   
       17 . The method of  claim 14 , wherein the step S 2  of performing wavefront measurement on the eye is achieved, using a laser unit in conjunction with a wavefront sensing unit.  
   
   
       18 . The method of  claim 17 , wherein the wavefront sensing unit includes a wavefront sensor and a beam expander.  
   
   
       19 . The method of  claim 18 , wherein the wavefront sensor includes an array of microlenses and an image sensor.  
   
   
       20 . The method of  claim 17 , wherein the laser unit includes a laser transmitter, an attenuator and a beam expander.  
   
   
       21 . The method of  claim 20 , wherein the laser unit further includes an on-and-off controller.  
   
   
       22 . The method of  claim 14 , wherein the step S 3  of correcting the difference between the wavefront data is performed by means of an aberration correcting unit.  
   
   
       23 . The method of  claim 22 , wherein the aberration correcting unit is one selected from the group consisting of a trial lens, a liquid crystal phase modulator, a liquid zooming lens, a deformable mirror and a mirror set with a micro-brake.  
   
   
       24 . The method of  claim 14 , wherein the steps S 2  and S 3  are repeated unless and until the difference between the wavefront data is less than a predetermined value, and the step S 4  is performed thereafter.