. "airy disk" . . . "Diffraction" . "variation" . . . "appear to have measurable angular size" . "diffraction-limited spot" . . "diffraction of light" . "Airy disk" . "Airy unit" . "sharper" . . "Airy ring" . . "Airy patterns" . "Airy disk" . "dots or single pixels" . "Airy pattern" . "Airy function" . "Airy disc" . "Airy diffraction pattern" . "Airy diffraction" . "Airy Pattern" .