Optical Surface specifications and Tolerances

Lens and tool optical surface specifications (spherical or aspherical), are typically given in  terms of “fringes” of surface departure from an ideal surface, which also includes irregularity of the surface in “fringes”. The use of a profilometer allows for measurement of rotationally symmetric surfaces, and interference tests are utilized for spherical evaluation.


Tooling Requirements
The material used for tooling in the Precision Glass Molding process is a Carbide which allows molding at high temperature and offers a very long mold insert lifetime. The manufacturing of the required geometry of the tooling is performed by a proprietary grinding and polishing process. This method allows for minimal deviation of the optical surface with respect to  the outside diameter of the the tool. Tolerancing of the tool geometery ensures a precision fit and minimizes the tilt/decenter/wedge of the lens surfaces.

Tooling capabilities and tolerances

Surface Roughness        5-20 A RMS
Surface Accuracies        1/10  λ