A Low-Cost, Scriptable, Microcontroller-Based Voltage Driver for Digital Electro-Optic Modulator Polarization Control

Electro-optic modulator (EOM) polarization controllers offer precise manipulation of optical polarization states, but require multiple independent voltage sources, significantly increasing system complexity and cost. In this work, we present a low-cost, compact, scriptable voltage driver that enables six independently controlled bipolar voltage outputs derived from a single pair of fixed positive and negative voltage sources. Utilizing a Raspberry Pi Pico, serial peripheral interface (SPI)-controlled digital potentiometers, and efficient voltage regulation, our device provides the voltage control necessary for full polarization state transformation. This solution offers a cost-effective alternative to expensive commercial products, filling a gap in the market where dedicated devices for high-precision EOM control are currently lacking.