Patent Publication Number: US-7583566-B2

Title: Electronic device with an electroluminescence lens mask

Description:
BACKGROUND OF THE INVENTION 
   This invention relates generally to electronic devices that incorporate electroluminescent (EL) technology, such as wristworn devices, and in particular, to a wearable electronic device that incorporates an EL layer above the dial so as to facilitate the illumination of indicia, whether embedded and/or surface indicia (as disclosed below), under low lighting conditions. 
   Electroluminescent (EL) technology is well known in wristwatches, a pioneer in the field being companies such as Timex Corporation. The construction of such EL lamps is now well known, and is further described in several, if not many existing patents, examples of which can be found in U.S. Pat. Nos. 4,527,096 and 6,515,416. 
   However, these (and presumably other) patents are believed to focus only on the use of EL technology for backlighting of the dial or display, such as an LCD. That is, the present inventor is not aware of any use of EL technology (i.e. as a lamp) wherein the lamp/layer is positioned in front of the dial or display so as to facilitate illumination of (e.g.) embedded and/or surface indicia, not on the dial or LCD display, during low lighting conditions. 
   Such a device, however, is believed to be desirable in that it further facilitates the use and reading of the device&#39;s functions during low lighting conditions, thereby providing at the least, increased functionality, ease of use and enjoyment of the device. The present invention provides the aforementioned advantages and objectives, as well as those set forth below. 
   SUMMARY AND OBJECTIVES OF THE INVENTION 
   It is thus an objective of the present invention to overcome the perceived deficiencies in the prior art. 
   It is another objective and advantage of the present invention to provide an electronic device that facilitates its use in low lighting conditions. For example, it is an objective and advantage of the present invention to provide an EL lamp in front of the display or dial in such a way as to facilitate the reading/viewability of, for example, embedded and/or surface indicia in and/or on a translucent ink/film layer. 
   Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification. 
   The invention accordingly comprises the features of construction, combination of elements and arrangement of parts and sequence of steps which will be exemplified in the construction, illustration and description hereinafter set forth, and the scope of the invention will be indicated in the claims. 
   To carry out the advantages and objectives set forth above and below, the present invention, generally speaking, in a first embodiment, is directed to an illumination assembly for an electronic device, wherein the electronic device comprises a casing within which is positioned at least a display assembly for displaying information, wherein the illumination assembly comprises an electroluminescent assembly, coupled in the casing, having a first surface and a second surface, wherein the first surface is in facing alignment with the display assembly; a translucent ink/film layer having a first surface and a second surface, wherein the first surface is positioned in facing alignment with the second surface of the electroluminescent assembly, and wherein the second surface of the translucent ink/film layer has surface indicia thereon; a lens in facing alignment with the second surface of the translucent ink/film layer; wherein the illumination assembly is sealed in the casing; and whereby upon illumination of the electroluminescent assembly, the visibility of the surface indicia is facilitated. 
   In an alternative embodiment, the present invention is directed to an illumination assembly for an electronic device, wherein the electronic device comprises a casing within which is positioned at least a display assembly for displaying information, wherein the illumination assembly comprises an electroluminescent assembly, coupled in the casing, having a first surface and a second surface, wherein the first surface is in facing alignment with the display assembly; a translucent ink/film layer having a first surface and a second surface, wherein the first surface is positioned in facing alignment with the second surface of the electroluminescent assembly, and wherein the translucent ink/film layer has indicia therein; a lens in facing alignment with the second surface of the translucent ink/film layer; wherein the illumination assembly is sealed in the casing; and whereby upon illumination of the electroluminescent assembly, the visibility of the indicia is facilitated. 
   In a specific embodiment, the wearable electronic device is a wristwatch. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above set forth and other features of the invention are made more apparent in the ensuing Description of the Preferred Embodiments when read in conjunction with the attached Drawings, wherein: 
       FIG. 1  is an exploded view of an electronic device constructed in accordance with the present invention, illustrating an illumination assembly constructed in accordance with the present invention; 
       FIG. 2  is a simplified cross-sectional view of  FIG. 1 ; 
       FIG. 3  illustrates the electronic device of  FIG. 1  under normal lighting conditions; 
       FIG. 4  illustrates the electronic device of  FIG. 1 , and in particular, exemplary indicia being illuminated under low lighting conditions; and 
       FIG. 5  illustrates an exemplary ink/film layer  50 . 
   

   Like reference numerals used in the various figures represent like parts or elements, but not every part or element in each figure may be indicated with a reference numeral. 
   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Reference is first made to  FIGS. 1 and 2 , which are respectively exploded and cross-sectional views of a wearable electronic device, generally indicated at  10 , constructed in accordance with the present invention. 
   Generally speaking, in accordance with a first embodiment, wearable electronic device  10  (“device  10 ”) comprises a module or casing, generally indicated at  15 , within which is positioned, among other features and elements, a display assembly for displaying information. As will be understood, the display assembly may comprise a dial and display hands, such as that disclosed in U.S. Pat. No. 4,775,964, the subject matter of which is incorporated by reference as if fully set forth herein, or may comprise a liquid crystal display, such as that indicated by reference  20  and as illustrated in the figures. As would be readily known to those skilled in the art, use of one or more display hands permits for the display of information in an “analog” manner, while use of a liquid crystal display permits the display of information in a “digital” manner. 
   Also, while a specific embodiment of the present invention is that the wearable electronic device is a wristwatch, the present invention is not limited thereby and may be in the form of and/or have functionality related to for example and not limitation, altitude, temperature or compass measurements, barometric pressure, a heart rate display, blood pressure (and/or combinations thereof), the display of tide information, sunset information, moon phases, medical information such as when medicine should be taken and how many pills at each time interval or any other information that could be displayed on a liquid crystal display, such as a counter/timer or any one of additional parameters such as water pressure, water depth and oxygen left in a diver&#39;s tank (i.e. a diver&#39;s watch); object finder (i.e. to find one&#39;s car or way back to a starting location); blood/sugar levels (a glucometer); speed and distance (a runner&#39;s watch); and any combination of the foregoing, all of which may be in addition to or in the absence of conventional timekeeping functionality. 
   In accordance with the present invention, device  10  also comprises an illumination assembly, generally indicated at  30 , within casing  15 .  FIGS. 1 and 2  best illustrate the specifics of illumination assembly  30 . 
   In particular, illumination assembly  30 , comprising an electroluminescent assembly generally indicated at  40 , is preferably mounted (e.g. coupled) in casing  15 , and protected from dirt, dust and/or water by known sealing methodologies and construction. Electroluminescent assembly  40 , after accounting for all the layers as more particularly defined herein, has a bottom surface  42  and a top surface  44 , with bottom surface  42  in facing alignment with display assembly  20 . 
   Illumination assembly  30  also comprises a translucent ink/film layer  50 . Layer  50  also has a bottom surface  52  and a top surface  54 , wherein the bottom surface  52  is positioned in facing alignment with the top surface  44  of electroluminescent assembly  40 . Additionally, in a preferred embodiment, top surface  54  of translucent ink/film layer  50  has indicia, such as surface indicia  56 , thereon. In a preferred embodiment, surface indicia  56  is printed on translucent ink/film layer  50 , but depositing it on layer  50  can also be by painting and/or silk-screening by way of example and not limitation, using conventional techniques well known in the art. Examples of such surface indicia contemplated by the present invention can be terms to facilitate use of the device, such as but not limited to: “MODE,” “SET/RECALL,” “STOP/RESET” and “LIGHT” just to name a few. Additionally, the indicia could comprise other graphics, patterns or decorations or ornamentation, such as the flowers indicated by reference numeral  57  and illustrated in  FIGS. 3-5 . Additionally, the indicia could also be provided (e.g. embedded) within ink/film layer  50  by known processing techniques such that it is illuminateable as disclosed below. 
   Illumination assembly  30  further comprises a lens  60 , which is in facing alignment with top surface  54  of translucent ink/film layer  50 . Lens  60  is preferably clear (i.e. made of glass or plastic) to ensure good visibility of dial assembly  20  and surface indicia  56 . Ink/film layer  50  could be assembled with or applied to lens  60  either before or after lens  60  has been mounted and/or sealed within casing  15 . 
   As constructed, upon illumination of electroluminescent assembly  40  and more technically speaking, upon energizing of an EL layer  46  in electroluminescent assembly  40 , visibility of the indicia, whether embedded or surface indicia  56 , is facilitated. 
   Also, electroluminescent assembly  40  could be mounted with the module  15 , or mounted with ink/film layer film  50 , or mounted directly with lens  60  wherein ink/film layer  50  has been applied to the surface of the lens  60 . 
   Yet further, ink/film layer  50  could be multilayered or designed to create three (3) dimensional patterns, decorations and/or graphics to create visual depth or layering effects for enhanced aesthetics. 
   To energize EL layer  46 , well known circuitry can be implemented. For example, U.S. Pat. No. 4,527,096, the subject matter of which is incorporated by reference as if fully set forth herein, describes a suitable driving circuit for energizing EL layer  46 . Reference numeral  70  generally indicates the controller/circuitry means for such functions as timekeeping or other functionality to achieve the objectives set forth above (e.g. heartrate monitoring/display, etc.), along with the controller and driving circuitry for illumination of electroluminescent assembly  40 . Batteries and/or another suitable power source, while not shown, is contemplated, and its electrical coupling to a suitable drive circuit is believed to be well-known to those skilled in the art. A pusher  75 , operatively coupled to controller/circuitry  70 , is provided to selectively initiate the illumination of at least electroluminescent assembly  40 . 
   As illustrated, in  FIG. 2 , the preferred embodiment provides for the positioning of the electrical circuitry and power source for electroluminescent assembly  40  to be within module  15 . As such, wires and/or other electrical connections (e.g. pads, traces, etc.) can be used to electrically couple the driving circuit to electroluminescent assembly  40 . For example,  FIG. 1  illustrates the use of connectors  80  for providing the electrical coupling to electroluminescent assembly  40 . 
   Although not material to the present invention but to distinguish the inventive features from the conventional use of EL technology,  FIG. 2  illustrates the incorporation of a backlighting arrangement, also comprising an EL assembly, generally indicated at  85 . The layering of such an EL assembly is both well known to those skilled in the art and non-material to the present invention. A plurality of additional layers, such as polarizing films  21  and  22 , a retardation film  23  a cholesteric liquid crystal polymer sheet  24  and/or a translucent light absorbing layer  25  may also be provided or eliminated as the case may be and as would be well understood by one skilled in the art. 
     FIG. 3  shows device  10  using the construction set forth in  FIGS. 1 and 2  during normal lighting conditions (e.g. showing an example of how the indicia may be all or partially hidden during such normal lighting conditions) while  FIG. 4  illustrates the construction set forth in  FIGS. 1 and 2  during an illumination of assembly  40  during low lighting conditions. Specifically, it can be seen that illumination of EL layer  46  provides for the illumination of the indicia, whether surface indicia  56  or embedded indicia. As a non-material feature of the invention, display  20  can be a negative display (light segments on a dark background) or a positive display (dark segments on a light background). 
   It will thus be seen that the present invention is both patentably different from and a significant improvement over known devices. Specifically, the present invention provides a unique way to illuminate indicia provided, for example, in or on a translucent ink/film layer that is above display  20 . The present invention provides at the least, increased functionality, ease of use and enjoyment of the device. 
   While the invention has been particularly shown and described with respect to preferred embodiments thereof, it will be understood by those skilled in the art that changes in form and details may be made therein without departing from the scope and spirit of the invention. 
   Lastly, the preferred embodiment of the present invention is incorporated into a timepiece and a wristwatch in particular. The electronic device thus being a timepiece such as a wristwatch will thus comprise other features and parts, omitted herein for purposes of brevity. Also, the use of conventional references such as “top” and “bottom” are used only for ease of disclosing the present invention and are not intended to limit the scope thereof. The spacing shown between layers and/or the relative size of the layers in  FIGS. 1 and 2  are merely for convenience and do not represent any specific dimensions.