2 December 2013 Characteristics of an adjacent pulse repetition interval length as a scale for length
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Optical Engineering, 53(5), 051502 (2013). doi:10.1117/1.OE.53.5.051502
This paper describes the characteristics of the adjacent pulse repetition interval length (APRIL), which is used as a scale for femtosecond optical frequency comb (FOFC)-based length measurements. This approach is based on the analogy between the phase refractive index and the group refractive index. Because the former influences the wavelength, which is the basic parameter used to describe monochromatic light in terms of length measurement, we investigated the latter to analyze the theoretical properties of the APRIL when used as a length standard. The results of theoretical analyses and numerical investigations show that when the air parameters change, the changes in the wavelength of a He–Ne laser and the APRIL of an FOFC laser are of the same order of magnitude. The difference between the effects of the phase refractive index on the wavelength and the group refractive index on the APRIL was also confirmed. The proposed concept and analysis pave the way for developing a length traceability system based on the APRIL via optical fibers.
© 2014 Society of Photo-Optical Instrumentation Engineers (SPIE)
Dong Wei, Masato Aketagawa, "Characteristics of an adjacent pulse repetition interval length as a scale for length," Optical Engineering 53(5), 051502 (2 December 2013). https://doi.org/10.1117/1.OE.53.5.051502

Refractive index


Standards development

Environmental sensing

Optical fibers

Frequency combs


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