The manufacture of a conventional spherical lens typically begins with the generation of the optic's rough shape by grinding a glass blank.
The mixture of abrasive is called slurry and it is typically made from cerium or zirconium oxide in water with lubricants added to facilitate pitch tool movement without sticking to the lens.
Precision lenses for use in applications such as lasers, interferometers, and holography have surfaces with a tenth of a wavelength (λ/10) tolerance or better.
Unconventional techniques include single-point diamond turning (SPDT) and magnetorheological finishing (MRF).
[4] To reduce the amount of surface roughness and subsurface damage, additional grinding at a smaller grit size can be done.
[6] There are various materials that can be used for optical components, including various types of glass, fused silica, silicon, and crystal quartz.
[7] The specifications for optical components vary based on their type: Specifications for prisms include pyramidal error, beam path, beam displacement and deviation, base angle, roof edge chips, wavefront, and polarization.
[8] Specifications for aspheric lenses include base radius with tolerance, conic and polynomial coefficients, best-fit sphere reference, sag table reference, sag error tolerance, slope errors versus bandwidth, wavefront per specified test, tilt, and decenter.
[8] Optical coating specifications include apertures, reflection, transmission, absorption, phase shift, adhesion, abrasion resistance, and damage threshold.
[11] All three of these military standards lack specifications for statistical surface parameters, such as root-mean-square roughness, slope error, and ripple.