EP0996099A2 - Electroluminescent semiconductor for testing luminescent security features - Google Patents

Abstract

The arrangement has ultraviolet and/or infrared electro-luminescent semiconducting solid state elements e.g. light emitting diodes (2,3) and, optionally, a light element (4) whose radiation lies in the visible band. The elements are mounted together in a housing (5) to produce a focused light beam containing both visible and non-visible components. A spring-loaded push button is operated to activate the combination of elements. An Independent claim is also included for a method of monitoring luminescent security characteristics.

Description

The present invention relates to a method and an apparatus for Verification of luminescent security features using UV and Luminescent diodes (LEDs) emitting infrared light.

Luminescent security features for the value and security area have been used for a long time. To the security features on the affected security and valuables are attached with Reliable efforts to make acceptable efforts visible have already been varied Efforts have been made to implement appropriate procedures and devices to develop.

In most cases, the objective was to check banknotes, Credit or check cards at sales outlets for the development of corresponding ones Methods and devices specified. As salesrooms or Sales outlets are looked at all conceivable places where value or Security documents, such as Banknotes, credit and bank cards as well as identity papers and the like sold, traded, changed and to be controlled. To provide reliable evidence of the authenticity of the affected value and security documents to the relevant group of people Efforts have been made to provide Methods and devices for making these luminescent visible To achieve security elements.

The previously known and available methods and devices for However, luminescent security features are not yet visible matured to the extent that it is easy and uncomplicated to use enable reliable detection of the security features.

The present invention is therefore based on the object of a method and a device for the verification of luminescent Security features, which in and / orr on value and Security documents and objects are arranged, the Application of the device and control of the concerned Security features simple, uncomplicated, repeatable at any time, without health damage to the user and those in the immediate Surrounding people is feasible, and the control procedure with the control device without line-dependent energy and Information transfer should be executable.

The characteristic features of independent claims 1 and 8.

It is important for the present invention that for the verification of the concerned Security features that are in and / or on value and security documents and objects are arranged to ensure their authenticity when checked by means of a suitable test procedure with a corresponding test device to demonstrate that the process is easy to use, with the Visualization of security features both radiation in the ultraviolet Wavelength range as well as in the infrared wavelength range Exploitation of the down conversion effect is used. Under down conversion the following effect is understood that specially doped, luminescent material by radiation, which is in the non-visible area takes place, is excited, and according to the doping of the luminescent Materials experiences a jump on the energy band, and in the visible Spectral range after the convergence of the energy state radiation sends out. This radiation can be detected by the human eye whereby the evidence of the presence of security features is based on provide security and value documents and objects to be checked leaves.

There are two different ways to create a luminescent effect Materials application. First, it is luminescent material with imperceptible afterglow, which is called fluorescent and the second type of luminescent material, which has the effect of a Afterglow is called phosphorizing.

For the use of security features in security and However, value documents and objects do not matter which of the two luminescent materials is used. Only that is decisive Evidence of the presence of security features.

To stimulate the luminescent security features, it is necessary to use UV light to focus on the luminescent security features, what so far bulky fluorescent tubes were used. These fluorescent tubes were wired due to the high performance and also showed unwieldy dimensions, which are not easy and handy to use allow. It is important in the present invention that through the use Luminescent diodes working in the UV range have the possibility of a To build test facility, which in a very handy design with small Dimensions, e.g. in the form of a keychain. This gives the first time the possibility of a test facility cable-free and easy to transport and use.

The energy supply for the operation of the LEDs used can due to the low power consumption compared to the tubes, definitely via batteries, so-called button cells. Through this Power supply, it is guaranteed that the test equipment for Verification of luminescent security elements regardless of location can be done. Another advantage is that the test facility can be transported easily and based on the small dimensions and associated light weight available to everyone at all times can stand by this testing facility, like other everyday utensils Is always at hand.

It is important in the present invention that several diodes in one Composite are arranged so that they form a bundle which roughly approximately the same beam direction its at least partially outside the radiate visible radiation in the visible wavelength range. The stake several light emitting diodes for the purpose of emitting radiation, which are at least partially outside the visible spectral range in that by bundling the emission of rays a higher one Luminance is achieved, which makes the allows luminescent security features.

As another essential safety feature of the present Invention is at least one among this bundle of light emitting diodes Light-emitting diode arranged, which emits light in the visible range, whereby a first security feature, namely an optical operating display, Is used. Another additional safety device from The present invention is that optionally an additional acoustic operating display of those working in the invisible spectral range LEDs indicate. By introducing these safety-related Features is avoided that intentional or unintentional Eye injuries from burning the optic nerves on the retina, caused by unperceived radiation and thereby the Not triggering the flow reflex of the eye, is avoided.

Another advantage of the present invention over those previously Fluorescent lamps used is that the life of the LEDs are a multiple of the life of fluorescent lamps. Especially when the fluorescent lamps are switched on and off frequently Lifespan of this is significantly reduced, creating an average Lifespan of approximately 1000 operating hours for the fluorescent lamps is far below. The lifespan of the LEDs, however, is one Multiples of 1000 operating hours.

This results in the advantages that in the present invention Cable-independent, can be used anytime and anywhere, with a long service life equipped, test facility can be manufactured.

The realization of this completely new concept, which Use of UV light-emitting diodes (UV-LED's) provides this high flexibility for the Use case reached. The UV LEDs are in their design and in their electrical characteristics comparable to conventional light emitting diodes. LEDs for the visible wavelength range (wavelength 400 nanometers to 700 nanometers) and for the near infrared range (IR; wavelength 700 Nanometers to 1000 nanometers) have been in use for a long time. You will be in the technology above all as display elements (blue, green, yellow and red LEDs) or used in remote controls, light barriers (IR LEDs). The Desire for ever shorter wavy LEDs is justified by the fact that the optical storage density of data, for example on CD or DVD decreasing wavelength is getting bigger.

For a long time it was not possible to produce short-wave, blue light-emitting diodes because no suitable technology was available for series production. First The Nichia company has been providing corresponding light-emitting diodes for about 5 years, that this technological gap with the production of series products Generation of blue light or laser diodes closes. By a Further development of this technology has now succeeded in first samples of To produce LEDs of even shorter wavelengths.

These LEDs work in a wavelength range of 370 nanometers and thus have a wavelength similar to that of commercially available UV lamps (Wavelength 375 nanometers).

geringe Abmessungen (Standard-LED-Gehäuse ca. Höhe: 6,2 mm, Durchmesser 5 mm), geringe Leistungeaufnahme von ungefähr 60 Milliwatt, hohe optische Leistung von ungefähr 750 Milliwatt und eine lange Lebensdauer von ungefähr 2000 Betriebsstunden. Daraus ergibt sich, daß die Leuchtdiode ungefähr eine doppelt so lange Lebensdauer aufweist, wie eine Leuchtstoffröhre, deren Lebensdauer aufgrund hoher Ein- und Ausschalthäufigkeit noch zusätzlich deutlich reduziert wird.

The advantages of such UV LEDs compared to a UV fluorescent lamp are:

small dimensions (standard LED housing approx. height: 6.2 mm, diameter 5 mm), low power consumption of approximately 60 milliwatts, high optical power of approximately 750 milliwatts and a long service life of approximately 2000 operating hours. The result of this is that the light-emitting diode has a service life that is approximately twice as long as that of a fluorescent tube, the service life of which is additionally significantly reduced due to the high frequency of switching on and off.

Another advantage of the light emitting diodes over the fluorescent tubes is in that the light emitting diodes immediately provide their full optical power as soon as they are energized. The fluorescent tube however, it takes a certain amount of time to ignite the gas and thus to achieve their luminosity and operational readiness. In order to the disadvantage of the waiting time between are automatically connected Switch-on time and the first operational state of the fluorescent tube as well as the disadvantage of the significantly higher power consumption.

A power supply is required for the correct operation of these LEDs between 3.5 volts and 4.5 volts necessary. This power supply can using appropriately sized batteries for a satisfactorily long time Service life can be achieved.

A consistently intense luminosity can be achieved by using a Constant current source for the supply of the UV LEDs can be achieved. Care the transistors used to ensure that the UV LEDs are always the same Voltage drops, which results in constant luminosity when in use. By using such a constant current source, it is also possible Use battery voltages above 4.5 volts, which are caused by the electronics the correspondingly required values are limited. With the previously specified Data thus generates a power consumption of approximately 10 milliamperes. Under These operating conditions have a lifespan of approximately 2000 Operating hours according to the manufacturer's specification. When using conventional alkaline batteries of the type LR44 (1.5 volts) result in a Operating time of approximately 12 hours. Set one for reviewing one Security and value document for a period of 10 seconds a number of test operations, which is 4320 operations.

The different rapid decay behavior of the individual luminescent Use colors that are used as security features to advantage can, the present invention provides that the suggestion for delivery luminescent radiation caused by the infrared or ultraviolet Radiation, by pulse method for the operating voltage supplied used LED's is influenced so that different colors the correspondingly excited luminescence security features on the value and Sign off security documents and objects. Background this changing color spectrum of the luminescent features emitted radiation is the superposition of emitted luminescent Radiation from different frequency ranges due to use of different colors, the individual decay constants of different Order of magnitude. It is advantageous to use luminescent colors which have significantly different decay constants. This gives the advantage is that with pulsed or intermittent and / or modulated Form of power supply for the relevant LED's different Emission characteristics of the security features are generated. This Characteristics are expressed in the fact that, for example, in the case of unpulsed or unmodulated form of voltage supply both of the at least two different luminescent colors used their maximum Have reflection. This results in a mixture of colors, which in Ratio of the amount of security features applied and their Retroreflectivity depending on its retroreflective power and its Decay constant occurs. With the pulse method now starting or intermittent and / or modulating change in the voltage supply the LEDs are also directly dependent on this type of voltage Supply voltage the radiation of infrared and ultraviolet radiation on the security features. The ultraviolet or infrared radiation, which is released from the semiconductor solid-state elements, is therefore directly from dependent on the voltage, since this immediately gives its full radiation power when applied of a corresponding voltage and this until the switch-off time maintained. Thus, the luminescent security features in the Form of the supplied operating voltage from the infrared and ultraviolet Radiation irradiated. Due to the intermittent and / or modulated form of this Power supply are now the retroreflective characteristics of the for Security features used luminescent colors depending on their Decay constants recorded by the eye. For example, if the color A only Has 1/10 of the decay constant of color B, so is corresponding intermittent and / or modulated form of the supply voltage for the LEDs make it possible to influence the radiation characteristics of color A that - compared to the radiation intensity of color B - it goes to zero. This results in a retroreflective effect which only recognizes the color B. leaves. If the pulse ratio of the operating voltage changes so that that the pulse ratio significantly longer switch-on than switch-off periods color A sends again, which is a much lower one Radiation constant shows as the color B, again perceptible to the eye Radiation. This results in a frequency mix of the retroreflection according to the relationships between the colors A and B, which results in a Perceive color change of the emitted luminescent colors for the eye leaves.

As an example, the color A is green and the color B is blue pulsed power supply the reflection of the security elements the Color blue / green. With a pulsating and / or modulating form The voltage supply will change over time in the cycle the color A - i.e. green - always between the voltage switched on and off weaker and the color blue would remain constant. This modulation can go so far be driven until the reflection of the color green has completely subsided is. In this case the color would now be blue, based on its large size Decay constant, still emit visible radiation.

The present invention now provides that the modulation method for Operating voltage of the LED's are optional when checking the value and Security documents and objects vary. This allows the whole Frequency spectrum of the applied security features can be checked. This is shown by a change in the retroreflective colors, which change results from the sum of the retroreflective frequencies.

Another alternative power supply results from the use of a DC / DC inverter. This IC is able to measure the voltage of a battery multiply. In this way it is possible to add electronics for the UV LEDs develop that only needs one or two LR44 batteries. This embodiment is an alternative to the embodiment with the Constant current source.

Regarding the housing design for the installation of the UV LEDs and the corresponding embodiments, several embodiments were developed. An embodiment of this housing is designed so that it due to its small dimensions on the keychain in your pocket can be worn without hindering the owner. The ergonomics of the UV LEDs prevent accidental actuation when carried in bags is prevented. Care was also taken to ensure that the button for the Operation of the control device for both right and left-handers is equally convenient to use. A clearly audible and palpable Switch-click also ensures that the user does not accidentally Commissioning of the control device completed.

The core housing is made of acrylonitrile butodiene styrene copylymere (ABS) in the thermoplastic injection molding process. Are preferred elastomeric elements are used so that the function of the test facility through Floor traps from hip or shoulder height, even on hard floors, such as Stone floors or the like, is not affected.

The high breaking strength of the test facility achieved in this way is another Security feature of the present invention. Another feature of Safe operation of the test equipment lies in the fact that the housing design is designed such that it is closed to protect against splashing water. In the further the UV LEDs are arranged in the housing in such a way that they are scratched by protruding elements is avoided and so the opening angle of approximately 10 ° of the emitting UV and / or IR light is retained at all times.

Another embodiment of the present invention provides that this as stationary device is built. This stationary UV LED lamp comes with several LEDs are equipped to provide a uniform, intensive illumination guarantee. This verifier can optionally be equipped with a UV filter his. This filter can remove the annoying, visible, blue light components of the UV LEDs reduce and thus an improved visibility of the luminescence enable. In addition, the color fastness of the luminescence compared to that restored with UV lamp.

In order to enable a corresponding value and security product or object to be recognized when it is brought into the control position, it is provided to install a proximity sensor. This proximity sensor switches on the power supply for the LEDs when a value and security product or object is detected. This enables the control process described above to be triggered.
The UV-LED verifier is therefore equipped with a sensor that detects whether a security document to be checked is under the device. The UV LEDs are only switched on in this case. Such a sensor could be implemented using a simple light barrier. The advantage of this solution is that the UV LEDs are only switched on when they are needed. The service life is significantly increased in this operation and exceeds that of a stationary UV lamp, with which such operation is not possible, many times over. In addition, you get a reduced energy consumption and less UV rays than with continuous operation, as is usual for the UV lamps.

Another interesting possibility arises from the combination of UV LEDs and infrared LEDs. In addition to those under UV light luminescent Security features are also increasingly used feature materials that under irradiation with infrared light in the visible lighting area (down-conversion or anti-stocks) converge. A combination of UV and IR LEDs is therefore sensible, since it checks both security features in this way can be.

By developing this stationary device, both stationary and portable test equipment possible.

Are UV and IR luminescent security features in one graphic Element integrated, so are both by using both wavelength ranges Security features verifiable. The two differ different security features through different colors. Thus it results a simple and eye-catching verification of the existing Security features.

Based on the following description of the figures, the present invention, based on several embodiments of the present invention, described.

Figur 1:

eine Schnittdarstellung einer Ausführungsform der IR- und UV-LED-Prüfeinrichtung,

Figur 2:

eine Draufsicht nach Figur 1,

Figur 3:

eine Schnittdarstellung einer weiteren Ausführungsform nach Figur 1,

Figur 4:

eine senkrechte Schnittdarstellung nach Figur 4,

Figur 5:

eine Schnittdarstellung im Schnitt A-A nach Figur 3,

Figur 6:

eine Schnittdarstellung im Schnitt B-B nach Figur 3,

Figur 7:

den inneren Aufbau der Prüfeinrichtung nach Figur 3,

Figur 8:

den inneren Aufbau der Prüfeinrichtung nach Figur 4, und

Figur 9:

den inneren Aufbau der Prüfeinrichtung nach Figur 6.

Show it:

Figure 1:

2 shows a sectional illustration of an embodiment of the IR and UV LED test device,

Figure 2:

2 shows a top view according to FIG. 1,

Figure 3:

2 shows a sectional illustration of a further embodiment according to FIG. 1,

Figure 4:

3 shows a vertical sectional view according to FIG. 4,

Figure 5:

3 shows a sectional illustration in section AA according to FIG. 3,

Figure 6:

4 shows a sectional illustration in section BB according to FIG. 3,

Figure 7:

the internal structure of the test device according to Figure 3,

Figure 8:

the internal structure of the test device according to Figure 4, and

Figure 9:

the internal structure of the test device according to Figure 6.

FIG. 1 shows a UV-IR-LED pointer, which has 5 UV-LEDs in a housing 2, IR LEDs 3, LEDs in the visible wave range 4, and batteries 6 includes. There is also an acoustic display 12 and a button 9 in this Representation of this embodiment of the present invention recognizable. At Pressing the button 9 on the electronics 6 energy on the LEDs 2,3,4 voltage in the intended operating voltage level delivered and this stimulated to glow. Furthermore, the acoustic display 12 for emitting a signal by actuating with the appropriate spring force provided button 9 causes. Through this acoustic signal, as well the LED in the visible wave range ensures that none invisible radiation can escape from the LED's without warning signals be delivered in both optical and acoustic form. The levy The optical signal is used to trigger the closing reflex of the eye muscles. The emission of the ultraviolet or infrared radiation from the UV / IR LEDs serves to stimulate the luminescent security features of the checking value and security documents and objects. Due to the Excitation by ultraviolet or infrared light is given to the Security features a down-conversion energy transfer takes place which the safety features for radiation in the visible wavelength range stimulates.

Figure 2 shows a plan view of the embodiment of Figure 1, the Top view is from the direction in which the emitted radiation from the LED's is directed. With this arrangement, several LEDs can be seen, which in one bundled state on the front side of the housing 5 of the UV-IR LED pointer are arranged.

Figure 3 shows a sectional view of a further embodiment of the Present invention, the LED combination UV-LED 2, IR-LED 3 and LEDs in the visible wave range 4 are shown as a single unit. Furthermore, the electronics 8 are the buttons 9 and the batteries 6 with the contacts 7 recognizable in the housing 5. The operation of this embodiment corresponds in principle the mode of operation of the previously described embodiment.

FIG. 4 shows a vertical sectional view according to FIG. 3. In this The ergonomic design of the handy UV / IR LED pointer is clear in form recognizable. The arrangement of the components housing 5, battery 6 with contact 7 and button 9 with cover 11 and the heart, the LEDs 2,3,4, clearly presented. At the bottom of the case is an ergonomic one Grip recess 10 recognizable. There is also an opening 13 for receiving one Ring or a similar attachment in the housing 5 can be seen. The button 9, which is arranged within the housing, with the cover 11, the splash-proof, actuated. This illustration is good too recognizable that an actuation of the button can only take place if deliberately on the cover 11 which is lower than the rest of the housing the button 9 pressure is exerted. This pressure needs a certain one Exertion of force, which ensures that an unintentional actuation of the UV / IR LED pointers is avoided.

FIG. 5 shows a sectional view through section A-A of FIG. 3. In this illustration, the arrangement of four batteries 6 in the housing 5 shown. These batteries are used to supply power to the UV LEDs IR-LED's, as well as the LED in the visible wave range and the acoustic Operating display 12.

Figure 6 shows a sectional view according to section B-B of Figure 3. Here is in Housing 5 on the left side of the recessed grip 10 can be seen, which also in the Figure 4 is shown in the lower left area. Furthermore, in the middle is the Button 9 and the LED unit 2,3,4 shown for the LEDs. In addition are still parts of the electronics 8 recognizable

In Figure 7, the internal structure of this embodiment is the present Invention recognizable. Similar to Figure 3 is on the left side Group representation for the LEDs 2,3,4 with their connections shown. Furthermore is centrally in the middle of the button 9 with the electronic surrounding all around Components 8 recognizable. In the right part of this illustration are four batteries 6 shown in the form of button cells, which by contacts 7 with the Electronics 8 are connected.

In Figure 8, this representation is rotated by 90 °, which on the left side Commonly shown unit for the LEDs 2,3,4 with their connections Connection with the necessary electronics is shown. In the middle is a electronic component 8 recognizable, behind which by a higher Structure recognizable button 9 is positioned. To the right of this are contacts 7 and the batteries 6 shown.

FIG. 9 shows a front view of this inner part of this embodiment of the present invention. In the center in the middle is the single unit combination of LEDs 2,3,4 shown. The button 9 is located behind it and an electronic component 8. In the upper and lower area, the contacts 7 recognizable with their connections to the board.

The embodiments of the present invention thus described are not to be understood as restrictive, on the contrary, they are only a part the various possible embodiments of the present invention.

Drawing legend

1

UV / IR LED pointer

2nd

UV LED

3rd

IR LED

4th

LED visible wave range

5

casing

6

battery

7

contacts

8th

electronics

9

Button

10th

Recessed grip

11

cover

12th

acoustic display

Claims (12)

Method for controlling luminescent security features which are arranged in and / or on valuable and security products and objects, characterized in that the use of radiation from solid electroluminescent semiconductor elements in the invisible wavelength range means that the luminescent security features for emitting radiation in the visible wavelength range be stimulated. A method according to claim 1, characterized in that the radiation from the electroluminescent solid-state semiconductor elements takes place in a pulsed or intermittent and / or modulated form and such a higher radiation power and / or less energy consumption is given and / or by using at least two luminescent security features with different decay behavior Coupled with different luminescent color by varying the frequency of the radiation from the electroluminescent semiconductor solid-state elements to emit radiation of different wavelengths in the visible wavelength range and thus lead to a different color impression. Method according to one of the two preceding claims, characterized in that the emission of ultraviolet (UV) radiation is generated from an electroluminescent semiconductor solid-state element which is arranged in an easy-to-use, matchbox-sized control device. Method according to one of Claims 1 and 2, characterized in that the emission of infrared (IR) radiation is generated from an electroluminescent semiconductor solid-state element which is arranged in an easy-to-use control device approximately the size of a matchbox. Method according to one of the preceding claims, characterized in that a combination of ultraviolet radiation and infrared radiation for excitation of the luminescent security features is carried out from UV and IR electroluminescent semiconductor solid elements arranged together in the control device and / or a combined UV / IR electroluminescent semiconductor solid element. Method according to one of the preceding claims, characterized in that for safety reasons and to protect the retina of the eyes, visible continuous and / or flashing radiation is emitted using a lamp element, preferably an LED, in the visible wavelength range at the same time as that Radiation is emitted from the electroluminescent semiconductor solid-state elements in the invisible wavelength range. Method according to Claim 6, characterized in that, in addition to the optical operating display, an acoustic operating display, which emits radiation in the invisible wavelength range, emits an acoustic signal during the operation of the lighting element. Device for controlling luminescent security features which are arranged in and / or on valuable and security products and objects, characterized in that at least one UV-electroluminescent semiconductor solid element (2) and / or at least one IR-electroluminescent semiconductor solid element (3) and optionally a luminous element, the radiation of which lies in the visible wavelength range, is arranged in a bundle shape in a housing (5) and emits a bundled radiation which is both in the visible and in the non-visible wavelength range. Apparatus according to claim 8, characterized in that a button (9) by means of a cover (11) which is arranged recessed relative to the rest of the housing (5), the electrical contact for the operation of electroluminescent semiconductor composite combination (2,3,4) by overcoming the spring force of the button. Device according to one of claims 8 or 9, characterized in that the energy supply for the bundle of electroluminescent solid semiconductor elements (2, 3, 4) is based on batteries or rechargeable batteries and a constant current source which ensures a constant current supply to the fluorescent solid semiconductor elements and / or alternative energy source, such as a solar module, a piezo transducer and the like. Device according to one of claims 8 or 9, characterized in that the energy supply for the bundle of solid electroluminescent semiconductor elements (2, 3, 4) takes place on the basis of energy sources and a DC / DC converter which converts the voltage from the energy source used to the required one Operating voltage for the electroluminescent solid semiconductor elements converts. Device according to one of Claims 8 to 11, characterized in that the UV and / or IR electroluminescent semiconductor solid-state elements (2, 3) are switched on by a proximity sensor such that the switch-on is carried out automatically by detection of a corresponding value and safety product or -Object is brought into the control position.

Images