Abstract: A visible light characteristic changing layer formed from photosensitive or heat-sensitive material is formed in a location which can be viewed from a part of a label surface of an optical disk. The optical disk is set on a turntable of an optical disk unit while the label surface of the optical disk is directed downward. The optical disk and an optical pickup are moved mutually along the plane of the optical disk. In synchronism with the relative movement, the power of a laser beam output from the optical pickup is modulated in accordance with image data, such as characters or graphic images to be printed, and the laser beam is emitted onto the visible light characteristic changing layer. As a result of the visible light characteristic changing layer being exposed to the laser beam, a visible-light reflectivity of the visible light characteristic changing layer is changed, thereby forming a image corresponding to the image data on the label surface.

Abstract: An optical disc recording system for recording data on a writable type optical disc comprises a data signal forming circuit which causes, when program information is recorded program by program separately and with interruption and table-of-contents (TOC) information is recorded later, information at a part-of-the-way or intermediate position (intermediate information) among position information necessary for producing the TOC information to be recorded, during each interruption, at a position inside of a TOC area on an optical disc and causes this intermediate information to be read out when writing of program information is resumed for later utilization for generation of the TOC information thereby to shorten time required for generation of the TOC information.