Method and Device for Measuring Optical Quality of the Human Eye and Its Crystalline Lens

2:

• The method of claim 1, further comprising:
• calculating a Strehl ratio for each probing point separately, said calculation made on signal intensity distributions in detected images of the laser spots of laser projections comprising their point spread functions in a status of a compensated defocus of the projected laser beam and of the detected images of said laser spots;
• reconstructing a map of the optical quality of the eye with the values of said optical quality in each probing point that is a function of the Strehl ratio;
• and
• calculating a total quality of the eye as a ratio of a number of probing points with a quality higher than the established threshold to the total number of the probing points.

3:

• A method for measuring an optical quality of a human eye based on laser ray tracing, comprising:
• probing the human eye sequentially in time with a linearly polarized laser beam in a set of points within the aperture of the eye;
• detecting images of laser spots on a retina with a photosensitive detector;
• processing detected signals;
• and
• reconstructing a distribution of wave front errors.

4:

• The method of claim 3, further comprising:
• calculating a defocus component from the reconstructed distribution of wave front errors;
• probing the human eye with the linearly polarized laser beam projected therein at an angle compensating for the defocus component;
• selecting an orthogonally polarized component of light coming from the human eye,
• detecting the orthogonally polarized component in a detection plane conjugated with the retina,
• measuring a shape and coordinates of a detected image of a spot of the laser projection on the retina;
• calculating a Strehl ratio in each probing point separately for the point spread function described by a measured shape of the spot image of the projected laser beam,
• reconstructing a map of the optical quality of the human eye with values of the optical quality in each probing point that is the function of the Strehl ratio, and
• calculating a total quality of the eye represented by a ratio of the number of probing points with the quality higher than an established threshold to the total number of the probing points.

5:

• A method for measuring an optical quality of a crystalline lens of an eye based on laser ray tracing, comprising:
• probing the eye sequentially in time with a laser beam in a set of points within an aperture of the eye;
• detecting images of laser spots on a retina with a photosensitive detector, processing the detected signals;
• reconstructing the distribution of the wave front errors;
• and
• calculating the modulation transfer function.

6:

• The method of claim 5, further comprising:
• calculating a defocus component from the reconstructed distribution of the wave front errors;
• probing the eye in a set of probing points over the aperture thereof with a linearly polarized laser beam projected into the eye at a first angle that is an angle compensating for a defocus component;
• selecting an orthogonally polarized component of a light coming from the eye;
• detecting said orthogonally polarized component in a detection plane conjugated with the retina;
• measuring coordinates of the detected image of a spot of a laser projection on the retina;
• probing the eye in the same set of probing points over the aperture with the linearly polarized laser beam projected in the eye at a second angle differing from the first angle by a normalization value;
• selecting the orthogonally polarized component of the light coming from the eye, detecting said orthogonally polarized component in the detection plane conjugated with the retina;
• measuring coordinates of the detected image of a spot of the laser projection on the retina;
• calculating s difference between coordinates of the detected spot images at the first angle of the probing laser beam and the second angle of the probing laser beam in the same probing points;
• reconstructing a two-dimensional distribution of the wave front difference;
• and
• calculating a ratio of an area of a surface of the two-dimensional distribution having a wave front difference lower than an established threshold of a total area of the surface of said two-dimensional distribution.

8:

• A method for measuring an optical quality of a crystalline lens of an eye, based on laser ray tracing, the method comprising:
• probing the eye sequentially in time with a laser beam in a set of points within an aperture of the eye;
• detecting images of the laser spots on a retina with a photosensitive detector;
• processing the detected signals;
• and
• reconstructing a distribution of wave front errors;
• wherein:
• a preliminary probing of the eye in parallel to an optical axis thereof is provided and a defocus component is derived from the reconstructed wave front errors;
• said laser beam is linearly polarized and is projected in the eye at an angle compensating for said defocus component;
• a first plane of detection is provided and is conjugated with a plane of a retina and a second plane of detection is conjugated with a plane inside the crystalline lens orthogonal to the optical axis;
• the light coming from the eye is detected separately for each of a first polarized component and a second polarized component, said first polarized component having a plane of polarization orthogonal to the polarization of the probing laser beam, the second polarized component being in the plane of polarization of said probing laser beam;
• in a first plane of conjugation, coordinates are measured of the spot imaged on a two-dimensionally photosensitive detector for the first polarization component, corresponding to the laser beam scattered in the retina, and the two-dimensional distribution of the wave front errors is reconstructed;
• in a second plane of conjugation, signal levels are measured of each of a first spot and a second spot imaged on the two-dimensionally photosensitive detector for the second polarization component, said first spot produced by the reflection of the laser beam from the retina and having passed through the crystalline lens in an outward direction, and said second spot being an image of a scattering trace of the outward passing laser beam in the crystalline lens;
• a two-dimensional distribution of scatter in the crystalline lens is reconstructed as a ratio of a signal level of the second spot to a signal level of the first spot, and its dimensionless index is calculated as an averaged value of said ratios;
• and
• the optical quality of the crystalline lens scaled in a dimensionless index is calculated as a degradation of a modulation transfer function of the eye without a deducted corneal component, said degradation of the modulation transfer function is referenced to said two-dimensional distribution of scatter in the crystalline lens.

12:

• The method of claim 9, wherein the coordinates of said first spot imaged in the second plane of conjugation are measured for the second polarization component, said measurements provided in an annular zone, whose internal size is restricted by a zone of Purkinje reflections;
• wave front errors are calculated with deduction of the corneal component in said annular zone, and compared with the wave front errors in said annular zone calculated from the measurements of the spot coordinates imaged in the first plane of conjugation for the first polarization component;
• and
• a differential modulation transfer function is calculated for said annular zone, and the optical quality of the crystalline lens scaled in a dimensionless index is calculated as the degradation of differential modulation transfer function, being referenced to said two-dimensional distribution of scatter in said annular zone.

14:

• A device for measurement of the optical quality of the crystalline lens of the human eye, comprising:
• a laser configured to emit a laser beam of a wavelength suitable for propagation in the human eye;
• a two-axis acousto-optical deflector on a path of the laser beam;
• a two-output generator of digitally synthesized sinusoidal voltages with its outputs electrically connected to said two-axial acousto-optical deflector and configured to control the deflection of said laser beam in both orthogonal directions;
• a collimating optical system placed at the exit of the two-axis acousto-optical deflector with its front focus in a center of beam deflection;
• a conjugating telescopic system with a lens component or a mirror component and with its optical axis coincident with an optical axis of said collimating optical system;
• a polarizing beam splitter placed between said collimating optical system and said conjugating telescopic system;
• a first photosensitive detector with a coordinate measurement function placed in the path of the laser light reflected by said polarizing beam splitter with the feature of optical conjugation with the plane of the retina;
• a second photosensitive detector with a profile measurement function is placed through a beam splitter installed between the eye and the lens component or the mirror component of said conjugating telescope system, said profile measuring photosensitive detector is optically conjugated with the plane inside the crystalline lens orthogonal to the optical axis;
• and
• a processing unit in operable communication with each of the laser, the two-output generator of digitally synthesized sinusoidal voltages, the conjugating telescopic system, and the position sensitive detection system.

15:

• A device for measurement of the optical quality of the crystalline lens of the human eye, comprising:
• a multi-laser block containing a plurality of lasers, each of said plurality configured to emit independently a laser beam of a wavelength suitable for propagation in the human eye, an optical axis of each laser in the plurality oriented to cross an optical axis of the device in a single point;
• a collimating optical system placed on the optical axis of the device with its front focus in a center of beam deflection;
• a conjugating telescopic system with a lens component or a mirror component having an optical axis coincident with an optical axis of the collimating optical system;
• a polarizing beam splitter placed between the collimating optical system and the conjugating telescopic system;
• a first photosensitive detector with a coordinate measurement function placed in a path of laser light reflected by said polarizing beam splitter with a feature of optical conjugation with a plane of a retina in the human eye;
• a second photosensitive detector with a profile measurement function is placed through a beam splitter positioned between the human eye and the lens component or the mirror component of the conjugating telescope system, the profile measuring photosensitive detector is optically conjugated with the plane inside the crystalline lens orthogonal to the optical axis;
• and
• a processing unit in operable communication with each of the plurality of lasers, a two-output generator of digitally synthesized sinusoidal voltages, the conjugating telescopic system, and a position sensitive detection system.