The 4441 High-Efficiency Resonant Phase Modulator incorporates a patent-pending design to achieve twice the efficiency over our popular standard designs. This 500-900 nm, MgO:LiNbO₃ 0.5 to 2.0 GHz modulator has low insertion losses and efficient phase modulation with extremely low unwanted amplitude modulation, this new line of phase modulators is ideal for a wide variety of demanding applications. Using these modulators is easy, simply pass the beam through pre-aligned mechanical apertures for the optimal optical performance. 8-32 and M4 mounting holes.