Point-Spread Function |
As shown in the surface plot above, the point-spread function of LWS is diffraction limited when observing at wavelengths beyond 8 µm under normal Mauna Kea seeing conditions. The image is of Alpha Tau at 11.7 µm and shows the high central peak and the first Airy ring of the diffraction pattern. Shift-and-add processing was performed on this image with a resulting FWHM of 0.28 arcsec. Non-shift-and-add point source images with LWS yield a typical FWHM of 0.35 arcsec.