Abstract:
An illuminating device for uniformly distributing light over a rectangular portion of a plane is disclosed including a base member, an arm member connected to the base member, and a housing having a trapezoidal aperture, wherein the trapezoidal aperture is fixed in a single unit in operative engagement with the housing and wherein the housing is pivotably attached to the arm member.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS  
       [0001]    This application claims the benefit of U.S. Provisional Application Serial No. 60/340,655, filed on Dec. 14, 2001, entitled SURFACE UNIFORM ILLUMINATING DEVICE. 
     
    
     
       TECHNICAL FIELD  
         [0002]    This invention relates to a device for and method of evenly distributing light over a surface. In particular, the device and method relates to a lamp having a trapezoidal or other shaped aperture and a smooth curved internal reflector, specifically for illuminating a rectangular plane or other surface having a predetermined area.  
         BACKGROUND OF THE INVENTION  
         [0003]    This invention relates to a novel illumination source accessory to insure a uniform illumination a surface, thereby insuring that the viewer will receive the full expression that intended to be displayed by the creator.  
           [0004]    Illuminating objects, such as hanging works of art, advertisements, displays, and even walls of structures and screens with a lighting fixture of particular design is well known. These known lighting fixtures often comprise a substantially semi-cylindrical shade within which one or more tubular bulbs reside. Typically, the fixture has an extending arm incorporating the wiring, and a perpendicular portion of the extending arm reaches downward and is fixed in position by screws or the like to the back of the frame of the object to be illuminated or other substrate. In this manner, the fixture generally continues above and a particular distance out from the plane to be illuminated.  
           [0005]    An array of lamps and lighting devices are known in the lighting art, including lighting devices specifically designed for casting light on pictures or displays. Lamps for pictures typically incorporate an electric light receptacle mounted on a flexible or movable support arm, itself mounted on a connecting structure, either one designed for mounting on a wall or an adjacent support structure or one for mounting on the picture frame or display. The light receptacle often includes a housing, generally with an open bottom functioning as an aperture, and frequently with a reflector to direct the light in the direction of the picture. The support arm may be constructed as a flexible support tube or as the form of one or more rigid arm portions, the position of which can generally be adjusted.  
           [0006]    Additionally, numerous picture lamps have been proposed, including ones that use fluorescent light tubes to attain a more uniform lighting of the picture and to cast a light with color attributes that are more akin to the color attributes of sunlight. The more uniform lighting achieved by the use of a fluorescent light tube is due to the light being emitted from numerous points across the length of the light tube instead of from a single point source as is the case in an incandescent light. This, however, results in a penumbra of light that exceeds the boundaries to the rectangular plane sought to be illuminated. This penumbra distributes light over undesirable areas, such as the picture frame of a picture.  
           [0007]    Picture frames designed for display frames have been used that are frequently detachably mounted on top of a picture frame using a bracket base. The base is often connected to the frame by means of a clamping mechanism. The devices typically include a lamp receptacle that acts as a reflector and a positionable neck that is connected at a rear end to the bracket and at a front end to the light receptacle. Such lamps do not evenly distribute light over the plane sought to be illuminated and are thus unsuitable.  
           [0008]    The picture lighting fixtures of the prior art have been in existence in their current state for over fifty years and are not optimally suited for several reasons: their reflectors are not carefully designed to better reflect light; their apertures that permit the passage of light do not allow for evenly distributing light over a rectangular plane; and their apertures often are constructed in a fashion that enables light to “leak” out, thereby causing light to be unevenly distributed over the potion of the plane sought to be illuminated. More particularly, in the typical known fixture, the reflector is not designed so much to better reflect light out of a shaped aperture as it is designed to shade the light from illuminating anything but the object. As a result, the bulbs used in the known fixtures emit a relatively dim light and are often insufficient to properly light a large piece of artwork. If higher wattage bulbs are used, the light generated will continue to be unevenly distributed, and the heat generated may damage the object or objects sought to be illuminated.  
           [0009]    The illumination of works of art, advertisements, displays, and even walls of structures and screens considerably influences human perception of the work, particularly with regard to color. Most works of art, advertisements, displays, and even walls of structures and screens, and the like are frequently created while working in highly illuminated surroundings. However, the resulting works, as a practical matter, are subsequently illuminated with a small light that is positioned above and distanced somewhat away from the plane to be illuminated. Thus the viewer, most often positioned directly in front of the illuminated plane, observes the work in a light different than that in which the work was created. This is a result of the illumination intensity provided by the light source above the plane not being uniform over the surface of the plane. Therefore, the viewer does not realize the true expression of the work because the illumination intensity is distorted. Yet, to date, the lighting fixtures used to illuminate hanging works of art do not seriously address the above-described issues of light diffusion.  
           [0010]    It is an object of the present invention to provide an illuminating device that uniformly distributes light over a rectangular portion of a plane.  
           [0011]    It is a further object of the present invention to provide an illuminating device with a trapezoidal aperture so as to reduce or eliminate the penumbra caused by light leakage.  
           [0012]    It is another object of the present invention to provide an illuminating device that uniformly distributes light over a shaped area of a shaped surface.  
           [0013]    It is still another object of the present invention to provide an illuminating device with a shaped aperture so as to reduce or eliminate, the penumbra caused by light leakage.  
           [0014]    It is yet another object of the present invention to provide a relatively inexpensive illuminating device for mounting on a substrate, which device will not result in damage to the substrate mounted upon.  
           [0015]    Prior to the present invention, an illuminating device and method of uniformly distributing light, that satisfactorily solves the weaknesses associated with the more conventional methods, such as penumbras of light and lack of uniformity of light over the surface, in an efficient, practical and economically affordable manner has not been proposed or suggested by those skilled in the art.  
           [0016]    Thus, there is a need for an illuminating device and method of uniformly distributing light that overcomes the aforementioned shortcomings of the prior art.  
         SUMMARY OF THE INVENTION  
         [0017]    The present invention eliminates the above-mentioned needs for an illuminating device by providing an illuminating device and method of uniformly distributing light.  
           [0018]    In accordance with the present invention, there is provided an illuminating device for uniformly distributing light over a rectangular portion of a plane comprising a base member, an arm member moveably connected to the base member, and a housing having a trapezoidal aperture, and also pivotably attached to the arm member.  
           [0019]    The present invention is additionally directed to an illuminating device for uniformly distributing light over a shaped surface comprising, a base member, an arm member moveably connected to the base member, and a housing having a shaped aperture, and also pivotably attached to the arm member.  
           [0020]    The present invention is further directed to a method for uniformly distributing light over a rectangular area of a plane, the method comprising the steps of angling a trapezoidal aperture of a light source to a first position relative to the plane in a second position, passing light through the trapezoidal aperture from the first position to the second position, and casting a rectangular light pattern substantially equal in area to the rectangular area of the plane.  
           [0021]    The present invention is yet further directed to a method for uniformly distributing light over a shaped area of a shaped surface, the method comprising the steps of, angling a shaped aperture of a light source to a first position relative to the shaped surface in a second position, passing light through the shaped aperture from the first position to the second position, and casting a shaped light pattern substantially equal in area to the shaped area of the shaped surface. 
       
    
    
     BRIEF DESCRIPTION OF THE FIGURES  
       [0022]    [0022]FIG. 1 is a cut-away view illustration of the preferred embodiment of the present invention.  
         [0023]    [0023]FIG. 2 is a side view illustration of the present invention of FIG. 1.  
         [0024]    [0024]FIG. 3 is an isometric view illustration of an alternative embodiment of the present invention of FIG. 1.  
         [0025]    [0025]FIG. 4 is a cut-away view illustration of the alternative embodiment of the present invention of FIG. 3.  
         [0026]    [0026]FIG. 5 is front view illustration of the lighting element of the present invention of FIG. 1.  
         [0027]    [0027]FIG. 6 is side view illustration of the lighting element of the present invention of FIG. 1.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0028]    Referring now to FIG. 1, a preferred embodiment of the present invention is illustrated as illuminating device  10 . Illuminating device  10  generally comprises a base member  11 , an arm member  20  moveably connected to base member  11 , a housing  50  having a trapezoidal aperture  70 , and also pivotably attached to arm member  20 , and a curved reflector  31  internally positioned in housing  50 .  
         [0029]    As illustrated in FIG. 2, base member  11  attaches to a substrate, such as a wall, ceiling, floor, or display frame. The attachment to the substrate may be releasable or fixed, depending upon the nature of the work to be illuminated. More permanently placed works may necessitate a fixed attachment on the substrate, while more temporary works may demonstrate a need for a releasable attachment.  
         [0030]    Base member  11  includes attachment point  12  to accommodate arm member  20 . Arm member  20  includes attachment slot  21  for securing arm post  22  to base member  11 . This attachment is sufficient to support the weight of the other components of the illuminating device  10 .  
         [0031]    Referring again to FIG. 1, arm member  20  also includes arm connector  26 , which joins arm post  22  to the attachment points  23  and  25 . Attachment points  23  and  25  serve to fasten housing  50  to arm member  20 . In the preferred embodiment of the present invention, attachment points  23  and  25  serve as the pivot points for housing  50 . The housing  50  includes pivot members  51  that include slide grooves  52 . Pivot members  51  are positioned adjacent to attachment points  23  and  25 , so that a portion of slide grooves  52  pass over threaded holes  24  and  27 . Screw member  28  is used to secure slide grooves  52  in a position over threaded holes  24  and  27  with respect to the arm member  20 . Thus, the housing  50  is positionable with respect to the arm member  20  and the base member  11 .  
         [0032]    One benefit of the positionable nature of housing  50  of the preferred embodiment is that it permits the user to perform fine adjustments to the position of housing  50 .  
         [0033]    Housing  50  is itself covered by a housing sheath  40 . Housing sheath  40  is secured to housing  50  by screws or other like securing means at securing points  41 . Housing sheath  40  reduces the light leakage that may occur from housing  50 . Housing sheath  40  frictionally engages housing  50  at housing sides  53  and housing sheath slot  42  fits around pivot members  51 .  
         [0034]    As is also shown in FIG. 1, the preferred embodiment of the present invention has housing  50  that includes cooling slots  54 . The principal benefit of cooling slots  54  is that they allow for heat produced by lighting element  30  to dissipate out of housing  50 , thereby reducing the likelihood of heat damage to the illuminating device  10 . The housing sheath  40  and housing  50  combination results in an illumination device that greatly reduces the amount of light leakage.  
         [0035]    Housing  50  also includes opening  57  for incorporation of lighting element  30 . In the preferred embodiment, lighting element  30  is further secured by lighting element bracket  29 , which is itself fastened by a screw or similar fastening means to housing  50 . Additionally, as illustrated in FIGS. 3 and 4, an alternative embodiment of the illuminating device is shown as illuminating device  100 . Illuminating device  100  includes lighting element securement  29   a  to secure lighting element  30 , which passes through opening  42   a , and arm member  22   a  to housing sheath  40  and housing  50 . Lighting element securement  29   a  may be secured to housing sheath  40  and housing  50  by means of a fastener  32 . Fastener  33  may any number of fastening means, such as set screws, bolts, screws, and the like.  
         [0036]    As illustrated in FIGS. 5 and 6, the lighting element of the preferred embodiment can include a housing  35 , a filament  33 , and an internal reflector  31 . Housing  35  permits light to pass therethrough, and may be constructed of numerous materials known in the art that permit the passage of light, such as glass. Referring again to FIGS.  1 - 6 , reflector  31  is suitably shaped to reflect light produced from the rear half of lighting element  30  away from the rear of housing  50  and towards the front of housing  50 .  
         [0037]    The geometry of internal reflector  31  and its position relative to filament  33  provide a point source of light that produces a light image with a reduced penumbra effect on an illuminated surface. Generally, the greater the distance from the point source of light to the illuminated surface, the more pronounced the penumbra. Positioning internal reflector  31  inside housing  35  and behind filament  33  reduces the penumbra effect. The positioning of internal reflector  31  can reduce the penumbra effect by focusing the point source of light on the less illuminated portion of the illuminated surface. Furthermore, as shown in FIG. 6, it is preferred that internal reflector  31  be angled with respect to longitudinal axis  34  to direct more light towards the lower portion of the surface to be illuminated. Internal reflector  31  may be curved or otherwise suitably shaped to better reflect light from filament  33 . Moreover, to reduce light leakage, internal surfaces  59   a  may be coated in a light absorbing material, such as black paint. Additionally, reflector  31  may also be positioned externally (not shown) of lighting element  30  to produce a similar reflective effect. The benefit of either reflector arrangement is in facilitating a higher output of light directed at the work to be illuminated.  
         [0038]    Housing  50  also includes inset groove  55 . In the preferred embodiment, inset groove  55  accommodates light filter  60 , which can be colorless, colored, transparent, opaque, translucent, shaped or incorporating a picture. In addition, light filter  60  may also be an ultraviolet or infrared light filter. Filter  60  may also be a lens. Such a lens may include fresnel sections to assist in directing light towards the evenly at the lower portion of the surface to be illuminated. Outer edge  58  accommodates shaped aperture  70 , which is positioned over light filter  60 . Shaped aperture  70  is placed on outer edge  58  and fastened to housing  50  at aperture attachment points  56 . Shaped aperture  70  is affixed to housing  50  at aperture attachment points  56  by fastening means such as set screw, bolts, screws or the like.  
         [0039]    Shaped aperture  70  includes aperture  71  and housing attachment points  72 . Housing attachment points  72  are aligned with aperture attachment points  56  and subsequently fastened by fastening means such as screws or the like. Furthermore, shaped aperture  70  is formed of a single, unitary piece. This construction significantly reduces the amount of light leakage out of housing  50 , which, in conjunction with internal reflector  31  and its position relative to filament  33 , results in a significant reduction of the penumbra of light typically associated with more traditional illuminating devices.  
         [0040]    Moreover, aperture  71  can include a variety of shapes. In one embodiment of the present invention, aperture  71  is trapezoidal in shape. The benefit to using shaped aperture  71  is that it casts a light pattern that, when angled with respect to the corresponding surface to be illuminated, conforms to the exact dimensions of the surface to be illuminated. Thus, with respect to aperture  71  shown in FIG. 1, the trapezoidal shape of the aperture casts a light pattern that appears as a rectangle of on the surface to be illuminated having dimensions exactly conforming to those of the surface to be illuminated, such as a picture. Similarly, in another embodiment, aperture  71  can be formed in a manner that permits a light pattern to be cast that conforms to the surface of any shaped surface to be illuminated.  
         [0041]    For example, an unclothed mannequin may be illuminated by the present invention using an aperture shaped in a manner consistent with illuminating the mannequin at a particular angle. At such an angle, the light pattern cast by the illuminating device would cover the mannequin in a clean and clearly defined manner, creating the appearance that the mannequin itself is colored. Moreover, if the filter used incorporated a picture of, for example, clothing, the mannequin would appear to be wearing the clothing projected upon the mannequin. Such a projection, due to the angle of the housing and the shape of the aperture, would appear proportional on the mannequin. A user could easily remove a filter and replace it with another much more quickly than changing a display.  
         [0042]    In practicing the method of the preferred embodiment, a front portion of housing  50  is angled with respect to the object to be illuminated so that the aperture  71  is placed in a first position relative to a plane in a second position. The plane in the second position includes the surface to be illuminated, such as a picture, mannequin, or other display piece. Lighting element  30  generates light that passes through the shaped aperture from the first position to the second position, thus lighting the surface. The light is thus cast in a shaped light pattern substantially equal in area to the shaped area of the shaped surface. The cast light pattern, in combination with the reflector internally positioned in the housing, produces a uniform distribution of light over the shaped surface.  
         [0043]    Although only a few exemplary embodiments of the present invention have been described in detail above, those skilled in the art will readily appreciate that numerous modifications are to the exemplary embodiments are possible without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the following claims.