LENSES WITH BACKSIDE ASPHERIC / ATORIC SURFACE

With a highly developed, so-called free-form technology can now produce a thinner and more precise lenses with a wider vision field and of an adequate peripheral areas of any material. Modern digital technology enables the production of lenses with sophisticated surface.

The advantages of internal aspheric^[1] / atoric single-vision lens:

• All aspheric / astoric design is applied on the backside surface, concave side of the lenses. The lens is spherical on the convex side.
• The Aspheric / atoric design is optimized in both spherical power and cylindrical power. Aspheric / atoric concave surface^[2] is optimized in both meridians of spherical power and cylindrical power. The calculation for optimization is performed for each prescription.
• The Aspheric / astoric design is optimized in any lens thicknesses and in any lens material.
• All of optical aberrations are minimized.The pheripheral optical aberrations (spheres aberration, astigmatism, distortion) are minimal. The parameters for vertex distance and tilt angle are fixed,
• A wide range of construction, positive and negative powers,
• Center thickness and edge thickness of lenses are reduced

OKM AsToric lenses provide better optical effects such as aspherical lenses with aspherical outer surface. The outer surface of an aspherical lens can be optimized only "sferno" diopter, but the cylindrical lenses represent 70% of Rx output and in this case the optical effect is compromised.

OKM atoric lenses have on concave side optimal aphsferic in any meridian and therefore provide a broader and cleaner vision. Internal aspherical lens is thinner in minus values than a comparable external aspheric lens. Aspheric comes more pronounced with stronger curves.

conventional spherical lens	aspheric/astoric backend surface of lens

Reference:

[1] An aspheric lens or asphere is a lens whose surfaces have a profile that is rotationally symmetric, but is not a portion of a sphere.

[2] A lens or mirror surface which is altered slightly from a spherical surface in order to reduce aberrations.