Varied line-space plane grating and its ruling experiment

Varied line-space (VLS) plane grating is the great achievement in the history of gratings. But its fabrication is so difficult that only few countries can make it with a grating ruling engine. This paper firstly studies the focusing property of the VLS plane grating. Then a VLS plane grating is designed. The ray-tracing result shows that the grating has a good self-convergence feature. A VLS grating sample was ruled using the improved equi-space, intermittent grating ruling engine in Changchun Institute of Optics and Fine Mechanics (CIOM). The groove spacings of the grating sample were measured by using Talystep. The results show that the groove spacing is varied continuously, which gives the conclusion that the design method and the VLS control method in this paper are effective.