Method, system and computer-program for estimating refraction of an eye of an individual

A system for estimating refraction of an eye of an individual, the system being adapted to communicate with a mobile device or with a remote computer, the system comprising:

• an image capturing device and a plurality of M light sources, where M is an integer higher than or equal to two, the plurality of M light sources being arranged eccentrically around the image capturing device at determined positions along at least two directions transverse to an optical axis of the image capturing device,
• the system being adapted and configured to illuminate the eye with a light pulse using each light source of the plurality of M light sources, and
• the image capturing device being configured to record a set of N acquired eccentric photorefraction images of the eye, where N is an integer lower than or equal to M, each image of the set of N acquired eccentric photorefraction images representing the eye illuminated by the light pulse of at least one light source of the plurality of M light sources;
• and
• a calculation module comprising a memory and a processor arranged to execute a program instructions stored in the memory to:
• k) initialize values for a set of parameters including at least sphere;
• l) Generate a set of N simulated eccentric photorefraction images using a simulation model based on the values of the set of parameters;
• m) calculate an estimator of a difference between the set of N acquired eccentric photorefraction images and the set of N simulated eccentric photorefraction images;
• n) use a minimization algorithm so as to minimize said estimator by adjusting values for the set of parameters and iterating steps 1) and m);
• and
• o) deduce an estimation of at least one refraction parameter of the eye from the adjusted values for the set of parameters.

A non-transitory computer-readable storage medium including one or more stored sequences of instructions that are accessible to a processor, and which, when executed by the processor, causes the processor to carry out at least the following steps to:

• p) provide a set of N acquired eccentric photorefraction images, wherein each image of the set of N acquired eccentric photorefraction images represents an eye illuminated by a light pulse of at least one light source of a plurality of M light sources arranged eccentrically around an image capturing device at determined positions along at least two directions transverse to an optical axis of the image capturing device, where M is an integer higher than or equal to two, and N is an integer lower than or equal to M;
• q) initialize values for a set of parameters including at least sphere;
• r) generate a set of N simulated eccentric photorefraction images using a simulation model based on the values of the set of parameters;
• s) determine an estimator of a difference between the set of N acquired eccentric photorefraction images and the set of N simulated eccentric photorefraction images;
• t) use an optimization algorithm so as to optimize said estimator by adjusting values for the set of parameters and iterating steps r) and s);
• and
• u) deduce an estimation of at least one refraction parameter of the eye from the adjusted values for the set of parameters.