Characterization of local transfer defects in CCD´s using a multireversal transfer mode

In order to complement the usual measurement of average transfer inefficiency in linear CCD´s, a new experimental method is proposed which allows one to determine the origin and to localize some transfer defects along the shift register. By repeatedly shifting charge packets forward and backward, the effect of local defects in the potential profile is locally emphasized and can be simply measured and characterized. Experimental results are given as examples, showing that local fixed losses of less than 10^-3Qmaxcan be measured.