Described herein is an integrated Faraday modulator and Faraday compensator (IFMC) system. Further described are methods of making an IFMC system, methods of customizing an IFMC system for a specific application, and methods of optimizing an IFMC system for a specific application. Further described is a robust 3D Finite Element Model (FEM) for designing and optimizing an IFMC system. Further described are optical instruments comprising an integrated Faraday modulator and Faraday compensator requiring only one optical crystal.