Point diffraction interference system for the optical element evaluation of the extreme wavelength in the next generation

用于下一代极端波长光学元件评估的点衍射干涉系统

基本信息

批准号：
11650048
负责人：
KAKUNAI Satoshi
金额：
$ 2.37万
依托单位：
Himeji Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

项目摘要

Recently, the technological innovation using the extreme ultraviolet wavelength with high brightness of synchrotron radiation is actively advanced.In order to effectively utilize such light, it is important to develop the technology that produces and evaluates the optical element with surface accuracy over the 2 digits compared to conventional visible light. In the conventional interferometer, the aberration between the test surface and the standard reference surface is measured. Therefore the accuracy of standard surface determines the measurement accuracy. To achieve the absolute measurement accuracy, it is necessary to develop a new interferometer that has inherent very high accuracy The point diffraction interferometer is based on diffraction, which permits the generation of a perfect spherical wavefront over a specific numerical aperture by using a circular aperture with a radius comparable to the wavelength of light. Reading accuracy of the interference fringe is remarkably improved by the fringe scanning.This report describes the point diffraction interference system, which consisted of single-mode optical fiber and the fringe scanning using the laser source of visible light. The following conclusions can be drawn.(1) A perfect spherical wavefront from the single mode optical fiber was obtained.(2) By using optical fiber, the optical system with many degrees of freedom with small detecting element was constructed.(3) Reading accuracy of the interference fringe was improved by the fringe scanning.(4) The aberration from perfect spherical surface of a commercial spherical mirror was measured at the accuracy of the number nm.

最近，利用同步加速器辐射的高亮度极紫外波长的技术创新正在积极推进。为了有效地利用这种光，开发生产和评估表面精度超过两位数的光学元件的技术非常重要。到传统的可见光。在传统干涉仪中，测量测试表面和标准参考表面之间的像差。因此标准面的精度决定了测量的精度。为了达到绝对的测量精度，有必要开发一种具有固有高精度的新型干涉仪。点衍射干涉仪基于衍射，它允许通过使用带有与光的波长相当的半径。通过条纹扫描，干涉条纹的读取精度显着提高。该报告描述了由单模光纤和可见光激光源进行条纹扫描组成的点衍射干涉系统。得出以下结论：(1)从单模光纤中获得了完美的球面波前。(2)利用光纤构建了小型检测元件的多自由度光学系统。(3)读取通过条纹扫描提高了干涉条纹的精度。(4)以纳米级精度测量了商用球面镜的完美球面像差。