Digital thin-film color optical memory

A promising optical memory device called digital thin-film (DTF) color opti cal memory is presented. The DTF optical memory utilizes localized regions of varying thickness to adjust the spectral characteristic of reflected lig ht from a broad band source. The DTF structure has been fabricated by Ga+ f ocused ion beam milling on thermally grown silicon dioxide on Si to prove t he concept. A charge-coupled device array is used as the optical detector f or the readout of the stored data. The reflected light image of the DTF mem ory reveals easily discriminated color levels and proves the suitability of using optical means to extract the stored data. DTF optical memory structu res with 16 physical levels or 4 bits/pixel have been fabricated providing an equivalent storage density in excess of 5 Gb/in.(2) (C) 2001 American In stitute of Physics.