Abstract:
LEDs are considered to be point light sources. Visible light provided by one or more light emitting diodes (LEDs) is passed through a light diffuser. The LEDs and diffuser are mounted inside a transparent or light-transmissive non-evacuated envelope and bulb. The light emitted from the bulb appears to originate from a filament used in conventional light bulbs rather than from a point light source.

Description:
FIELD OF THE INVENTION 
     The present invention relates to an artificially simulated incandescent filament suited for replicating the appearance of vintage carbon filament light bulbs. 
     BACKGROUND OF THE INVENTION 
     Conventional incandescent light bulbs heat a filament inside a glass bulb, which is at least partially evacuated. Such bulbs are able to create what is considered by many to be a soft amber glow, which is also considered by many to be suitable for mood lighting and visually appealing. Such characteristics are those of a glowing filament contained inside the glass bulb. 
     Conventional incandescent bulbs are used in both interior and exterior garden and patio lighting applications where their visible lighting characteristics are desired. As is well known, conventional incandescent bulbs waste a substantial portion of the electrical energy required to operate. They are also relatively expensive to manufacture. A need is thus considered to exist for a reduced-energy-consumption lighting device that can provide the visual lighting effects of prior art incandescent light bulbs and which is relatively inexpensive to manufacture. 
     SUMMARY OF THE INVENTION 
     Light-emitting diodes or “LEDs” and diffusers simulate the effect of conventional incandescent light bulbs. More particularly, a hollow bulb, which is at least partially light transmissive, houses one or more LEDs and one or more diffusers that appear to be suspended in the interior of the bulb volume while diffusing the point light source from the LEDs in order to simulate extended lengths of light such that an incandescent filament provides. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a faux filament light bulb assembly; 
         FIGS. 2-4  depict alternate embodiments of a faux filament light bulb assembly; 
         FIG. 5  is a perspective view of an installation application of the faux filament light bulb assembly; 
         FIG. 6  is an exploded view of the installation application shown in  FIG. 5 ; 
         FIG. 7  is a perspective view of a light string assembly comprising of the faux filament light bulbs; 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  is a perspective view of a faux filament light bulb assembly  100 . The faux filament assembly  100  is comprised of a light-transmissive bulb  102 , which is operatively coupled to a base  110 , also referred to herein as a secondary housing  110 . The bulb  102  encloses one or more light emitting diodes (LEDs)  104 . Light emitted from the LEDs passes through diffusers  106 . The light diffusers  106  are light diffusive. 
     The housing  110  contains electrical devices that connect terminals or leads  108  of LEDs to wires  112 , which are in turn connected to an electrical power source, not shown. The LEDs support, or are placed into, one or more light diffusers  106 , which cover or encapsulate at least part of the LED&#39;s light-emitting surfaces. In some embodiments, the base  110  contains circuitry to convert common A.C. voltage to D.C. voltage for the LEDs. Such circuitry is well known to those of ordinary skill. Description of such circuitry is therefore omitted for brevity. In some embodiments, the base  110  contains electronic components, such as circuit boards and resistors, in order to supply the appropriate electricity for the LEDs. Such circuitry is well known to those of ordinary skill. Description of such circuitry is therefore omitted for brevity. 
     The point light source of the LEDs  104  is transmitted into a diffuser  106  and thereafter diffused along the length  107  of the diffuser  106 . The light from the LED that is diffused simulates or approximates the diffuse lighting effect provided by a conventional incandescent bulb/filament. 
     The leads  108  are actually comprised of a positive lead  109  and a negative lead  111 . One of them is also considered herein to be an anode lead while the other is considered herein to be a cathode lead. As shown in  FIG. 1 , the leads  108  support the LEDs  104  above the top surface  113  of the housing  110  by a distance  117  substantially equal to the length of the leads  108 . Elevating the LEDs  104  and their associated diffusers  106  above the top surface  113  aids the simulation of a conventional bulb but it also facilitates the broadcast of light energy from the LEDs  104 . In an alternate embodiment not shown, wherein the orientation of the housing  110  and bulb  102  are “reversed” in order to have the bulb assembly  100  suspended from a ceiling from the housing  110 , the leads  108  suspend the LEDs  104 . 
     The LEDs  104  are spatially separated from each other in the bulb  102 , the distance  115  between them being a design choice selected to provide among other things, different simulated filament lengths to visibly balance different bulb  102  shapes. Spatial separation of the LEDs can be accomplished and adjusted by bending the leads  108 , the distal ends  119  are rigidly fixed in the housing  110 . 
     As stated above, the bulb  102  is light transmissive. As used herein, the term “transmissive” should be construed to mean that at least some of the visible light emitted from the LEDs  104  is able to pass through the bulb housing. 
     The term “diffuse” is considered herein to mean, not concentrated or not localized. “Diffusive” should therefore be construed to mean tending to diffuse. Since “diffuse” means not concentrated or not localized, diffusive light, i.e., light from the LEDs  104  that is diffused by the diffuser  106 , should be construed to include light that does not appear to come from a point source but instead appears to come from a somewhat “spread-out” source, or a non-localized, or not concentrated source. Light from the LEDs  104  that is diffused will thus appear to make the diffuser  106  as if it is entirely illuminated, and from inside the diffuser  106 , and not from a localized point as does the light from a non-diffused LED. 
       FIG. 2  is a perspective view of an alternate embodiment of the faux filament light bulb assembly  200 . The assembly  200  is comprised of a light transmissive bulb housing  202  that encloses three LEDs  204 , each of which is at least partially enveloped or encapsulated in a light diffuser  206 . The lead wires  208  of the LEDs  204  are operatively coupled to a secondary housing  210 . The housing  210  contains and provides electrical connections between the lead wires  208  of the LEDs  204  and wires  212  that can be connected to an electrical energy source not shown. 
     As with the faux filament bulb  100  shown in  FIG. 1 , the housing  210  shown in  FIG. 2  provides a base to which the LEDs  204  can be mounted. Since the diffuser  206  is attached to the LEDs  204 , the housing  210  also supports the diffuser  206 . The point light source from the LEDs  204  is transmitted and diffused throughout the diffuser  206  in order to provide substantially uniform light in order to simulate the light effect of an incandescent filament. The positive and negative leads  208 , also known as the anode and cathode, are used to suspend the LEDs  204  in the interior bulb volume in order to give a separation distance for the light source from the secondary housing  210  which is common for incandescent type light bulbs. Note that the LED leads  208  described can also be an alternate substantially rigid conductive component used to transmit electricity to the LEDs  204 . 
       FIG. 3  is a perspective view of an alternate embodiment of a faux filament light bulb assembly  300 . In  FIG. 3 , the assembly  300  is comprised of a light transmissive bulb housing  302 , operatively coupled to a base or secondary housing  310 , which contains the electrical connections and mounting structure  313  to hold or mount the LEDs  304 , which support diffusers  306 . In  FIG. 3 , the diffusers  306  are elongated, light-transmissive cylinders  315  having two opposing ends  317  and  319  into which LEDs  304  are inserted and which frictionally-engage the interior surface of the cylinder  315 . The point light source from the LEDs  304  is transmitted through-out the length  321  of the cylinder  315  and diffused throughout the diffusers  306  to provide substantially uniform light, which approximates or simulates the light effect of an incandescent filament. The leads  308  of each diode  304  support the LEDs  304  above the housing  310  and from other diodes  304  to provide a separation distance  323  for the light source from the secondary housing  310 . 
       FIG. 4  is a perspective view of an alternate embodiment of a faux filament bulb assembly  400 . In  FIG. 4 , the assembly  400  is comprised of a light transmissive bulb housing  402 , operatively coupled to a base or secondary housing  410 , which contains the electrical connections. In this embodiment, a substantially rigid secondary component  414  is used to support at least a portion of the mass of the LEDs  404  and diffuser  406 . The secondary support structure  414  reduces or eliminates the need for the LED leads  408  to support the LEDs  404  and diffuser  406 . 
       FIGS. 5 and 6  depict a faux filament light bulb installation assembly  500  comprising of a faux filament light bulb assembly  502  and a receptacle assembly  504 . In  FIG. 6 , the faux filament light bulb  502  is provided with a standard screw-type base  608 . The base  608  includes an A.C. to D.C. converter, filter and current limiting resistors to enable the bulb assembly  500  to be energized by conventional A.C. voltages used to energize conventional light bulbs. The receptacle assembly  504  is provided with a socket  609  with conventional threads  611  that receive a standard screw-type base  608 . Conventional electrical connections on the base  608  and in the socket  609  enable the bulb assembly to be used in a standard home light bulb socket. In an alternate embodiment, the receptacle assembly is provided with an A.C. to D.C. converter, filter and current limiting resistors to enable the bulb assembly  500  to be energized by conventional A.C. voltages used to energize conventional light bulbs. 
       FIG. 7  is a perspective view of a light string assembly  700  comprising of a plurality of faux filament light bulbs  702  connected in series to either an A.C. or D.C. power source, not shown. In instances where the bulbs  702  are powered by A.C., an A.C. to D.C. converter is provided in at least one of the bulbs  702  or the receptacles  705  into which each bulb is attached. 
     The diffusers are preferably embodied as a substantially optically clear material, such as acrylic, wherein the exterior surface where light is diffused is textured to allow even distribution of light along their lengths. Faceted surfaces as well as openings along the length of the diffuser can also be employed to provide different effects. As depicted in the figures, the diffusers having openings  317  and  319  into which the substantially cylindrical lens body of an LED is inserted and frictionally engaged. The diffusers can also be directly molded to the LEDs or the LEDs can be custom made with the diffusers serving as the lens body of the actual LED at manufacture. 
     The bulb housing is preferably made from glass or plastic, but any substantially light transmissive material can be used for manufacture. The bulb housing can also be of any shape, but the scope of the invention implies that the bulb housing will resemble that of an incandescent light bulb which are typically a classic bulb shape or cylindrical in design. Unlike conventional incandescent bulbs, the bulb housing described above does not require any evacuation. The faux filament bulbs are thus considerably less expensive to manufacture 
     The bulb housing is preferably substantially clear to simulate the effect of a vintage type carbon filament light bulb, but use of a textured or frosted bulb in combination with the LEDs and diffusers described above can be employed as long as a partial effect of the extended lengths of light created by the LEDs and diffusers is visible. 
     The use of a transparent holographic film applied to the bulb housing can also be employed in order to further extend the diffused lengths of light on the exterior surface of the bulb housing. Transparent holographic films contain embedded patterns which allow for the distortion of light passing through the material to create visual effects on the material. An application of this type of material directly to the bulb housing would allow the aforementioned visual effects to accentuate the visual effects created by the LEDs and diffusers. 
     Assembly of any of the aforementioned components can be accomplished by numerous methods employing integrated mechanical features or by use of adhesives, solder, potting processes, etc. It is assumed that housings are snapped together and other components are captured by integrated features while electrical connections are made by standard connectors and solder. 
     The foregoing description if for purposes of illustration. The true scope of the invention is set forth in the following claims.