AU2005202139B2 - Secure optical disc - Google Patents

Description

AUSTRALIA

Patents Act 1990 MATTHEW J HALL, ROBERT J HALL COMPLETE SPECIFICATION STANDARD PATENT Invention Title: Secure optical disc The following statement is a full description of this invention including the best method of performing it known to us:- Title Secure Optical Disc Technical Field The present invention concerns optical discs, such as CDs and DVDs. In particular, the present invention concerns an optical disc that can be secured.

Background Art Optical discs, such as CDs (compact disc) or DVDs (digital versatile disc), are discs that are able to accept and retain information in the form of pits in a recorded layer that can be read by an optical beam. The information can include software, audio and visual information.

Optical discs are secured within a retail or rental establishment using security packaging that aims to prevent the disc from being removed until the package has been unlocked by some means. This method is largely unsuccessful at preventing theft as the packages, being generally plastic, can be tampered with or destroyed so that the disc can be removed.

Summary of the Invention In a first aspect, the invention provides an optical storage disc having a clamping area and a data area, wherein the clamping area carries a substantially flat toroidal transponder that is fabricated using MEMS (micro-electro-mechanical systems) technology and can be used as part of an identification and/or detection system, wherein the transponder is able to respond to an excitation signal in order to identify and/or detect the disc.

It is an advantage of the invention that the transponder is carried by the disc rather than by the disc's packaging that can be tampered with. It is yet a further advantage of the invention that the placement of the transponder in the clamping area does not effect the storage capacity and reading of the disc. As the clamping area is in the centre of disc, it is a further advantage that as the disc is rotated in use, the transponder experiences less radial velocity than the outer areas of the disc. This helps to reduce any impact that the transponder may have on the playability or readability of the optical disc during rotation/spinning of the optical disc.

The transponder may be carried on the external surface of the clamping area by the use of an adhesive material. The adhesive material may be permanent. The adhesive material may be substantially toroidal, such as a toroidal shaped sticker. The transponder may be integral with the adhesive material or may be secured between the adhesive material and the external surface of the disc.

The substantially toroidal adhesive material may be sized smaller than the clamping area of the disc. This allows for misalignment during the application of the adhesive material.

It is an advantage of the invention that by carrying the transponder on the external surface of the disc, the transponder can be attached to the disc postmanufacture.

Alternatively, the transponder can be glued to external surface of the carrier.

The transponder may comprise an antenna (coil) and a passive chip that includes non-volatile memory. Information stored in the non-volatile memory may uniquely identify the disc.

The system may an RFID system. The system may be a point of sale equipment or an information management system.

The transponder may be substantially balanced and symmetrical. A balanced and symmetrical transponder helps to not unbalance the disc that would otherwise adversely effect the rotation of the disc in use.

The transponder may be any one or more of the memory devices described in PCT/AU2004/0003222 (WO 2004/084131). For example, the memory device may be fabricated using MEMS (micro-electro-mechanical systems) technology. It is an advantage that the MEMS device is smaller than a RFID transponder. As a result the MEMS transponder will have little if any effect on the performance of the disc such as balance during high rotation speeds.

By using this memory device, the device is less sensitive to tampering and is more difficult to copy or emulate than transponders of conventional systems.

Further, this memory device can also receive additional information from the system that is stored by the transponder. In this way the memory device can store a running sheet of all information stored providing accountability features.

The transponder may be able to respond to multiple excitation signals provided from the system, where each of the multiple excitation signals is from a different frequency. In this way, one transponder can be used by multiple establishments which will help to keep the manufacture and distribution costs of the transponder down. This will also make the invention more attractive to organisations such as retailers as they can each adopt a different frequency when using the transponder. Further, as item identification numbers can be repeated on different frequencies, the size of the item identification number does not become unattractively large.

The system may include a reader connected to an antenna used to transmit the excitation signal to the transponder and to receive a signal from the transponder. The signal may be any signal or combination of signals that can trigger the transponder, such as a microwave.

The optical storage disc may be a CD or DVD (pre-recorded or recordable format). The clamping area can be the inner annulus of the disc, and the data area (or otherwise known as the content area) can be the annulus outside clamping area.

The transponder may be positioned completely within the normal boundary of the disc, such as moulded within the disc. It is an advantage of at least one embodiment of the present invention that the transponder is enclosed by the substrates of the optical disc, therefore making the transponder difficult to remove without damaging the disc.

The disc may comprise two substrates, wherein the transponder is contained within a first substrate. Optionally, the transponder may be enclosed within a protrusion area of the first substrate, a second substrate having a recessed area that is complementary with the protrusion area when the substrates are bonded together.

Alternatively, the disc may comprise two substrates, wherein the transponder is located within a recess of a first substrate, such that the two substrates are bonded together to close the recess. A second substrate may also have a corresponding recess, and the transponder is located within both recesses when bonded together.

In a second aspect, the invention provides a method of manufacturing a DVD optical disc described above and further comprising two substrates bonded together, the method comprising the steps of: moulding a recess into the clamping area of a first substrate of the DVD; placing the transponder into the recess; and bonding a second substrate onto the first substrate so as to close the recess.

Optionally, a corresponding recess may be moulded into the second substrate such that the two substrates are asymmetrical.

The method may further comprise the step of entering or programming data into non-volatile memory associated with the transponder.

In a third aspect, the invention provides a method of manufacturing a disc substrate for use as an optical disc as described above, the method comprising the steps of: moulding the disc substrate so that the transponder is located in and enclosed by the clamping area of the disc substrate.

Where the disc is a DVD having two disc substrates, the method may comprise moulding a first disc substrate so that the transponder is enclosed within a protrusion area of the first optical disc substrate, and moulding a recessed area into the second disc substrate such that when the substrates are bonded together the recessed area is complementary with the protrusion area.

In a fourth aspect, the invention provides a method of identifying and/or tracking an optical disc as described above, the method comprising: a reader transmitting an excitation signal; the transponder of the optical disc receiving the transmitted excitation signal causing the transponder to excite; the transponder transmitting a response signal; and the reader detecting the response signal to determine the location and/or identity of the CD or DVD.

In a fifth aspect, the invention provides a system for identifying and/or tracking an optical disc, the system comprising: an optical disc as described above; and a reader to transmit the excitation signal to the transponder and to receive the response signal from the transponder.

The response signal may include information stored in non-volatile memory associated with the transponder that identifies the optical disc. The reader may be 00 positioned in a specific location such that the transponder only receives the transmitted radio frequency by the reader when the optical disc is a specific distance from the reader location. The system can then be used to track the secured optical disc within a Sparticular boundary, such as a secure building or a retail environment. The system may further comprise an alarm that activates when the reply radio frequency signal is received by the reader.

The transponder may include non-volatile memory wherein information stored in the memory is sent with the reply radio signal and detected by the reader to identify N the optical disc carrying the transponder. The system may further comprise means for entering or programming data into the non-volatile memory of the transponder, if not already done.

Brief Description of Drawings An example of the invention will now be described with reference to the accompanying drawings, in which: Fig. 1 is a schematic view of a CD or DVD carrying the transponder; Fig. 2 is a cross-sectional view of the CD or DVD through line A-A; Fig. 3(a) and 3(b) are a side view of a first embodiment showing the application of the transponder; Fig. 4 is a schematic view of a CD or DVD carrying adhesive material; Fig. 5 is a cross-sectional view of a clamping area of a DVD through line A-A, having a transponder moulded therein; Fig. 6 is a cross-sectional view of a clamping area of a DVD through line A-A, having a transponder moulded therein; Fig. 7 shows an alternate arrangement of the transponder and DVD shown in Fig. Fig. 8 is a cross-sectional view of a clamping area of a DVD through the line A- A, having a transponder inserted after moulding; Fig. 9 shows an alternate arrangement of the transponder and DVD shown in Fig. 8; Fig. 10 shows a further alternate arrangement of the transponder and DVD shown in Fig. 8; 7 Fig. 11 a 11 c shows the assembly process of a transponder and DVD as shown in Figs. 6 to 10; and 00Fig. 10 shows a schematic view of a system using the optical discs of the present 00 invention.

It is to be noted that the proportions and sizes of features shown in the drawings Sare merely illustrative, and in some cases exaggerated to better show the features of the Sdrawings.

Best Mode for Carrying Out the Invention (In reference to Fig. 1, the optical disc 10 can be either a CD or DVD that can be either pre-recorded or recordable. The disc 10 has a data area 12 and a clamping area 14. The data area 12 is an outer annulus that contains the recorded information, such as descriptors, path tables and files. The clamping area 14 is the inner annulus having no information stored on it. In use, a clamping force is applied within the clamping area 14 by a clamping device of an optical disc reader in order to transfer movement imparted by a motor to rotate the disc 10. As shown also shown in Fig. 2, the clamping area annulus 14 is defined by radii Ra and Rb. The optical disc 10 has a top surface 18 and a bottom surface A flat toroidal shaped transponder 16 is carried by and covers most of the clamping area 14. The transponder 16 is associated with an antenna coil and a silicon chip that includes basic modulation circuitry and non-volatile memory. The transponder 16 can be energized by an electromagnetic radio frequency wave, called a carrier signal. An alternative transponder that is fabricated from MEMS technology and also includes non-volatile memory can also be used. Details of this memory device can be found in PCT/AU2004/0003222 (WO 2004/084131).

The transponder 16 can be attached to the external surface of the clamping area 14, preferably on the top external surface 18. The transponder can be attached by gluing the transponder to the clamping area, such that the transponder is covered by the glue material.

8 tt s Alternatively, the transponder can be attached to the clamping area using a ttoroidal shaped piece of adhesive flat material, such as plastic tape, label or sticker.

00 The tape captures the transponder between the tape and the top surface 18 of the clamping area 14. The adhesive material, once applied, may not be removed easily, for example it may permanently adhere to the clamping area 14. Further, the transponder Smay be integral with the adhesive material, in that the transponder cannot be separated from the adhesive material without damaging the transponder.

The method of application is shown in Fig. 3(a) and The toroidal adhesive material is sized slightly smaller than the clamping area of the disc. This is best shown in Fig. 4 where it can be seen that the inner radius of the adhesive material 16 is slightly C' larger than Ra, and the outer radius of the adhesive material 16 is slightly smaller than Rb. In this way, the adhesive material is sized to allow for slight misalignments during the attachment of the adhesive material to the clamping area.

Alternatively, the transponder 16 can be moulded into the clamping area 14 of an optical disc, such that removing the transponder 16 would require breaking the plastic of the disc. This increases the security of the optical disc For example, Fig. 3 shows the cross section of a CD along a portion of the line A-A. The CD is a polycarbonate (plastic) data/content carrying substrate carrying substrate 30, which includes a stacking ring 32 (which can be positioned on the top 18 or bottom 20 surface of the CD). The CD also includes a reflective layer 34 and a protective layer 36. During moulding of the substrate 30, the transponder 16 can be introduced anywhere within the clamping area 14 and anywhere within the thickness 38 of the substrate As shown in Fig. 6, a DVD consists of more than one substrate. The transponder 16 can be moulded into either of the two substrates. The DVD has an upper substrate 40 and a lower substrate 42 both having an area for storing data, content or recordable track (not shown). Between layers 40 and 42 there is an adhesive layer 44, such as a bonding glue. The transponder 16 can be positioned anywhere within the clamping area 14 and anywhere within the width of the substrate 46. The transponder 16 is illustrated as being positioned within the upper substrate 40, but alternatively could be positioned within the lower substrate 42.

t 9 The width 46 of the substrate 40 could vary within the clamping area 14 so as to surround the transponder 16 with more plastic. As shown in Fig. 7, the width 50 of the 00 upper substrate 40 is larger that the width 51 of the lower substrate 42 in the clamping area. This results in a protrusion extending downwards from the upper substrate To ensure that the width of the DVD remains constant, a complementary recess is created into the lower substrate 42. The protrusion need not extend the whole length between radii Ra and Rb. While the transponder is illustrated as being positioned in the upper substrate 40, alternatively it could be positioned in the lower substrate 42, in which case the lower substrate would bear the protrusion in the clamping area 14, and a recess would be created in the upper substrate Fig. 8 shows a DVD having a transponder 16 that has been inserted into the substrate 42 after the substrates 40 and 42 have been moulded. A recess 60 is moulded into or etched from the substrate 42 after moulding. The recess 60 is positioned anywhere between the radii Ra and Rb and must be at least large enough to accommodate the transponder 16. Fig. 6 shows the recess being adjacent to the centre aperture of the DVD (defined by Ra).

As shown in Fig. 9, alternatively, the recess 60 could be moulded into or etched from substrate 40. Further, the transponder 16 is located midway between radii Ra and Rb.

Fig. 10 shows a further alternate arrangement of the transponder 16 and DVD where a recess 80 is moulded or etched from both substrates 40 and 42, so that they are symmetrical. The transponder 16 is then positioned so that it sits partway into both recesses 80. Again, the recesses 80 could be positioned anywhere between radii R and Rb.

The DVDs shown in Figs. 6 to 8 can be assembled using the process shown in Figs. 1 a 1 b. Fig. 1 a shows substrate 42 having an etched or moulded recess located between radii Ra and Rb. Alternatively, recess 60 could be located in substrate or in both substrates 40 and 42 as shown in Fig. 10. The transponder 16 is prepositioned between substrates 40 and 42. As shown in Fig. 1 lb, the transponder 16 is then positioned within the recess 60. The two substrates 40 and 42 are then bonded 44 together.

In use, the transponder 16 is part of a system that is able to provide an excitation signal. For example, for a transponder fabricated using MEMS technology, the resonant members of the memory device vibrate in response to an applied excitation 00 Ssignal. This system is shown in Fig. 12. The system includes a reader 90, such as contactless read/write station unit that is connected to an antenna. The reader 0communicates with the transponder by transmitting the excitation signal and receiving a response signal from the transponder 16.

(,i Once the transponder 16 receives the excitation signal, this causes the N information that is stored on the transponder 16 to be transmitted back to the reader in response. This information could be a unique number that uniquely identifies the disc or the type of disc such as the movie title. The information may include all information that has been stored on the transponder.

The reader 90 then receives the returned signal. For example, once a response signal is detected by the reader 90, the reader 90 may then sound an alarm, allow the optical disc to be tracked, or the return signal could be communicated to a computer system 92 for processing.

The reader 90 may operate to send excitation signals on one or more frequencies that the transponder 16 is able to respond to.

For example, in a CD or DVD rental or retail establishment, the reader 90 could be placed near the doorway and the CDs or DVDs would each have a transponder carried in the clamping area. If a person tries to exit the doorway with such a CD or DVD, the transponder would receive the carrier signal from the reader and send back a return signal. Upon receiving the return signal, the reader 90 could then cause an alarm to sound that would indicate to the store owner that a CD or DVD is wrongfully being removed from the retail or rental environment. This system could also be used to ensure that optical discs having sensitive information recorded on them did not leave their secure environment, such as a building.

Alternatively, information that uniquely identifies the transponder could be written to memory associated with the transponder. For example, this could be used as part of an inventory system. To take account of all the stock, the reader 90 could send out a carrier signal and it would then receive a return signal that includes the unique identifier of each optical disc. This can then be communicated to the computer system 92 to be used in stock take processing. This system can also be used to determine whether a particular optical disc is in fact present, such as a stock item that cannot be located.

C 11 It will be appreciated by persons skilled in the art that numerous variations Sand/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly oO Sdescribed.

For example, the transponder may not be comprised of an antenna and a silicon chip. It may be of any form that is able to be used as part of a RFID system to identify and/or detect the associated disc.

SThe present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims (34)

1. An optical storage disc having a clamping area and a data area, wherein the clamping area carries a substantially flat toroidal transponder that is fabricated using MEMS (micro-electro-mechanical systems) technology and can be used as part of an identification and/or detection system, wherein the transponder is able to respond to an excitation signal in order to identify and/or detect the disc.

2. An optical storage disc according to claim 1, wherein the transponder is positioned completely within the normal boundary of the disc.

3. An optical storage disc according to claim 1 or 2, wherein the disc comprises two substrates, wherein the transponder is contained within a first substrate.

4. An optical storage disc according to claim 3, wherein the transponder is enclosed within a protrusion area of the first substrate, a second substrate having a recessed area that is complementary with the protrusion area when the substrates are bonded together.

5. An optical storage disc according to claim 2, wherein the disc comprises two substrates, wherein the transponder is located within a recess of a first substrate, such that the two substrates are bonded together to close the recess.

6. A method of manufacturing a disc substrate for use as an optical disc according to claims 1 or 2, the method comprising moulding the disc substrate so that the transponder is located in and enclosed by the clamping area of the disc substrate.

7. An optical storage disc according to claim 1, wherein the transponder is carried on the external surface of the clamping area.

8. An optical storage disc according to claim 7, wherein the transponder is carried on the external surface of the clamping area by the use of an adhesive material.

9. An optical storage disc according to claim 7 or 8, wherein the adhesive material is substantially toroidal, such as a toroidal shaped sticker.

An optical storage disc according to claim 8 or 9, wherein the transponder is integral with the adhesive material.

11. An optical storage disc according to claim 7, 8 or 9, wherein the transponder is secured between the adhesive material and the external surface of the clamping area.

12. An optical storage disc according to claim 8, 9, 10, 11 or 12 wherein the substantially toroidal adhesive material is sized smaller than the clamping area of the disc.

13. An optical storage disc according to any one of claims 7 to 12, wherein the adhesive material may be a permanent adhesive.

14. An optical storage disc according to any one of the preceding claims, wherein the transponder comprises an antenna and a passive chip that includes non-volatile memory.

An optical storage disc according to claim 14, wherein information is stored in the non-volatile memory that uniquely identify the disc.

16. An optical storage disc according to any one the preceding claims, wherein the excitation signal and the response to the excitation signal are radio frequency signals.

17. An optical storage disc according to any one of the preceding claims, wherein the transponder is substantially balanced and symmetrical.

18. An optical storage disc according to claim 14, wherein the non-volatile memory can receive information from the system and store it.

19. An optical storage disc according to any one of the preceding claims, wherein the transponder is able to respond to multiple excitation signals provided from the system, where each of the multiple excitation signals is a different frequency.

An optical storage disc according to any one of the preceding claims, wherein the system includes a reader connected to an antenna used to transmit the excitation signal to the transponder and to receive a response signal from the transponder.

21. An optical storage disc according to any one of the preceding claims, wherein the optical storage disc is a CD or DVD (pre-recorded or recordable format).

22. A method of manufacturing an optical storage disc according to claim 5 wherein the disc is a DVD further comprising two substrates bonded together, the method comprising the steps of: moulding a recess into the clamping area of a first substrate of the DVD; placing the transponder into the recess; and bonding a second substrate onto the first substrate so as to close the recess.

23. A method of manufacturing an optical storage disc according to claim 22, wherein the method further comprises the step of entering or programming data into non-volatile memory associated with the transponder.

24. A method of manufacturing a disc substrate according to claim 4, where the disc is a DVD having two disc substrates and the method further comprises moulding a first disc substrate so that the transponder is enclosed within a protrusion area of the clamping area of the first optical disc substrate, and moulding a recessed area into the second disc substrate such that when the substrates are bonded together the recessed area is complementary with the protrusion area.

A method of identifying and/or tracking an optical disc according to any one of claims 1 to 21, the method comprising: a reader transmitting an excitation signal; the transponder of the optical disc receiving the transmitted excitation signal causing the transponder to excite; the transponder transmitting a response signal; and the reader detecting the response signal to determine the location and/or identity of the optical disc.

26. A system for identifying and/or tracking an optical disc, the system comprising: an optical disc according to any one of claims 1 to 21, and a reader to transmit the excitation signal to the transponder and to receive a response signal from the transponder.

27. A system according to claim 26, wherein the response signal includes information stored in non-volatile memory associated with the transponder that identifies the optical disc.

28. A system according to claim 26 or 27, wherein the reader is positioned in a specific location such that the transponder only receives the transmitted excitation signal when the optical disc is a specific distance from the reader location.

29. A system according to claim 27, wherein the system further comprises means for entering or programming data into the non-volatile memory of the transponder.

A system according to any one of claims 26 to 29, wherein the system is a point of sale equipment or an information management system.

31. An optical storage disc according to claim 1 as substantially as herein described, with reference to the accompanying Figs. 1 and 2, and any one of Figs. 3 4, Fig. Fig. 6, Fig. 7, Fig. 8, Fig. 9, Fig. 10, or Fig. 11.

32. A method of manufacturing an optical disc according to claim 6 as substantially as herein described with reference to Fig. 5 or Fig. 6.

33. A method of manufacturing an optical disc according to claim 22 as substantially as herein described with reference to any one of Figs. 8 to 11.

34. A method of manufacturing an optical disc according to claim 24 substantially as herein described with reference to Fig. 7. A system according to claim 26 as substantially herein described with reference to Fig. 12. Dated this eleventh day of May 2006 Matthew J Hall, Robert J Hall Patent Attorneys for the Applicant: F B RICE CO