静态角标校装置的温度稳定性分析

静态角标校装置是由若干个平行光管组成测角场，形成角度基准，用于检验大型光电经纬仪静态测角精度。由于大型光电经纬仪对静态测角精度指标要求很高，因此对作为检验基准的静态角标校装置提出很高的精度要求，要求在24 小时内角度基准的稳定精度不大于2（rms）。针对这一要求，讨论了实验室环境温度变化对角度基准的影响，影响角度基准稳定精度的因素是平行光管光轴指向，通过试验说明实验室环境温度在一定范围的变化不会影响静态角标校装置中使用的卡塞格林反射式平行光管的光轴指向。当实验室温度变化超过规定的范围时，光轴指向会发生变化，静态角标校装置的精度将不能满足要求。为实验室建设提出环境保障的明确要求，确保测量的准确性。同时通过光学设计分析软件计算结果说明:光管制造材料的不均匀性及装配间隙、应力等因素是影响光轴指向变化的主要原因。因此在光管设计时应充分考虑这些因素的影响，合理分配公差，减小装配应力，使环境温度变化对光管光轴指向的影响最小化。

Temperature stability analysis of static angle calibration devices

Static angle calibration devices are applied to detect the static angle measuring accuracy of large scale photoelectric theodolites, and the stabilization accuracy of angle datum which is affected by the optical axis orientation of autocollimator is required less than 2″ (rms) in 24 hours. According to the requirement, the impact of ambient temperature on angle datum was studied. Experiment results proved that the optical axis orientation of Cassegrain reflective collimator used in the static angle calibration devices was not influenced when the ambient temperature changed in a certain range, but the static angle calibration devices no longer met the precision requirement when the environmental temperature was beyond the range of specified operation temperature. In order to ensure the measurement accuracy, specific requirements of laboratory infrastructure were put forward. In addition, the calculation results of optical design software showed that the inhomogeneity of the collimator manufacturing material, assembly tolerance, stress were the main factors affecting the optical axis orientation.