Comparative on dynamic performance of double-moving mirror translational interferometer and double-moving arm rotary interferometer

Although both double-moving-mirror translation interferometers and double-arm rotary interferometers can effectively mitigate the influence of mirror tilt, existing studies have failed to clarify their differential characteristics, leading to frequent performance misjudgment and selection errors in high-precision scenarios. This study reveals the differences between the two configurations through comparative analysis. Two functionally and dimensionally analogous interferometers were designed, and the size of translation interferometer was 443.546 mm×243.773 mm, while that of rotary interferometer was 387.546 mm×300 mm. The interference ranges under mirror tilt conditions were simulated. Results indicate that the tilt angle of the moving mirror in the translation interferometer negatively correlates with the modulation depth. In contrast, the rotary interferometer can compensate for modulation depth reduction by extending reflector dimensions. Critical installation error thresholds were derived. For the translation interferometer, the permissible moving mirror tilt angle was \leqslant 0.39'' and installation error angle was \leqslant 0.1'', while for the rotary interferometer, these values were \leqslant 0.23'' and \leqslant 0.066'', respectively. The quantified differences could provide direct criteria for selecting interferometer configurations in diverse environments, effectively mitigating the performance loss risks caused by traditional experience-driven design paradigms.