Aspherical optics

An aspheric lens is a lens whose surfaces profile is neither a portion of a sphere nor of a circular cylinder. Since it is not spherical, the conventional production processes no longer apply to making aspheric surfaces. The production of such elements requires a high-end level of production expertise and technology.

The main advantage of aspherical lenses is that they can better correct optical aberrations compared to spherical lenses.

Only one aspherical lens is needed for the correction of optical defects, often times with even better results than a combination of more spherical lenses. This technological approach results in smaller diameters, smaller number of optical elements and lighter weights of final systems.

Measuring aspheres

We are using Taylor Hobson measuring machines as contact profilometer for measuring unpolished surfaces. Luphoscan for non-contact measurement for measuring polished surfaces.

Precision milling and polishing are executed on quality machines from German manufacturers.
If necessary, we use in-house technology MRF for the accuracy corrections of the surface shapes.

Meopta enlarged it's manufacturing capabilities and invested in technologies and machines for manufacturing and testing aspherical optics and is ready to provide design and production solutions depending on customer needs.

Production parameters  

Aspherical Standard Precision
Material All glass type Germanium, CaF2
Diameter 10-150 mm 10-250 mm
Center thickness tolerance +/- 0,1 +/- 0,05
Surface micro-roughness (Rq) 2 nm >= 2Å
Surface quality (scratch - dig) 40-20 20-10
Ashphere figure error (P-V) +/- 10 fringes +/-3 fringes
Centration - tilt 5 arc min 2 arc min
Centering - lateral displacement 0,05 mm 0,02 mm