论文信息 - Surface figure changes due to thermal cycling hysteresis.

Surface figure changes due to thermal cycling hysteresis.

How does thermal cycling hysteresis affect surface figure in low expansivity mirror substrates? Zerodur, ULE, and Cer-Vit 20.3-cm (8-in.) diam mirrors and dilatometer samples were thermally cycled at 6 and 60 K/h with uniform and nonuniform heating. Figure distortions as large as lambda/10 were observed only with nonuniform heating of standard Zerodur, which was the only material exhibiting thermal hysteresis. A new experimental Zerodur appears to be free of this problem.

[1] W. Pannhorst,et al. Thermal expansion and length stability of Zerodur in dependence on temperature and time. , 1985, Applied optics.

[2] H. E. Bennett,et al. Effect of thermal cycling on dimensional stability of Zerodur and ULE. , 1984, Applied optics.

[3] S. Jacobs,et al. Expansion hysteresis upon thermal cycling of Zerodur. , 1984, Applied optics.

[4] S. Jacobs,et al. Thermal expansion uniformity of materials for large telescope mirrors. , 1984, Applied optics.