Multiple-wavelength reference based on interleaved, sampled fiber Bragg gratings and molecular absorption.

We present a wavelength calibration reference based on interleaved, sampled fiber Bragg gratings stabilized to a molecular absorption line. Such a hybrid reference can provide multiple stable calibration peaks over a wide range of wavelengths. We demonstrate a wavelength reference that has at least 20 peaks suitable for use as calibration references in each of three wavelength regions: 850, 1300, and 1550 nm. We monitored the stability of a 1300-nm reflection peak and found that the standard deviation of the peak wavelength was 0.7 pm over a 70-day period.