Eng R S, Leib K G
Appl Opt. 1969 Oct 1;8(10):2117-20. doi: 10.1364/AO.8.002117.
The anomalies that crystalline plates introduce in the quality of an image have been known for many years. With its ability to control the polarization of its output, the laser makes reexamination of these anomalies practical. Using a birefringent lens, we have produced spatially separated multiple images. Dual focal points were achieved through polarization control by utilizing the ordinary and extraordinary beams in a thin crystalline lens. Further considerations indicate the possibility of achieving F = 2(n) focal points through electrooptic control, where n is the number of thin, birefringent lenses.
晶体片在图像质量方面所引入的异常情况已为人所知多年。凭借其控制输出偏振的能力，激光使得对这些异常情况进行重新审视变得切实可行。通过使用双折射透镜，我们产生了空间上分离的多个图像。利用薄晶体透镜中的寻常光束和非寻常光束，通过偏振控制实现了双焦点。进一步的思考表明，通过电光控制有可能实现F = 2(n)个焦点，其中n是薄双折射透镜的数量。
