光学学报, 2015, 35 (9): 0916004, 网络出版: 2015-09-01
有色冰洲石晶体退色及光学性能的研究
Study on Colour Fading and Optical Properties of Iceland Crystal
材料 有色冰洲石 退色 透射比 消光比 主折射率 materials colored iceland crystal fading transmittance extinction ratio principal refractive index
摘要
为了了解有色冰洲石晶体经热处理退色后光学性能的变化,实验探索了黄色及紫色晶体的退色条件。采取同一块有色晶体分为两个部分,再将退色与未退色的两部分一起抛光制作样品,设计实验对样品的透射比、消光比和主折射率进行了测试。结果表明:黄色与紫色冰洲石晶体的退色温度分别为405 ℃和485 ℃(恒温4 h)。退色后,晶体的消光比与主折射率没有变化,深黄色、轻黄色和紫色冰洲石晶体的透射光谱向紫外都有较大的拓展,尤其是深黄色晶体,不但透射范围向紫外延伸了约130 nm,而且400~600 nm 波段内透射比有了较大的提高。由此可见,退色后有色冰洲石晶体达到了光学级晶体的光学性能。将有色冰洲石晶体进行退色利用,对于有效利用冰洲石晶体天然资源具有重要意义。
Abstract
In order to understand the optical properties of the colored iceland crystals after fading by heat treatment, the fading conditions are explored by choosing the yellow and the purple crystals. One colored crystal is divided into two parts - the faded and the colored, and the two parts are polished. The optical properties including transmittance, extinction ratio and principal refractive index are measured. The results indicate that the fading temperatures of yellow and purple iceland crystals are 405 ℃ and 485 ℃ respectively (constant temperature for 4 h). The extinction ratio and principal refractive index do not change after fading. The transmission spectra of the purple, dark yellow, light yellow crystals are extended to ultraviolet. Especially for the dark yellow crystal, the transmission range is extended to ultraviolet by about 130 nm, and the transmittance in 400~600 nm is greatly increased. After fading, the optical properties of colored iceland crystal achieve the optical performance of the natural clear crystal. Thus, the colour fading of iceland crystal has great significance for utilizing the scarce natural iceland crystals.
吴福全, 吴闻迪, 苏富芳, 史萌. 有色冰洲石晶体退色及光学性能的研究[J]. 光学学报, 2015, 35(9): 0916004. Wu Fuquan, Wu Wendi, Su Fufang, Shi Meng. Study on Colour Fading and Optical Properties of Iceland Crystal[J]. Acta Optica Sinica, 2015, 35(9): 0916004.