noun (used with a singular verb)
Examples from the Web for dioptrics
He applied this geometrical and inventive genius to dioptrics, which, when treated of by him, became a new art.Letters on England|Voltaire
In dioptrics, is a geometrical solid bounded by three parallelograms, whose bases are equal triangles.The Sailor's Word-Book|William Henry Smyth
To this he turned his attention again in 1611, when he published a treatise on Dioptrics.
In the Dioptrics of Descartes, several other curious theorems are contained.
The only other optical treatise written by Kepler, was his Dioptrics, with an appendix on the use of optics in philosophy.