GB2232805A - Audio or video disc and reproduction apparatus therefor - Google Patents

Abstract

Apparatus for reproducing an audio and/or video work from a disc having that work recorded on a playing surface thereof, comprising first reading means for reading the playing surface, means for processing a signal from the first reading means to produce a required output, and a second reading means (9 to 11) for reading machine-readable information (in tracks 5 to 7) from a surface of the disc opposite to the playing surface, and for producing an information signal. That information will contain details of the disc and of the individual tracks thereon, and will be automatically read into a memory device (13) following loading of the disc, eg for locating discs in a juke box. <IMAGE>

Description

AUDIO OR VIDEO DISC AND REPRODUCTION APPARATUS THEREFORE This invention relates to a disc from which an audio and/or video work may be reproduced, and to apparatus for reproducing such work from the disc. It is particularly concerned with facilitating the management of juke boxes, but has wider application.

Juke box systems are now known that will play selected audio and/or video works that are recorded on optical disc.

The systems comprise a play unit loaded with a selection of different discs, a selection unit, and control means responsive to the selection unit for controlling the play unit so as to play a selected work. The advent of the optical disc, particularly in "compact disc" form, has made it possible for juke boxes to contain a very large number of works which may be selected for play. This makes the updating of selection information on the juke box particularly laborious if a number of discs are to be changed at the same time, as usually each disc will carry anything up to 20 different works, and the potential customer will need to be able to access details of all those works.

Although manual loading of information relating to the available works into the juke boxe is possible it is obviously more efficient to do this in semi-automatic manner. Accordingly. it has already been proposed to supply with a compact disc a card carrying machine-readable information related to the disc. Using a suitable reading means the card can be read and the information carried thereon loaded into a memory store forming part of the juke box. for subsequent retrieval as necessary.

In more complex systems it has also been proposed to utilise a removable memory store in a juke box, the memory store containing information relating to the full repertory of discs carried by the juke box, and being periodically removed for updating at a control centre. After updating the removable memory, together with replacement discs as required is delivered to and installed in the juke box.

Both these systems have their disadvantages. The principle disadvantage of the first system is that the card is easily lost, so causing difficulties when a particular disc is to be removed from one juke box and transferred to another. The latter system, although excellent for operators maintaining a large number of juke boxes from a central headquarters, is unsuitable for operators managing a small number of juke boxes, where the costs of the necessary computer complex cannot be justified. The invention seeks to provide a more manageable system.

According to a first feature of the invention a disc from which an audio and/or video work may be produced has a playing surface and an opposite surface, and information in machine-readable form is carried on the opposite surface.

From another aspect of the invention, apparatus for reproducing an audio and/or video work from a disc haivng that work recorded on a playing surface thereof comprises first reading means for reading the playing surface, means for processing a signal from the first reading means to produce a required output, and a second reading means for reading machine-readable information from a surface of the disc opposite to the playing surface, and for producing an information signal.

The use of the invention in relation to a juke box will be apparent. A new disc is loaded into a given store location within the juke box. The juke box is then operated so that the disc at that store location is selected and is moved to a play position, where play commences. As the disc is rotated at the play position the second reading means reads the machine-readable information from the oppposite surface of the disc. That information will generally be read into a memory of the juke box by a control microcomputer for the juke box. When all necessary information has been read the play can be aborted and the disc then returned to its store location. The operation is repeated for each new disc loaded into the system and the memory of the juke box is thereby updated.

Information relating to a particular disc is always present on the opposite surface of the disc, and can thus not be lost. Furthermore, there is no possibility of mismatching disc location and disc information. This is because the disc information is only read into memory after the disc has actually physically been loaded into its store location.

The information may be optically, magnetically or capacitatively coded, with the reading means accordingly comprising an optical, magnetic or capacitative reading head.

It is preferred that the information is contained in one or more circular tracks that are concentric with the disc, and that the reading means then comprises a plurality of reading heads, each mounted at a separate fixed location and each location being a different radial distance from the axis of rotation of drive means for the disc.

In an alternative arrangement, the information may be contained in one or more tracks spiralling inwardly towards the centre of the disc, and the reading means then comprises at least one reading head, and means for tracking the reading head or heads across the surface of the disc. This is obviously a much more complicated system, and the use of fixed heads is preferred. However, if the available number of circular tracks cannot store all the required relevant information then a tracking system may be necessary.

The information that will be carried on the opposite surface of the disc will usually comprise details of the disc and of individual tracks thereon. When a memory is provided in the juke box this may be in two sections, the first storing details of the disc, and the second storing details of individual tracks. This split storage arrangement may facilitate display and selection of individual works. Thus, information from the disc information section may initially be displayed on a display means, and once a particular disc has been selected by the user the disc information may be replaced by information concerning the individual tracks on the selected disc. A further selection will then be made, by the user in order to initiate play of the desired track.

In addition to storing information relating to the disc it may also be possible for the information on the opposite surface of the disc to include monitoring and control information. For example, the information may include a code identifier for the disc to assist in monitoring the number of times that the disc is played, or attract information relating to the disc for showing on the display unit of the juke box, or information for many other purposes.

The invention will be better understood from the following description of a specific embodiment thereof, given in conjunction with the accompanying schematic drawing.

The drawing illustrates an optical compact disc 1 of a type having a playing surface on which is recorded a number of audio tracks. The playing surface is not visible in the figure, which shows only the opposite surface 2 of the disc.

Although the following description will be written in terms of the reproduction of audio works from an optical compact disc it will be understood that the invention is equally applicable to larger optical discs and to capacitative that may carry recordings of audio works, video works or boti.

The surface 2 of the disc carries three circular tracks 4, 5 and 6, each concentric with the centre of the opening 7 by way of which the disc is supported for play. As illustrated, each of the three tracks 4 to 6 carries machine-readable information in the form of bar code data such as 7 extending along whatever arc of the track is required. The individual bars of the codes extend radially of the disc. The bar codes may be suitably printed onto a label which is then secured to the disc by an adhesive so that the tracks 4 to 6 are concentric with the disc.

Printing may be by any suitable technique and onto any suitable medium, for example a paper card or other medium that is dimensionally stable and capable of being adhered to the disc.

The figure shows the disc in its assumed position in a player, of which no details are shown. The playing head, which in the case of a compact disc is a laser reader, being located adjacent to that face of the disc not visible in the drawings. A holder 8 supports three reading heads 9 to 11, each positioned at a different radial distance from the centre of the disc and lying over a respective one of the tracks 4 to 6. Each head incorporates optical means for reading the bar code data in the tracks 4 to 6 and for converting that data into an information signal. The reading heads are connected to a microcomputer 12 by which the juke box is controlled, the microcomputer also being connected to a memory 13, to a display device in the form of a visual display unit 14 and to a selection device 15.The microcomputer is also connected to control a mechanism (not shown) for selecting individual discs and moving them from their store locations to load them into the play unit, and then for returning the discs to their store locations after play.

In order to describe operation of the apparatus, it will be assumed that it forms part of a new juke box that is being commissioned by loading it with a suitable number of compact discs. The memory is divided into two parts, store A and store B, the latter part being empty, and the former part carrying only data giving the possible disc store locations. for example locations 1 to 100. The visual display unit 14 will be blank, or it may display messages that guide the operator through the setting up operation.

Discs will be loaded as required into their store locations, and when this operation has been completed then Le loading of the memory 13 can commence. The selection control 15 is operated to select the disc at store location irrespective of whatever that disc may be. That disc is ien moved from its store location to the play location order the control of the microcomputer and rotation of the isc is commenced by the drive unit of the play location.

we first of the reading heads 9 is enabled, either by ysically switching this on, or by opening a data channel om the reading head to the microcomputer 12. As the disc states the data in track 4 is scanned by the head 9. The lta will include a data block S1 which indicates the start r the track section from which data is to be loaded into tore A of memory 13, and after detection of this starting lock the microcomputer directs the following information nto store A, relating it to the appropriate disc location.

his information will be related to the title of the disc, he composer(s), performer(s) and possibly the musical category, for example so-called "Country and Western", Middle of the Road" or Heavy Metal". The information may lso include a code identifier for the disc.

Part way round the track 5 the bar code data may nclude a sector C1 that produces a control signal directing he computer to store information following that sector in tore B rather than store A. Accordingly the following nformation will be directed into store B (following an dentifier relating that part of store B to the part of tore A holding the disc information) until a sector F1 of he track 4 is read, indicating that all data has now been aken from that track. Head 9 is then disabled, and head 10 s enabled. After passage of a start sector S2 under the ead 10 and recognition of that by the microcomputer, then ata will be read from the track 5 and loaded into store B.

ead 10 will be disabled when a finish sector F2 of track 5 s recognised, and head 11 will be enabled, to allow data to be read from track 6 once a start sector S3 has been read by head 11 and recognised by the microcomputer 12. Transfer of data terminates when a finish sector F3 of track 6 is read and recognised. The data that is read into store B of the memory relates to the individual tracks on the disc, and will obviously be more detailed than the data that has been read into store A of the memory.

Once sector F3 has been recognised by the microcomputer 12 this signals that play of the disc 1 should be aborted.

and the disc is then removed from the playing position and returned to its store location, 1. This can be observed visually by the operator. or the operator may be prompted by a message on the visual display unit telling him that he should now select the disc at store location 2. This selection is therefore made, and the second disc is presented to the play position, the information then being read into stores A and B of the memory as already described.

This operation continues until information from all discs has been loaded into the memory, and the juke box is then ready for operation.

In the standby mode of the juke box the disc title data from store A of memory 13 will be displayed in the visual display unit, together with an invitation to the user to select the disc of his choice. Once that selection has been made through the unit 15 that disc is taken from its store location and moved to the playing position. At the same time, the display on the visual display unit changes so that it shows the detail track data of the selected disc, that data being read from store B of memory 13. The user then selects the required track on the selection panel 15, and this message is received by the microcomputer and converted into a command for the track to be played. Further selections are then made as required. and are played according to whatever operating system has been adopted for the juke box.

When any disc in the juke box is to be replaced it is simply removed from its store location and the new disc inserted at that location. Selection of that disc is then made, following an appropriate control signal to indicate to the microcomputer that the data from the opposite surface of the disc is to be read. The reading process takes place as described and the data is transmitted to stores A and B of the memory 13, overwriting the data for that particular disc location that already resides in those stores. Updating is thus a rapid and simple matter.

If desired. the microprocessor may be programmed to operate during commissioning of the juke box in such a way that on detection of the finished sector S3 not only is the disc that has just been read returned to its storage location, but the disc from the next storage location is automatically selected without any need for the operator having to select from panel 15. This automatic sequential reading will desirably be disabled when individual discs are being loaded or replaced.

Although the description has been written in terms of the information carried on the disc being related simply to the contents of the disc it will be appreciated that additional information may be included. This may comprise information controlling grahics on the visual display unit 14 when in a standby mode. for example attract messages or displays bringing to the attention of the users the presence of a particular disc in the juke box. Alternatively, general colour displays may be shown. It is also possible to carry data that will effect masking or special presentation on the visual display unit 14 of a video output that may be carried on a disc.

It will understood that the drawing simply shows one example of the way in which the machine-readable information may be carried by the disc. When the information tracks are circular there may be any appropriate number from one upwards, each with its associated reading head. The data on each of those tracks may be optically readable, either in bar code form as shown or in any other form. Alternatively it may be magnetically or capacitively readable, in which case the heads will be magnetic or capacitive heads. Rather than provide the information on circular tracks it may be provided on a spiral track, or parallel spiral tracks, spiralling inwardly towards the centre of the disc. This will require that the reading head or heads be capable of tracking radially inwardly over the disc surface, and appropriate drive means for this purpose will be provided.

Claims (13)

1. A disc from which an audio and/or video work may be reproduced, the disc ' having å playing surface and an opposite surface and carrying information in machinereadable form on the opposite surface.

2. A disc according to claim 1 in which the information is magnetically coded.

3. A disc according to claim 1 or claim 2 in which the information is optically coded.

4. a disc according to any one of the preceding claims in which the information is contained in one or more circular tracks concentric with the disc.

5. A disc according to any one of claims 1 to 4 in which the information is contained in one or more tracks spiralling inwardly towards the centre of the disc.

6. a disc according to any one of the preceding claims in which the information comprises details of the disc and of individual tracks thereon.

7. Apparatus for reproducing an audio and/or video work from a disc having that work recorded on a playing surface thereof, comprising first reading means for reading the playing surface, means for processing a signal from the first reading means to produce a required output, and a second reading means for reading machine-readable information from a surface of the disc opposite to the playing surface, and for producing an information signal.

8. Apparatus according to claim 7 in which the reading means comprises a magnetic or optical reading head.

9. Apparatus according to claim 7 or claim 8 in which the reading means comprises a plurality of reading heads, each mounted at a separate fixed location and each location being a different radial distance from the axis of rotation of drive means for the disc.

10. Apparatus according to claim 7 or claim 8 in which the reading means comprises a reading head and means for tracking the reading head across the surface of the disc.

11. Apparatus according to any one of claims 7 to 10 and including display means and means responsive to the information signal for providing a display on the display means.

12. Apparatus according to any one of claims 7 to 11 and including a memory store and means responsive to the information signal to read the information carried thereby into the memory store.

13. Apparatus according to claim 12 in the form of a juke box, and including work display means and work selection means, the work display means being operatively connected to the memory store to display details of available works that have been read into the memory store from the opposite surface of the disc.