Abstract

A series of "monochromatic" images of extended sources obtained with a wavelength tunable filter at different points along the profile of a strong Fraunhofer line provide data that occupy a threedimensional volume of two spatial and one spectral dimension. These data can be used to retrieve the line profile at any desired point on the acquired image, with a spectral resolving power that can be made comparable with that of a moderate resolution spectrograph (λ/Δλ≲25000), according to the trade-off between the spectral and the time resolution that, together with the constraints on the total amount of data, fixed the maximum number of images available along the line profile.

© 1983 Optical Society of America