Method for determining control information for photorefractive corneal surgery and method for providing correction information required therefor

A method of controlling laser radiation irradiated onto a cornea of an eye to be treated photorefractively, the method comprising:

• obtaining a corneal ablation profile by measuring optical properties of an eye to be treated;
• transforming the corneal ablation profile into a spatial frequency spectrum;
• correcting a phase value for each of a plurality of discrete spectral components of the corneal ablation profile on the basis of stored phase correction information, wherein the stored phase correction information comprises a predetermined relationship between a phase value of a spatial frequency and a corrected phase value of the spatial frequency for a plurality of spacial frequencies;
• transforming the spatial frequency spectrum into a geometric spatial domain to obtain a corrected ablation profile utilizing the corrected phase values for each of the plurality of discrete spectral components;
• and
• controlling a laser source producing laser radiation irradiated onto the cornea of an eye with control information formed on the basis of the corrected ablation profile.

A method of controlling laser radiation irradiated onto a cornea of an eye to be treated photorefractively, the method comprising:

• obtaining a corneal ablation profile by measuring optical properties of an eye to be treated;
• transforming the corneal ablation profile into a spatial frequency spectrum;
• correcting a real-part value of a complex valued magnitude for each of a plurality of discrete spectral components of the corneal ablation profile on the basis of stored real-part correction information, wherein the stored real-part correction information comprises a predetermined relationship between a real part-value of a spatial frequency and a corrected real-part value of the spatial frequency for a plurality of spacial frequencies;
• transforming the spatial frequency spectrum into a geometric spatial domain to obtain a corrected ablation profile utilizing the corrected real-part values for each of the plurality of discrete spectral components;
• and
• controlling a laser source producing laser radiation irradiated onto the cornea of an eye with control information formed on the basis of the corrected ablation profile.

A method of controlling laser radiation irradiated onto a cornea of an eye to be treated photorefractively, the method comprising:

• obtaining a corneal ablation profile by measuring optical properties of an eye to be treated;
• transforming the corneal ablation profile into a spatial frequency spectrum;
• correcting a imaginary-part value of a complex valued magnitude for each of a plurality of discrete spectral components of the corneal ablation profile on the basis of stored imaginary-part correction information, wherein the stored imaginary-part correction information comprises a predetermined relationship between a imaginary part-value of a spatial frequency and a corrected imaginary-part value of the spatial frequency for a plurality of spacial frequencies;
• transforming the spatial frequency spectrum into a geometric spatial domain to obtain a corrected ablation profile utilizing the corrected imaginary-part values for each of the plurality of discrete spectral components;
• and
• controlling a laser source producing laser radiation irradiated onto the cornea of an eye with control information formed on the basis of the corrected ablation profile.

An apparatus for performing laser treatment of an eye, comprising:

• a laser for providing laser radiation;
• a scanner for moving the laser radiation across a corneal surface of an eye to be treated;
• memory for storing correction information representing, in relation to each of a plurality of spatial frequencies, a predetermined relationship between values of at least one spectral parameter at the spatial frequency and corrected parameter values at the spatial frequency;
• and
• a control unit for controlling operation of the scanner based on a corrected ablation profile, wherein the control unit calculates the corrected ablation profile based on a corneal ablation profile obtained by measuring optical properties of the eye and the correction information stored in the memory by:
• transforming the corneal ablation profile into a spatial frequency spectrum;
• determining, in relation to each of various discrete spectral components of the ablation profile, a corrected value for at least one spectral parameter based on the stored correction information;
• and
• transforming the spatial frequency spectrum with the parameter-corrected spectral components into the geometric spatial domain to obtain the corrected ablation profile.

A method of laser treating an eye, comprising:

• providing correction information representing, in relation to each of a plurality of spatial frequencies that differ by at least a frequency value, a predetermined relationship between values of at least one spectral parameter for the spatial frequency and corrected parameter values for the spatial frequency;
• transforming a corneal ablation profile into a spatial frequency spectrum, the corneal ablation profile obtained by measuring optical properties of an eye to be treated;
• determining, in relation to each of various discrete spectral components of the ablation profile, a corrected value for at least one spectral parameter based on the provided correction information;
• transforming the spatial frequency spectrum with the parameter-corrected spectral components into a geometric spatial domain to obtain a corrected ablation profile;
• and
• controlling laser radiation across a corneal surface of the eye based on the corrected ablation profile.