Abstract

The point spread function (PSF) calibrator data from the Come-On Plus instrument (COP, see Beuzit et al. 1994) were obtained on the 1st January 1994 at 8:54, 8:59 and 9:03 UT respectively for the KHJ bands as continous series of one-second exposure frames respectively 120 in the K band and 60 in the H band and of three 20-second exposure frame in the J band. Left part of Fig. 1 shows the distribution of the full width half maximum (FWHM) versus Strehl ratio (SR) for each individual exposures of the calibrator in JHK. The FWHM is rescaled by a factor λ/D (which corresponds to the diffraction limit at the wavelength λ for a telescope of diameter D), points clearly gather along a single curve.

© 1995 Optical Society of America