  Fringes often appear in a CCD frame, especially when a thin CCD chip and a R
or I filter is used. 88 CCD frames of the two open clusters NGC 2324 and NGC
1664 with a Johnson I filter taken from the 2.4-m telescope at Yunnan
Observatory are used to study the fringes' impacts to the astrometry and
photometry of stars. A novel technique proposed by Snodgrass & Carry is applied
to remove the fringes in each CCD frame. And an appraisal of this technique is
performed to estimate fringes' effects on astrometry and photometry of stars.
Our results show that the astrometric and photometric precisions of stars can
be improved effectively after the removal of fringes, especially for faint
stars.
