NOVEL CONCEPT FOR NONDESTRUCTIVE READOUT METHOD FOR PHOTOCHROMIC REWRITEABLE MEMORY DEVICES

A new concept for a non-destructive readout method for a photochromic rewriteable device is proposed based on a solvatochromic dye-linked ph otochromic dye system. From the theoretical molecular orbital calculat ions for the model compound, it was shown that the W-Vis absorption ba nd of the solvatochromic dye unit is sensitive to the conformation of the nearby photochromic unit. These calculations indicate that light c orresponding to the W-Vis absorption band of the solvatochromic dye un it can be used as the non-destructive readout light, since light in th is region is found inactive to irradiation for achieving the photochro mic reaction of the photochromic dye unit. (C) 1997 Elsevier Science B .V.