WO1990011600A1

WO1990011600A1 - A process facilitating the continuous playing of both sides of a disc without any interruption which can be detected by the user at the end of side 1, constant linear and/or angular speed, and a device applying said process

Info

Publication number: WO1990011600A1
Application number: PCT/FR1989/000126
Authority: WO
Inventors: Jean-Claude Bernardo
Original assignee: Bernardo Jean Claude
Priority date: 1987-09-29
Filing date: 1989-03-21
Publication date: 1990-10-04
Also published as: FR2621160A1; EP0415940A1; FR2621160B1

Abstract

The invention is a process which, in three stages, finally facilitates the continuous playing of both sides of a disc without any interruption which can be detected by the user at the end of side 1, constant linear and/or angular speed. In the first stage the prepared matrix permits the recording of side 1 from the outer edge to the centre and of side 2 from the centre to the outer edge. In the second stage, the disc provides programme continuity at its centres. In the third stage, the player adopts a device which is added to the alignment mirror (4) and the lens (5) and which, via a mirror (8), on starting actuated by the player, redirects the optical beam towards a mirror (9), and alignment mirror (10) and a lens (11) for access to the other side of the disc. Application: discs read by an optical beam. Extension intended to two discs. Variations.

Description

Method for continuous reading of the two sides of a disc without perceptible interruption by the user at the end of side 1, constant linear speed and / or constant angular speed, and device applying said method.

The present process by three phases which are the modification of at least one matrix used for pressing and / or recording of the two sides of a disc then the production consequently of a disc called hereinafter produced disc and finally by at least an additional reading device on a reader corresponding to the type of disc will allow the complete reading of the program recorded on the two sides of the disc produced without intermediate interruption perceptible by the user at the end of the first side.

The various types of discs in use currently used for recording and reproducing sounds, images, computer data, or combining several of these possibilities, have in common a spiral groove or an information spiral whose meaning is invariable because universally adopted: disc seen from above face 1 (FIG.1) and disc seen from above face 2 (FIG.2). A disc recorded on each side which has an inner edge (FIG.3 (A)) and an outer edge (FIG.3 (B)). A disc has its two sides recorded in the same way: from the outer edge to the inner edge (FIG. 4 (B to A)), for example a microgroove disc also called 33rpm, or from the inner edge to the outer edge (FIG. 5 (A to B)) such as a commercial video disc. Consequently and in fact, the two sides of a current disc are read in the same direction: from the outside edge to the inside edge (FIG. 4 (B to A)) as for the 33turn disc, from the inside edge to the edge outside (FIG.5 (Obverse B)) as for the video disc.

The process intervenes to overcome a major drawback.

Currently a disc can not have its two sides read without perceptible interruption for its user at the end of side 1, This is not very restrictive in the case of the disc 33tourε for example or discs of its type known as slow rotation speed, manual operation turning the disc approximately corresponding to the time of silence between two recorded songs; disc turn arms or other methods are not faster and (Contd. on page 2) sometimes require a reversal of the direction of rotation of the disc possible only by the slow speed of the motor.

But the era of discs rotating at high speed has arrived for the general public with compact disc, audio and / or video disc, and video disc for which the waiting time to stop rotation of said disc at the end of side I for the return and the time it takes to reach the rotation speed necessary to resume reading at the start of side 2 can be considered an unpleasant constraint, especially in the case of a video program because it significantly interrupts the atmosphere or the rhythm of said program.

The application to these discs specifically of the process corresponds to a real need of the general public and eliminates towards this type of disc a restraint that the general public still considers that a videotape has its recorded program played in full without interruption.

The characteristics and advantages of the process which innovates in the field of the disc will therefore be explained by taking specifically for example the audio and / or video discs read by optical beam (one or more). It is essential to know that there are two types of recording and reading in this range: at constant linear speed called CLV and at constant angular speed called CAV. The reader identifies the type of disc to be read (CLV or CAV) thanks to part of the information concerning it (the reader) recorded at the beginning and / or end of each side of the disc. For this reason the reader when it starts up must be able to have access to this information before accessing the recorded work and this is done in a place on the disc where it will be at an equal speed of rotation for CLV or CAV: the inner edge of the face offered for reading (FIG. 3 (A)) In fact, according to its principle of recording and reading a CLV disc decreases its speed of rotation as the reading optical beam approaches from its outer edge (FIG. 3 (B)). All CLV or CAV discs are currently recorded and read from their inner edge (FIG.5 (A)) to their outer edge (FIG.5 (B)) and the players stop at the end of each side by putting themselves out function Finally, according to a simplified diagram (FIG. 6) the video disc (I) currently marketed is read from below by an optical beam emitted for example by a laser (2) which passes (said beam) through a beam splitter or a photo diode for example (3) is reflected by an alignment mirror (4) passes through an objective lens (5) is reflected by the information spiral recorded on the disc which returns the signal carrying the illuminated information through the objective lens (5) the alignment mirror (4) the beam splitter (3) directly or not towards a demodulator (6), a motor (7) ensuring the correct rotation of the disc. This simplified route represents the current reading by a reader. (F0) is the beam.

PROCESS

The process respects the groove (or universally adopted informational spiral for each recorded side, side I (FIG.1), side 2 (FIG.2), which guides the reading mode (the optical beam). applies equally to a disc recorded for playback of the two sides of CLV or of the two sides of CAV or of one side of CLV and one side of CAV or of one side of CAV and one side of CLV.

First step of the process: currently the preparation of one (or more) pressing and / or recording matrix offers the start of recording for side I (FIG. 7) from the inner edge to the outer edge (FIG. 7 ( A to B)) and the continuation of the recording for side 2 (FIG.8) also from the inside edge to the outside edge (FIG.8 (A to B)).

the matrix (or more) according to the method offers the start of recording for side I (FIG.9) from the outside edge to the inside edge (FIG.9 (A to B)) and the rest of the recording for side 2 (FIG.10) from the inside edge to the outside edge (FIG.10 (C to D)). The disc it produces is the second step in the process.

Second step of the process: the disc produced according to the process therefore now has a reading direction (FIG. II (I and 2) going side I from the outside edge (FIG.11 (A)) to the inside edge (FIG.11 ( B)) and side 2 going from the inside edge (FIG. 11 (C) towards the outer edge (FIG. 11 (D)).

The current information intended for the player prior to playing a normal disc is CLV or CAV identification, chapter or song numbers, CAV image numbers, time elapsed since the start of the program, etc. They appear on the inside edge of the normal disc proposed for reading (FIG. 6 (A)) before the start of the program and are read as explained above at identical speed whether the disc is CAV or CLV.

The disc produced according to the method adopts the same positioning of this information for reading by the reader. The difference is that the current disc offers this information at the beginning of side I or 2 offered for reading (FIG. 6 (A)) and that 'they only concern said face, whereas the disc produced according to the method offers this information at the start of side 2 (FIG.11 (C)) for identification as a produced disc (FIG.12 (C)) that they relate to its two faces and therefore contain indication (s) for the use by the reader of the reading device according to the method to achieve the purpose of the method which is the continuous reading of the two faces without perceptible interruption by the user.

The disc produced according to the method also includes information s) for the player used to indicate the beginning or the end of the program recorded on each side.

Third step of the process: the reader according to the process requires a device allowing the positioning at the start of side 2 of the optical beam when the reading of side I ends in order to ensure the reading of the program in continuity according to the purpose of the process.

One of the most simplified examples of this device (FIG. 12) shows a mirror (8) a mirror (9) an alignment mirror (10) and an objective lens (11) out of service during the reading of the information intended to the reader (FIG. 12 (C)).

A) if the disc is normal, the commissioning of the device according to the method is not requested and the reader will read the side offered for reading normally as in FIG. 6 by moving the mirror 4 and the lens 5 from the inner edge A to the outer edge B with stopping the reader at the end of reading.

B) if it is a disc produced according to the process, the reader therefore reads the information concerning it (FIG. 12 (C)) and then immobilizes on the signal of the produced disc announcing the start of the program on its side (which is therefore the face 2) (FIG.12 (C)) the mirror 4 and the lens 5.The reader activates the device (FIG.13) by simply raising the mirror 8 which consequently directs the optical beam towards the mirror 9 the alignment mirror 10 and the lens II on the outer edge A of the produced disc, the beam meeting there the signal of the produced disc announcing the start of program of side I. A pause of the optical beam on this signal gives the reader time in the case of a side I indicated in the information (FIG. 12 (C)) as being in CLV to reduce its reading speed accordingly

The reader reads side I (FIG.13) from the outer edge A towards the inner edge B and its optical beam (FIG.14) meeting the signal of the disc produced at the end of side I at this point B the reader immobilizes its mirror 10 and its lens II on this signal and (FIG.15) by the deactivation of the mirror 8 resumes by its optical beam, the reading of the face 2 from the inner edge C towards the outer edge D thanks to the mirror 4 and to the lens 5 immobilized on standby under the program start signal on side 2 (FIG.I2 and I3 (4 and

The reader thanks to the modification of the matrix (1st stage) to the disc produced by said matrix (2nd stage) was therefore able to read thanks to the device (3rd stage) the two sides of the disc produced in continuity.

The matrix (FIG.9 side I and FIG.10 side 2) allowed the program of the produced disc (FIG.11) to continue at its internal edges B and C, and this is thanks to: A) the reference signals on the disc produced at the end of side I (FIG.14 (B)) and at the start of side 2 (FIG.15 (C) B) at the same speed as the CLV or CAV or CLV / CAV sides at these locations (FIG. 14 and 15), C) to the device 8, 9, 10, 11, that the reader according to the method allows continuous reading of the two sides of the program.

Details: the activation / deactivation of the mirror 8 (FIG. 12,13,14,15) can be done for an audio program (if we want) during a "blank" program, but the fact that it occurs between two images of a video program is not perceptible to the user: a video image (the video is recorded and played at approximately 25 images / second) is read in 4 / 100ths of a second and a mirror (eg from a reflex camera) moves up to l / 2000th of a second.

The immobilized mirrors and lenses (FIG.13 (4 and 5) FIG.15 (10 and II)) allow the return of the optical beam for the controlled search of a piece or chapter or image or other by the 3 ector and the user.

The possible time for the CLV speed to be adopted by the reader in position (FIG. 13 (A)) is negligible for the user as it intervenes before reading said program.

The process described as above requires neither interruption of reading of the disc at the end of the face, nor modification of the groove or spiral of information adopted universally, nor intervention of the user during reading, and adapts to CLV discs , CAV, and CLV / CAV.

The reader at the end of side 2 (FIG. 15 (D)) encounters the information at the end of the program for deactivation.

EXTENSION OF THE PROCESS

Some programs due to their duration or recording mode (CLV or CAV) are offered distributed over two discs. The method can be applied to a player capable of receiving two discs produced according to the method.

First step of the process, second disc produced by the program. The matrix according to the method offers the start of recording for side 3 of the program (FIG. 16) from the outside edge to the inside edge (FIG. 16 (E to F)) and the possible continuation of the recording for the side 4 of the program (FIG.17) from the inside edge to the outside edge (FIG.17 (G to H)).

Second step of the process, second disc produced by the program. The second disc produced according to the process therefore now has a reading direction (FIG.18 (3 and 4)) going to face 3 from the outer edge (FIG.18 (E)) towards the inner edge (FIG. 18. (F) ) and side 4 going from the inside edge (FIG.18 (G)) to the outside edge (FIG.18 (H)). Information about the two produced discs ddr program are always positioned at the beginning of side 2 (FIG.12 (C)) for the whole program and concern the four sides. The second disc produced according to the method also includes information (s) for the player used to indicate the beginning or the end of the program recorded on each side.

Third step of the process, second produced disc of the program. The reader can, if he wishes, use the same motor for the synchronization of rotation of the two produced discs of the program. These may or may not be separated by a wall depending on the reader. (s) is the second disc.

The reader according to the method requires an additional device allowing the positioning at the start of side 3 then possible side 4 of the optical beam when the reading of side 2 ends in order to ensure the reading of the program in continuity according to the purpose of the process.

One of the most simplified examples of this device (FIG. 19) shows the first disc of the program at the end of reading of its side 2 with out of service the new additional device consisting of a mirror 12 of an alignment mirror 13 of a lens 14 of a mirror 15 of an alignment mirror 16 and of a lens 17.

The reader therefore (FIG. 19) at the end of side 2 of the first disc produced by the program encounters the end of side 2 signal at point D and immobilizes on this signal its alignment mirror 4 and its lens 5, and (FIG .20) by switching off the mirror 9 and putting the mirror into service 6 consequently directs its optical beam towards the mirror 12 the alignment mirror 13 and the lens 14 on the outer edge E of the second produced disc which is side 3. The beam finds there the signal to start recording and continues reading the program towards the inner edge F (FIG.21).

At the end of face 3 with the edge F reached (FIG. 22) the end of recording signal immobilizes the alignment mirror 13 and the lens 14, and the commissioning by the reader of the mirror 15 makes it possible to orient accordingly the optical beam towards the alignment mirror 16 and the lens 17 at the inner edge G of the face 4 for reading. The reader will be deactivated with the end of program information at the outer edge H of side 4 of the program.

The continuity of reading of the two discs produced according to the method (Steps1, 2,3) is illustrated in continuity by FIGURES 12,13,14,15,19,20,21,52.

It is desirable that for a program of two discs produced the faces 2 and 3 are of the same nature (CLV or CAV) to avoid an adjustment of speed of the reader which can be more or less fast according to the readers and to hinder the continuity of the program.

It is also obvious that in the explanatory figures the simplification was not pushed to the maximum for the good understanding of the process: one can thus reduce to a single mirror the mirrors 9 and I5 "as well as the alignment mirrors 10 and 16 which could only be rotatable, etc.

On a program of two produced discs, the method allows the continuous reading of four CLV sides, or four CAV sides, or one CLV side / two CAV / one CLV, or one CAV side / two CLV / one CAV , or a CLV and three CAV, or a CAV and three CLV, and the desire for sides 2 and 3 at the same speed is not a constraint from the moment when two discs are used. The possible adaptability technique of a reader can erase this wish.

It is a very important point to emphasize again: the possibility of having a continuous CAV program on four accessible sides is extremely important in the so-called interactive use of these discs multiplying the current capacity of the general public or industrial and professional by four.

In addition to the possible simplifications of the process in reading step mentioned above, there are variations of said process.

Example of variation: this variation still respects the universally adopted meaning of the groove or information spiral on side I (FIG.I) and side 2 (FIG.2).

First step: the matrix according to the method offers the start of recording for side I of the program (FIG.23) from the inside edge to the outside edge (FIG.23 (A to B)) and the rest of the program for the side 2 (FIG. 24) from the outer edge to the inner edge (FIG. 24 (C to D)).

Second step: the disc produced according to the process therefore now has a reading direction (FIG. 25 (1 and 2)) going side I from the inside edge (A) to the outside edge (B) and side 2 from the outside edge (C ) towards the inner edge (D). Information relating to both sides and intended for the reader is always recorded in the same place (FIG. 25 (A)) The disc produced includes a signal for end of side I and a signal for start of face recording 2.

Third step of the process: the necessary device is the same as previously in the initial position FIG.12, and is reproduced FIG.26.0n note that now (FIG.26 the direction of reading A, B, C, D, has changed accordingly of the variation of the process, the first and second steps of which have just been explained. The reader therefore reads the side I offered from the inside edge A to the outside edge B, and the signal from the disc produced indicating the end of recording on this side. causes the reader to commission the mirror 8 (FIG. 27) which consequently directs the optical beam towards the mirror 9 the alignment mirror 10 and the lens II for reading the side 2 from the rest of the recording on board C.

In the case of two discs produced the device remains the same (FIG. 28) as shown by the reading of side 3 but the order of use of the various mirrors and lenses has changed as well as the change in numbering shows so to read in order the facesl, 2,3,4, in their direction A to B, C to D, E to F, G to H. This variation still allows the reading without interruption in CLV or CAV but for a disc CLV / CAV there will be 'when passing from side B. and C a need to adjust the speed to the new mode, which for a second disc in the same case will be repeated at points F and G.

The initial process therefore seems the most interesting.

There are variations on the basis of inversion of the groove or information spiral which will not be explained here.

Claims

I. Method for recording and reading a program on one or two discs read by optical beam and allowing continuous reading without end-of-face interruption noticeable by the user that these discs are at constant linear speed and or angular speed constant characterized by the matrix recording of the first face of a disc from its outer edge towards its inner edge and the second face of its inner edge towards its outer edge thus producing in the second place a disc whose program continuity exists for the same disc at its inner edges, that is to say in places where the disc is read at the same speed as it has its two faces in constant linear speed, constant angular speed, or constant linear speed / constant angular speed, by a reader adopting thirdly a reading device comprising mirrors controlled by the reader which putting them into service or out of service redirects its optical beam e so as to have successive and orderly access to the recorded faces of the disc (s) offered for reading by means of alignment mirrors and objective lenses provided for each face.

2. Reading device for implementing the method according to claim I characterized in that it includes mirrors (8, 9, 12, 15) controlled by the reader separately or not which putting them into service or out of service redirects its optical beam so as to have successive and orderly access to the recorded faces of the disc (s) according to the method offered for reading thanks to alignment mirrors (10,13,16) and objective lenses (11, 14,17) provided for each side.