Conoptics amplitude modulators consist of an electro-optic modulator which includes an output polarizer. Internally the crystals are aligned along their x-axis. If the input polarization is oriented at 45° to the crystal axes, the applied voltage will produce a variable phase delay between the ordinary and extraordinary field components, simulating a voltage-tunable wave-plate. The modulation of the intensity is a sin2 function. Conoptics modulators allow for either vertical or horizontal input polarization.

Conoptics offers amplitude modulators for wavelengths from 192nm out to 2microns.