The present invention provides an optical information handling device in which reflectivity of the conventional reproduction-only type is lowered to 60% or less which is equal to the reflectivity of the write-once type and the rewritable type optical disks, whereby the interchangeability of the disk is realized. The information processing device of the invention can be interchangeable with a lower rank information handling device. Further, the optical disk of the credit size card are also realized. <IMAGE>
