摘要:
An optical recording method and recording apparatus using this method is described in which an optimum write power of a radiation beam in the apparatus is set by writing a series of test patterns on an optical recordable medium, forming a read signal from the patterns, reading a preset value of the derivative of the modulation of the read signal with respect to the write power from the medium, and processing the read signal together with the preset value to derive an optimum value of the write power.
摘要:
An inscribable record carrier (1) is described, which comprises a previously recorded servo-track structure provided with a recording layer. The contrast between the servo-tracks (3) provided with information areas and the intermediate tracks (5) is increased by combining wide tracks (20) with a white-writing recording layer (24) or by combining narrow servo-tracks (20) with a black-writing recording layer (21).
摘要:
Information carrier and recording device for recording an information carrier. The information carrier according to the invention is of an optically inscribable type, such as a CD-E or CD-WO. Information can be recorded as a track of patterns on the information carrier. The manufacturer has provided the information carrier with carrier information, for example, information about the write power to be used. It is desirable for the patterns to have constant dimensions, irrespective of the velocity at which they are recorded. The recording process in which for the recording is effected is therefore to be adapted to the recording velocity. In order to attune this adaptation to the information carrier, the latter contains velocity-related information indicative of the recording process related to a recording velocity, for example, a reference velocity (V1-V3), while the remaining recording parameters (W1-W3) are given for a minimum and/or maximum recording velocity at which the information carrier can be recorded. The device reads the velocity-related information from the information carrier and adapts the recording process to the recording velocity that must actually be used.
摘要:
An inscribable record carrier (1) is described, which comprises a previously recorded servo-track structure provided with a recording layer. The contrast between the servo-tracks (3) provided with information areas and the intermediate tracks (5) is increased by combining wide tracks (20) with a white-writing recording layer (24) or by combining narrow servo-tracks (20) with a black-writing recording layer (21). (FIGS. 6, 7)
摘要:
A method of digitally recording information on a suitable medium, particularly a CD is described, in which method a recording is made during a recording session. The recording includes a program portion with the information to be recorded. Prior to recording the program portion, a predetermined number of run-in blocks is recorded, and subsequent to recording the program portion, a predetermined number of run-out blocks is recorded. During the recording session, an identification code identifying the recording apparatus used for the relevant recording session is recorded on the medium. The identification code is recorded in at least one of the run-in blocks and run-out blocks. This provides the possibility of recording a full identification code, even in the case of relatively short recordings.
摘要:
An optical record carrier having an information recording track which is inscribed with control data indicative of the change in average level of read-out signals from recorded and unrecorded portions of the track. Read apparatus for such record carrier scans the track with a radiation beam and derives a read-out electrical signal therefrom. The apparatus includes a signal-processing circuit which is adjusted for operation at the average level of signals derived from recorded portions of the track, such average level being determined by a programmable control unit from the recorded control data and the measured average level of signals from unrecorded portions of the track. Tracking of the scanning beam is also controlled in conformity with the difference in average signal strength from recorded and unrecorded portions of the track.
摘要:
Method of deriving a quality signal for a binary read signal having bit cells of constant length, and reading and recording devices which employ that method. During a reading process, an information pattern of optically detectable effects, representing certain of the bit cells, is scanned. A read signal is generated therefrom in which first read signal portions that exceed a reference value correspond to the effects. The quality signal is derived (in an analysis circuit) from the first read signal portions based on a measure of the deviation of first read signal portions corresponding to a particular length or mutual differences between length deviation of first read signal portions of different lengths. The quality signal can be used for adapting a recording strategy used in the recording of information, or for setting an equalizing filter. In the latter, in dependence on the quality signal, the ratio of the filter is set between a gain factor in a certain frequency range in the frequency band of the filter and a gain factor outside that frequency range.