The term "large" has specific implications about types of optics and their uses. In this paper large optics are defined and figure, beauty, and blank characteristics are specified with tolerances for each. Because it is useless to discuss specifications for properties that cannot be measured, tests for each specification are described. The specification of a large optic takes far more thought and insight than is the case for small optics because of the high cost and demanding applications of large optics.
Robert E. Parks,
"Optical Specifications And Tolerances For Large Optics", Proc. SPIE 0406, Optical Specifications: Components and Systems, (9 December 1983); doi: 10.1117/12.935675; https://doi.org/10.1117/12.935675