The Minidisc related patents that follow were found by searching
public domain patent documents available from the US Patent and Trademark Office website
for keywords such as ATRAC and Minidisc. They represent a wealth of
information for those wishing to dig into Minidisc's roots and
evolution.
The patents are interesting for several reasons. Foremost, they
describe each invention's prior art and background. In that
description are meaty details of the Minidisc system, covering such
topics as the ATRAC compression system, laser optics, servo control,
and the MD's logical data layout. The patents are also interesting
because, through them, one can track the improvements that have been
made to Minidisc technology over the years. There are patents covering
battery power conservation, ATRAC enhancements (including the advent
of ATRAC2), mechanism and drive refinements, etc. Finally, the
patents provide a means of tracing the historical evolution of
Minidisc technology. They show Minidisc's derivation from the audio CD
(and the subsequent, but never productized, CD-MO [Magneto-Optical])
as well as intriguing glimpses of paths the designers pursued during
development (e.g. the specification of CD-I's "B"
mode audio [37.8 khz sampling, ADPCM @ 4 bits/sample] for the format in US05224087 until (I
suspect) their tentative collaboration with Philips exposed them to
the wisdom of perceptual coding).
As for how to read the patents, I can only recommend a dogged,
methodical approach. It is odd that these documents, intended to
explain a practice precisely, end up being pedantic and verbose to the
point of near unreadability! I am not sure what the patent lawyers
have in mind, but perhaps it is felt that this style of English is so
bad already that it cannot really be threatened by the passage of
time. Whatever its purpose, the language in these documents makes
skimming to get the gist of them difficult. I found the most
informative sections the Background of the Invention and the
subsequent Summary of the Invention. If you have the stamina (I
didn't), try slogging through the Detailed Description of the
Preferred Embodiment. This will tell you in nitty-gritty detail
what, in particular, is being disclosed.
I have heard that a patent filing typically runs about
US$50,000. Perhaps we can think of these documents then, with their
obscure and redundant language, as the Sutras of our technological
age. Assembled at great cost, impenetrable to the uninitiated, they
hold the hard won secrets of the world's technical priesthood. May you
read, digest, and be nourished.
| US05301205 | Apparatus and method for data compression using signal-weighted quantizing bit allocation |
| abstract full | Sony Corporation | Assign./Filed: April 5, 1994/ Jan. 29, 1993 |
| ATRAC - includes detailed discussion of ATRAC's bit allocation method. |
|
| US05381143 | Digital signal coding/decoding apparatus, digital signal coding apparatus, and digital signal decoding apparatus |
| abstract full | Sony Corporation | Assign./Filed: Jan. 10, 1995/ Sept. 8, 1993 |
| Enhancement to ATRAC. Detailed description of ATRAC's Block Floating operations. Some commonality with US05301205. |
|
| US05388209 | Apparatus for high-speed recording compressed digital data with increased compression |
| abstract full | Sony Corporation | Assign./Filed: Feb. 7, 1995/ July 31, 1992 |
| Method of stripping out redundant information in ATRAC for further compression into a variable bit rate stream (for recording to a high cost storage device e.g. IC card memory). |
|
| US05394473 | Adaptive-block-length, adaptive-transforn, and adaptive-window transform coder, decoder, and encoder/decoder for high-quality audio |
| abstract full | Dolby Laboratories Licensing Corporation | Assign./Filed: Feb. 28, 1995/ Dec. 11, 1991 |
| Transform audio coding with adaptive block length, transform and window. This patent (at least) must cover some of the IP embodied in Minidisc's ATRAC. Description has commonality with other Dolby patents. |
|
| US05454011 | Apparatus and method for orthogonally transforming a digital information signal with scale down to prevent processing overflow |
| abstract full | Sony Corporation | Assign./Filed: Sept. 26, 1995/ Nov. 23, 1993 |
| ATRAC enhancement. Strong similarity to US05381143. |
|
| US05461378 | Digital signal decoding apparatus |
| abstract full | Sony Corporation | Assign./Filed: Oct. 24, 1995/ Sept. 8, 1993 |
| ATRAC decoding enhancement. Similarity to US05381143. |
|
| US05471558 | Data compression method and apparatus in which quantizing bits are allocated to a block in a present frame in response to the block in a past frame |
| abstract full | Sony Corporation | Assign./Filed: Nov. 28, 1995/ Sept. 29, 1992 |
| ATRAC enhancement? Good discussion of Pre-echo. Does not share simlarity with other ATRAC patents. |
|
| US05490170 | Coding apparatus for digital signal |
| abstract full | Sony Corporation | Assign./Filed: Feb. 6, 1996/ Nov. 30, 1993 |
| Block floating enhancement. Similarity to other ATRAC patents. |
|
| US05734792 | Enhancement method for a coarse quantizer in the ATRAC |
| abstract full | Matsushita Electric Industrial Co., Ltd. | Assign./Filed: March 31, 1998/ Dec. 6, 1993 |
| Improvement to ATRAC encoder to reduce quantization noise. |
|
| US05819211 | Adaptive transform acoustic coding circuit formed in a single application specific integrated circuit of a mini disk system |
| abstract full | Samsung Electronics Co., Ltd. | Assign./Filed: Oct. 6, 1998/ Feb. 26, 1996 |
| Integrated circuit for decoding ATRAC. Gives explicit timings and RAM requirements for the ATRAC decoding operation. |
|
| US05825320 | Gain control method for audio encoding device |
| abstract full | Sony Corporation | Assign./Filed: Oct. 20, 1998/ March 13, 1997 |
| Gain control method for handling pre-echo used by ATRAC2/3. |
|
| US05960390 | Coding method for using multi channel audio signals |
| abstract full | Sony Corporation | Assign./Filed: Sept. 28, 1999/ Oct. 2, 1996 |
| ATRAC2/3 Gain Control. |
|
| US05974379 | Methods and apparatus for gain controlling waveform elements ahead of an attack portion and waveform elements of a release portion |
| abstract full | Sony Corporation | Assign./Filed: Oct. 26, 1999/ Feb. 21, 1996 |
| ATRAC2/3 Gain Control. |
|
| US06138101 | Method of encoding digital data |
| abstract full | Sharp Corporation | Assign./Filed: Oct. 24, 2000/ Dec. 4, 1997 |
| Improvement to ATRAC which allows a more flexible interpretation of "minimum limit of audibility" depending upon the signal characteristics. |
|
| US04516258 | Bit allocation generator for adaptive transform coder |
| abstract full | AT&T Bell Laboratories | Assign./Filed: May 7, 1985/ June 30, 1982 |
| Adaptive bit allocation scheme for transform speech encoders. Seems to predate using perceptual distortion criteria. |
|
| US05109417 | Low bit rate transform coder, decoder, and encoder/decoder for high-quality audio |
| abstract full | Dolby Laboratories Licensing Corporation | Assign./Filed: April 28, 1992/ Dec. 29, 1989 |
| Use of block floating representation and adaptive bit allocation for encoding high quality audio. Gives nicely detailed, general coverage of transform coding. |
|
| US05142656 | Low bit rate transform coder, decoder, and encoder/decoder for high-quality audio |
| abstract full | Dolby Laboratories Licensing Corporation | Assign./Filed: Aug. 25, 1992/ Nov. 4, 1991 |
| Fancy adaptive bit allocation method using fixed offsets (seems a lot like the one ATRAC uses). Appears to be large overlap with US05109417. |
|
| US05166686 | Variable length block coding with changing characteristics of input samples |
| abstract full | NEC Corporation | Assign./Filed: Nov. 24, 1992/ June 29, 1990 |
| Transform coding with adaptable input block size. |
|
| US05197087 | Signal encoding apparatus |
| abstract full | none | Assign./Filed: March 23, 1993/ July 18, 1990 |
| Transform coding with adaptable input block size. |
|
| US05222189 | Low time-delay transform coder, decoder, and encoder/decoder for high-quality audio |
| abstract full | Dolby Laboratories Licensing Corporation | Assign./Filed: June 22, 1993/ Sept. 26, 1990 |
| High quality audio at 128kbps with a very short block size (128 samples). Again, considerable overlap (read: boilerplate) with previous Dolby patents. |
|
| US05235623 | Adaptive transform coding by selecting optimum block lengths according to variatons between successive blocks |
| abstract full | NEC Corporation | Assign./Filed: Aug. 10, 1993/ Nov. 14, 1990 |
| Transform coding with adaptable input block size. |
|
| US05263088 | Adaptive bit assignment transform coding according to power distribution of transform coefficients |
| abstract full | NEC Corporation | Assign./Filed: Nov. 16, 1993/ July 12, 1991 |
| Adaptive bit assignment algorithm for transform coding. |
|
| US05268882 | Magnetic head holding apparatus |
| abstract full | Sony Corporation | Assign./Filed: Dec. 7, 1993/ Dec. 8, 1992 |
| Mechanical design and mounting of the overwrite head. |
|
| US05341357 | Optical disc recording apparatus |
| abstract full | Sony Corporation | Assign./Filed: Aug. 23, 1994/ Dec. 11, 1991 |
| Method for disabling the eject button when the TOC is being written. |
|
| US05539717 | Player for reproducing both minidisc and compact disc |
| abstract full | Daewoo Electronics Co., Ltd. | Assign./Filed: July 23, 1996/ Dec. 13, 1994 |
| Covers the mechanics of a transport for both CD and MD. |
|
| US05583834 | Mini disc player |
| abstract full | Sony Corporation | Assign./Filed: Dec. 10, 1996/ Jan. 17, 1996 |
| Mechanical design of MZ-R2. |
|
| US06009062 | Disc player for minidisc and compact disc playback |
| abstract full | Victor Company of Japan, Ltd. | Assign./Filed: Dec. 28, 1999/ June 4, 1998 |
| Mechanism for combination MD/CD drive. Appears to be the basis for the JVC KD-MX3000. Contains detailed mechanical drawings of the drive. |
|
| US04608676 | Apparatus for optically reproducing an information signal from a record disk |
| abstract full | Sony Corporation | Assign./Filed: Aug. 26, 1986/ March 26, 1985 |
| Relates to the positioning of an optical head for a CD player. |
|
| US05003521 | Optical disk discriminating device |
| abstract full | Sony Corporation | Assign./Filed: March 26, 1991/ Aug. 18, 1988 |
| Discriminating between recordable and pre-recorded discs. |
|
| US05012461 | Disk recording apparatus for re-establishing a recording mode at a desired address |
| abstract full | Sony Corporation | Assign./Filed: April 30, 1991/ Oct. 21, 1988 |
| Detecting mis-tracking during recording (by watching the ADIP addresses). |
|
| US05357498 | Disc drive apparatus that positions an objective lens within a disc cartridge at the time when the disc is rotated |
| abstract full | Sony Corporation | Assign./Filed: Oct. 18, 1994/ Sept. 14, 1992 |
| Optical head arrangment where the head is moved close to the disk through the shutter opening in the cartridge. |
|
| US05428596 | Optical pickup apparatus |
| abstract full | Sony Corporation | Assign./Filed: June 27, 1995/ June 23, 1994 |
| Details of the MD optical pickup. |
|
| US05475537 | Optical system for use in recording and reading information on an optical information medium |
| abstract full | Konica Corporation | Assign./Filed: Dec. 12, 1995/ Feb. 28, 1994 |
| Optical pickup optics. |
|
| US05644563 | Optical pickup system |
| abstract full | LG Electronics Inc. | Assign./Filed: July 1, 1997/ June 7, 1995 |
| Optical pickup details. |
|
| US05673247 | Optical pickup having two objective lenses |
| abstract full | Sharp Corporation | Assign./Filed: Sept. 30, 1997/ Nov. 27, 1996 |
| Double lens optical pickup. Good drawings of the optical path details. |
|
| US05737297 | Optical head |
| abstract full | Sharp Corporation | Assign./Filed: April 7, 1998/ Feb. 11, 1997 |
| Improved MD optical head. |
|
| US05844882 | Recording medium, address recording method and apparatus, and recording/reproducing method and apparatus for reducing crosstalk of addressing signals |
| abstract full | Sony Corporation | Assign./Filed: Dec. 1, 1998/ March 17, 1997 |
| Improvement to allow accurate, low cross-talk ADIP tracking even with small track pitch. (Beneficial for 80 minute blanks with 1.5um pitch?). Includes very careful description of how ADIP tracking is accomplished. |
|
| US04907216 | Optical record carrier having position indentifying track modulation |
| abstract full | U.S. Philips Corporation | Assign./Filed: March 6, 1990/ Dec. 9, 1987 |
| Method for storing address information in a recordable disc's pregroove. Different from MDs modulated ADIP wobble however. |
|
| US04910622 | Over write capable magnetooptical recording medium |
| abstract full | Nikon Corporation | Assign./Filed: March 20, 1990/ May 10, 1988 |
| Magnetic overwrite system in which 2 bits can be stored per magnetic domain. |
|
| US05050145 | Optical disk recording and reproducing apparatus having faster reproducing speed than recording speed |
| abstract full | Sony Corporation | Assign./Filed: Sept. 17, 1991/ Jan. 22, 1990 |
| CD-MO system in which playback rotational speed is higher than recording rotational speed. |
|
| US05400316 | High density small-diameter magnetic optical disk |
| abstract full | Sony Corporation | Assign./Filed: March 21, 1995/ Aug. 15, 1991 |
| Coverage of the MD substrate, and methods for molding it. By reducing double refraction the inner circumfrences of the disc are made available for recording. |
|
| US05461597 | Mastering apparatus for producing compact disk and minidisk master disks |
| abstract full | Sony Corporation | Assign./Filed: Oct. 24, 1995/ June 29, 1993 |
| Description of the Minidisc mastering process. |
|
| US05506023 | Magneto-optical disc |
| abstract full | Sony Corporation | Assign./Filed: April 9, 1996/ Aug. 26, 1994 |
| Optical disc with description of the lubrication layer for the magnetic head. |
|
| USRE034710 | Magneto-optical recording apparatus |
| abstract full | Sony Corporation | Assign./Filed: Aug. 30, 1994/ July 16, 1993 |
| Patent for magnetic overwrite recording and direct contact head. |
|
| US04858217 | Optical disk recording and reproducing device |
| abstract full | Sony Corporation | Assign./Filed: Aug. 15, 1989/ Nov. 16, 1987 |
| Recordable CD patent. Relates to handling of the long interleaved CIRC when a new audio segment is recorded. |
|
| US05224087 | Apparatus for recording compressed digital information to an optical disc |
| abstract full | Sony Corporation | Assign./Filed: June 29, 1993/ Aug. 19, 1991 |
| Use of shock memory for compressed audio, plus interleave issues. This is an ur-Minidisc patent, discussing recording of compressed audio to optical disk, albeit with an unprotected carrier (see discussion starting page 11). |
|
| US05243588 | Method and apparatus for reading digital data bursts comprising data clusters and cluster linking sectors |
| abstract full | Sony Corporation | Assign./Filed: Sept. 7, 1993/ Aug. 16, 1991 |
| Similar to US05224087, discussing the necessity of the cluster-linking sector (used as a place for the error correction code to run out). |
|
| US05363362 | Apparatus for reproducing recorded data comprising interleaved clusters and cluster linking sectors |
| abstract full | Sony Corporation | Assign./Filed: Nov. 8, 1994/ April 15, 1993 |
| Similar to US05224087 and US05243588, discussing the necessity of the cluster-linking sector (used as a place for the error correction code to run out). |
|
| US05528570 | Apparatus for recording and reproducing data on a magneto-optical disc at a data transfer rate which is the same as that of data reproduced from a compact disc |
| abstract full | Sony Corporation | Assign./Filed: June 18, 1996/ Feb. 24, 1994 |
| MD-Data related. Nice explanation of the long interleave and the reason for link sectors. Detailed description of the MD's physical data level. |
|
| US04862439 | Recording device that identifies recordable areas of a disk record |
| abstract full | Sony Corporation | Assign./Filed: Aug. 29, 1989/ Jan. 19, 1988 |
| How to use TOC information to determine where there is available recording space on a medium; apparently for recordable CD. |
|
| US05038231 | Recording and reproducing apparatus which repositions table of contents information from one area to another on the medium |
| abstract full | Canon Corporation | Assign./Filed: Aug. 6, 1991/ Jan. 24, 1990 |
| Recording a TOC on tape (DAT, etc). |
|
| US05153861 | Recording/reproducing device |
| abstract full | Sharp Corporation | Assign./Filed: Oct. 6, 1992/ Dec. 13, 1989 |
| Allow user information to be added to the TOC of recordable CD. |
|
| US05274617 | Method and device for data management in an optical recording medium |
| abstract full | Sharp Corporation | Assign./Filed: Dec. 28, 1993/ May 25, 1990 |
| Method of detecting and doing something useful in cases where the TOC is out of date with respect to the disc contents. |
|
| US05388093 | Disc recording and/or reproducing apparatus for recording continuous compressed data in plural data regions and disc therefor |
| abstract full | Sony Corporation | Assign./Filed: Feb. 7, 1995/ Sept. 16, 1992 |
| General Minidisc description that includes details of the TOC layout. Some commonality with US05363362. |
|
| US05392265 | Recording and reproducing apparatus which calculates and displays management information of recorded segments |
| abstract full | Sony Corporation | Assign./Filed: Feb. 21, 1995/ May 17, 1993 |
| Use of TOC information to display playing time of a track, total playing time, and recording time remaining. Includes careful description of TOC contents. |
|
| US05521900 | Disk having a lead-in region containing display data and an apparatus for recording and/or reproducing the disc |
| abstract full | Sony Corporation | Assign./Filed: May 28, 1996/ Dec. 21, 1993 |
| Details of the TOC (but perhaps not the current MD TOC). Similar to US05214631. |
|
| US05537387 | Information storage disk with display data recorded in a lead-in region and an apparatus for recording and/reproducing the disc |
| abstract full | Sony Corporation | Assign./Filed: July 16, 1996/ May 11, 1995 |
| TOC related. Very similar to US05521900. |
|
| US05148417 | Tracking jump compensator for optical disc reproducing apparatus |
| abstract full | Sony Corporation | Assign./Filed: Sept. 15, 1992/ April 23, 1990 |
| Shock proof memory (embodiment in CD). |
|
| US05214631 | Disc recording/reproducing apparatus having a servo system capable of successively recording and reproducing tracks on a disc irrespective of turbulence of the servo system due to a disturbance |
| abstract full | Sony Corporation | Assign./Filed: May 25, 1993/ June 19, 1991 |
| Shock proof memory as it applies to CD-I (CD Interactive). Interesting discussion of CD-I audio modes. |
|
| US05331617 | Audio data recording/reproduction device having digital high speed dubbing function and audio data dubbing system using such devices |
| abstract full | Sanyo Electric Co., Ltd. | Assign./Filed: July 19, 1994/ May 27, 1993 |
| Contains diagrams of shock proof memory levels as the memory drains and refills. |
|
| US05317553 | Optical disc recording and/or reproducing apparatus having a buffer memory to accommodate track jumps |
| abstract full | Sony Corporation | Assign./Filed: May 31, 1994/ Aug. 15, 1991 |
| Minidisc - shock proof memory. |
|
| US05680379 | Information reproduction apparatus having means to control maximum delay of information being read from memory |
| abstract full | Mitsubishi Denki Corporation | Assign./Filed: Oct. 21, 1997/ April 19, 1993 |
| Shock-proof buffer management technique to reduce mute time during inadvertent track skip and upon user initiated disk change. |
|
| US05222054 | Seeking operation control apparatus in an optical disk reader |
| abstract full | Funai Electric Co., Ltd. | Assign./Filed: June 22, 1993/ Sept. 17, 1991 |
| Optimization of track jump operations, by calculating the number of tracks that need to be skipped. |
|
| US05343452 | Data recording/reproducing apparatus of simultaneously performing both reproducing and recording from and in a single recording medium |
| abstract full | Sharp Corporation | Assign./Filed: Aug. 30, 1994/ Nov. 19, 1992 |
| Method for playing back and recording simultaneously. The MDS-DRE1 must have used a scheme such as this. |
|
| US05508984 | Optical disc player having program title display |
| abstract full | Corporation Kenwood | Assign./Filed: April 16, 1996/ Oct. 28, 1993 |
| Method of displaying TRACK TIME or TRACK NAME by use of a user key. |
|
| US05563861 | Optical disc recording apparatus which controls re-recording after a disturbance as a function of the frequency of the detected disturbance |
| abstract full | Sony Corporation | Assign./Filed: Oct. 8, 1996/ May 11, 1995 |
| Related to detecting track jumps and re-recording affected sections. Good description of physical level recording and playback functions. |
|
| US05568625 | Time conversion method of mini discs using multiple time tables |
| abstract full | Samsung Electronics Co., Ltd. | Assign./Filed: Oct. 22, 1996/ Oct. 31, 1994 |
| Method for converting MD physical addresses to hours, minutes and seconds.. |
|
| US05699336 | Reproducing apparatus having buffer memory and capable of rapidly restarting reproduction and method of controlling the apparatus |
| abstract full | Sony Corporation | Assign./Filed: Dec. 16, 1997/ Jan. 18, 1996 |
| Decrease track-seek delay in portables by storing beginning of next track and beginning of previous track in shock-proof memory, so that if the user issues a track-seek, the adjacent track can be immediately played out while waiting for the optical head to power up, seek to position, and begin reading. |
|
| US05706262 | Recording and reproducing apparatus that allows user reordering of the sequence that data is reproduced from the disc and that automatically reorders the remaining data after data defined by the user has been erased |
| abstract full | Sony Corporation | Assign./Filed: Jan. 6, 1998/ Aug. 1, 1996 |
| Method to allow users to delete or renumber multiple tracks at once, reducing confusion caused by tracks changing their numbering when these operations are attempted one at a time. |
|
| US05889745 | Method for calculating a play time of a disc reproducing apparatus |
| abstract full | Sony Corporation | Assign./Filed: March 30, 1999/ May 18, 1993 |
| Calculating play time by finding the number of clusters in a track. |
|
| US05546369 | Optical disk system for recording and reproducing a mini disk and standard compact discs |
| abstract full | Samsung Electronics Co., Ltd. | Assign./Filed: Aug. 13, 1996/ March 30, 1995 |
| CD and MD recorder with the ability to store ATRAC data on a CD. |
|
| US05592449 | Disc apparatus using character-based control codes in a table of contents |
| abstract full | Corporation Kenwood | Assign./Filed: Jan. 7, 1997/ Nov. 14, 1995 |
| Using character information placed in the track title area to control devices external to the MD player. |
|
| US05689704 | Recording medium, recording/playback device which uses commands in character string form for audio system control |
| abstract full | Sony Corporation | Assign./Filed: Nov. 18, 1997/ May 18, 1995 |
| Scheme for adding interactivity (as with CD-I) to MD equipment by storing equipment control commands on an MD. Functions such as playback, recording, editing, as well as computation, could be undertaken according to control information recorded on the MD. Contains a drawing of the MZ-1 and detailed information on the TOC contents. |
|
| US05856930 | Disc-shaped recording medium, disc recording apparatus and disc reproducing apparatus |
| abstract full | Sony Corporation | Assign./Filed: Jan. 5, 1999/ Nov. 14, 1994 |
| Technique to be used when encoding MPEG video on Minidisc, placing I frames and B frames strategically with respect to linking sectors. Contains interesting drawing of pocket Minidisc video viewer ("MD Watchman"?). |
|
| US05901119 | Recording apparatus, playback apparatus and recording medium having a management area with program position and playback information |
| abstract full | Sony Corporation | Assign./Filed: May 4, 1999/ Aug. 18, 1997 |
| Use of a previously unused region of the MD to store various disc-based settings, such as program play order, and track "quick-start" indication (this being a mode used in sound effects applications wherein the audio at the beginning of a track is held in buffer memory to provide immediate playback at the push of a button). (Does the Tascam pro deck use this?) |
|
| US05940352 | Record medium device for recording and reproducing time codes synchronized with input/reproduction signals into and from record medium having UTOC area, and record medium having UTOC area |
| abstract full | Nippon Columbia Co. Ltd. | Assign./Filed: Aug. 17, 1999/ Sept. 18, 1997 |
| Method for recording video timecodes to Minidisc, storing them in the UTOC. (Nippon Columbia is otherwise known as Denon). |
|
| US06097557 | Method and apparatus for recording compressed audio data on recording medium and method for transferring compressed audio data |
| abstract full | Sony Corporation | Assign./Filed: Aug. 1, 2000/ May 27, 1998 |
| Method for updating the U-TOC in a Minidisc Kiosk based music delivery system. Here they describe that the local Kiosk equipment should, after recording the compressed audio data to the disc, determine the new U-TOC contents, rather than having the central server determine this. (Seems rather obvious). |
|
| US04932016 | Apparatus and method of recording and reproducing data using a disk |
| abstract full | Sony Corporation | Assign./Filed: June 5, 1990/ June 2, 1988 |
| Finding and recording the start and end times of audio being recorded. For recordable CD. |
|
| US05963521 | Recording and/or reproducing method and apparatus with dubbing mode |
| abstract full | Sony Corporation | Assign./Filed: Oct. 5, 1999/ Sept. 11, 1998 |
| High speed dubbing in the ATRAC domain. |
|
| US06205104 | Recording/reproducing apparatus for compressed data |
| abstract full | Sony Corporation | Assign./Filed: March 20, 2001/ Sept. 29, 1993 |
| High speed dubbing in the ATRAC domain. |
|
| US06005659 | Mini-disc laser power meter and method of making the same |
| abstract full | Sony Corporation | Assign./Filed: Dec. 21, 1999/ Dec. 15, 1998 |
| MD Laser power meter with the sensor unit in the shape of a Minidisc cartridge. The sensor can be inserted in a piece of MD equipment for laser power measurement without requiring any disassembly. |
|
| US06035367 | Computer file system providing looped file structure for post-occurrence data collection of asynchronous events |
| abstract full | Avid Technology, Inc. | Assign./Filed: March 7, 2000/ April 3, 1997 |
| Relates to storing video on a hard disk in much the way that the Minidisc "Time machine" recording function works. Interestingly, this patent references Minidisc.org(!), refering to information there about the Sony MDS-503. |
|
| US06157434 | Movie film having two digital audio data recording areas along its longitudinal direction |
| abstract full | Sony Corporation | Assign./Filed: Dec. 5, 2000/ Dec. 13, 1993 |
| Method of recording ATRAC on movie film. |
|
