Abstract:
An illuminated card device formed from sheet stock, for use as a greeting card or the like. One or more EL lamps are attached either flat against the card or mounted as pop-up elements. Two wires lead out from the EL lamps to a high voltage driver circuitry that converts a low voltage signal into an AC high voltage signal (approximately 40V to 300V peak to peak.) This circuitry is mounted on a PCB, hidden from view. A sliding tab in the shape of a ‘t’ slides through two slits in the card. Metal elements are mounted to the tab and between the two slits. When the card is opened, the two metal elements make contact, creating an electrical short to allow the battery to supply current to the high voltage conversion circuit. The high voltage driver circuit provides signals to illuminate the EL lamps.

Description:
FIELD OF THE INVENTION  
         [0001]    This invention relates to the field of greeting cards and displays made of folded sheet stock. More particularly, the invention relates to illuminated greeting cards and displays for advertising or similar purposes and for novelty items.  
         BACKGROUND OF THE INVENTION  
         [0002]    This invention relates to illuminated greeting cards. BACKGROUND—DESCRIPTION OF PRIOR ART  
           [0003]    Consumers have always been looking for an escape from the traditional two-dimensional greeting card with printed artwork and greeting inside, especially when the card is given to a close friend, wife or husband. Musical cards and pop-up cards helped to satisfy some of the demand. In the meantime, lighting methods developed using LEDS, lamps and miniature light bulbs were used to farther enhance the cards. Although illuminated greeting cards and lit displays have been proposed, they have not experienced commercial success and suffered from a number of disadvantages.  
           [0004]    (a) First, the illumination devices (LEDS, lamps, and miniature light bulbs) are often too large, hard, thick or bulky to be incorporated into a thin flexible greeting card. To provide sufficient lighting, many LEDS or lamps had to be used, causing the card to gain considerable size and weight, making the card not unsuitable for mailing.  
           [0005]    (b) Also, the cost of the electrical components is prohibitive towards manufacturability. The high number of LEDS or lamps is a large part of the total costs.  
           [0006]    (c) The results of lighting schemes such as LEDS are not visually pleasing; LEDS provide point sources of light rather than a uniform light source (i.e.: the lighted EL display on a cellular phone.)  
           [0007]    (d) Lighting schemes such as LEDS and lamps cannot be seamlessly incorporated into pop-up cards because of their size and bulk. Pop-up cards need many thin elements that can collapse together when the card is closed. However, LEDS and lamps occupy a lot of thickness, making it difficult to incorporate. As an example, U.S. Pat. No. 4,363,081 issued Dec. 7, 1982 to Robert Wilbur showed a LED-driven greeting card. However, the LEDs were attached onto a stiff printed circuit board, and the LEDs themselves were cylindrical and bulgy in shape.  
           [0008]    (e) LEDS and lamps are hard, stiff devices that do not blend in well with a greeting card which is generally comprised of flexible materials.  
           [0009]    (f) Such illumination schemes such as LEDS and miniature light bulbs can easily be destroyed if dropped or accidentally stepped on.  
           [0010]    Objects and Advantages  
           [0011]    Accordingly, besides the objects and advantages of the thin EL-based greeting card described in my above patent, several objects and advantages of the present invention are:  
           [0012]    (a) to provide a thin, light-weight illuminated greeting card;  
           [0013]    (b) to provide an inexpensive, low-component count illuminated greeting card;  
           [0014]    (c) to provide an illuminated greeting card with uniform lighting on the illuminated surface;  
           [0015]    (d) to provide an illuminated greeting card that can incorporate pop-up features or 3D features with illumination;  
           [0016]    (e) to provide a flexible illuminated greeting card;  
           [0017]    (f) to provide a rugged illuminated greeting card;  
           [0018]    Accordingly, it is the object of the present invention to provide an illuminated greeting card, novelty item, gift package, advertising display, or the like, which is flexible, ultra-thin, durable, uniformly lit, and suitable for 3-D cards or pop-up cards.  
           [0019]    It is a further object of the invention to provide an illuminated device that can be automatically switched on or off depending on whether the card is opened or closed.  
           [0020]    Another important object of the invention is to provide an illumination element that can be attached to the front, the back, or the inside of the card, or that can be used as a pop-out element of a greeting card.  
           [0021]    Other objects and features of the present invention will become apparent from the following description, which should be read in connection with the accompanying drawings. It is to be understood, however, that this description and the drawings are intended for the purpose of illustration only and not as a definition of the limits or scope of the invention. The scope of the invention is intended to be limited only as set forth in the claims appended at the end of the description.  
         SUMMARY  
         [0022]    In accordance with the present invention an illuminated greeting card comprises a folded card formed from sheet stock or plastic, a power supply such as a button cell battery, an EL display or EL lamp, a high voltage driver circuit to illuminate to the EL lamp, and a switch for turning on or off the EL lamp. 
       
    
    
     DRAWINGS  
       [0023]    Drawing Figures  
         [0024]    In the drawings, closely related figures use the same number but different suffixes.  
         [0025]    [0025]FIGS. 1A and 1B show an illuminated greeting card with two EL lamps connected in parallel, switched on or off by a sliding contact switch.  
         [0026]    [0026]FIG. 2 shows an elevational front view of a typical EL driver circuit based off Supertex&#39;s™ HV825 chip.  
         [0027]    [0027]FIG. 3 shows an elevational front view of a typical EL driver circuit based off Durel&#39;s™ D340B chip.  
         [0028]    [0028]FIG. 4 shows an elevational back view of a typical EL driver circuit based off Supertex&#39;s HV825™ chip.  
         [0029]    [0029]FIG. 5 shows an elevational back view of a typical EL driver circuit based off Durel&#39;s D340™ chip.  
         [0030]    [0030]FIG. 6 shows a front perspective view of an EL illuminated greeting card in a semi-closed position with the contact switch mounted on the back of the card.  
         [0031]    [0031]FIG. 7 shows a front view of an EL illuminated greeting card in an open position with the contact switch mounted on the back of the card.  
         [0032]    [0032]FIG. 8 shows a perspective view of a pop-up EL illuminated greeting card with the EL lamp acting as a pop-up element. 
     
    
       [0033]    Reference Numerals in Drawings  
                                       10 square EL lamp   70 first fold of card       11 heart-shaped EL lamp   71 second fold of card       12 greeting card   72 middle fold of card       14 sliding switch   73 inside front cover       20 EL driver chip   74 inside back cover       21 inductor   75 outside front cover       22 first resistor   76 outside back cover       23 second resistor   77 front cover       24 high voltage diode   78 back cover       25 high voltage capacitor   80 first slit in card for EL lamp       30 trace for v+ terminal of battery   81 second slit in card for EL           lamp       31 trace for v− terminal of battery   82 paper pop-up element       32 EL driver output 1   83 EL lamp pop-up element       33 EL driver output 2   84 folded rectangular paper       40 printed circuit board (PCB)   85 vertical fold in square paper       41 flex circuit board   86 triangular fold in square           paper       42 PCB type circuit   87 extended attachment to           triangular fold       50 attachment   88 attachment to 3-D element       51 hinge   89 middle fold of triangular fold       52 tab   90 via for positive (v+) battery           connection       53 first slit in paper   91 via for negative (v−) battery           connection       54 second slit in paper   92 negative (v−) connection to           battery       55 first metal element   93 positive (v+) connection to           battery       56 second metal element   100 battery       57 metal element aligned with edge   101 EL driver chip       58 metal element protruding from edge   103 first slanted fold of           triangular fold       59 T-shaped head of tab   104 second slanted fold of           triangular fold           105 hinge                  
 
       DETAILED DESCRIPTION  
       [0034]    Description—FIGS.  1 A and  1 B—Preferred Embodiment  
         [0035]    A preferred embodiment of the invention in the form of a greeting card  12  is shown in FIG. 1. Here, the card is shown in its open position from an inside perspective view. The front cover comprises a front cover section  75  and an inner front cover section  73  hinged about a fold  70 . The back cover comprises a back cover section  76  and an inside back cover section  74  hinged about a fold  71 . The inside front cover section  73  and inside back cover section  74  are hinged about a middle fold  72  which is directed in the opposite direction as the other two folds  70  and  71 .  
         [0036]    An EL lamp  10  is attached to the inside front cover section  73  by an adhesive such as double-sided sticky tape. On the inside back cover  74 , another EL lamp  11  is attached to the card. A printed circuit board (PCB) or some form of printed conductive tracing  42  is attached to the back of the inside front cover so that it is hidden from view. A flexible PCB is preferred as it would allow the card to be as thin as possible. This PCB contains the high voltage driver circuitry needed to drive the EL lamps. From this PCB, two wires  32  and  33  stream out and route to the two EL lamps. The wires may be attached to the card by tape, glue or some other form of adhesive substance. Two slits in the card  80  and  81  allow the wires to surface and attach to the two terminals of the EL lamps. If so desired, the EL lamp could be directly glued and connected to the PCB without occupying much space and eliminating the wires.  
         [0037]    Two additional wires  30  and  31  route from the PCB and connect to two metal elements  55  and  56  to form a sliding switch  14 . FIG. 1A shows an enlarged view of the sliding switch  14 . The inner front cover of the card has two slits  53  and  54  that allow a T-shaped tab  52  to pass through. The T-shaped head  59  of this tab will not fit through the two slits and will determine how wide the card can open. The long skinny end of the tab is bent about a hinge  51  and attached by the end  50  to the inner back cover section of the card. One metal element  56  is attached to the middle of the two slits facing down. The other metal element  55  is attached facing up to the sliding. Thus, as the card is opened and the tab slides through the slits, the two metal elements would make contact and complete an electrical circuit.  
         [0038]    Several interesting variations of the invention also come to mind. First, paper cutout words could be superimposed on top of the El lamps to create a backlit effect on the words. Also, the EL lamps themselves could be used as a sketchpad so that a person could sign his or her name directly on the lighted lamp to create interesting effects.  
         [0039]    FIGS.  2 - 5 —Circuits to Drive EL Lamps  
         [0040]    [0040]FIGS. 2 and 3 show two circuits that can drive one or more EL lamps. In order to be illuminated, an EL lamp requires a high voltage AC signal, approximately 40V to 300V peak to peak that can be generated by a number of different generic circuits. FIGS. 2 and 3 show two such possible circuits based off EL inverter or EL drivers.  
         [0041]    [0041]FIG. 2 shows a front elevational view of a typical circuit based off Supertex&#39;s™ HV825 EL driver chip  101 A suitable for driving one or more EL lamps. All the circuit elements are mounted on a flexible PCB (flex-circuit)  41 . The EL driver  101 A is attached to two 1 MΩ resistors  22  and  23  that are connected to a v+ trace  30 . A 560 μH inductor  21 A is placed between the v+ trace and the fourth pin of the EL driver. A 1N4148 high voltage diode  24  and a 10 nF high voltage capacitor  25  connect in series to the v− trace  31  to complete the circuit. On the PCB, a metal via  90  allows the trace  31  to route to the back of the PCB where it connects to a battery. Another metal via  91  routes the v− trace to the back of the PCB board to connect with the negative end of the battery.  
         [0042]    [0042]FIG. 3 shows a front elevational view of a typical circuit based off Durel&#39;s™ D240B EL driver chip  101 B. Here, the chip requires one 3.3 mH inductor  21 B connected between the sixth and eighth pins of the EL driver chip. Once again, metal vias  90  and  91  allow the traces for the switch to extend to the back of the PCB  42  to connect to the battery.  
         [0043]    [0043]FIG. 4 shows the back elevational view of the HV825-based circuit of FIG. 2, and FIG. 5 shows the back elevational view of the D340B-based circuit of FIG. 3. A battery  100  is held clamped against the PCB by a metal clip  93 . One such suitable battery is the SONY CR1220-1 lithium coin battery. The clip  93  connects to the front side of the PCB through via  90 . Underneath the battery lies a metal plate or electrically conductive surface  92  which connects through via  91  to the other side of the PCB. The battery need not be directly attached to the back of the PCB. It can be attached anywhere on the PCB or greeting card as long as an electrical conductive path is established. For instance, the battery can be simply taped to the back of the inner front cover section, and the wires  30  and  31  can be routed to the location of the battery. In order to provide more voltage or current, two or more batteries could be placed in series or in parallel. Also, the electrically conductive surface  92  could be replaced by a metal spring to hold the battery more securely.  
         [0044]    [0044]FIGS. 2 through 5 show specific application circuits used to drive the EL lamps. However, many generic EL inverters and EL driver circuits exist depending on the driver chip used and the external components selected. Although these circuits have only been described with regard to preferred embodiments, it should be understood that variations and modifications as would be obvious to one having ordinary skill in this art may be made without deviating from the scope if this invention. For instance, circuits can be configured to flash the EL lamps or sequentially turn on and off individual EL lamps.  
         [0045]    [0045]FIG. 6 and FIG. 7—Alternative Embodiments of the Illuminated Greeting Card  
         [0046]    [0046]FIG. 6 shows an alternative embodiment of a greeting card according to the present invention. Here, instead of using a sliding switch member to close the EL driver circuitry, two contact metal elements are mounted on the spine of the card. One metal contact  57  aligns with the folded edge  72  of the card. The other metal contact  58  protrudes past the folded edge of the card. Thus, when the card is closed or partially closed, the two metal contacts do not short together and complete the circuit.  
         [0047]    In FIG. 7, the card is in a fully opened position such that the two metal contacts  57  and  58  will overlap and complete the circuit. Once again, the PCB  42  is shown along with the two connections  32  and  33  to the EL lamp  10 . The two wires  30  and  31  that are used to complete the circuit are brought out from the PCB and connected to the two metal contacts  57  and  58 .  
         [0048]    [0048]FIGS. 8A, 8B, and  8 C—A Pop-Up Illuminated Greeting Card With the EL Lamp as A Pop-Up Element  
         [0049]    [0049]FIG. 8A shows an inside perspective view of an illuminated greeting card with the EL lamp acting as a pop-up element. Once again, the EL lamp is attached to two driver outputs  33  and  32  that route out through a slit  80  in the card from a PCB circuit  42 . The PCB is attached behind the inner front cover  73 . Two wires and  31  route to a sliding switch  14 . Here, an EL lamp cut in the shape of a ghost  83  leans forward through the opening of a television-shaped paper element  82  when the card is opened. Both the EL lamp and the television are made to pop up by use of a folded rectangular paper  84 .  
         [0050]    [0050]FIG. 8B shows in detail the folded rectangular paper that is used to prop open the ghost-shaped EL lamp while FIG. 8C shows the rectangular paper used to prop open the television cutout. This rectangular paper consists of a bottom vertical fold  85  in the same direction as the middle fold of the greeting card  72 . The top half of this square paper has a triangular fold  86  with the middle fold  89  directed against the direction of the greeting card and two slanted folds  103  and  104  in the same direction as the greeting card. To one side of this triangular fold is attached a paper protrusion  87  with the end acting as an attachment area  88  bent about hinge  105  so that it is parallel with the face of the card. The pop-up EL lamp and the television-shaped element are glued to this attachment area  88 . Thus, when the card closes, the triangular fold  86  and the attached pop-up elements collapse together.  
         [0051]    Advantages  
         [0052]    From the description above, a number of advantages of the EL-based illuminated greeting card become evident:  
         [0053]    a) The paper-thin EL lamp can be placed anywhere on the card without adding too much thickness.  
         [0054]    (b) In order to light a large area, only one EL lamp needs to be used rather than several point light sources.  
         [0055]    (c) Surfaces can be uniformly illuminated.  
         [0056]    (d) As in the case of the pop-up embodiment, the EL lamp can be easily shaped and incorporated into one of the pop-up elements.  
         [0057]    (e) The greeting card can be made to be very flexible using a flexible EL lamp and a flexible PCB circuit to drive the lamp.  
         [0058]    (f) With the major elements of this illuminated card being flexible, damage is less likely to occur when the card is bent, dropped or accidentally stepped upon.  
         [0059]    (g) Senders of the greeting card can directly sign their names on the EL lamps to create interesting effects.  
         [0060]    (h) The EL lamps can be used to backlight words and pictures.  
         [0061]    Conclusion, Ramifications, and Scope  
         [0062]    Accordingly, the reader will see that the EL-based greeting card can produce unique and novel illumination effects that have not been seen to date. Furthermore, because of the ultra-thin nature of EL, pop-up cards can now be readily made with illumination. Having thus described a preferred embodiment and alternative embodiments of the present invention, it is apparent that various alternatives, modifications and alterations thereto will readily occur to those familiar with the art, without departing from the spirit and scope of the invention. Accordingly, it is intended that all such obvious modifications, alterations, and improvements are part of this invention and that the invention is limited only as defined in the following claims.