The theoretical and experimental demonstration of a multispectral Sagnac interferometer (MSI) is presented. The MSI was created by including two multiple-order blazed diffraction gratings in both arms of a standard polarization Sagnac interferometer (PSI). By introducing these high-order diffractive structures, unique spectral passbands can be amplitude modulated onto coincident carrier frequencies. Extraction of the modulated multispectral images, corresponding to each passband, is accomplished within the Fourier domain. This yields a unique multispectral sensor capable of imaging all the passbands in a single snapshot. First, the theoretical operating principles of a PSI are discussed to provide a context for the MSI. This is followed by the theoretical and experimental development of the MSI, which is an extension of a dispersion-compensated PSI. Indoor and outdoor testing and validation of the MSI are performed by observing vegetation, demonstrating the ability of our experimental setup to detect four distinct spectral passbands.
© 2010 Optical Society of America
Original Manuscript: January 12, 2010
Revised Manuscript: April 3, 2010
Manuscript Accepted: June 15, 2010
Published: July 15, 2010
Vol. 5, Iss. 12 Virtual Journal for Biomedical Optics
Michael W. Kudenov, Matthew E. L. Jungwirth, Eustace L. Dereniak, and Grant R. Gerhart, "White-light Sagnac interferometer for snapshot multispectral imaging," Appl. Opt. 49, 4067-4076 (2010)