精密光束偏离装置棱镜组件的光机热分析

以精密光束偏离装置的棱镜组件为有限元模型，进行了光机热集成分析.对棱镜组件的结构强度进行了校核，分析了机械载荷作用下的镜面变形；通过模态分析，给出了装置的动态特性和镜面面形振动幅值的变化情况；最后对棱镜的热弹性变形进行了分析，对棱镜的光学性能进行了评价.结果表明：棱镜组件的最大变形在10 nm量级，最大应力为0.403 MPa，应力和应变相对于结构的准确度要求和材料的许用应力具有较大的裕度；前后棱镜组件的固有频率都大于550 Hz，装置具有良好的动态性能；通过对比棱镜在热-结构耦合分析和机械载荷下的分析结果，说明热效应对棱镜表面变形的影响远远大于机械载荷的影响.装置使用时必须采取严格的温控措施.

Optical-mechanical-thermal Analysis on Prism Assembly of Precision Light Beam Scanner

Regarding the prism assembly of precision light beam scanner as a finite element model, the optical-mechanical-thermal integrating analysis was done. In terms of structure statics, the structure design and intensity of the prism assemble was verified and checked, and the surface deformation analysis of the prism was correspondingly provided under steady-state mechanical loading; Through the mode analysis , the dynamic characteristic of the device and the vibration amplitude change of the prism surface was obtained; then the hot elasticity distortion of the prism was analyzed and the estimation of optics performance of the prism was given. The analysis results show: the maximal distortion of the prism assembly was 10 nm magnitude and the maximal stress was 0.403 MPa, which has much tolerance to the admissible stress of material and the precision requirement of structure; The natural frequency of the front prism assembly and the back one both were greater than 550 Hz, which indicated the dynamic performance of the device very well.Through comparing thermal-structure coupling analysis with mechanical loading analysis, the influence of heat effect on the prism surface deformations was proved far greater than the influence of mechanical loading, so the strict temperature-controlled measure must be taken when the device is used.