A mirror plate (100) for a Fabry-Perot interferometer (300) includes a substrate (50), which includes silicon (Si), a semi-transparent reflective coating (110) implemented on the substrate (50), a de-coupling structure (DC1) formed on the substrate (50), a first sensor electrode (G1a) formed on top of the de-coupling structure (DC1), and a second sensor electrode (G1b), wherein the de-coupling structure (DC1) includes an electrically insulating layer (60a), and a first stabilizing electrode (G0a), which is located between the first sensor electrode (G1a) and the substrate (50).