| abstract |
An writable optical data recording medium has a transparent substrate with a patterned surface on which a dye recording layer 3 is formed. Recesses 2a, 2b and lands 2c in the pattern are joined by curved surfaces 74, 78. Alternatively, projecting portions (2d, figure 11) are provided between the lands and recesses. In another embodiment, dye recording material (3, figure 1) is placed only in recesses (2a, 2b, figure 1) in the substrate (1, figure 1). A reflective layer 4 is made of a material having a lower reflectivity than silver, eg aluminium, copper or a di-carbocyanine dye dispersed vinyl resin solution. The medium can show a reflectivity of not less than 65% on reproduction and the cost of manufacture is reduced by avoiding the use of precious metals in the reflective. |