Abstract:
A light source enhancing lens assembly  10  has a carrier  20,  a light source  30  carried by the carrier  20,  a first lens  40  which refracts and diffuses light emitted from the light source  30  and a second lens  70  to defocus and further distribute the light emitting from the first lens  40.  The light source  30  is inserted into the first lens  40,  so that light from the LED is refracted within a first bore  48  and diffused by a frosted first outer surface  60  of the first lens  40.  The first lens  40  inserts into a second bore  40  of the second lens  70.  Light from the first lens  40  is further defocused by a series of parallel, spaced apart lens sections  82  located on the second outer surface  78  of the second lens  70.

Description:
BACKGROUND OF THE INVENTION 
     I. Field of the Invention 
     The present invention relates generally to lighting devices. More particularly, the present invention relates to lenses for lights. 
     II. Description of the Related Art 
     Light emitting diodes (LEDs) consume considerably less power than incandescent light bulbs, making their use highly desirable. To increase the luminosity of LEDs, lenses are placed in front of them, which focuses the light into a beam that is essentially perpendicular to the LED junction base. Inevitably, light dispersion from the LED is decreased, which limits the use of LEDs to specialized illumination applications. 
     LEDs are readily available in the market place. Three of the “standard” LEDs are a basic LED, a bright LED and an ultra bright LED. The basic LED has an output level between 1.5 to 10 mcd and a viewing angle from 75 to 100 degrees. The bright LED has an output level between 10 to 50 mcd and a viewing angle from 50 to 75 degrees. The ultra bright LED has an output level between 50 to 2,000 mcd and a viewing angle from 18 to 60 degrees. All of these LEDs are useful for a focused light beam application that ranges from situations where there is no ambient light situations to those in daylight. 
     Recent developments in LED technology have resulted in the availability of “super high intensity” LEDs. Super high intensity LEDs are commonly used in cluster applications to replace standard “spot” lamp applications and traffic warning devices. The output level is between 6,000 to 20,000 mcd and the viewing angle is a very narrow 4 to 8 degrees. Yet, use of this powerful LED is still limited to focused light applications due to its narrow viewing angle design. A significant problem occurs when a LED is used and the viewer is outside the narrow range of its beam of light Intensity drops off precipitously. 
     Use of devices such as fresnel lenses or reflectors can assist the human eye in detecting light emitted by an LED over wider viewing angles. However, use is still limited to relatively focused light applications designed for viewing directly in front of the LED. 
     Various attempts have been made to broaden the LED light beam. For example, a self-powered ornamental lighting device is described in U.S. Pat. No. 4,866,580 by Blackerby. This device includes a LED encased within a bulb. This bulb appears to have no particularly special refracting nor diffusing characteristics. In another embodiment, a metal foil reflector is used to reflect light emitted from the LED. 
     Similarly, German Patent Number 41 20 849 A1 by Sitz describes an ornamental lighting apparatus using an LED and a bulb enclosure having the characteristics of a candle flame. Like Blackerby above, this member also appears to have no particularly special refracting nor diffusing characteristics. 
     U.S. Pat. No. 4,965,488 by Hili describes a light-source multiplication device having a planer lens with multiple facets. An LED emits light toward the planer lens. Surrounding the LED is a reflector to reflect any laterally emitted light from the LED toward the planer lens. Light beams transmitted by the planer lens are parallel to one another. 
     An LED lamp including a refractive lens element is described in U.S. Pat. No. 5,174,649 by Oilstone. The lamp includes one or more LEDs that illuminate the refractive lens element, which has hyperboloids and facets, to give the effect of its being fully illuminated. However, the lighting effect from the lens remains in a narrow viewing angle and in front of the LED. Once the viewer out of the viewing angle, the effect will not readily be apparent. 
     As described in U.S. Pat. No. 5,311,417 issued to Hey, an Illuminative Sucker &amp; Decorative String Thereof comprises a sucker having a sucker cup portion and a back portion formed on a back portion of the sucker cup portion, a lamp socket secured to the back portion of the sucker and a lamp inserted in the lamp socket. Both the lamp socket and the sucker may be made of translucent or transparent materials. The sucker cup portion has a cavity formed in the cup portion to enable it to be adhered to a flat surface. Once the lamp is lit, the lamp projects light beams toward the back portion of the sucker, especially when the lamp is an LED, causing the back portion to glow unidirectionally. As shown and described, the lamp socket is not a lens that refracts or diffuses light, but is provided to contain the lamp and permit the lamp to emit a unidirectional light beam toward the back portion of the sucker. This is further demonstrated by the shade fitted to the sucker so that light emitted from an incandescent bulb is totally projected onto the back portion. 
     Lemelson, in U.S. Pat. No. 2,949,531, describes an Illuminated Highway Marker. The marker comprises a base having a rigid housing secured thereto and an electric lamp disposed within the housing. Surrounding the housing is a cover of a transparent plastic which is flexible but thick enough to protect the rigid housing from impact. Although the housing is rounded to one hundred eight degrees of the body diameter to form a convex apex, the apex is not hyperbolically-shaped. As a result, light emitted from an LED striking the apex would not refract and diffuse to illuminate the total outside surface of the housing. The cover has the same shape as the housing and is not capable of defocusing and omnidirectionally distributing the light emitted from an LED. 
     SUMMARY OF THE INVENTION 
     According to its major aspects and broadly stated, the present invention is a light assembly that includes a carrier, a light source carried by the carrier, and a lens system. The lens system further comprises a first lens to refract and diffuse light emitted from the light source and a second lens to defocus and further distribute the light transmitted by the first lens. The light source is preferably a super high intensity LED, which is inserted into a bore formed in the first lens. Light from the LED is refracted by the first lens and diffused by its frosted outer surface. The first lens is itself inserted into a bore formed in the second lens. Light from the first lens is further defocused and diffused by a series of linear lens sections located on the outer surface of the second lens. 
     The ability to evenly distribute light over the surface of a single LED is a major advantage of the present invention. In order to evenly distribute the light, two lenses work in conjunction with each other to refract, diffuse and distribute light from the source. 
     Another important advantage of the present invention is the ability of the outer lens to take on an ornamental shape. This advantage allows the present lens assembly to be used in various novelty items, such as candles and jack-o-lanterns. In addition to taking on ornamental shapes, the lens assembly can carry a fluorescent material so that the lens assembly radiates absorbed light. 
     Other features and their advantages of the invention will become apparent from the following description taken in conjunction with the accompanying drawings showing the preferred embodiment of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an elevation view of a light assembly made in accordance with the present invention; 
     FIG. 2 is an exploded, elevation view of the lens assembly and light source; 
     FIG. 3 is an exploded, sectional view of the lens assembly taken along Line  3 — 3  of FIG. 2; 
     FIG. 4 is a sectional view of the first lens taken along Line  3 — 3  of FIG. 2 showing the refraction of light within the first lens; 
     FIG. 5 is a sectional view of the first lens taken along Line  3 — 3  of FIG. 2 showing the refraction of light emitting from an apex; and 
     FIG. 6 is an elevation view of the lens assembly and light source showing the diffusion of light by the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     For a fuller understanding of the nature of this invention, reference should be made to the following detailed description taken in connection with the accompanying drawings. In the drawings like reference numerals designate corresponding parts throughout the several figures. 
     FIG. 1 of the drawings illustrates a partial elevational view of an LED light assembly, generally illustrated by reference numeral  10 . A carrier  20  provides a platform for removably supporting a lens assembly  25  and a light source  30 . A suitable light source  30  can be any light generating means, including an incandescent bulb, but is preferably a light emitting diode (LED). A super high intensity LED is most preferred because of its extreme light brightness and the color or wavelength band it emits. Part of this band and light output level is irritating to the eyes and draws attention to the light source. Additionally, carrier  20  provides support for a diffusing and refracting internal first lens  40  and a complex, external second lens  70 , that, together with light source  30  and carrier  20 , comprise light assembly  10 . 
     Referring now to FIGS. 2 and 3, first lens  40  is used to soften and better colorize the output of light source  30 . First lens  40  refracts light for the better distribution. First lens  40  is an elongated cylindrically-shaped member made of a highly dense, light transmissive material, such as glass or transparent plastic, preferably, acrylic. Because first lens  40  interacts directly with light source  30 , it is important for the light transmissive material of first lens  40  to have the property of low light absorptivity. This property enables first lens  40  to transmit nearly all the light emitted from light source  30  even when the light is reflected repeatedly within it. 
     With continuing reference to FIGS. 2 and 3, first lens  40  has a cylindrical body  42 , a first end  44  and a second end  46 . Since body  42  is cylindrically-shaped, the longitudinal axis of first lens  40  runs between first and second ends  44  and  46 . At first end  44  is a first bore  48  which extends into cylindrical body  42  and is centrally disposed within body  42  along its longitudinal axis. First bore  48  has a diameter and length sufficient to receive light source  30  within first bore  48 . Preferably, first bore  48  is dimensioned and shaped to receive light source  30  with little clearance. Within first bore  48  are a first bore wall  50  and a first bore end  52 . First bore end  52  defines a hemispherically-shaped, first concave surface  54 . First bore wall  50  has a first bore inner surface  56 . First concave and bore inner surfaces  54  and  56  may be lusterless or “frosted” so as to better diffuse the light entering body  42 . In the preferred embodiment, first concave and bore inner surfaces  54  and  56  are smooth. At the second end  46 , first lens  40  has a generally-hyperbolic shape except for an outwardly pointed apex  58 . First lens  40  has a first outer surface  60  and a first lens inner surface  62 , both of which extend from first end  44  to second end  46 , and first outer surface  60  is frosted or distressed, or a combination of both. Distressing first outer surface  60  increases the external surface area of first lens  40 . At second end  46 , first lens  40  is generally hyperbolically-shaped to effect distribution of the narrow band of light that emanates from the light source  30 . To provide proper distribution of light, the light needs a reflective surface that is hyperbolic in shape to cause the refraction of light over as much of first outer surface  60  as reasonably possible. 
     As shown in FIGS. 2 through 5, second end  46  of first lens  40  is hyperbolic in shape, and this hyperbolic shape is important to the distribution of the narrow band of light that emanates from the LED disposed within first bore  48  of first lens  40 . With particular reference to FIG. 4, the very narrow, super high intensity light beam emanating from light source  30 , characterized in FIG. 4 as lines labeled as A, strikes the hyperbolically-shaped, curved first lens inner surface  62  at the second end  46  of first lens  40 . Because of the high clarity of the light transmissive material, first lens inner surface  62  at the second end  46  of first lens  40  appears to be a mirrored surface from inside first bore  48 , thus reflecting the very narrow, emitted light beam A into a widely and evenly distributed light beam A that strikes all of first lens inner surface  62  of first lens  40 . Frosted first outer surface  60  diffuses this captured light while softening the harshness of the original light and causing first lens  40  to appear to glow from all viewing angles not blocked by carrier  20 . Distressing first outer surface  60  increases the overall surface area of first lens  40  which, in turn, increases the light distribution and further lowers the sharp intensity of the light output of light source  30 . 
     Once the light has been softened and widely distributed by first lens  40 , its focus is de-enmphasized by second lens  70  to further soften it and to enhance the distribution of the light by passing it through a special complex lens group that is shaped for a specific purpose, and for aesthetics dictated by the target design. 
     Referring now to FIGS. 1 through 3, second lens  70  has a generally convex-shaped, cylindrical body  72  made of a solid, high-density, light transmissive material. Although not required, the light transmissive material used for second lens  70  is preferably the same as the material used for first lens  40 . Second lens  70  has a first end  74 , a second end  76  and a second outer surface  78 . Disposed between the first and second ends  74  and  76  of second lens  70  is convex-shaped cylindrical body  72  with a second lens longitudinal axis co-axial with the longitudinal axis of first lens  40 . At the first end  74  is a second bore  80  which extends into body  72  and is centrally disposed along the second lens longitudinal axis thereof. Second bore  80  has a diameter and length sufficient to receive first lens  40  therein. Preferably, second bore  80  receives first lens  40  and has a compatible shape to that of first lens  40  so that second bore  80  matingly and removably receives the first lens  40  with little radial clearance. If desired, second bore  80  can have a length along the second lens longitudinal axis that is sufficient to allow movement of the lens  70  for variable focus. The preferred embodiment of the convex shaped, cylindrical body  72  shown in the drawings is in the form of an ornamental candle flame. Cylindrical body may be formed in other ornamental shapes, such as a jack-o-lantern. 
     Again referring to FIGS. 1 and 2, protruding from the second outer surface  78  are a plurality of convex, roughly parallel lens sections  82  of predetermined depth and width extending from first end  74  to second end  76  of convex-shaped cylindrical body  72 . Concentric lens sections  82  are formed on curved second outer surface  78 . Although the shape of second lens  70  as illustrated is design specific, its shape remains consistent with the functional goals of light system  10 . Even though second lens  70  is not limited to a specific number of concentric lens sections  82 , the preferred embodiment has at least 20 concentric lens sections  82  which are spaced-apart from each other but equidistantly spaced. Between each of the concentric lens sections  82  is a face  84  which is flat. 
     With continuing reference to FIGS. 1 and 2, concentric lens sections  82  have a focal length such that frosted first outer surface  60  of first lens  40  is significantly magnified, and unfocused. This combination softens the light from light source  30 , and allows for maximum light dispersion and an even distribution of the light, while producing a “halo” or glowing effect on second outer surface  78  of second lens  70 . Each concentric lens section  82  on second outer surface  78  of second lens  70  distributes the light. The internal shape of second lens  70  reflects some of the light passing through it back inside second lens  70  where it strikes first outer surface  60  of first lens  40 , further causing more even light distribution on first outer surface  60 . 
     As shown in FIG. 3, second bore  80  has a second bore wall  86  and a second bore end  88 . Comparable to first lens  40 , second bore end  88  is rounded to form a hyperbolically-shaped, second concave surface  90 . Within second bore  80 , second bore wall  86  has a second inner surface  92 , and second inner and concave surfaces  92  and  90  are preferably smooth. On the other hand, by using frosted second inner and concave surfaces  92  and  90 , the diffraction effect is greater. A mounting rim  94  is provided at the first end  74  of the second lens  70 . Mounting rim  94  removably engages carrier  20 . 
     Referring now to FIGS. 3,  5 , and  6 , depending on the distance of apex  58  of first lens  40  to second bore end  88 , the intensity, focus and second end  76  light distribution over the second outer surface  78  of second lens  70  will change. If second end  76  of second lens  70  is to be bright, then the focus needs to be sharp. If more even light distribution over second outer surface  78  is desired and second end  76  of second lens  70  is not to be bright with respect to second outer surface  78 , then the focus of first lens  40  to second bore end  88  of second lens  70  should be de-emphasized, i.e. made less sharp. Focus is controlled by the distance between first lens  40  and second bore end  88  of second lens  70 . The focus stems from a relationship between the distance between first and second lenses  40  and  70  and the LED light aperture. This relationship will also vary depending on the use and shape of second lens  70 . The hyperbolically-shaped second end  46  of first lens  40  reshapes the light beam B at that area into an inverted cone, as shown in FIG.  5 . The closer apex  58  of first lens  40  comes to opposing second bore end  88  of second lens  70 , the narrower the light beam B emanating from second end  46  of first lens  40  becomes, thus intensifying its output through concentration and narrower surface area dispersement. Conversely, as apex  58  of first lens  40  is pulled away from second bore end  88  of second lens  70 , the wider the light beam B emanating from second end  46  of first lens  40  becomes. Consequently, as shown in FIG. 6, the wider light beam C covers more of second outer surface  78  of second lens  70 , yields a less intense light output from second end  46  of first lens  40 , and additionally illuminates more of second outer surface  78  of second lens  70  because of the internal refraction of the light beam C within second lens  70 . 
     Lenses  40  and  70  may be coated or formed from a fluorescent material to appear to glow after exposure from light source  30 . Preferably, lenses  40  and  70  have fluorescent material applied in one of three locations: coating first outer surface  60  of first lens  40 , coating second inner surface  92  of second lens  70 , and injecting a phosphoric dye into the material from which first lens is formed. 
     In use, second lens  70  slidably receives first lens  40  at second bore  80  which, in turn, receives light source  30  in first bore  48 . Lens assembly  25  and light source  30  are fitted to carrier  20 . First lens  40  is fully inserted into second bore  80  such that first end  44  of first lens  40  is adjacent to first end  74  of second lens  70 . With Light source  30  energized, second lens  70  further defocuses the light emitting from first lens  40  and enhances light distribution by magnification through concentric lens sections  82 . The light is further distributed by refraction within second bore  80  as in first lens  40  and first bore  48 . The combination of first lens  40  and second lens  70  softens the light from light source  30 , and allows for maximum light dispersion and even distribution of the light, while producing a “halo” effect on the secend outer surface  78  of second lens  70 . 
     Various modifications may be made of the invention without departing from the scope thereof and it is desired, therefore, that only such limitations shall be placed thereon as are imposed by the prior art and which are set forth in the appended claims. 
     LIST OF COMPONENTS 
     (For Convenience Of The Examiner) 
       10 . Light-source enhancing lens assembly 
       20 . Carrier 
       30 . Light source 
       40 . First lens 
       42 . Cylindrical body of first lens 
       44 . First end of first lens 
       46 . Second end of first lens 
       48 . First bore 
       50 . First bore wall 
       52 . First bore end 
       54 . First hemispheric concave surface 
       56 . First bore inner surface 
       58 . Apex 
       60 . First outer surface of first lens 
       62 . First lens inner surface 
       70 . Second lens 
       72 . Convex-shaped cylindrical body of second lens 
       74 . First end of second lens 
       76 . Second end of second lens 
       78 . Second outer surface 
       80 . Second bore 
       82 . Concentric lens sections 
       84 . Top of concentric lens sections 
       86 . Second bore wall 
       88 . Second bore end 
       90 . Second concave surface 
       92 . Second inner surface 
       94 . Mounting rim