Method for providing control data for an eye surgical laser of a treatment apparatus
A method for providing control data for an eye surgical laser is disclosed. A control device ascertains a lenticule geometry of a lenticule to be separated from predetermined visual disorder data of a human or animal eye. The control device ascertains a correction value for compensating for a deformation of the lenticule, which is generated by at least one contact element of the treatment apparatus. The control device ascertains a deformation geometry of the lenticule, wherein a deformation refractive power value is calculated depending on the refractive power value to be corrected and the correction value. A deformation diameter is calculated depending on a lenticule diameter and the correction value. The control device provides control data for controlling the eye surgical laser, which uses the deformation geometry for the separation of the lenticule.
1 . A method for providing control data of an eye surgical laser of a treatment apparatus for separation of a lenticule, wherein the method comprises the following steps performed by a control device:
ascertaining a lenticule geometry of the lenticule to be separated from predetermined visual disorder data of a human or animal eye, wherein the lenticule geometry is defined by means of a refractive power value to be corrected and a lenticule diameter;
ascertaining a correction value for compensating for a deformation of the lenticule, which is generated by at least one contact element of the treatment apparatus, wherein the correction value is determined by means of at least one preceding measurement of the treatment apparatus;
ascertaining a deformation geometry of the lenticule, wherein the deformation geometry is defined by means of a deformation refractive power value and a deformation diameter, wherein the deformation refractive power value is calculated depending on the refractive power value to be corrected and the correction value and the deformation diameter is calculated depending on the lenticule diameter and the correction value, wherein the deformation diameter is calculated by means of a multiplication of the lenticule diameter by a parameter depending on the correction value, wherein the parameter is determined by means of a theoretical lenticule geometry model; and
providing control data for controlling the eye surgical laser, which uses the deformation geometry for separating the lenticule.
2 . The method according to claim 1 , wherein the correction value is ascertained from a deviation of the refractive power value to be corrected and an achieved refractive power value, and wherein the achieved refractive power value is determined after an application of the treatment apparatus without use of the deformation geometry.
3 . The method according to claim 2 , wherein the correction value is statistically determined from multiple preceding measurements of the refractive power value to be corrected and the achieved refractive power value.
4 . The method according to claim 2 , wherein the achieved refractive power value is determined at least at two different points of time, wherein the correction value is ascertained from an average value of the deviations at the at least two different points of time.
5 . The method according to claim 3 , wherein the correction value is statistically determined by means of a linear regression.
6 . The method according to claim 1 , wherein a lenticule height or a lenticule volume is kept constant in the calculation of the deformation geometry, and wherein the deformation refractive power value is calculated by means of a multiplication of the refractive power value to be corrected by a reciprocal value of the correction value.
7 . The method according to claim 6 , wherein the deformation diameter is calculated by means of a multiplication of the lenticule diameter by the square root of the correction value with a lenticule height kept constant and the deformation diameter is calculated by means of a multiplication of the lenticule diameter by the fourth root of the correction value with a lenticule volume kept constant.
8 . A control device, which is configured to perform a method according to claim 1 .
9 . A treatment apparatus with at least one eye surgical laser for the separation of a lenticule of a human or animal eye by means of photodisruption and at least one control device according to claim 8 .
10 . The treatment apparatus according to claim 9 , wherein the laser is formed to emit laser pulses in a wavelength range between 300 nm and 1400 nm, at a respective pulse duration between 1 fs and 1 ns, and a repetition frequency of greater than 10 KHz.
11 . The treatment apparatus according to claim 9 , wherein the control device
comprises at least one storage device for at least temporary storage of at least one control dataset, wherein the control dataset or datasets include control data for positioning and/or focusing individual laser pulses in a cornea of the human or animal eye; and
includes at least one beam device for beam guidance and/or beam shaping and/or beam deflection and/or beam focusing of a laser beam of the laser.
12 . The treatment apparatus according to claim 10 , wherein the laser is formed to emit laser pulses in a wavelength range between 700 nm and 1200 nm, at a respective pulse duration between 10 fs and 10 ps, and a repetition frequency of between 100 kHz and 100 MHz.
13 . A non-transitory computer-readable medium storing a computer program including instructions, the instructions cause a treatment apparatus with at least one eye surgical laser for the separation of a lenticule of a human or animal eye by means of photodisruption, and at least one control device to execute the method according to claim 1 .
14 . The method according to claim 1 , wherein the parameter is determined by means of the Munnerlyn formula.
15 . The method according to claim 1 , wherein the deformation diameter is calculated by means of a multiplication of the lenticule diameter by the square root of the correction value with a lenticule height kept constant and the deformation diameter is calculated by means of a multiplication of the lenticule diameter by the fourth root of the correction value with a lenticule volume kept constant.