We propose one- and two-wavelength methods of absolute measurement of diffraction-grating spacings based on the Littman configuration for autocollimation. The one-wavelength method has been applied to measure the spacing of a grating with a nominal value of 2160grooves/mm . The grating spacing was measured to be 463.16 nm, with an experimental standard deviation of 0.24 nm. It has been demonstrated that the both methods can provide direct traceability in the submicrometer region in terms of wavelength standards for applications in the field of nanometrology.
© 1999 Optical Society of America
(050.1950) Diffraction and gratings : Diffraction gratings
(120.3930) Instrumentation, measurement, and metrology : Metrological instrumentation
(230.1950) Optical devices : Diffraction gratings
Tai Hyun Yoon, Cheon Il Eom, Myung Sai Chung, and Hong Jin Kong, "Diffractometric methods for absolute measurement of diffraction-grating spacings," Opt. Lett. 24, 107-109 (1999)