WO1986005019A1

WO1986005019A1 - Circuit for the reading of a coded label

Info

Publication number: WO1986005019A1
Application number: PCT/DE1985/000159
Authority: WO
Inventors: Jürgen Rehder
Original assignee: Frank Oeser Produktion
Priority date: 1985-02-23
Filing date: 1985-05-11
Publication date: 1986-08-28
Also published as: DE3506445A1; AU4294585A; EP0213136A1

Abstract

In order to make a characteristic mark which can not be counterfeited, a coded label is stuck on the back of a video cassette. The label is subdivided in conformity with the code into surface portions which are in connection with outer receiver surfaces. After introducing a video cassette having the label into a reading apparatus, different phase signals are emitted by emitter electrodes situated at a distance from the receiver surfaces; said signals are received by the receiver electrodes arranged facing said surface portions. Each received signal is finally adjoined either to the first or to the second signal emitted and characterized by the logic states H or L. After decoding said states, is displayed on a display device the decimal figure which corresponds to the code of the label.

Description

Circuit arrangement for evaluating a coded

Etiquette

The invention relates to a circuit arrangement for evaluating a coded label, in particular for evaluating a coded label for a video cassette.

In everyday practice, as is known, there is a need to mark objects for the purpose of unambiguous identification and assignment in order to be able to effectively counter any abuses.

In this context, the video cassettes are particularly worth mentioning. are available in increasing numbers. Along with this, the commercial trade or the rental of video cassettes for payment is becoming increasingly important.

In order to prevent or effectively counter the production and marketing of so-called pirated copies of the video cassette with copyright-protected content and the improper use of such video cassettes, forgery-proof labeling or marking of the original video cassette is desirable, for which then a circuit arrangement regarding the evaluation of the characteristic - 2 -

Means of drawing is required.

A conceivable possibility now consists in sticking a label to the video cassette which identifies the respective video cassette and its content, and the invention is based on the object of creating a tamper-proof label and, above all, one Specify a circuit arrangement for evaluating a coded label in order to enable marking and detection of the relevant video cassette with simple and inexpensive means.

This object is achieved in the circuit arrangement mentioned in the preamble of claim 1 in that the label is acted upon by two different basic signals, each of which can be received along the surface of the label at predetermined local locations, and in that the signals received are compared by comparison with one of the Base signals are assigned to the first or second base signal.

The invention is based on the idea of coding the label in such a way that the local locations at which one or the other basic signal can be received to a greater or lesser extent are determined or specified by a selectable coding. By comparison an assignment to the first or second base signal of the respectively received signal with one of the two base signals can be established, ie the code of the label is read in this way. The two base signals are thus evaluated against one another, and in the manner of a discriminator it is possible to determine at a local point - at which both base signals can be received - and to determine which signal is "stronger" or more clearly to be found here, so that the received signal can be assigned to the first or second base signal.

In an expedient embodiment, the label that is essential for the invention has an electrically conductive surface with two outer receiving surfaces assigned to the transmitting electrodes, with a plurality of partial surfaces being assigned to each receiving surface in accordance with the selectable coding.

From an electrical point of view, the label - which is designed as an adhesive label in a further advantageous embodiment of the invention - can be bad

- \ th to very bad conductors, the capacity allocation is relatively low, and also large stray capacities can occur. So you can

- 4 -

relatively large dielectric losses also occur. Nevertheless, the circuit arrangement according to the invention makes it possible to clearly read the label or the coding.

The above-mentioned coding can be achieved by dividing the label, seen in the longitudinal direction, into two surfaces which are electrically insulated from one another - receiving surface with assigned partial surfaces - the insulation being formed by a specially selected meandering line. The exact formation of this line or its course forms the coding of the label.

The selection of the insulation line mentioned defines the different subareas, and as a result, when the ^" signals to be found on the subareas ^" are received, a coded assignment to the first or to the second basic signal takes place in the manner described above.

The assignment of the signals received by the individual partial areas to the first or second basic signal, ascertained with the circuit arrangement according to the invention, can be done with the two digital states Identify "1" or "0", and a decimal number which identifies the respective encoded label is possible optically via a downstream encoder and converter. If the label is stuck on the back of a video cassette, the displayed decimal number can easily be assigned to this specific video cassette or the content of the video cassette.

In an expedient embodiment of the invention, the label can be stuck on its back with a conventional paper label for the labeling of the video cassette known per se, the thickness or thickness of this paper label simultaneously being the required distance between the transmitting electrodes and creates the receiving electrodes on the one hand and the electrically conductive surface of the label on the other.

By pasting the coded label with the usual paper label, the coded label becomes invisible at the same time, which is an advantage with regard to misuse. In addition, a video cassette marked in this way is practically completely forgery-proof due to the coded label affixed by the authorized manufacturer and user. Additional security can be achieved in that, according to another advantageous development of the invention, trace elements are added to the electrically conductive surface of the label, which elements can be clearly analyzed.

Further expedient refinements of the invention are specified in the subclaims and can be found in the drawing.

The invention is explained in more detail below on the basis of the exemplary embodiment shown in the drawing. Show it:

1 shows a circuit diagram of a circuit arrangement for evaluating a coded label,

2 shows a cross-sectional view of a label used,

Fig. 3 is a perspective view of a housing in which the circuit arrangement is housed, and

- 7 -

Fig. 4 is a perspective view of a video cassette, the back of which is pasted with a coded label.

The circuit arrangement shown graphically in FIG. 1 is used for "reading" a coded label 10, which is designed in the manner of an embossing film or an embossing label and, according to FIG. 2, an electrically conductive surface 56 and a lower adhesive layer 58 owns.

The label 10 comprises an insulating line 12, the desired coding is determined by the course of which, and through which the ^• surface 56 of the label is divided into electrically isolated surface regions zwei.voneinander 10th

From an electrical point of view, it is sufficient if the label 10 represents a bad conductor and forms a bad capacitor, because the circuit arrangement described below nevertheless enables an evaluation with a clear decoding for the identification of the label 10 or a video cassette 70 (see Fig. 4), on which the label 10 is glued. Despite the low capacity allocation, and despite the fact that large stray capacities can occur and

- 8th -

that there are large dielectric losses due to the adhesive or the lower adhesive layer 58, the label can be read clearly, and the selected code permits electronic evaluation of the embossed label and the visual display of a number on a display device 54, whereby 1024 options are available.

The circuit arrangement comprises an HF generator 22 which generates two signals which are different in phase from one another. It is assumed that the two signals have the different phases 0 ₁ and 0 "and that the phase shift is 180 °.

The two AC voltage signals arrive at outer planar transmission electrodes 18 and 20, which feed outer reception areas 14 and 16 of the label 10, the reception areas 14 and 16 being located at a short distance from the transmission electrodes 18 and 20.

Depending on the coding given by the course of the isolation line 12, a row of a maximum of 10 partial areas 24 and 26 of the two receiving areas 14 and 16 are connected to one or the other receiving area 14 and 16, respectively. - 9 - ^■

A possible extreme case would be that all partial areas are connected to the receiving area 14, and another extreme case is that all partial areas are connected to the opposite receiving area 16. In the case shown in FIG. 1, some partial surfaces 24 are each connected to the receiving surface 16 and some partial surfaces 26 are connected to the receiving surface 14.

The circuit arrangement further comprises ten receiving electrodes 28, which face the subareas 24 and 26 in terms of area. The size of the receiving electrodes 28 can be approximately 0.5 cm ² , the receiving electrodes 28 being located at a distance of a few tenths to a few millimeters from the partial surfaces 24 and 26, which can be determined by the mechanical conditions.

As will be explained further below with reference to FIG. 3, the circuit arrangement is operated by a battery and accommodated in a handy housing 60, and the mechanical conditions of the housing 60 make the distances between the transmitting electrodes 18 and 20 and the receiving surfaces 14 , 16 on the one hand and between the receiving electrodes 28 and the subareas on the other hand.

- 1 0 _ ^■

The receiving electrodes 28 now each receive an alternating voltage, which is assigned to either phase 0 ₁ or 0_, in accordance with the selected coding, which defines the partial areas 24 and 26, respectively.

Each receiving electrode 28 is assigned an receiving circuit 39, i.e. The reception circuit 39 is present a total of ten times.

The AC voltage signal received by a receiving electrode 28 is amplified in a high-frequency amplifier 30 so that an evaluable level is available. From the high-frequency amplifier 30, the signal reaches the one input of an AND gate 32, the output of which leads via a diode 34 and an RC element 36, 38 to an output terminal Q ₁ .

In order to enable the received AC voltage signal to be assigned to one or the other signal of the HF generator 22 with different phases 0 ₁ and 0 ₂ , the one signal of the HF generator 22 is provided via a trimming resistor 42, which is connected to ground Capacitor 44 is connected downstream, leads to an amplifier 46. In a Schmitt trigger 48, the phase 0 ₁ signal is converted into a square-wave signal, and by a

- 1 1 -

a short scanning pulse is obtained after the mono-flop 50.

This scanning pulse arrives at the other input of the AND gate 32, so that a logic H signal or a logic L signal is present at the output of the AND gate 32 or at the output terminal Q-, depending on whether the receiving electrode 28 an alternating voltage signal of the phase from the assigned partial area 24 or 26. or φ ~ received ..

In the manner described, Q-. to Q ₁₀ generates logic signals which are fed to a decoder 52. On the downstream display device 54, a seven-segment display can then be used to display a decimal number, which is predetermined by the coding of the label 10, in a manner known per se.

One advantage of the circuit arrangement described is that by using the Schmitt trigger 48 and the monoflop 50, the scanning signal can be selected in its temporal assignment to the phase 0 ₁ and 0 signal so that all Phase shifts, which are to be regarded as constant in the first approximation, at

- 1 2 -

the transmission from the transmission electrodes 18 and 20 to the label 10 can be compensated. Larger adjustment work can therefore be dispensed with, which is of economic importance for the manufacture of the circuit arrangement.

3 shows a hand-held device with a housing 60, in which the circuit arrangement is accommodated. A battery, which is also located in the housing 60, serves as supply.

4 shows a video cassette 70 on which the coded label 10 is glued to its back 68. otherwise, which is not shown in FIG. 4, the paper label which is customary in the case of video cassettes and which is used for labeling in a manner known per se is stuck onto the label 10.

The housing 60 has a receiving opening 62 into which the video cassette 70 - with the back 68 first - can be inserted. When the video cassette 70 is inserted, a microswitch 64 is actuated, which switches on the battery for the voltage supply of the circuit arrangement. When the video cassette 70 is removed, the battery is disconnected from the circuit arrangement.

- 1 3 -

On the recording opening 62 has a rear rear wall 66, up to which the video cassette 70 can be inserted. In this position, the transmission electrodes 18 and 20 and the reception electrodes 28 are in the desired position. position at a distance from the label, which can now be "read" in the manner described above. The relevant number of the video cassette 70 is displayed on the display device 54 integrated in the housing.

The above description clarifies that handling is extremely simple since the video cassette can be easily inserted into the receiving opening 62. The label 10 allows forgery-proof identification of the video cassette 70, the identification or associated number of which can be easily ascertained using the hand-held device.

Additional security can be achieved if 10 trace elements are added to the label, which can be analyzed in the event of a dispute when the question of evidence concerns whether the video cassette in question is counterfeit or not.

It should be pointed out again on the basic idea of the invention. , which consists in carrying out a weighting of the signals received with the receiving electrodes 28. In fact, a receiving electrode 28 does not only receive a unique signal with approximately phase 0_. Rather, signal components of 0 ₂ are also received. The decisive factor is whether the received signal tends more to source ₁ or to source 0 ₂ . The assignment described with reference to FIG. 1 is then carried out according to the discriminator principle. It is surprising that the unambiguous assignment and the unambiguous reading of the label 10 is possible, even though it is a bad capacitor. This in turn makes it possible to produce the labels 10 inexpensively in large numbers.

For example, an aluminum layer can be used for the electrically conductive surface 56 of the label 10, to which analyzable trace elements are added. An inexpensive commercial adhesive can be used for the lower adhesive layer 58.

The invention is not limited to the exemplary embodiment described. Rather, the idea according to the invention can also be implemented in another form. For example, instead of the phase shift of the two signals generated by the HF generator 22, it is possible to start with two signals which have different frequencies. The different sequences can be fed in as explained with reference to FIG. 1 via the transmitting electrodes 18 and 20. The receiving electrodes 28 are then used to assign the signals to the coded partial areas 24 and 26 - either one or the other Frequency - received. Simple filters or discriminators can be used for the evaluation.

Claims

- 16-patent claims

1. Circuit arrangement for evaluating a coded label, in particular for evaluating a coded label for a video cassette, characterized in that the label (10) is acted upon by two different basic signals, each along the surface (56 ) of the label can be received at predetermined local locations (24; 26), and that the received signals are assigned to the first or second base signal by comparison with one of the base signals.

2. Circuit arrangement according to claim 1, thereby - 17 -

indicates that it has two outer transmitting electrodes (18, 20) for the different basic signals, that the label (10) has an electrically conductive surface (56) with two outer receiving surfaces (14, 16) assigned to the transmitting electrodes (18, 20) , and that each receiving surface (14, 16) is assigned a plurality of partial surfaces (24; 26).

3. Circuit arrangement according to claim 2, characterized in that the one of the receiving surfaces (14; 16) assigned partial surfaces (24; 26) are electrically isolated from the partial surfaces of the other receiving surface in accordance with a selectable coding (12).

4. Circuit arrangement according to one of the preceding claims 1-3, characterized in that the transmitting electrodes (18, 20) are at a distance from the receiving surfaces (14, 16) of the label (10), and that the partial surfaces ( 24; 26) of the label (10) are assigned receiving electrodes (28) which are arranged at a fixed distance from the partial surfaces (24; 26).

5. Circuit arrangement according to one of the preceding claims 1-4, characterized in that an RF generator (22) is provided for the generation of the base signals, and that the two base signals by 180 ° in the Phase (0 ₁ , 0 ₂ ) are shifted against each other.

6. Circuit arrangement according to claim 5, characterized ge indicates that the frequency of the base signals is 1 MHz.

7. Circuit arrangement according to one of the preceding claims 4-6, characterized in that each receiving electrode (28) is connected to the one input. One of the receiving electrode assigned AND gate, the other input of a base signal via a trigger circuit (48) downstream monoflop (50) is supplied.

8. Circuit arrangement according to claim 7, characterized in that the AND gate (32) is preceded by an RF amplifier (30).

9. Circuit arrangement according to claim 7, characterized ge indicates that the trigger circuit is a Schmitt trigger (48), which has an RC element (42; 44) and an amplifier

(46) are connected upstream.

10. Circuit arrangement according to one of the preceding claims 7-9, characterized in that the Outputs of the AND gates (32) are connected to the inputs (Q ₁ Q _1Q ) of a decoder (52).

11. Circuit arrangement according to claim 10, characterized in that the decoder (52) is an optical display device (54) for the representation of decimal numbers.

12. Circuit arrangement according to one of the preceding claims 1-11, characterized in that it is housed in a housing (60) which has a receiving opening (62) for a video cassette (70) and that the label (10 ) is glued to the back (68) of the video cassette (70).

13. Circuit arrangement according to claim 12, characterized in that in the area of the receiving opening (62) a microswitch ^' ter (64) is provided for starting up the circuit arrangement, and that the microswitch (64) when inserting the video cassette ( 70) into the receiving opening (62).

14. Circuit arrangement according to one of the preceding claims 11 to 12, characterized in that the display device (54) is integrated in a side wall of the housing (60). - 20 -

15. Circuit arrangement according to claim 12, characterized in that the label (10) is covered with a paper label for labeling the video cassette by the user.

16. Circuit arrangement according to claim 1, characterized ge indicates that the base signals have a different frequency.

17. Circuit arrangement according to claim 1 and / or 2, characterized in that the label (10) consists of a lower adhesive layer (58) and an aluminum-containing surface (56).

18. Circuit arrangement according to claim 17, characterized in that the label (10) is additionally admixed trace elements are analyzable.