Catoptrics, which treats of the reflection of light, and dioptrics, which treats of its refraction.
He applied this geometrical and inventive genius to dioptrics, which, when treated of by him, became a new art.
In dioptrics, is a geometrical solid bounded by three parallelograms, whose bases are equal triangles.
The only other optical treatise written by Kepler, was his dioptrics, with an appendix on the use of optics in philosophy.
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.
dioptrics di·op·trics (dī-ŏp'trĭks)
The branch of optics that deals with the refraction of light.