Patent ID: 7106457

Claim:
An achromatic shearing phase sensor for generating an image indicative of at least one measure of alignment between two segments of a segmented telescope's mirrors, said sensor comprising: an optical grating, positioned in a first plane that is located at one of (i) approximately a pupil plane of a segmented telescope or (ii) approximately conjugate to the pupil plane of the segmented telescope, for receiving at least a portion of irradiance originating at the segmented telescope and incident on said optical grating in the form of a collimated beam, said optical grating splitting said collimated beam into a plurality of diffraction orders thereof; focusing optics, positioned to receive said plurality of diffraction orders of said collimated beam, for separating and focusing said plurality of diffraction orders of said collimated beam on a second plane; filtering optics, positioned in said second plane, for filtering said plurality of diffraction orders of said collimated beam to generate a resultant set of diffraction orders that are modified relative to said plurality of diffraction orders; imaging optics, positioned to receive said resultant set of diffraction orders, for combining portions of said resultant set of diffraction orders to generate an interference pattern in a third plane that is approximately conjugate to said first plane; and imaging means, positioned in said third plane, for generating an image of said interference pattern.