摘要:
An improved optical pick-up apparatus capable of reading data irrespective of disc type capable of reading various kinds of discs having different thicknesses and writing densities using only one pick-up apparatus, which includes a light source; a beam splitter for passing through or splitting a beam from the light source; an objective lens for condensing the beam onto corresponding disc among discs having different thicknesses and different densities; a numerical aperture control unit for controlling an effective numerical aperture of the objective lens so as to execute a focussing operation with respect to a certain disc; and a photodetector for receiving the beam reflected by the disc and transmitted from the beam splitter.
摘要:
On an optical disk, video object sets (VTST.sub.-- VOBS) to be reproduced and video title set information (VTSI) serving as management information on the video object sets have been stored. In each video object set (VTST.sub.-- VOBS), many data cells, each containing video, audio, and sub-picture data, are arranged. Management information on programs chains, which are combinations of programs to be reproduced one after another, has been written in a video title set PGC table (VTS.sub.-- PGCIT). By referring to the program chain table (VTS.sub.-- PGCIT) according to the user's input, the playback order of the program chains can be changed, enabling the program chains to be reproduced one after another in various modes.
摘要:
A first host interface circuit for an MO and a second host interface circuit for a CD are provided in order to allowing a common apparatus of two kinds of medium to be seemed as independent drives, for example, a CD player and an MO drive for a host. The first host interface circuit for the MO and the second host interface circuit for the CD are allocated to a master and a slave by peculiar ID numbers in a host interface. The first host interface circuit for the MO executes a reception of a command for the MO from and a response to the host interface. The second host interface circuit for the CD executes a reception of a command for the CD from and a response to the host interface.
摘要:
An optical information recording medium which can be played back by both a playback system for an SD (Super-density Disk) and a playback system for an HDMCD (High Density Multimedia Compact Disk), or by both the playback system for the SD and a playback system for a CD (Compact Disk). The optical information recording medium comprises a first transparent substrate which includes a smooth surface, and a first information surface bearing pits correspondent to first recorded information, the first information surface being covered with a semitransparent film which transmits part of a playback beam and reflects part thereof; and a second transparent substrate which includes a smooth surface, and a second information surface bearing pits correspondent to second recorded information, the second information surface being covered with a reflective film which reflects the greater part of the playback beam; the second transparent substrate being stacked on the first transparent substrate with the first information surface of the latter overlaid by the smooth surface of the former.
摘要:
An optical disk includes a user accessible area having a plurality of blocks and flag data recorded on the optical disk. The flag data indicates whether or not each of the blocks is in an erased state in which there is no recorded data. A flag area stores the flag data, and area data indicating that the optical disk has the flag area is recorded on the optical disk.
摘要:
An apparatus for playing back an optical recording medium automatically and quickly identifies the kind of optically recorded disc (CD or DVD) loaded in the apparatus. After a disc to be checked has been loaded in the apparatus, the disc is first driven in a DVD servo mode. If a peak value of a focus error signal detected in this mode is larger than a threshold value, the checked disc is recognized as a DVD. If the detected peak value of the focus error signal is smaller than the threshold value, the checked disc is thereafter driven in a CD servo mode. The checked disc is recognized as a CD if a peak value of a focus error signal detected in this mode is larger than a threshold value, which may be different from the above-mentioned threshold value.
摘要:
A trading card optical compact disc and method of using and forming the compact disc are provided which are compatible with a disc reader having a centrally located spindle and a seating ring for supporting and rotating a compact disc positioned thereon. The trading card optical compact disc according to an embodiment of the invention preferably has at least a first plastic rectangular layer having a width of about 2.5 inches and a length of about 3.5 inches and having a pattern of digital data encoded thereon. A second metallic layer is formed on at least portions of the first plastic layer, and a third protective layer is formed on at least the second layer for protecting the metallic layer. An indicia bearing fourth layer is formed on the third layer and has a generally planar upper surface for displaying indicia therefrom. An opening extends through the first, second, third, and fourth layers in a medial portion thereof. A trading card interface seat is preferably integrally formed in at least the first layer for seating the trading card onto a loading tray of a disc reader so as to interface with only portions of the seating ring of the disc reader and to read digital data stored thereon from the trading card optical compact disc.
摘要:
CD-ROMS of poor quality, such as those having eccentric center holes or uneven weight distributions circumferentially, are easy to wobble or otherwise vibrate when driven at high speed, overloading tracking and focusing servos and inviting read errors and retries. Each CD-ROM on being loaded into a CD-ROM drive is therefore checked as to its quality in terms of the speed of rotation at which the disk drive motor gains a steady state on being started up at a full supply voltage. The poorer the disk quality, the lower is the steady state speed of motor rotation. A poor quality disk is read at four times the standard audio CD speed, an intermediate quality disk at eight times that speed, and a good quality disk at twelve times that speed.
摘要:
An integrated calibration apparatus operates in multiple calibration modes of a multi-mode information storage system such as an optical disk drive to calibrate the drive in the multiple write modes. An event processing and measurement circuit is configurable in multiple configurations that each correspond to a different calibration measurement. Each configuration concurrently measures one or more parameters of readback data written to an optical disk by the optical disk drive operating in a particular write mode. A qualification circuit selects valid measurements for two different parameters or for two different qualification of the same parameter. A summation circuit sums valid measurements of each parameter measured and counts the number of measurements summed for each parameter. The calibration apparatus calculates average values for the measured parameters from the sums and counts, and then calibrates the multi-mode optical disk drive for its current write mode based on the average values.
摘要:
A disk discrimination method for a digital versatile disk (DVD) system uses a sum signal and a focus error signal as a difference signal obtained from the amount of light detected from divided optical detection areas of a divided-by-eight photodiode in a loaded disk, to discriminate whether a loaded disk is a DVD or compact disk (CD). When offsets of the sum signal and the focus error signal are normal, and are larger than predetermined reference signals, it is judged that the loaded disk is a DVD, while the loaded disk is judged to be a CD when the sum signal and the focus error signal are smaller than the reference signals. When disk type discrimination fails, an optical pickup moves a predetermined number of times to retry discrimination. Such discrimination method increases reliability of the discrimination results.