Patent Publication Number: US-2006000128-A1

Title: LED sign with continuous illumination effect

Description:
BACKGROUND OF THE PRESENT INVENTION  
      1. Field of Invention  
      The present invention relates to a LED (Light Emitting Diode) sign, and more particularly to a LED sign with continuous illumination effect which is capable of forming a line of light source from a plurality of LED illuminators for highlighting particular characters, such as an advertisement sign.  
      2. Description of Related Arts  
      Illuminating devices are widely utilized to perform differing commercial or business tasks. For example, advertisements are highlighted by light boxes so that during night time people can be notified and attracted by sharp and colorful advertisements. Besides, neon signs are usually set up in front of shops showing the opening status of them.  
      There exist a handful of illuminating devices in the marketplace, the two most popular being neon lights and advertisement light boxes in that they are conveniently available in regular business equipment suppliers and that they can sustain prolonged usage without getting out of order frequently. However, these cannot be taken to mean that they are free from disadvantages. In fact, some people are actually forced to tolerate those disadvantages and continue using them simply because they cannot find suitable alternatives.  
      A major disadvantage of conventional light boxes and neon lights is that they generate a large amount of heat while operating. Not to mention safety problem resulting from such heat, this large amount of heat itself represents a serious waste of large amount of energy which in turns reflects in unnecessary yet inevitable rise of the user&#39;s operating cost. Thus it comes to a lose-lose situation that the user pays higher for more serious loss of natural resources (electricity) without gaining any extra economic profit.  
      Another disadvantage is that conventional neon light or fluorescent light box is extremely fragile to physical impact. Thus, one has to put extra care in transporting the neon lights or the light boxes in order to prevent accidental damage on the part of them. This not only increases the cost of handling such products, but also present a potential risk to those handling or purchasing the products.  
      As a matter of fact, engineers are eager to seek alternatives for those conventional neon lights and advertisement light boxes. For example, they have thought of using LEDs for generating light to replace conventional neon lights and fluorescent lamps. However, there exist some inherent disadvantages for using LEDs. For example, despite the fact that LED is more long-lasting and economically more efficient, light from each particular LED is not generally strong enough for highlighting an advertisement or business signs. As a result, there exist some LED light boxes which comprise a plurality of LEDs electrically connected with each other to generate sufficient amount of illumination as a whole. However, as each LED represents a single point source of light, each light box eventually comes up with a plurality of discrete light sources and the overall illumination effect is far from satisfactory. Thus, the problem of how to convert what is originally discrete single points of light source to a continuous line of light source is a pressing problem for engineers.  
     SUMMARY OF THE PRESENT INVENTION  
      A main object of the present invention is to provide a LED sign which is capable of forming a uniform line of light source from a plurality of LED illuminators for highlighting a particular character, such as an advertisement sign.  
      Another object of the present invention is to provide a LED sign comprising at least one light guider for forming an illumination channel which accumulates light from a plurality of LED illuminators to form a continuous illumination effect for highlighting a predetermined character, such as a particular advertisement sign.  
      Another object of the present invention is to provide a LED sign comprising at least a figure sign of a predetermined color and aesthetic pattern so that it may either be highlighted by the LED illuminators to form the continuous illumination effect, or, where the LED illuminators are not lit up, arranged to display a particular character by virtue of its own color and aesthetic pattern without the lighting from the LED illuminators. In other words, the particular figure sign, such as the advertisement, may be used anytime with or without the LED illuminators lighting.  
      Another object of the present invention is to provide a LED sign which is simple in structure yet capable of delivering a continuous illumination light effect. In other words, the manufacturing cost and the ultimate selling price of the present invention must be minimized.  
      Another object of the present invention is to provide a LED sign which is durable, effective, efficient, and economical during operation.  
      Accordingly, in order to accomplish the above objects, the present invention provides a LED sign, comprising: 
          a figure sign shaped to form at least a character;     at least a light guider, which is shaped corresponding to the figure sign, having a plurality of light cavities and an illumination channel communicating with the light cavities, wherein the figure sign is supported by the light guider to optically communicate with the illumination channel; and     a plurality of LED illuminators spacedly disposed within the light cavity of the light guider for generating lights towards the illumination channel in such a manner that the lights are accumulated within the illumination channel to form a continuous illumination effect so as to project towards and to highlight the figure sign.        

      These and other objectives, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1A  is a perspective view of a LED sign according to a preferred embodiment of the present invention.  
       FIG. 1B  illustrates an alternative mode of the LED sign according to the above preferred embodiment of the present invention.  
       FIG. 2A  is a schematic sectional side view of the LED sign according to the above preferred embodiment of the present invention.  
       FIG. 2B  illustrates another alternative mode of the LED sign according to the above preferred embodiment of the present invention.  
       FIGS. 3A and 3B  illustrate the first alternative mode of the LED sign according to the above preferred embodiment of the present invention.  
       FIG. 4  is a second alternative mode of the LED sign according to the above preferred embodiment of the present invention.  
       FIGS. 5A and 5B  illustrate third alternative mode of the LED sign according to the above preferred embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
      Referring to  FIG. 1A ,  FIG. 1B  and  FIG. 2A ,  FIG. 2B  of the drawings, a LED sign according to a preferred embodiment of the present invention is illustrated, in which the LED sign comprises a figure sign  10 , at least one light guider  20 , and a plurality of LED illuminators  30 .  
      The figure sign  10  is shaped as forming a particular character having a predetermined light transmisivity and color. For example, the figure sign  10  may be embodied as a ‘O’ character in which it may be coated with a particular color for particular purpose, such as for use in a particular advertisement campaign.  
      The light guider  20  is shaped corresponding to the character sign  10 , wherein it is overlappedly supported on a central portion of a front side of the light guider  20  and optically communicated with the illumination channel  21 . Moreover, the light guider  20  further has a plurality of light cavities  23  for receiving the LED illuminators  30 .  
      The plurality of LED illuminators  30  are spacedly disposed within the light cavity  23  of the light guider  20  for generating lights towards the illumination channel  21  in such a manner that the lights so generated are accumulated within the illumination channel  21  so as to form a continuous illumination effect and projected towards the figure sign  10  for highlighting that particular character, such as the character ‘S’.  
      The light guider  20  comprises an elongated solid member made of translucent materials to form the illumination channel  21  in a solid manner such that when the LED illuminators  30  project the light towards the illumination channel  21 , the light are evenly diffused along the illumination channel  21  to form the continuous illumination effect.  
      Therefore, the illumination channel  21  is a physical passageway which has a predetermined light transmisivity so as to allow light passing therethrough. Referring to  FIG. 2  of the drawings, the illumination cavities  23  are indently formed along a rear side of the light guider  20  to receive the LED illuminators  30  respectively, in such a manner that a head portion of each of the LED illuminators  30  is embedded on the rear side of the light guider  20  towards the figure sign  10 .  
      Each of the LED illuminators  30  is adapted to radiate light at an angle of approximately 120° frontwardly from a head portion of that LED illuminator  30 . According to the preferred embodiment, the head portion is arranged to directly face the illumination channel  21  such that a maximum intensity of light is propagated to the illumination channel  21  for forming the single line of light source to highlight the figure sign  10 .  
      The LED sign further comprises a supporting frame  40  having a displaying side that the light guider  20  is protruded therefrom to substantially support the light guider  20  in position, wherein the LED illuminators  30  are spacedly supported on the supporting frame  40  along the illumination channel  23  of the light guider  20 .  
      Each of the LED illuminators  30  are electrically connected with each other in the supporting frame  40  which is then electrically connected to a power source for lighting up the LED illuminators  30  through a power inlet provided on the supporting frame  40 .  
      The supporting frame  40  may be longitudinally extended to form an elongated structure wherein a plurality of light guiders  20  and figure signs  10  are protruded therefrom so as to form a large-scale advertising sign. For example, the advertising sign may be ‘OPEN’ or the likes, as shown in  FIG. 1  of the drawings.  
      Thus, the LED sign further comprises a control switch  60  provided on the supporting frame and electrically connected with the LED illuminators  30  for controlling an operation of the LED illuminators  30 . According to the preferred embodiment, the control switch  60  comprises a control box  61  mounted on a bottom portion of the supporting frame  40 , and an actuation string  62  operatively extended from the control box  61  in such a manner that it is capable of being pulled to alternatively turn on an off the LED illuminators  30 . In other words, a user is able selectively turn on or off the LED sign by slightly pulling the actuation sting  62 .  
      From the foregoing descriptions, it can be shown that when the LED illuminators  30  are connected to a power source, such as the external AC power source or a DC power source, they would be lit up and generate light in the illumination cavity  23  towards the illumination channel  21 . The light in the illumination channel  21  would then accumulate and form a line of light source projecting towards the figure sign  10 . The light would then pass through the illumination channel  21  to reach an outside of the light guider  20  through a front side edge portion thereof in such a manner as to highlight the figure sign  10 . The figure sign  10  may also be made to be light transmissible but having a light transmisivity different from that of the illumination channel  21 , in such a case, difference in the transmisivity would produce special light effect to the LED sign of the present invention. Ultimately, it is worth mentioning that the discrete LED illuminators  30  are arranged to generate a single line of light source for highlighting the figure sign  10 .  
      Accordingly, the figure sign  10  should be made of opaque material, and shaped and sized smaller than that of the light guider  20 , wherein when the LED illuminators are switched off, the figure sign  10  physically forms a display sign in a solid font manner, and when the LED illuminators  30  are switched on, the light within the illumination channel  21  forms the continuous illumination effect to encircle a surrounding edge of the figure sign  10  in a shaded font manner.  
      Furthermore, the figure sign  10  can be furnished with a particular pattern of light effect or aesthetical design such that even when the LED illuminators  30  are not in use, the figure sign  10  by itself would also present a complete visible sign, though without illumination.  
      Referring to  FIG. 3A  of the drawings, an alternative mode of the LED sign according to the preferred embodiment of the present invention is illustrated. According to the alternative mode, the light guider  20 ′ has two sidewalls  22 ′ forming two illumination cavities  23 ′ along two sides of the illumination channel  21 ′ respectively wherein the LED illuminators  30 ′ are spacedly disposed in the illumination cavities  23 ′ for generating light towards the illumination channel  21 ′. The light from the LED illuminators  30 ′ are internally reflected and accumulated within the illumination channel  21 ′ to form a continuous light effect projecting towards the figure sign  10 ′. Since the figure sign  10 ′ has a predetermined light transmisivity, the continuous light effect forms a single line of light source to highlight the figure sign  10 ′ in a continuous illuminating manner.  
      In order to enhance the light accumulation performance, the light guider  20 ′ further comprises two light reflecting layers provided on a rear wall of the illumination channel  21 ′ for intensifying internal light reflections therewithin. The light reflecting layer is preferably embodied as a silver layer coated on the rear wall of the light cavities  23 ′ respectively, wherein light from the LED illuminators  30 ′ would impinge upon the light reflecting layer and results in intense multiple reflections within the illumination channel  21 ′ to form the line of light source. Obviously, other kind of light reflectors layers, such as mirrors, which can also cause this reflection pattern within the illumination channel  21 ′, may be utilized as alternatives.  
      As a slight alternative of the first alternative mode, as shown in  FIG. 3B  of the drawings, the respective head portion of each of the LED illuminators  30 ′ may be mounted to face towards the front in the respective illumination cavity  23 ′, i.e. towards the figure sign  10 ′.  
       FIG. 4  illustrates a second alternative mode of the LED sign according to the above preferred embodiment of the present invention, in which case the light guider  20 ″ comprises an elongated hollow member made of translucent material to define the illumination channel  21 ″ therewithin and the light cavities along two sidewalls of the illumination channel respectively, such that when the LED illuminators project the lights towards the illumination channel, the light are evenly diffused along the illumination channel to form the continuous illumination effect.  
      In order to further enhance internal reflections inside the illumination channel  21 ″, the light guider  20 ″ further comprises two side reflectors  24 ″ provided on two sidewalls  22 ″ thereof in the light cavities  23 ″ respectively so as to substantially reflect those portions of light impinging on the sidewall  22 ″ back to the illumination channel  21 ″. As such, the line of light source forming in the illumination channel  21 ″ will be of improved coherence.  
      The two side reflectors  24 ′ are preferably embodied as two reflective mirrors or silver coatings from which the light can be substantially reflected back to the illumination channel  21 ′.  
      Referring to  FIG. 5A  of the drawings, a third alternative of the LED sign according to the above preferred embodiment of the present invention is illustrated, in which the light guider  20 A has a hollow member which communicates with the light cavity  23 A. The figure sign  10 A is made of opaque material, and shaped and sized smaller than that of the light guider  20 A, wherein when the LED illuminators  30 A are switched off, the figure sign  10 A physically forms a display sign in a solid manner, and when the LED illuminators  30 A are switched on, the light within the illumination channel  21 A forms the continuous illumination effect to encircle a surrounding edge of the figure sign  10 A in a shaded font manner.  
      Moreover, the two sidewalls  22 A of the light guider  20 A form two illumination cavities  23 A along two sides of the illumination channel  21 A respectively wherein the LED illuminators  30 A are spacedly disposed in the illumination cavities  23 A for generating light towards the illumination channel  21 A. Then, the light from the LED illuminators  30 A are internally reflected and accumulated within the illumination channel  21 A to form a continuous light effect projecting towards the figure sign  10 A. Since the figure sign  10 A has a predetermined light transmisivity, the continuous light effect forms a single line of light source to highlight the figure sign  10 A in a continuous illuminating manner.  
      As shown in  FIG. 5B  if the drawings, it is worth mentioning that each of the LED illuminators  30 A may be embodied as radiating light sidewardly from the head portion of that LED illuminator  30 A at an angle of approximately 120° so that although the LED illuminator  30 A is facing towards the figure sign  10 A in the respective illumination cavity  23 A, the light radiating therefrom would propagate sidewardly towards the respective sidewall  22 A and the illumination channel  21 A.  
      In order to further enhance internal reflections inside the illumination channel  21 A, the light guider  20 A further comprises two side reflectors  24 A provided on two sidewalls  22 A thereof in the light cavities  23 A respectively so as to substantially reflect that portion of light impinging on the sidewall  22 A back to the illumination channel  21 A. As such, the line of light source forming in the illumination channel  21 A will be of improved coherence.  
      The two side reflectors  24 A are preferably embodied as two reflective mirrors or silver coatings from which the light can be substantially reflected back to the illumination channel  21 A.  
      One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting.  
      It will thus be seen that the objects of the present invention have been fully and effectively accomplished. It embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.