Abstract: The invention refers to a compact multispectral scanning system comprising a primary mirror (1) and secondary mirror (2), wherein the mirrors face each other, are adapted to be rotated at the same angular speed in opposite directions, and are tilted with respect to their rotation axes. The primary mirror is concave, the secondary mirror is smaller than the primary mirror and the rotation axes of both mirrors are aligned. This arrangement makes the system more compact than prior art devices and avoids the dependency of the system on the operation frequency.