dioptrics

Catoptrics, which treats of the reflection of light, and Dioptrics, which treats of its refraction.

In the Dioptrics of Descartes, several other curious theorems are contained.

To this he turned his attention again in 1611, when he published a treatise on Dioptrics.

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.