Abstract: An information recording and reproducing apparatus employs a magneto-optical disk including a main information recording area wherein plural pieces of main information can be recorded and a TOC area wherein control information related to each piece of main information can be recorded. When a reproducing operation cannot be performed from the TOC area, it is checked whether or not any pieces of control information exist, for example, by detecting an amplitude of a reproduced signal. Or, whether or not a recording or reproducing function of the apparatus works properly may be checked by, for example, a method of test writing and reproduction. As a result, whether or not the magneto-optical disk is a blank disk can be accurately determined. Further, when the disk is determined to be a blank disk, distinctive information indicating a blank disk is recorded in a predetermined portion of the TOC area. Thereafter, upon loading the disk, the disk is promptly determined to be a blank disk.

Abstract: An information recording and reproducing device has a first recording clock generation circuit which generates a clock based on pre-recorded information on a magneto-optical disk, a second recording clock generation circuit and a switching circuit The switching circuit selects a first recording clock when recording information is of discrete information and selects a second recording clock when recording information is of successive information. Moreover, in the present device, a first reading clock is used as well as a second clock as a clock for reading out the reproduced data from the magneto-optical disk, which had been once stored in memory. The second reading clock having a reference frequency is generated by a second clock generation circuit and is used for reading out successive information such as music information.

Abstract: An optical disk recording/reproducing device for recording or reproducing information on or from an optical disk while rotatively driving the optical disk at a constant angular velocity. The disk has pre-recorded information cyclically formed along a track so as to provide rotation control at a constant linear velocity. The device, which includes a clock generating circuit for generating a clock signal for recording or reproducing in accordance with a recording frequency of the pre-recorded information derived from signals reproduced by an optical head, is designed to perform recording or reproducing operations with a recording frequency according to the clock signal. The device further includes a magnetic filed control circuit and a recording light power control circuit whereby a magnetic field and light power to be applied to the optical disk is varied according to the recording frequency during recording operations.

Abstract: In a recording/reproducing device in accordance with the present invention, recording or reproducing positions are recognized by using absolute address parts which are predeterminately formed in a rewritable recording medium. Moreover, the device is composed so that the user can easily edit reproducing procedures stored in memory means with respect to each information in the recording medium by using the recording or reproducing positions read from above-mentioned absolute address parts and he/she can also rewrite above-mentioned reproducing procedures edited by him/her in the lead-in region of the above-mentioned recording medium.

Abstract: A recording/reproducing device performs the recording/reproduction on a recording medium having an information recording area and a table of contents area. The recording medium is provided with guiding grooves that snake in cycles corresponding to values of absolute addresses. The device divides the information recording area into a plurality of domains. Each domain corresponds to a single sampling frequency with respect to the information being recorded. An electromagnet and an optical head record information in the domain that corresponds to its sampling frequency and records additional information concerning the division in the table of contents. A spindle motor drives the disk which is adjusted such that the velocity of the disk is changed for each domain during recording and reproduction. A demodulator obtains the absolute addresses through demodulation by comparing frequencies determined from the snaking cycles of the guiding grooves with a reference frequency.

Abstract: An optical memory device for recording, reproducing, or erasing information applies an optical beam such as a laser beam onto a recording medium. The optical memory device includes a recorded region detecting circuit for detecting information recorded region formed in the recording medium. In the optical memory device, a timing control for recording, reproducing, or erasing is performed with the use of a result obtained through detection of a synchronizing signal, such as a sector mark, indicative of a starting point of an information block and another result obtained through detection in the recorded region detecting circuit. The recorded region detecting circuit includes either at least one peak hold circuit for detecting a peak level of the playback signal or a low pass filter for smoothing the playback signal, and a comparator for comparing an output obtained through the peak hold circuit or through the low pass filter with a reference voltage.

Abstract: An optical disk recording/reproducing device in accordance with the present invention has a controller that, during recording, performs the rotation control of the optical disk in Constant Linear Velocity according to reproduced signals of pre-recorded information that was pre-recorded on the optical disk, during reproduction, performs the rotation control according to reproduced signals of recorded information, and when the rotation control based on the reproduced signals of the recorded information is infeasible, switches the rotation control and performs the rotation control based on the reproduced signals of the pre-recorded information during reproduction also. As a result, a suitable and appropriate CLV control may be executed during recording and during reproduction.

Abstract: An optical card recording and reproducing device including an optical head for emitting a light beam spot to the optical card having a plurality of parallel data tracks to which data is recorded; a transfer system for transferring the optical card and/or the optical head; and a track number confirmation means for confirming the track number recorded in the address data area in the data track of the optical card. The optical card recording and reproducing device also includes a transfer stopping means for stopping the optical head when an incorrect track number is deleted. The system minimizes the relative transfer distance between the optical card and the optical head, and at the same time, the total relative transfer distance of the optical card and/or the optical head when confirming the track number more than twice. Thus, the total time required for track number confirmation can be greatly shortened.

Abstract: A recording and reproducing device providing control data recording area on erasable type optical recording medium wherein control data are recorded thereof, characterized in that there is provided a control data recording area forming device for forming control data recording areas having more than two control recording blocks which in turn have more than one recording unit. The control data can be recorded independently. A control data updating device records new control data in the control data recording blocks which were the ones not previously being updated with control data, thereby allowing this device to minimize damage caused by electrical power failure.

Abstract: An apparatus for recording and reproducing information on and from an optical disk includes a first control for producing a first control signal for controlling the rotational speed of a rotational driving apparatus, on the basis of the detected radial position; a judging apparatus which judges whether or not the reproduced signals are reproduced from a recorded region of the optical disk; a second control for producing a second control signal for controlling the rotational speed of the rotational driving apparatus, on the basis of the signals reproduced from the disk; and a switch apparatus which switches the circuit so that the rotational driving apparatus is controlled by the first control signal when the reproduced signals are not reproduced from a non-recorded region, and controlled by the second control signal when the reproduced signals are reproduced from a recorded region.

Abstract: A recording and reproducing apparatus is provided which includes a recording condition control device for controlling recording conditions during recording of a binary-coded original recording signal on a recording medium, a signal recording device for recording the original recording signal onto the recording medium according to recording conditions set by the recording condition control device, a reproducing signal output device for outputting binary-coded reproducing signals by detecting the recording signal as recorded on the recording medium by the signal recording device, and a recording condition setting device for obtaining the recording conditions to provide a reproducing signal approximately equal to the original recording signal through a comparison between the reproducing signal outputted from the reproducing signal output device and the original recording signal.

Abstract: A magneto-optic storage media is provided with two defect information blocks for storing information concerning a defect. At the time of reproduction, both the blocks are read, and it is determined whether or not the reading operation is normal. If the reading operations of both the blocks are normal, it is determined which of the respective numbers= of registrations of the information concerning a defect stored in both the blocks is larger so that the block in which the number of registrations is larger is utilized. Then, the defect information in the block which was not employed is updated and registered with the defect information. if the defect information is not registered, the block is switch so that an updating and registering operation can be executed again.

Abstract: An magneto-optical memory device for recording, reproducing or erasing information by applying an optical beam such as a laser beam onto a magneto-optical recording medium, the magneto optical memory device including a recorded region detecting circuit for detecting information recorded region formed in the recording medium. In the memory, a timing control for recording, reproducing or erasing is performed with the use of one result obtained through detection of a synchronizing signal such as a sector mark indicative of a starting point of an information block and another result obtained through detection in the recorded region detecting circuit.

Abstract: A disk recording checking method in which recording is performed on a disk having radially different recording tracks each divided circumferentially into a plurality of sectors. The method employs a continuous writing device for continuously writing data onto a predetermined number of the sectors, and a continuous checking device for checking the data, while continuously reading the data from the predetermined number of the sectors. The method utilized checks both the number of errors in each code sequence and the total number of errors in each sector to determine if the data in the sector is valid.

Abstract: An optical magnetic memory device includes an optical magnetic recording medium such as a disc having recording magnetic film at least on one side thereof and initialized in a certain direction in advance, a recording section for recording data in such a manner that data-recorded portions and non-recorded portions are alternately formed, and a reproducing section for reproducing data from the recording medium by detecting the interval between the recorded or non-recorded portions. The reproducing section comprises a detector for detecting positive and negative peaks of signals reproduced from the recorded or non-recorded portion and a selector for selecting either of the detection outputs from the detector according to a control signal.

Abstract: An optical memory device for recording, reproducing or erasing information by applying an optical beam such as a laser beam onto a recording medium in which the optical memory device includes a recorded region detecting circuit for detecting information recorded in a specified region formed in the recording medium. The optical memory device also includes a timing control for recording, reproducing or erasing data with the use of one result obtained through detection of a synchronizing signal such as a sector mark indicative of a starting point of an information block and another result obtained through detection in the recorded region detecting circuit. The recorded region detecting circuit contains either of at least one peak hold circuit for detecting a peak level of the playback signal and a low pass filter for smoothing the playback signal, and a comparator for comparing an output obtained through the peak hold circuit or through the low pass filter with a reference voltage.

Abstract: A disk recording method in which recording is performed on a disklike recording medium having a radially coaxial or spiral recording track that is divided into a predetermined plural number of recording sectors each acting as a recording unit. A predetermined number of dedicated sectors are provided at a rear portion of the recording track so that the contents that are recorded in defective sectors of the recording sectors are alternatively assigned to the dedicated sectors.

Abstract: An automatic gain control device for use in an optical memory device has a circuit for producing an amplification control signal which is fed back to a gain control amplifier through a sample-hold circuit. A pulse train detection circuit is provided for detecting the pulse train indicating that the data stored are a on the optical memory device is being playedback. When the pulse train is detected, the sample-hold circuit is made inactive so that the amplification control signal is directly fed back to the gain control amplifier, and when the pulse train ends, the sample-hold circuit is made active to hold the amplification control signal obtained at the end of the pulse train and to produce the amplification control signal held in the sample-hold circuit.

Abstract: An analog signal switching device for use in an optical memory device having a recording/erasing mode and a mode other than the recording/erasing mode is disclosed. The switching device includes a source for producing a switch control signal which is HIGH during the recording/erasing mode and LOW during the mode other than the recording/erasing mode. An analog switch is provided for receiving a direct input analog signal and a held input signal and for providing as output the direct input signal during the LOW state of the switch control signal, and the held input signal during the HIGH state of the switch control signal by a switching operation.

Abstract: A data modulation/demodulation system reproducing data that is divided and recorded in a plurality of blocks on a recording medium. The data modulation/demodulation system utilizes the steps of modulating the data by adding specified data bit patterns to the data bits of each block and reproducing the data which have been obtained by adding specified code bit patterns. The bit rows are independently demodulated by demodulation clocks which differ in phase. The demodulation bit pattern of the above code bit pattern which was added at the time of recording and the bit pattern which was demodulated by the different modulation clocks are compared with each other to determine which data is wrong. The correct demodulated data is selected according to this comparison and transmitted.