Measurement of group refractive indices of glass using a color-selective multi-pulse generated with a spatial light modulator

We demonstrate a method of measuring group refractive indices ( n g ) by using only a temporal waveform of a color-selective multi-pulse (CSMP) generated with a spatial-light-modulator-based optical pulse shaper. Each pulse of the CSMP is characterized by different spectral components. Thus, n g of a sample can be estimated by calculating the group delay of the spectrally different pulses in the CSMP after passing through the sample. As a proof-of-concept, we measured n g of a glass plate by using a CSMP. We confirmed that the measured n g values were in agreement with those derived from Sellmeier's formula with an accuracy on the order of 10 -4 .