Lens manufacturing method and system, and progressive lens

A progressive lens, comprising:

• a lens substrate;
• and
• at least two micro/nano structure sets varying in optical properties, which are formed on the lens substrate through photopolymerization;
• wherein a required refractive-index distribution is realized through the at least two micro/nano structure sets arranged in a predetermined layout;
• a minimum feature size of the at least two micro/nano structure sets is 50 nanometers;
• the at least two micro/nano structure sets are formed on the lens substrate by coating photoresists varying in refractive index and photopolymerization;
• wherein each of the at least two micro/nano structure sets comprises a micropillar array and gradient microlenses;
• in a far-vision region of the lens, the micropillar array having substantially fixed height and diameter is designed, and by adjusting a material refractive index and an arrangement density of the micropillar array, a relatively stable dioptric power required in the far-vision region is achieved;
• and in a transition region and a near-vision region, the gradient microlenses are arranged, with a radius of curvature of the gradient microlenses gradually decreasing from the far-vision region to the near-vision region to achieve a smooth transition of dioptric power, and by adjusting a height and curvature of the gradient microlenses, a refraction angle of light is controlled to satisfy vision correction needs at different distances;
• wherein distribution of each of the at least two micro/nano structure sets comprises axial distribution and radial distribution;
• in the axial distribution:
• “axial” refers to a direction from a top of the lens to a bottom of the lens;
• in the far-vision region, the at least two micro/nano structure sets remain uniformly distributed;
• upon entering the transition region, sizes and arrangement densities of the at least two micro/nano structure sets vary according to a linear gradient function or an S-shaped gradient function to ensure a smooth transition of dioptric power;
• and in the near-vision region, a final distribution state of each of the at least two micro/nano structure sets is determined according to near-vision correction needs;
• in the radial distribution:
• “radial” refers to a horizontal direction with a lens center as a center;
• in a central region of the lens, the at least two micro/nano structure sets are distributed relatively densely and uniformly to ensure central vision clarity;
• toward an edge region, the distribution gradually becomes sparser, and shapes and sizes of the at least two micro/nano structure sets are slightly adjusted to compensate for aberrations caused by edge refraction;
• wherein a defocus amount De of each of the at least two micro/nano structure sets satisfies:
• +4.00 D≤De≤+10.00 D, wherein D represents diopters and +10.00 D is an extreme defocus;
• each of the gradient microlenses reaches the extreme defocus within a field angle of 8°;
• the defocus amount of each of the at least two micro/nano structure sets is positively correlated with the field angle, such that the defocus amount increases as the field angle increases, and an effective defocus amount in a micro/nano-structure region is larger.

A lens manufacturing system, comprising:

• a femtosecond laser;
• a focusing optical system;
• a three-dimensional motion stage;
• a photoresist feeding device;
• and
• a software for designing and simulating micro/nano structures;
• wherein the three-dimensional motion stage is configured to load and move a lens substrate and to drive the lens substrate to rotate;
• the photoresist feeding device is configured to coat photoresists varying in refractive index on the lens substrate;
• the femtosecond laser is configured, according to a micro/nano-structure pattern provided by the software, to perform lithography on the lens substrate after the photoresists are coated, so as to obtain at least two micro/nano structure sets varying in optical properties on the lens substrate, thereby realizing a required refractive-index distribution through the micro/nano structures;
• the focusing optical system is configured to control scanning speed and focal length of a laser beam emitted by the femtosecond laser;
• a minimum feature size of the at least two micro/nano structure sets is 50 nanometers;
• wherein each of the at least two micro/nano structure sets comprises a micropillar array and gradient microlenses;
• in a far-vision region of the lens, the micropillar array having substantially fixed height and diameter is designed, and by adjusting a material refractive index and an arrangement density of the micropillar array, a relatively stable dioptric power required in the far-vision region is achieved;
• and in a transition region and a near-vision region, the gradient microlenses are arranged, with a radius of curvature of the gradient microlenses gradually decreasing from the far-vision region to the near-vision region to achieve a smooth transition of dioptric power, and by adjusting a height and curvature of the gradient microlenses, a refraction angle of light is controlled to satisfy vision correction needs at different distances;
• wherein distribution of each of the at least two micro/nano structure sets comprises axial distribution and radial distribution;
• in the axial distribution:
• “axial” refers to a direction from a top of the lens to a bottom of the lens;
• in the far-vision region, the at least two micro/nano structure sets remain uniformly distributed;
• upon entering the transition region, sizes and arrangement densities of the at least two micro/nano structure sets vary according to a linear gradient function or an S-shaped gradient function to ensure a smooth transition of dioptric power;
• and in the near-vision region, a final distribution state of each of the at least two micro/nano structure sets is determined according to near-vision correction needs;
• in the radial distribution:
• “radial” refers to a horizontal direction with a lens center as a center;
• in a central region of the lens, the at least two micro/nano structure sets are distributed relatively densely and uniformly to ensure central vision clarity;
• toward an edge region, the distribution gradually becomes sparser, and shapes and sizes of the at least two micro/nano structure sets are slightly adjusted to compensate for aberrations caused by edge refraction;
• and
• wherein a defocus amount De of each of the at least two micro/nano structure sets satisfies:
• +4.00 D≤De≤+10.00 D, wherein D represents diopters, and +10.00 D is an extreme defocus;
• each of the gradient microlenses reaches the extreme defocus within a field angle of 8°;
• and the defocus amount of each of the at least two micro/nano structure sets is positively correlated with the field angle, such that the defocus amount increases as the field angle increases, and an effective defocus amount in a micro/nano-structure region is larger.