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Walker, Chanda Bartlett

Publications and source records attributed to Walker, Chanda Bartlett.

Achromatic shearing phase sensor for generating images indicative of measure(s) of alignment between segments of a segmented telescope's mirrors

An achromatic shearing phase sensor generates an image indicative of at least one measure of alignment between two segments of a segmented telescope's mirrors. An optical grating receives at least a portion of irradiance originating at the segmented telescope in the form of a collimated beam and the collimated beam into a plurality of diffraction orders. Focusing optics separate and focus the diffraction orders. Filtering optics then filter the diffraction orders to generate a resultant set of diffraction orders that are modified. Imaging optics combine portions of the resultant set of diffraction orders to generate an interference pattern that is ultimately imaged by an imager.

Stahl, H. Philip

Optical Phasing Sensor

This paper discusses the theory and early experimental results related to an optical phasing sensor created at Marshall Space Flight Center. The sensor is a combination of a Young's double slit experiment and a Hartmann sensor used to measure intersegment phase error of a segmented telescope or other optic. The techniques used are proven interferometric techniques and require simple mathematics. Speed and efficiency are goals of the device as well as measurement of the important central area of the segments. Early results are encouraging and show that it is likely that this technique is feasible in the lab and possibly in space.

Walker, Chanda Bartlett