Abstract: A holographic optical element (HOE) includes a substrate structure having rotational symmetry with respect to a rotational axis for rotatively supporting at least two holograms. A first hologram on the substrate structure in the path of a normally incident beam diffracts the beam by a first acute angle and in a first radial direction from the rotational axis to a first redirected path. A second hologram on the substrate structure in the first redirected path diffracts the beam by a different second acute angle and in an opposite second radial direction from the rotational axis to a second redirected path. As a result, the two holograms may be used to achieve a second redirected path at an angle to the rotational axis that has a size which is the difference between the size of the first angle and the size of the second angle.

Abstract: A star tracker for generating positional information for a vehicle includes a holographic telescope (150) having one or more fields of view for imaging stellar objects. The telescope includes a plurality of radiation detectors (100) and an input aperture comprised of a primary holographic optical element (HOE) (134). The primary HOE provides one or more wavefronts to one or more secondary HOEs (136), each of which applies a chromatic correction so as to correct for a chromatic aberration induced by the primary HOE. A single or multiple field of view Schmidt telescope embodiment is also disclosed having one or more aspheric corrector plate HOEs and one or more associated concave spherical reflectors.